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The demand for more ecological, highly engineered hydrogel beads is driven by a multitude of applications such as enzyme immobilization, tissue engineering and superabsorbent materials. Despite great interest in hydrogel fabrication and utilization, the interaction of hydrogels with water is not fully understood. In this work, NMR relaxometry experiments were performed to study bead-water interactions, by probing the changes in bead morphology and surface energy resulting from the incorporation of carboxymethyl cellulose (CMC) into a cellulose matrix. The results show that CMC improves the swelling capacity of the beads, from 1.99 to 17.49, for pure cellulose beads and beads prepared with 30% CMC, respectively. Changes in water mobility and interaction energy were evaluated by NMR relaxometry. Our findings indicate a 2-fold effect arising from the CMC incorporation: bead/water interactions were enhanced by the addition of CMC, with minor additions having a greater effect on the surface energy parameter. At the same time, bead swelling was recorded, leading to a reduction in surface-bound water, enhancing water mobility inside the hydrogels. These findings suggest that topochemical engineering by adjusting the carboxymethyl cellulose content allows the tuning of water mobility and porosity in hybrid beads and potentially opens up new areas of application for this biomaterial.

1. The covalent attachment of pyruvate kinase to filter-paper disks and some kinetic properties of the resultant enzymically active porous sheets are described. 2. A two-enzyme reactor was constructed by using water-insoluble sheets of lactate dehydrogenease in conjunction with the above-mentioned sheets possessing pyruvate kinase activity.

Coconut husk, an agricultural waste, is abundant in Thailand due to the extensive presence of coconut farms. This current research aimed to determine how to add the value to the coconut husk and examine its ability to absorb dyes used for aquaculture. The research consisted of cellulose production, determination of cellulose qualifications, and assessment of the efficiency of coconut husk and its cellulose to absorb KMnO4. The efficiency of absorption was based on absorption time, the amount of absorbent, and effect of salinity and temperature. Results showed that cellulose derived from coconut husks exhibited greater viscosity, strength, and tensile resistance compared to coconut husk fibers with 48.10 % yield of the extraction. SEM analysis revealed that the outer surface of cellulose is microporous. FTIR analysis revealed that the composition of produced cellulose was similar to the commercially produced one. The structure of cellulose showed 2Ɵ peaks at positions of 16° and 23° with thermal degradation ranging from 75 to 130 °C (residue 90.76 %) and 290–385 °C (residue 27.69 %). The maximum duration for absorption was 4 hours for both cellulose (88.40 ± 4.20 %) and coconut husks (83.20 ± 5.40 %). The absorption efficiency of cellulose increased when the content increased and it showed a significantly (p

Recent advances in the production and use of cellulose nanoparticles are detailed in this review. Global demand for sustainability is on the rise, and fossil fuel use is also on the rise. Consequently, the oil and gas industry must maintain its focus on R&D of new, environmentally friendly technologies and materials. Oil and gas companies are interested in cellulose nanoparticles (CNMs) for several reasons, including their renewable potential, high specific surface area, adjustable surface chemistry, and good mechanical, barrier, thermal, and rheological characteristics. Oil and gas production will become more sustainable and environmentally friendly as a result of all this. There are many manufacturing procedures that may be used to manufacture materials with different structures and physicochemical qualities. Biomedicine, sensing, wastewater treatment, paper and cardboard manufacture, and the packaging sector are just a few of the many fields that benefit from cellulose nanomaterials (CNMs), especially cellulose nanofibers and cellulose nanocrystals. These materials have several desirable characteristics, such as being renewable, having a large surface area, being very stiff and strong under tension, and being very flexible on the surface because of hydroxyl groups. This has led to the scale production of these materials; for example, several companies currently make cellulose nanoparticles in quantities of several tons per day. The remarkable properties of nano-cellulose biopolymers, which may be produced by a wide range of microbes and plant materials, including rice husks, tea leaves, and other agricultural byproducts, have recently attracted more attention due to the development of nanotechnology. Scientists use a range of methods, including chemical, mechanical, and enzymatic processes, to synthesize cellulose nanoparticles from food scraps. Nanomaterials' primary characteristics are defined by their surface functionalization, extraction source, and extraction processes. In this article, we will examine their present production rates and their applications in several areas, including as healthcare, sustainable construction materials, and energy storage and generation. Our focus will be on recent developments and upcoming trends in the production and use of cellulose nanoparticles. The purpose of this article is to provide a synopsis of what is known about cellulose and its technical biological uses, including its ability to heal wounds, transport drugs, construct tissues, and regenerate bones. The most recent findings from both basic and applied research are contained in a comprehensive bibliography. Materials derived from cellulose may be modified to possess the specific physical, mechanical, and chemical characteristics needed for use in the biomedical field. It doesn't take much work to alter cellulose's chemical structure and conjugate it with other materials, including nanoparticles. Because of this, the applications are straightforward to form and process, inexpensive, biodegradable, and biocompatible.

Natural deep eutectic solvent (NADES) composed of choline chloride and formic acid was used to fractionate date waste into lignin and cellulose streams. NADES treatment increased the cellulose content from 44 wt% in raw waste (RW) to 72 wt% in extracted cellulose fibers (CFs). Scanning electron microscopy revealed needle-like fibers, underlining the effectiveness of NADES treatment in removing non-cellulosic components. Additionally, the CFs exhibited improved thermal stability, with an initial decomposition temperature (Tonset) of 265 °C. Kinetic analysis revealed a higher activation energy (Ea) of 100.90 kJ/mol for CFs than 63.10 kJ/mol for RW, indicating higher thermal stability due to enhanced cellulose content. Pyrolysis coupled with gas chromatography/mass spectroscopy analyses of CFs showed a lower release of nitrogen compounds and a higher content of hydrocarbons and cyclic ethers, all of which are beneficial for bio-oil production. Overall, the findings of this study will promote the use of NADES as an inexpensive, nontoxic, and recyclable solvent to advance the field of selective pyrolysis.

Cellulose nanofibrils (CNF) are promising renewable materials due to their high surface area, abundance, and ease of modification. This study explores the impact of source material on CNF properties for diverse applications like drug delivery and composites. CNF were prepared from corn cob (CC), bagasse (BG), waste wood (WW), and bacterial cellulose (BC) using TEMPO-mediated oxidation. Microcrystalline cellulose (MCC) was also oxidized (MCC-ox) for comparison. The transparency, chemical structure, crystallinity index, and surface charge of the resulting CNF were investigated. As a result, all CNF yields ranged from 25 % to 34 %. FT-IR analysis confirmed successful TEMPO oxidation by detecting carboxyl groups on all CNF surfaces. BC-derived CNF displayed the second-highest transparency after MCC. Surface charge analysis revealed the highest carboxyl content in MCC-ox (8828.39 mmol/kg), followed by CNF-BC (8438.84 mmol/kg), CNF-CC (7687.24 mmol/kg), CNF-WW (6720.43 mmol/kg), and CNF-BG (5505.61 mmol/kg). XRD analysis indicated the highest crystallinity index in MCC-ox (83.40 %) due to its high purity, followed by CNF-BC (82.52 %) likely due to its nanostructure and high purity, and CNF-CC (78.14 %) potentially due to the rigid and dense structure of corn cobs. These findings provide valuable insights into selecting CNF with the desired characteristics for various fields such as material science, nanotechnology, and biomedicine.

