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A series of ammonium-based protic ionic liquids, APILs have been synthesized and characterized and their CO2 absorption capacity and potential recyclability have been determined for their potential usein the application of CO2 removal.

Ionic liquids, which are extensively known as low-melting-point salts, have received significant attention as the promising solvent for CO

Black soldier fly larvae (BSFL) have been deployed to valorize various organic wastes. Nonetheless, its growth rate whilst being offered with waste activated sludge (WAS) is not promising, likely by virtue of the presence of extracellular polymeric substances' structure in WAS. In this work, the WAS were first thermally pre-treated under different treatment temperatures and durations before being administered as the feeding substrates for BSFL. The results showed the thermal pre-treatment could improve WAS palatability and subsequently, enhance the growth of BSFL especially after the pre-treatments at 75 °C and above. The highest larva weight gained was recorded at 2.16 mg/larva for the WAS sample being pre-treated at 90 °C and 16 h. Furthermore, the samples pre-treated above 75 °C also achieved higher degradation rates, indicating that the 75 °C was a threshold temperature to effectively hydrolyze the WAS. The changes of WAS characteristics, namely, (i) soluble chemical oxygen demand (SCOD), (ii) soluble carbohydrate, (iii) soluble protein, (iv) humic substances and (v) total soluble protein and humic substances, after the thermal pre-treatments were also studied in correlating with the BSFL growth. Accordingly, a model was successfully developed with the highest R

This work presents an in-depth kinetic thermal degradation comparison between traditional monocationic and the newly developed dicationic ionic liquid (IL), both coupled with a bromide (Br−) anion by using non-isothermal thermogravimetric analysis. Thermal analyses of 1-butyl-1-methylpyrrolidinium bromide [C4MPyr][Br] and 1,4-bis(1-methylpyrrolidinium-1-yl)butane dibromide [BisC4MPyr][Br2] were conducted at a temperature range of 50–650 °C and subjected to various heating rates, which are 5, 10, 15, 20 and 25 °C/min. Thermogravimetric analysis revealed that dicationic IL, [BisC4MPyr][Br2] is less thermally stable compared to monocationic [C4MPyr][Br]. A detailed analysis of kinetic parameters, which are the activation energy (Ea) and pre-exponential factor (log A), was calculated by using Kissinger-Akahira-Sunose (KAS), Flynn-Wall-Ozawa (FWO) and Starink. This study revealed that the average Ea and log A of [BisC4MPyr][Br2] are lower than [C4MPyr][Br], which may be contributed to by its low thermal stability. Conclusively, it proved that the Ea and log A of ILs are strongly related to the thermal stability of ILs.

The special features of metal–organic frameworks (MOFs), namely, tunable porosity, exceptional structure, high surface area and high adsorption capability enable them to be widely studied in many applications including carbon capture and storage (CCS), biomedical engineering, catalysis and pollutant treatment. Despite these remarkable properties, MOFs are known to be moisture-sensitive, hardly recyclable and expensive in fabrication cost which limits their breakthrough performance in more efficient uses. Recently, extensive studies have been devoted to counter those shortcomings by embedding MOFs with support materials using various series of synthetic designs to yield incorporated MOF hybrid materials to counter their limitations. In view of this interest, this review summarizes the latest developments of incorporated MOFs with various materials, namely, ionic liquids (ILs), membranes and metal species. Pre-synthetic and post-synthetic synthesis methods are also discussed. This review also aims to highlight the factors associated with incorporated MOF performance such as materials selection and mass ratio which could have favorable effects in gas separation, catalysis and wastewater treatment applications. The data indicate that incorporated MOF hybrid materials exhibit exceptional properties including excellent robustness and stability. Correspondingly, in comparison to pristine MOFs, incorporated MOF hybrid materials significantly improve, among others, the gas selectivity, catalyst activity and dye removal efficiency in gas separation, catalysis and wastewater treatment, respectively. In addition, the challenge related to the utilization of this newly incorporated material is mentioned.