Interest in hemp as a viable cellulosic fibre for clothing has increased, driven partly by its economic benefits and the importance of natural renewable materials in emerging circular economies. However, the coloration and chemical finishing of lignocellulosic fibres such as hemp typically require large quantities of water and chemicals. Argon plasma pretreatment provides a way of modulating the physical properties of hemp fibres to improve the coloration process without compromising other bulk properties such as tensile strength. Such plasma treatments may contribute to alleviating the negative environmental impacts associated with liquid pretreatments, heating, or the use of auxiliary chemicals. Dyeing of hemp fibres is particularly challenging due to its crystalline chemical structure. In this study, low-pressure argon plasma-assisted surface modification of woven hemp fabrics up to 600 s at 40 and 80 Hz was explored for enhanced dyeability, resulting in enhanced dye-fibre bonding. Fourier-transform infrared spectroscopy and Raman spectroscopy of argon plasma pretreated hemp fabrics produced no noticeable changes in the functional groups of the fibres, but a physiochemical modification was observed in terms of the density of polar groups. Scanning electron microscopy (SEM) images revealed marked morphological changes including nano-etching of the fibre surface at certain argon plasma process conditions. The pretreatment process increased fibre hydrophilicity, and enhanced reactivity of the surficial –OH groups towards fibre-reactive and vat dyes, resulting in higher colour strength in dyed woven hemp fabrics. Overall, we envisage such plasma pretreatments may impact positively on the material and energy efficiency of the hemp fabric dyeing process.

This research explores the extraction and application of cellulose fibers from various parts of plants, specifically young and old stems, as well as seed/fruit skins. The primary focus was on the effective removal of lignin and other extraneous compounds to enhance the properties of cellulose fibers for their subsequent use as fillers in the production of porous composites. These composites were evaluated for their responsiveness to ammonia vapor through a color change test, indicating their potential as intelligent, environmentally friendly packaging materials. The cellulose fibers were isolated through a two-stage process involving delignification using 20 % sodium hydroxide (NaOH) and bleaching with a 5 % hydrogen peroxide (H2O2) and 3.8 % NaOH mixture. These fibers were then characterized using Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffractometry (XRD), and Scanning Electron Microscopy (SEM). The analysis revealed that fibers extracted from the younger stem bark exhibited superior characteristics, notably in their crystallinity index (CI), which was 5.16 % higher than that of fibers from other plant parts. Surface morphological studies indicated that the cellulose fibers derived from CG plants possess a hollow shape. When used as fillers, these fibers contributed to the enhanced porosity of polyvinyl alcohol/polyvinylpyrrolidone (PVA/PVP) composites. SEM analysis further demonstrated that the inclusion of fibers with higher degrees of crystallinity significantly increased the composites' porosity. Additionally, composites immobilized with anthocyanins from the Butterfly Pea Flower (BPF) exhibited a notable colorimetric response to environmental pH changes. Thermogravimetric analysis suggested that incorporating these fibers into the composite matrix improves thermal stability. The study's findings underscore the potential of these porous composites as colorimetric indicators, paving the way for their application in smart, eco-friendly packaging solutions.

Interactions of cellulose- and lignin-derived intermediates have been well documented during pyrolysis of lignocellulosic biomass. The reaction network for the interactions is rather complex, as cellulose-derived volatiles could interact/react with not only lignin-derived volatiles but also lignin-derived char and vice versa. To probe specifically the impacts of cellulose-derived volatiles on the lignin-derived char or the opposite, herein the sequential pyrolysis was performed by arranging cellulose in the upper bed with lignin in the lower bed or lignin above with cellulose below at 350 and 650 °C, respectively. The results indicated that the sequential pyrolysis of cellulose→lignin or lignin→cellulose at 350 °C induced increased char yield from formation of carbonaceous deposits via volatiles-char interactions. Compared with the lignin-derived volatiles, the cellulose-derived volatiles, especially aldehyde fractions, were more reactive towards the lignin-derived char at 350 °C, forming oxygen-rich lignin-derived char with a higher yield, an abundance of aliphatic structures and consequently lower thermal stability. In sequential pyrolysis of lignin→cellulose, more aromatics-rich species were deposited on cellulose-derived char, but the lignin-derived volatiles were less reactive for enhancing the char yield. At 650 °C, instead of polymerisation of the volatiles on the char, either the cellulose- or lignin-derived char catalyzed the cracking of the counterpart volatiles to remove the aliphatic functionalities, which made the char more aromatic and thermally more stable.

Sulfonated polysulfone (SPS) composite membranes consisting of cellulose-based carbon nanodots (CNDs) were successfully prepared as a proton exchange membrane (PEM) for direct methanol fuel cell (DMFC) applications. The CNDs were prepared using the top-down hydrothermal method. The structure transformation from cellulose to CNDs was confirmed by the FTIR and XRD analysis. The particle size of CNDs was between 1 and 3 nm. The particles exhibited good optical properties. The incorporation of CND into matrix polymer increased the thermal stability of the membranes. Morphology analysis of the SPS/CND composite membranes revealed that CNDs had been successfully dispersed within the SPS polymer matrix. The cross-linking between SPS and CNDs enhanced the proton conductivity of the composite membranes compared to the pristine SPS membrane. The SPS/CND-1 (1 wt%) exhibited the highest selectivity with a proton conductivity of 35.5 mS.cm−1 and a methanol permeability of 3.50 × 10−6 cm2.s−1. The experimental results indicate that the incorporation of CNDs into the SPS membrane also decreased the amount of methanol that can pass through the membrane when used in DMFCs.

Cellulose-based hierarchical porous beads exhibit significant application potential in adsorption and separation systems due to their degradation and biocompatibility. However, the current fabrications of cellulose beads show poor mechanical properties and a difficult-to-regulate hierarchical porous structure, reducing their lifespan of use and limiting their application in fine separation. Here, we reported the facile creep–drop method to prepare cellulose beads that enabled systemic regulation of the macro-size, micropore structures, and mechanical properties by optimizing injection nozzle diameter, the composition of the coagulation bath, the temperature of the coagulation bath, and cellulose concentration. Notably, during the molding process, the H2SO4-Na2SO4 composite solidification bath endowed cellulose beads with a dense shell layer and a loose core layer, which achieved the integration of mechanical properties and high porosity. The cellulose beads exhibited high porosity (93.38–96.18%) and high sphericity (86.78–94.44%) by modulating the shell thickness of the cellulose beads. In particular, the cellulose beads exhibited excellent mechanical properties with a high compressive strength of 544.24 kPa at a 5% cellulose concentration. It is expected that these cellulose beads with tunable microstructures can realize their potential for applications in the fields of wastewater treatment, chemical engineering, bioengineering, medicine, and pharmaceuticals. [ABSTRACT FROM AUTHOR]

The high production of kepok banana is generating a significant amount of peel waste, contributing to environmental pollution. To address this issue, an innovative solution is the conversion of kepok banana peel into cellulose acetate as raw material for membrane production. Therefore, this research aimed to manufacture kepok banana peel cellulose acetate using varying concentrations of 1%, 1.5%, and 2% NaOH solvent, with acetylation times of 2 hours and 2.5 hours, respectively. The optimal results were achieved using 1% NaOH with kepok banana peel cellulose content of 56.07%. Furthermore, the best acetylation time occurred at a duration of 2.5 hours, producing a cellulose acetate content of 38.23% and a 2.3% degree of substitution (DS). These results suggested that the optimal combination for producing membrane from kepok banana peel is 1% concentration with an acetylation time of 2.5 hours, classifying it as cellulose diacetate.