The dependence on fossil fuel in recent years has accentuated the importance of renewable resources such as biomass. Lignocellulosic biomass consisting mainly of cellulose, hemicellulose, and lignin, can be potentially converted into biochemicals and biofuels. Ionic liquid (IL) has been proven as an efficient and green solvent for biomass dissolution and further processing. Nonetheless, conventionally employed IL treatment requires a longer time and higher temperature making the overall process cost-intensive and time-consuming. The aim of the current research work is to develop a direct probe sonication assisted IL method for rapid biomass dissolution without any external heating. The effect of several experimental parameters on biomass dissolution such as acoustic power (20–60%), sonication time (10–70 min), biomass particle size (500–125 µm), initial sample loading (5, 7.5 and 10%), volume of sample (3, 6 and 9 mL), and types of IL were investigated and optimized. The lignocellulosic biomass and regenerated biomaterials were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, Fourier electron scanning electron microscope, and powder x-ray diffraction to study the effect of probe sonication assisted IL treatment. The ultrasonic cavitation had significantly shortened the time for complete lignocellulose dissolution and considerably altered the thermophysical properties of regenerated cellulose-rich materials. The acetate-based IL showed the best performance, able to fully dissolved bamboo biomass in just 40 min in the probe sonication. In conclusion, probe sonication is an efficient method at lab scale which might need further development in technology to make the process economical at the industrial level for lignocellulosic biomass treatment.

The high investment cost required by modern treatment technologies of hazardous sewage sludge such as incineration and anaerobic digestion have discouraged their application by many developing countries. Hence, this review elucidates the status, performances and limitations of two low-cost methods for biological treatment of hazardous sewage sludge, employing vermicomposting and black soldier fly larvae (BSFL). Their performances in terms of carbon recovery, nitrogen recovery, mass reduction, pathogen destruction and heavy metal stabilization were assessed alongside with the mature anaerobic digestion method. It was revealed that vermicomposting and BSFL were on par with anaerobic digestion for carbon recovery, nitrogen recovery and mass reduction. Thermophilic anaerobic digestion was found superior in pathogen destruction because of its high operational temperature. Anaerobic digestion also had proven its ability to stabilize heavy metals, but no conclusive finding could confirm similar application from vermicomposting or BSFL treatment. However, the addition of co-substrates or biochar during vermicomposting or BSFL treatment may show synergistic effects in stabilizing heavy metals as demonstrated by anaerobic digestion. Moreover, vermicomposting and BSFL valorization had manifested their potentialities as the low-cost alternatives for treating hazardous sewage sludge, whilst producing value-added feedstock for biochemical industries.

Due to the substantial usage of fossil fuels, the utilization of lignocellulosic biomass as renewable sources for fuels and chemical production has been widely explored. The dissolution of lignocellulosic biomass in proper solvents is vital prior to the extraction of its important constituents, and ionic liquids (ILs) have been found to be efficient solvents for biomass dissolution. However, the high viscosity of ILs limits the dissolution process. Therefore, with the aim to enhance the dissolution of lignocellulosic biomass, a series of new ether-functionalized ILs with low viscosity values were synthesized and characterized. Their properties, such as density, viscosity and thermal stability, were analyzed and discussed in comparison with a common commercial IL, namely 1-butyl-3-methylimidazolium chloride (BMIMCl). The presence of the ether group in the new ILs reduces the viscosity of the ILs to some appreciable extent in comparison to BMIMCl. 1-2(methoxyethyl)-3-methylimidazolium chloride (MOE-MImCl), which possesses the lowest viscosity value among the other ether-functionalized ILs, demonstrates an ability to be a powerful solvent in the application of biomass dissolution via the sonication method. In addition, an optimization study employing response surface methodology (RSM) was carried out in order to obtain the optimum conditions for maximum dissolution of biomass in the solvents. Results suggested that the maximum biomass dissolution can be achieved by using 3 weight% of initial biomass loading with 40% amplitude of sonication at 32.23 min of sonication period.