Cellulose, a sustainable raw material, holds great promise as an ideal candidate for membrane materials. In this work, we focused on establishing a low-cost route for producing cellulose microfiltration membranes by adopting a co-solvent system comprising the ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc) and acetone. The introduction of acetone as a co-solvent into the casting solution allowed control over the viscosity, thereby significantly enhancing the morphologies and filtration performances of the resulting cellulose membranes. Indeed, applying this co-solvent allowed the water permeability to be significantly increased, while maintaining high rejections. Furthermore, the prepared cellulose membrane demonstrated excellent fouling resistance behavior and flux recovery behavior during a challenging oil-in-water emulsion filtration. These results highlight a promising approach to fabricate high-performance cellulose membranes.

This is the first proof of concept of generating hydrophobic nanocelluloses by facile one-pot solventless telomerization using butadiene sulfone (BDS) to serve the dual functions of 1,3-butadiene (BD) reagent and reaction medium. Optimal telomerization of BD at 6 equiv of 2,7-octadienyl ether (ODE) to amorphous cellulose anhydroglucose (AGU) at 110 °C, or 6ODE110, and then disintegration by shear force yielded ca. 27−41% hydrophobic DMSO, THF, and CHCl3 dispersible nanocelluloses in 3.7, 6.3, and 4.4 nm thickness, respectively. The surface ODE group was evidenced in methylene peaks at 2800−2980 cm−1 and C=C at 1640−1704 cm−1 by FTIR and in both cis and trans C2−C3 double-bond conformations at 700 and 956 cm−1, respectively, by FTIR-ATR. Solution-state 1H NMR elucidated the ODE structure (d6-DMSO; δ 1.47, 1.95, and 2.07 ppm and 4.86, 5.29, 5.61, 5.90, and 6.07 ppm for methylene and olefinic protons, respectively) along with cellulosic protons (δ 4.12, 3.08, 3.28, 3.40, 3.53, 3.19, and 3.93 ppm for H1, 2, 3, 4, 5, 6a, and 6b, respectively), indicating a 30% conversion of surface OH to ODE. ODE-CNFs exhibited far superior thermal stability with a Tmax of 332 °C, 67 °C higher than that of TEMPO-CNFs. Most impressively, 1% ODE-NCs effectively converted hydrophilic solid mica and porous cellulose paper to hydrophobic surfaces with outstanding 102 ± 1 and 94 ± 2° water contact angles, respectively.

Membranes are a selective barrier that allows certain species (molecules and ions) to pass through while blocking others. Some rely on size exclusion, where larger molecules get stuck while smaller ones permeate through. Others use differences in charge or polarity to attract and repel specific species. Membranes can purify air and water by allowing only air and water molecules to pass through, while preventing contaminants such as microorganisms and particles, or to separate a target gas or vapor, such as H2 and CO2, from other gases. The higher the flux and selectivity, the better a material is for membranes. The desirable performance can be tuned through material type (polymers, ceramics, and biobased materials), microstructure (porosity and tortuosity), and surface chemistry. Most membranes are made from plastic from petroleum-based resources, contributing to global climate change and plastic pollution. Cellulose can be an alternative sustainable resource for making renewable membranes. Cellulose exists in plant cell walls as natural fibers, which can be broken down into smaller components such as cellulose fibrils, nanofibrils, nanocrystals, and cellulose macromolecules through mechanical and chemical processing. Membranes made from reassembling these particles and molecules have variable pore architecture, porosity, and separation properties and, therefore, have a wide range of applications in nano-, micro-, and ultrafiltration and forward osmosis. Despite their advantages, cellulose membranes face some challenges. Improving the selectivity of membranes for specific molecules often comes at the expense of permeability. The stability of cellulose membranes in harsh environments or under continuous operation needs further improvement. Research is ongoing to address these challenges and develop advanced cellulose membranes with enhanced performance. This article reviews the microstructures, fabrication methods, and potential applications of cellulose membranes, providing some critical insights into processing–structure–property relationships for current state-of-the-art cellulosic membranes that could be used to improve their performance.

Physical adsorption has shown to be facile and highly effective to deposit chitosan nanowhiskers (CsNWs, 60 % deacetylated, length: 247 nm, thickness: 4-12 nm, width:15 nm) on electrospun cellulose acetate nanofibers (CANFs, 560 nm) to effect complete surface charge reversal from negatively charged CANFs (-40 mV) to positively charged CsNWs-adsorbed CANFs (+8 mV). The CsNWs coverage did not alter the smooth and homogeneous morphology of fibers, as observed from SEM images. Biological assays showed the CsNWs covered nanofibers were effective against the Gram-negative bacterium E. coli, reducing 99 % of colony forming units (CFU) in 24 h and atoxic to healthy Vero cells. The use of CsNWs to modify cellulose fiber surfaces has been proved to be efficient and may be applied to a broad scope of fields, especially as biomaterials and biomedical applications.

Nature-inspired technology has been investigated widely. Anti biofouling properties of fish scale has inpired to improve membrane performance. Biofouling affects an oil-water separation membrane. The bacterial, coagulant, and hydrophobic oils attach to the membrane surface, demanding periodic cleaning. To overcome the problems, surface modification materials are introduced namely superoleophobic surface. The superoleophobic surface promises antifouling, high flux, and high separation efficiency. Superoleophobic surfaces are inspired by the scales on fish that form a hydrogel-like layer on their surface. The hydrogel repels oil and any organic materials, keeping the surface clean. The hydrogel of fish scales can be mimicked by cellulose-based materials. A dense layer of hydroxyl groups absorbs a lot of water and forms a hydrogel bond. The membrane with the cellulose hydrogel-like structure will perform a superoleophobic characteristic surface. The characteristic can be utilized as a functional membrane for oil-water separation. This article reviews the principle, mechanism, current development, and future challenges of bioinspired superoleophobic surfaces from cellulose-based materials for membrane applications.

A pretreatment process is needed in the bioconversion of oil palm empty fruit bunch (OPEFB) to remove lignin and to get crystalline cellulose for CNC production. Several pretreatment methods were studied, i.e., pretreatment with 10% NaOH, combination method of 10% NaOH and H2O2 (1.5% and 24%), as well as 10% NaOH and NaClo2 (1.4% and 12%). In the combination method, washing was applied in between processes to reach the pH of ± 6. The temperature for the pretreatment processes was 70 ◦C. The pH for pretreatment with 10% NaOH was ± 13, the pH for pretreatment with H2O2 (1.5% and 24%) was ± 8 and ± 6, and the pH for pretreatment with NaClO2 (1.4% and 12%) was adjusted to 4. The results showed that the highest lignin removal of 100% and the highest whiteness index were obtained after the combination pretreatment with 10% NaOH and 12% NaClO2. The highest cellulose yield of 65.33% was obtained after pretreatment with 10% NaOH. The combination pretreatment with 10% NaOH and 1.4% NaClO2 produced the highest crystallinity index of 69.35% from the cellulose obtained. The X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy results confirmed the presence of the cellulose obtained. Based on the value of the crystallinity index and considering the values of lignin removal, whiteness index, and cellulose yield, the combination pretreatment with 10% NaOH and 1.4% NaClO2 was selected as the suggested process.

BackgroundWe recently confirmed that the deactivation of T. reesei cellulases at the air-liquid interface reduces microcrystalline cellulose conversion at low enzyme loadings in shaken flasks. It is one of the main causes for lowering of cellulose conversions at low enzyme loadings. However, supplementing cellulases with small quantities of surface-active additives in shaken flasks can increase cellulose conversions at low enzyme loadings. It was also shown that cellulose conversions at low enzyme loadings can be increased in unshaken flasks if the reactions are carried for a longer time. This study further explores these recent findings to better understand the impact of air-liquid interfacial phenomena on enzymatic hydrolysis of cellulose contained in Avicel, Sigmacell, α-cellulose, cotton linters, and filter paper. The impacts of solids and enzyme loadings, supplementation with nonionic surfactant Tween 20 and xylanases, and application of different types of mixing and reactor designs on cellulose hydrolysis were also evaluated.ResultsAvicel cellulose conversions at high solid loading were more than doubled by minimizing loss of cellulases to the air-liquid interface. Maximum cellulose conversions were high for surface-active supplemented shaken flasks or unshaken flasks because of low cellulase deactivation at the air-liquid interface. The nonionic surfactant Tween 20 was unable to completely prevent cellulase deactivation in shaken flasks and only reduced cellulose conversions at unreasonably high concentrations.ConclusionsHigh dynamic interfacial areas created through baffles in reactor vessels, low volumes in high-capacity vessels, or high shaking speeds severely limited cellulose conversions at low enzyme loadings. Precipitation of cellulases due to aggregation at the air-liquid interface caused their continuous deactivation in shaken flasks and severely limited solubilization of cellulose.

BackgroundTrichoderma reesei is one of the major producers of enzymes for the conversion of plant biomass to sustainable fuels and chemicals. Crude plant biomass can induce the production of CAZymes in T. reesei, but there is limited understanding of how the transcriptional response to crude plant biomass is regulated. In addition, it is unknown whether induction on untreated recalcitrant crude plant biomass (with a large diversity of inducers) can be sustained for longer. We investigated the transcriptomic response of T. reesei to the two industrial feedstocks, corn stover (CS) and soybean hulls (SBH), over time (4 h, 24 h and 48 h), and its regulatory basis using transcription factor deletion mutants (Δxyr1 and Δara1). We also investigated whether deletion of a xylulokinase gene (Δxki1) from the pentose catabolic pathway that converts potential inducers could lead to increased CAZyme gene expression.ResultsBy analyzing the transcriptomic responses using clustering as well as differential and cumulative expression of plant biomass degrading CAZymes, we found that corn stover induced a broader range and higher expression of CAZymes in T. reesei, while SBH induced more pectinolytic and mannanolytic transcripts. XYR1 was the major TF regulating CS utilization, likely due to the significant amount of d-xylose in this substrate. In contrast, ARA1 had a stronger effect on SBH utilization, which correlates with a higher abundance of l-arabinose in SBH that activates ARA1. Blocking pentose catabolism by deletion of xki1 led to higher expression of CAZyme encoding genes on both substrates at later time points. Surprisingly, this was also observed for Δara1 at later time points. Many of these genes were XYR1 regulated, suggesting that inducers for this regulator accumulated over time on both substrates.ConclusionOur data demonstrates the complexity of the regulatory system related to plant biomass degradation in T. reesei and the effect the feedstock composition has on this. Furthermore, this dataset provides leads to improve the efficiency of a T. reesei enzyme cocktail, such as by the choice of substrate or by deleting xki1 to obtain higher production of plant biomass degrading CAZymes.

Microencapsulation methods in product development may result in innovative products with improved stability, functionality, and active chemical release (s). Microcapsules may be made out of biopolymers instead of synthetic polymers because of their biodegradability, lower production costs, and greater accessibility. The potential of biopolymers-based microencapsulation technology in sustainable textiles is substantial despite this field only getting started. This short review explores the role of biopolymers such as chitosan, gelatin, alginate, and cellulose in microencapsulation-mediated sustainable textile technology. The long-term effects of using microencapsulation made from biopolymers are also discussed, with an eye toward sustainability.

Photocatalysis has been widely known as a simple green technology to be applied in the synthesis and degradation process of organic molecules. An application of photocatalysis in a biomass pretreatment for a 5-hydroxymethylfurfural (5-HMF) production was investigated in this study. The results have revealed that photocatalysis, applied during pretreatment, facilitates the breakdown of cellulose. The presence of oxidizing agent (H2O2) in the ratios to cellulose of 11:1, 18:1, and 37:1 mol.mol-1 has been investigated for its effect on the production of 5-HMF. The optimum conditions obtained for the pretreatment process was the presence of H2O2 at 37:1 mol.mol-1, which was followed by the process of evaporation of the remaining H2O2 after pretreatment. The 5-HMF yield from the hydrolysis process involving pretreatment was 13.07%, while the yield from the process without pretreatment was 9.79%. The application of the pretreatment has succeeded in increasing the 5-HMF yield by 25.09%. The progress in the pretreatment was also marked by the presence of the carboxyl groups in the pretreated samples which were observed by the Fourier Transforms Infrared spectroscopy (FTIR). Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

One of the most important biofuels is cellulose ethanol which is a popular material for bioethanol production. The present cellulosic ethanol production is through the cellulolytic process and this involves the splitting of complex cellulose into simple sugars through the hydrolysis process of the lignocellulose pretreated with acids and enzymes after which the product is fermented and distilled. There are, however, some challenges due to the enzymatic and acid processes based on the fact that acid hydrolysis has the ability to corrode equipment and cause unwanted waste while the enzymatic hydrolysis process requires a longer time because enzymes are costly and limited. This means there is a need for innovations to minimize the problems associated with these two processes and this led to the application of solid catalysts as the green and effective catalyst to convert cellulose to ethanol. Solid catalysts are resistant to acid and base conditions, have a high surface area, and do not cause corrosion during the conversion of the cellulose due to their neutral pH. This review, therefore, includes the determination of the cellulose potential as feedstock to be used in ethanol production as well as the preparation and application of solid catalyst as the mechanism to convert cellulose into fuel and chemicals. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

In the shadow of a burgeoning biomass-to-fuels industry, biological conversion of lignocellulose to fermentable sugars in a cost-effective manner is key to the success of second-generation and advanced biofuel production. For the effective comparison of one cellulase preparation to another, cellulase assays are typically carried out with one or more engineered cellulase formulations or natural exoproteomes of known performance serving as positive controls. When these formulations have unknown composition, as is the case with several widely used commercial products, it becomes impossible to compare or reproduce work done today to work done in the future, where, for example, such preparations may not be available. Therefore, being a critical tenet of science publishing, experimental reproducibility is endangered by the continued use of these undisclosed products. We propose the introduction of standard procedures and materials to produce specific and reproducible cellulase formulations. These formulations are to serve as yardsticks to measure improvements and performance of new cellulase formulations.

Developing a hybrid composite polymer membrane with desired functional and intrinsic properties has gained significant consideration in the fabrication of proton exchange membranes for microbial fuel cell applications. Among the different polymers, a naturally derived cellulose biopolymer has excellent benefits over synthetic polymers derived from petrochemical byproducts. However, the inferior physicochemical, thermal, and mechanical properties of biopolymers limit their benefits. In this study, we developed a new hybrid polymer composite of a semi-synthetic cellulose acetate (CA) polymer derivate incorporated with inorganic silica (SiO2) nanoparticles, with or without a sulfonation (–SO3H) functional group (sSiO2). The excellent composite membrane formation was further improved by adding a plasticizer (glycerol (G)) and optimized by varying the SiO2 concentration in the polymer membrane matrix. The composite membrane’s effectively improved physicochemical properties (water uptake, swelling ratio, proton conductivity, and ion exchange capacity) were identified because of the intramolecular bonding between the cellulose acetate, SiO2, and plasticizer. The proton (H+) transfer properties were exhibited in the composite membrane by incorporating sSiO2. The composite CAG–2% sSiO2 membrane exhibited a higher proton conductivity (6.4 mS/cm) than the pristine CA membrane. The homogeneous incorporation of SiO2 inorganic additives in the polymer matrix provided excellent mechanical properties. Due to the enhancement of the physicochemical, thermal, and mechanical properties, CAG–sSiO2 can effectively be considered an eco-friendly, low-cost, and efficient proton exchange membrane for enhancing MFC performance.

In this work, the Cellulose MicroFibers (CMF) were produced by using Recycled Newspaper Paper (RNP). The two adsorbents (CMF) and (RNP) were used in the adsorption of the basic textile dye BY28. RNP was characterized by X-ray diffraction and FT-IR spectroscopy while the morphology was visualized by SEM analysis. The chemical composition was determined by EnergyDispersive Spectroscopy (EDS); the characteristics showed a good extraction of cellulose from a newspaper pulp compared to cellulose alone. The release of RNP was followed by measuring both the absorbance and Chemical Oxygen Demand (COD) in water after washing and deinking. Alkaline pH medium has a positive effect on the release of various compounds of the pulp. The adsorption of BY28 on RNP and CMF according to various parameters such as biosorbent dose (1 - 8 g) and initial BY28 concentration (25 - 200 mg/L) was investigated. The adsorption isotherms were studied by using the Langmuir and Freundlich. Maximal RNP and CMF adsorption capacities of 91.21 and 52.67 mg/g respectively were obtained at 20 °C.

Polyethylene-cellulose biocomposites were synthesized here via the ethylene polymerization with metallocene as a catalyst along with methylaluminoxane (MAO) as a cocatalyst. The immobilization method in which the catalyst or cocatalyst is fixed onto the catalytic filler (cellulose) can be classified into 3 methods according to the active components fixed onto the filler surface: 1) only metallocene catalyst (Cellulose/Zr), 2) only MAO cocatalyst (Cellulose/MAO) and 3) mixture of metallocene and MAO (Cellulose/(Zr+MAO)). It was found that the different immobilization methods or different fillers altered the properties of the obtained composites and also the catalytic activity of the polymerization systems. It was found that Cellulose/MAO provided the highest catalytic activity among all fillers due to a crown-alumoxane complex, which caused the heterogeneous system with this filler behaved similarly to the homogeneous system. The different fillers also produced the biocomposites with some different properties such as crystallinity which Cellulose/Zr provided the highest crystallinity compared with other fillers as observed by a thermal gravimetric analysis-differential scanning calorimetry (TGA-DSC). Nevertheless, the main crystal structure indicated to the typical polyethylene was still observed for all obtained biocomposites with different fillers as observed by an X-ray diffractometer (XRD). Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Recycling plant-based materials for various applications not only reduces the harm to the environment but also presents an excellent green source for nanomaterial synthesis. Being chiral and biodegradable makes cellulose, which is an organic polymer, an economic and easy-to-access plant-derived green material. Cellulose can be synthesized into nanostructures for a vast array of high-demand applications, such as drug delivery; biomedicines, which includes “biosensors and diagnostics”; medical implants; skin tissue healing; wastewater treatment; touch screen technology; electronic skin; human–machine interfaces; flexible devices; energy storage devices; clothes; packaging; and cosmetics. The daily newspapers that are delivered to our homes can be one of the best sources of cellulose for us. Our work in this study concentrated on removing nanocrystalline cellulose from newspapers. To begin, we deinked the newspapers and then the deinked pulp was transformed into its nanostructures, or nanocrystalline cellulose, to achieve a high aspect ratio, on the one hand, using chemicals like NaOH, thiourea, etc., and on the other side, via a mechanical process. We used a variety of characterization techniques, including scanning electron microscopy to study morphological properties, X-ray diffraction, and dynamic light scattering for dimensional analysis, Fourier transforms infrared spectroscopy for thermogravimetric analysis, and others, to confirm that the synthesized materials had achieved the intended outcomes. A high aspect ratio enables us to create surfaces with a huge surface area with very little synthetic material. The final product, which was created by synthesis, has been discovered to have features that are identical to those of nanocrystalline cellulose, which is available for purchase in the market for use in laboratory purposes. To make nanocomposites, this nanocrystalline cellulose can be combined with various organic and inorganic polymers, which can be further used as a base material for energy storage devices. In this paper, we compared our materials at different time durations used in synthesis.

Pure cellulose has been successfully isolated from tomato peels by either acidified sodium chlorite or chlorine-free alkaline peroxide routes, at 10.2-13.1% yields. Negatively charged (ζ = -52.4 mV, 0.48 at% S content) and flat spindle shaped (41:2:1 length:width:thickness) cellulose nanocrystals (CNCs) were isolated at a 15.7% yield via sulfuric acid hydrolysis (64% H2SO4, 8.75 mL/g, 45 °C, 30 min). CNCs could be facilely assembled from dilute aqueous suspensions into highly crystalline (80.8%) cellulose Iβ fibrous mass containing mostly sub-micron fibers (ϕ = 260 nm) and few interconnected nanofibers (ϕ = 38 nm), with 21.7 m(2)/g specific surface and 0.049 m(3)/g pore volume. More uniformly nanofibers with average 42 nm width and significantly improved specific surface area (101.8m(2)/g), mesoporosity and pore volume (0.4m(3)/g) could be assembled from CNCs in 1:1 v/v tert-butanol/water mixture.

Non-steroidal anti-inflammatory drugs are well-known medications for reducing pain and a group of drugs that can cause mucosal damage of the stomach. The negative effects on the digestive system can be reduced by immobilization of drugs on various carriers, for instance, on the components of plant biomass, for the creation of drug delivery system. Plant biomass is a lignocellulosic complex consisting of lignin, cellulose and hemicellulose that can potentially be regarded as a carrier of pharmaceuticals. Sugarcane residues such as bagasse and straw are biomass by-products of the sugarcane industry. One of the prospective ways for their efficient utilization can include chemical processing with the aim of obtaining effective biosorbents or so-called carriers of different composition and structure. The aim of the work was to study the structural, morphological, and sorption properties of cellulose, lignin, and lignocellulose, derived from sugarcane biomass (bagasse and straw) by means of delignification and hydrolysis, as potential components for drug delivery system. Sugarcane straw samples show higher densities in comparison with bagasse samples. Both lignin samples from bagasse and straw have greater bulk and true density if compared to other materials from sugarcane biomass of cellulosic and lignocellulosic nature. The increase in adsorption pore volume in lignins is observed, being indicative of better sorption ability. Both samples of cellulose and lignocellulose from straw have greater pore structure if compared to the initial material. The values of sodium diclofenac sorption efficiency correlate with the values of pore volume for corresponding materials. Lignin from sugarcane straw, which shows greater porosity, has greater sorption properties. SEM images show that the initial materials and treated materials have complex morphology. FTIR spectra show a clear difference in the structure of lignocellulose, cellulose, and lignin from sugarcane bagasse and straw. The potential application of biopolymers from bagasse and straw as organic carriers of sodium diclofenac was studied. With this purpose, plant polymers were impregnated with an alcoholic solution of sodium diclofenac and the desorption process was investigated. The lignin sample from sugarcane straw has a longer period of drug release, which indicates the obtained effect of prolongation.

This study presents a mass-production process for conductive carbon membrane-type sponge electrodes derived from recyclable cellulose biowaste. It includes an all-in-one hydrogel fabrication process for mass production, which significantly shortens the complex and expensive process for the conventional process of catalytic electrodes based on conductive supporting substrates such as the gas diffusion layer (GDL). The presence of pre-adsorbed melamine powder in the all-in-one hydrogel induces internal diffusion of the gaseous reactant for the uniform growth of carbon nanotubes (CNTs) onto the sponge-like porous carbon aerogel with a relatively thick and tortuous pore structure, thereby providing the electrochemical properties and mechanical strength simultaneously required for the air electrodes of rechargeable and quasi solid-state zinc-air batteries.

Rice straw holocellulose was TEMPO-oxidized and mechanically defibrillated to produce holocellulose nanofibrils (HCNFs) at 33.7% yield (based on original rice straw mass), 4.6% higher yield than cellulose nanofibril (CNF) generated by the same process from pure rice straw cellulose. HCNFs were similar in lateral dimensions (2.92 nm wide, 1.36 nm thick) as CNF, but longer, less surface oxidized (69 vs 85%), and negatively charged (0.80 vs 1.23 mmol/g). HCNFs also showed higher affinity to hydrophobic surfaces than CNFs while still attracted to hydrophilic surfaces. By omitting hemicellulose/silica dissolution step, the two-step 2:1 toluene/ethanol extraction and acidified NaClO2 (1.4%, pH 3-4, 70 °C, 6 h) delignification process for holocellulose was more streamlined than that of pure cellulose, while the resulting amphiphilic HCNFs were more hydrophobic and self-assembled into much finer nanofibers, presenting unique characteristics for new potential applications.

BackgroundThe filamentous fungus Neurospora crassa efficiently utilizes plant biomass and is a model organism for genetic, molecular and cellular biology studies. Here, a set of 567 single-gene deletion strains was assessed for cellulolytic activity as compared to the wild-type parental strain. Mutant strains included were those carrying a deletion in: (1) genes encoding proteins homologous to those implicated in the Saccharomyces cerevisiae secretion apparatus; (2) genes that are homologous to those known to differ between the Trichoderma reesei hyper-secreting strain RUT-C30 and its ancestral wild-type strain; (3) genes encoding proteins identified in the secretome of N. crassa when cultured on plant biomass and (4) genes encoding proteins predicted to traverse the secretory pathway.ResultsThe 567 single-gene deletion collection was cultured on crystalline cellulose and a comparison of levels of secreted protein and cellulase activity relative to the wild-type strain resulted in the identification of seven hyper-production and 18 hypo-production strains. Some of these deleted genes encoded proteins that are likely to act in transcription, protein synthesis and intracellular trafficking, but many encoded fungal-specific proteins of undetermined function. Characterization of several mutants peripherally linked to protein processing or secretion showed that the hyper- or hypo-production phenotypes were primarily a response to cellulose. The altered secretome of these strains was not limited to the production of cellulolytic enzymes, yet was part of the cellulosic response driven by the cellulase transcription factor CLR-2. Mutants implicated the loss of the SREBP pathway, which has been found to regulate ergosterol biosynthesis genes in response to hypoxic conditions, resulted in a hyper-production phenotype. Deletion of two SREBP pathway components in T. reesei also conferred a hyper-production phenotype under cellulolytic conditions.ConclusionsThese studies demonstrate the utility of screening the publicly available N. crassa single-gene deletion strain collection for a particular phenotype. Mutants in a predicted E3 ligase and its target SREBP transcription factor played an unanticipated role in protein production under cellulolytic conditions. Furthermore, phenotypes similar to those observed in N. crassa were seen following the targeted deletion of orthologous SREBP pathway loci in T. reesei, a fungal species commonly used in industrial enzyme production.

KH2PO4, which was manufactured using conversion of KCl and NH4H2PO4, is a concentrated crystalline chlorine-free phosphorus and potassium fertilizer. It is usually used as a component of a liquid complex fertilizer, because KH2PO4 crystals melt very easily, and have very high hygroscopicity and caking effect. Granulated products are considerably more convenient than powders, but KH2PO4 crystals are pure, hardly agglomerate, therefore they need a proper binder. This study aims to investigate the influence of cellulose additive and other different conditions on the granulation process and on the properties of the granulated product. Potassium dihydrogen phosphate was granulated using three different types of granulators (rotary, a fluidized bed and a drum) and by changing the amount of water used for irrigation purposes. The achieved results indicate that in order to obtain granulated potassium dihydrogen phosphate with optimal properties, the use of water does not suffice; therefore, another binder (cellulose) was used in order to improve physical and mechanical properties of the granules. It was determined that cellulose additive (5%) improves some properties of the fertilizer, such as the amount of marketable fraction, SGN, pH, and also reduces the hygroscopicity of the fertilizer granules about 2 times. But cellulose additive does not improve the static strength of granules and bulk density.

Self-assembling of sulfuric-acid-hydrolyzed cellulose nanocrystals (CNCs, 6.4 nm wide) and TEMPO oxidized cellulose nanofibrils (CNFs, 2.1 nm wide) from aqueous suspensions was induced by rapid freezing (-196 °C, 10 min) and slow lyophilization (-50 °C, 0.05 mbar, 2 days). The assembled structures contain submicron (200-700 nm) wide and tens of micrometer long fibers at up to 0.1-0.5% and 0.01-0.05%, the critical fiber-to-film transformation concentrations for CNCs and CNFs, respectively. The assembled fiber widths were significantly reduced to ∼40 nm, that is, by 1 order of magnitude, when 10% of the aqueous media was replaced with tert-butanol. Further increasing tert-butanol contents in the media to 93/7 (CNCs) and 50/50 (CNFs) tert-butanol/water, both at 0.1% nanocellulose concentration, reduced longitudinal assembling for CNCs and lateral assembling for CNFs as well as increased critical fiber-to-film transformation concentration for CNFs. While all assembled structure could be redispersed in water, those from tert-butanol/water could also be easily redispersed in DMF aided with brief 2 min ultrasonication. None of the assembled structures could be redispersed in the lower dielectric constant ethanol, acetone or chloroform.

This is the first report on surface structural elucidation of individual nanocellulose as colloidal suspensions by 1D 1H, 2D heteronuclear single quantum coherence (HSQC) as well as 13C nuclear magnetic resonance (NMR). 1H NMR of rice straw CNCs (4.7 nm thick, 143 nm long, 0.04 sulfate per AG or 19.0% surface hydroxyl to sulfate conversion) resembled that of homogeneous cellulose solution. Conventional 2D HSQC NMR of CNC, CNF 1.5 (2-14 nm thick, several micrometers long, 0.10 COOH per AG) and CNF10 (2.0 nm thick, up to 1 μm long, 0.28 COOH per AG) gave H1:H2 ratios of 1.08:1, 0.97:1 and 0.94:1, respectively, all close to the theoretical 1:1 value for cellulose. The H1:H6 ratios determined from 2D HSQC NMR for CNCs, CNF1.5 and CNF10 were 1:1.47, 1:0.88 and 1:0.14, respectively, and corresponded to 26%, 56% and 93% C6 primary hydroxyl conversion to sulfate and carboxyl groups, consistent with, but more sensitive than those by conductometric titration and X-ray diffraction. Both 1H and 2D HSQC NMR data confirm that solution-state NMR detects nanocellulose surface carbons and protons primarily, validating this technique for direct surface characterization of nanocellulose in aqueous colloidal suspensions, presenting a sensitive and meaningful NMR tool for direct characterizing individual nanocellulose surfaces in never-dried state.

Lithium-ion batteries (LIBs) are favorable power source devices at the last two decades, owing to high energy density, rechargeable, long life cycle, portable, safe, rechargeable, good performance and friendly environment. To support their development, in this research has been successfully prepared polymer electrolyte membrane, a main component of LIBs, based on 1-ethyl-3-methylimidazolium acetate ([EMIm]Ac) ionic liquid-plasticized methyl cellulose/lithium perchlorate (MC/LiClO4). [EMIm]Ac ionic liquid was easy synthesized by metathesis reaction between 1-ethyl-3-methylimidazolium bromide ([EMIm]Br) ionic liquid and potassium acetate (CH3COOK) at ambient temperature, for 1 hour. [EMIm]Ac ionic liquid was functional groups analyzed with Fourier Transform Infra-red (FT-IR) and structural analyzed with 1H-Nuclear Magnetic Resonance (NMR) and 13C-NMR. [EMIm]Ac ionic liquid-plasticized MC/LiClO4 biopolymer electrolyte membrane was prepared by casting solution, with [EMIm]Ac ionic liquid content, 0, 5, 10, 15, 20, 25, and 30% (w/w). Effect of 15% (w/w) [EMIm]Ac ionic liquid incorporation to MC/LiClO4 showed the best condition and selected as the optimum condition with conductivity, tensile strength, elongation break, and thermal stability of 9.160×10-3 S.cm-1, 24.19 MPa, 36.43%, ~256 and ~370 ºC, respectively. These results confirm that [EMIm]Ac ionic liquid can plasticize biopolymer electrolyte membranes of MC/LiClO4 to be appealing performances to fulfill the LIB’s separator requirement. Copyright © 2019 BCREC Group. All rights reserved

In this study, a polymer separator with enhanced thermal stability is prepared to solve the problem of thermal durability of lithium-ion battery separators. This separator is manufactured by coating a solution of acetyl cellulose and glycerin on polypropylene. The added glycerin reacts with the acetyl cellulose chains, helping the chains become flexible, and promotes the formation of many pores in the acetyl cellulose. To improve the thermal stability of the separator, a mixed solution of acetyl cellulose and glycerin was coated twice on the PP membrane film. Water pressure is applied using a water treatment equipment to partially connect the pores of a small size in each layer and for the interaction between the PP and acetyl cellulose. SEM is used to observe the shape, size, and quantity of pores. TGA and FT-IR are used to observe the interactions. Average water flux data of the separators is 1.42 LMH and the decomposition temperature increases by about 60 °C compared to the neat acetyl cellulose. It is confirmed that there is an interaction with PP between the functional groups of acetyl cellulose.

BackgroundSecond-generation biofuels are generally produced from the polysaccharides in the lignocellulosic plant biomass, mainly cellulose. However, because cellulose is embedded in a matrix of other polysaccharides and lignin, its hydrolysis into the fermentable glucose is hampered. The senesced inflorescence stems of a set of 20 Arabidopsis thaliana mutants in 10 different genes of the lignin biosynthetic pathway were analyzed for cell wall composition and saccharification yield. Saccharification models were built to elucidate which cell wall parameters played a role in cell wall recalcitrance.ResultsAlthough lignin is a key polymer providing the strength necessary for the plant's ability to grow upward, a reduction in lignin content down to 64% of the wild-type level in Arabidopsis was tolerated without any obvious growth penalty. In contrast to common perception, we found that a reduction in lignin was not compensated for by an increase in cellulose, but rather by an increase in matrix polysaccharides. In most lignin mutants, the saccharification yield was improved by up to 88% cellulose conversion for the cinnamoyl-coenzyme A reductase1 mutants under pretreatment conditions, whereas the wild-type cellulose conversion only reached 18%. The saccharification models and Pearson correlation matrix revealed that the lignin content was the main factor determining the saccharification yield. However, also lignin composition, matrix polysaccharide content and composition, and, especially, the xylose, galactose, and arabinose contents influenced the saccharification yield. Strikingly, cellulose content did not significantly affect saccharification yield.ConclusionsAlthough the lignin content had the main effect on saccharification, also other cell wall factors could be engineered to potentially increase the cell wall processability, such as the galactose content. Our results contribute to a better understanding of the effect of lignin perturbations on plant cell wall composition and its influence on saccharification yield, and provide new potential targets for genetic improvement.

In this study, wood-based cellulose-rich membranes were produced with a novel approach to casting procedure. Flat-sheet membranes were prepared from birch biomass pretreated with deep eutectic solvent and dissolved in ionic liquid-dimethylsulfoxide system via phase inversion method. Alkaline coagulation bath filled with sodium hydroxide solution was added to the process before a water coagulation bath and aimed to improve membranes’ performance. The effect of NaOH coagulation bath on the membrane was studied based on two NaOH concentrations and two different treatment times. The characterisation methods included measuring pure water permeabilities, polyethylene glycol 35 kDa model solution retentions, hydrophilicity, zeta potential, and chemical structure. Additionally, suitability of the membranes for removing residual phosphorous from a municipal wastewater treatment plant’s effluent was studied. The study revealed that introduction of the alkaline coagulation bath led to additional removal of lignin from membrane matrix and increase in the filtration capacity up to eight times. The resulting membranes can be characterised as very hydrophilic, with contact angle values 11.9–18.2°, negatively charged over a wide pH range. The membranes with the highest permeability, 380–450 L/m2·h·bar, showed approximately 70% phosphorus removal from purified wastewater, good removal of suspended solids, and low irreversible fouling tendency.

To accelerate the high value-added usage of agricultural residue, cellulose and cellulose nanofibers (CNFs) were extracted from wheat straw and then formed into all-cellulose nanocomposite films. The acid–alkali method (AM) and the extraction method (EM) were respectively adopted to prepare wheat straw cellulose (WSC), and the TEMPO oxidation method was used to extract CNFs. The nanocomposite films were fabricated by dissolving WSC and adding different CNF contents of 0.0, 0.5, 1.5, and 3.0%. There was a better miscibility for the all-cellulose nanocomposite film prepared by EM (Composite-E) compared to that for the all-cellulose nanocomposite film prepared by AM (Composite-A). Composite-E also showed a better optical transparency than Composite-A. The thermal stability of the two RWSCs presented contrary results when the CNFs were added, indicating a higher thermal stability for Composite-E than for Composite-A. This should have determined the properties of the films in which Cellulose I and Cellulose II coexisted for the all-cellulose nanocomposite films, and the forming mechanism of Cellulose II and crystallinity were determined by the cellulose-extracting method. X-ray diffraction (XRD) and Fourier-transform infrared (FT-IR) spectroscopy also showed that there was more Cellulose I in Composite-E than in Composite-A. The results are expected to enrich the data for deep processing of agricultural residues.

The work is focused on the study of the influence of the cellulose type and processing parameters on the structure, morphology, and permeability of cellulose films. The free volume of the cellulose films was evaluated by the sorption of n-decane, which is a non-solvent for cellulose. The structural features of the membranes and their morphology were studied using X-ray diffraction, IR spectroscopy, SEM, and AFM methods. The characteristic features of the porous structure and properties of cellulose films regenerated from cellulose solutions in the N-methylmorpholine-N-oxide (NMMO) and cellophane films were compared. Generally, cellulose films obtained from solutions in NMMO have a higher permeability and a lower rejection (as measured using Orange II dye) as compared to cellophane films. It was also found that the cellulose films have a higher ultimate strength and modulus, whereas the cellophane films are characterized by higher elongation at break.

Sawdust is one of the abundantly lignocellulosic materials in the world. Sawdust is considered promosing for ethanol production, because it contains mainly lignin, hemicellulose, and cellulose. The drying process was applied to pretreat sawdust to make its degradation process easier. Biodegradation of sawdust was conducted by enzymatic hydrolysis using cellulase. The volume of cellulase in the hydrolysis substrate was varied from 5 to 9% v/v. The sugar concentration produced by enzymatic hydrolysis of sawdust every 1 h was recorded as well as its fractal kinetics analysis. Fermentation using yeast in 5 days was also performed to convert sugar hydrolysate to ethanol. Optimal sugar concentration in hydrolysate obtained was about 0.15 mol/L with cellulase volume of 9% v/v and its ethanol concentration was about 0.059% v/v. Fractal kinetics models by Kopelman and Valjamae which can quantitatively describe enzymatic hydrolysis of sawdust using cellulase were used. However, the result of this study indicated that, at high enzyme volume (9% v/v), Valjamae model was more suitable than Kopelman. The fractal exponent value (h) was about 0.667 and the rate constants (k) were about 0.44, 0.53, and 0.58 1/h at the enzyme volume of 5, 7, and 9% v/v. Thus, it can be concluded that enzyme volumes significantly effect rate constants.

Olive industry solid waste (OISW) is a by-product generated in the process of olive oil extraction. It is a lignocellulosic material consisting of cellulose, hemicelluloses, lignin and other extractives. In this work, a process for hydrolyzing the OISW into its monomers glucose, the precursor of bioethanol was developed. The hydrolysis process involves two stages: in the first stage, the OISW was activated by treating it with a material that opened the cellulose structure and made it more accessible for chemical reagents. Several activating materials were evaluated among them are water, NaOH, Ca(OH)₂ and acetic acid. In the second stage, the OISW was subjected to an enzymatic treatment which hydrolyzed it into sugar. A combination of the two enzymes cellulase (endo-1,4-β-glucanase) and β-glucosidase was used in the hydrolysis. Best hydrolysis results were obtained at enzymes dose of 15.0 mg of cellulase and 20.0 mg/g of β-glucosidase per one gram of OISW at 45 oC and a pH of 4.8. A yield of 85.02% sugar was obtained from the hydrolysis of 10% NaOH pre-treated OISW under a positive pressure of air. Whereas, hydrolysis of cellulose extracted from OISW by the Kraft pulping process and bleached using DEHP beaching sequence produced about 95.30% sugar.

Simultaneous steam explosion and alkaline depolymerization was studied to develop an economic and green process for alkaline pretreatment of lignocellulose. Steam explosion facilitated alkaline delignification and decreased the amount of alkali used during pretreatment. Different amounts of lignin and hemicellulose were removed within 5 min by using different sodium hydroxide concentrations and steam explosion severity. The main component of lignin collected using our simultaneous process was acid-insoluble lignin, reaching a purity of 84 %. Structural analysis indicated that steam explosion and sodium hydroxide had a synergistic effect on the removal of lignin and hemicellulose from corncob. The effect to four simultaneous pretreatment process of delignification transformed cellulose I to cellulose II, enhancing the enzymatic conversion of cellulose to glucose from 22 % to 96 %. The process of simultaneous steam explosion and alkaline depolymerization shows a potential for application in the lignocellulose biorefinery.

Pd and Co nanoparticles were deposited on cellulose for use as a heterogeneous catalyst in the bimetallic catalytic reduction reaction. The catalyst was characterized with Energy Dispersive X-Ray Spectroscopy, X-Ray Diffraction pattern, Thermal Gravimetric Analysis, Flame Atomic Absorption Spectroscopy, and Transmission Electron Microscopy, and applied in the reduction reaction of nitroaromatics using NaBH4 at room temperature. Aromatic amines were obtained as the sole product of the reduction reaction during 2h. This reaction has some advantages such as mild reaction conditions, high yield, green solvent, and recyclable catalyst. Also, the recovered catalyst is applicable in the reduction reaction for 4 times without a significant decrease in the activity.

Cellulosic ethanol is one the most prominent technologies capable of replacing the use of fossil fuels in an observable horizon of technological development. The complexity of plant biomass, however, continues to challenge our ability to convert it into biofuels efficiently. Highly complex and cross-linked polysaccharides, hydrophobic and protein adsorbent polymers, and crystalline supramolecular structures comprise some of the structures that shield the plant cell contents (and the shield structures themselves) against predators. In response, a sophisticated enzymatic weaponry, with its associated chemical and physical mechanisms, is necessary to overcome this recalcitrance. Here we describe basic information about chemical composition of lignocellulosic biomass and the enzymatic arsenal for lignocellulose deconstruction into fermentable sugars.