Ionic liquids which are often classified as low melting point salts have received significant attention from research groups and industries to be used in a wide range of applications. Many of these applications require thorough knowledge on the thermophysical properties of the ionic liquids before utilizing their full potentials in various fields. In this work, a series of alkylammonium cation and carboxylate anion-based room temperature protic ionic liquids (PILs) were synthesized by varying length of alkyl chain of the cation from diethyl to dibutyl combined with pentanoate, hexanoate and heptanoate anions. These ammonium-based PILs named as diethylammonium pentanoate [DEA][C5], diethylammonium hexanoate [DEA][C6], diethylammonium heptanoate [DEA][C7], dibutylammonium pentanoate [DBA][C5], dibutylammonium hexanoate [DBA][C6] and dibutylammonium heptanoate [DBA][C7] were characterized using Nuclear Magnetic Resonance (NMR) spectroscopy. The thermophysical properties of the PILs namely density, dynamic viscosity and refractive index were measured and analyzed. Density, &rho, and dynamic viscosity, &eta, were determined at T = (293.15 to 363.15) K and refractive index, nD was measured at T = (293.15 to 333.15) K. The fitting parameters are proposed for the empirical correlations of density, dynamic viscosity and refractive index. The values of thermal expansion coefficient, &alpha, p, molecular volume, Vm, standard entropy, S&deg, and lattice potential energy, Upot also have been calculated by using the specified equations. The thermal decomposition temperature, Td was also determined using a thermogravimetric analyzer (TGA) while the differential scanning calorimetry (DSC) technique provided the glass transition, Tg, melting point, Tm and crystallization, Tc temperatures of the PILs. The experimental results revealed that the dependency of the experimental values namely the &rho, &eta, nD, and Td on the alkyl chain of the anion, size of the cations and the temperature of measurement.

Simultaneous biosorption and bioreduction experienced by Cr(VI) species were initially validated by mixing 500 µM of Cr(VI) with 0.20 g of sawdust biosorbent. Accordingly, a complete disappearance of Cr(VI) species with emergence of 25% of Cr(III) ions was recorded; evidencing that both processes transpired simultaneously. An increase in the initial Cr(VI) concentration to 1500 µM could further induce more reduced Cr(VI) concentration. The enhancement of Cr(VI) biosorption and bioreduction was found to occur upon increasing the sawdust dosage to 4 g L−1 and decreasing the solution pH to 2. However, the presence of a Zn(II) co-pollutant at 2500 µM had deteriorated the removal of Cr(VI) species.

This work compared the effect of soaking and roasting Phoenix dactylifera L. seeds pretreatment methods on oil yield. The conversion of the Phoenix dactylifera L. seed oil to fatty acid methyl ester (FAME) was conducted via transesterification reaction using Ce-Zr/Al-MCM-41 monometallic and bimetallic catalysts. The reaction conditions were optimized using response surface methodology based on the central composite design (RSM-CCD). The result shows a quadratic model fitting with an R2 value of ~0.98% from the analysis of variance. In addition, the optimum FAME yield of 93.83% was obtained at a reaction temperature of 60.5 &deg, C, a reaction time of 3.8 h, a catalyst concentration of 4 wt.%, and a methanol to oil molar ratio of 6.2:1 mol/mol. The effect of the regenerated catalyst was significantly maintained for five cycles. The fuel properties of the produced FAME lie within the values reported in studies, ASTM D6751, and EN14214 standards.

The search of new sustainable energy sources based on renewable biomass feedstocks from lignocellulose biomass constituents namely cellulose, hemicellulose and lignin is a global effort to replace fossil fuel sources. Several conventional methods that have been used for extracting constituents via biomass dissolution include acid and base hydrolyses. However, these processes offer several drawbacks and therefore cannot be considered as environmental-friendly. This study investigates the dissolution of bamboo biomass from species Gigantochloa scortechini in low-viscosity ether-functionalized ionic liquids (ILs) by employing direct probe sonication method. Two ether-functionalized ILs which are MOE-MImCl and MOE-BImCl have been synthesized and characterized and their performance towards biomass dissolution have been tested. Results show that both MOE-MImCl and MOE-BImCl are able to dissolve the biomass with percentage dissolution of 88.1% and 28.1%, respectively with 20 minutes dissolution time. FTIR analyses were also done on both untreated biomass and regenerated biomass. The recyclability of the ILs for dissolving biomass was also tested and results show that the percentage of biomass dissolved in the recycled ILs reduce by approximately 10% of the original values.

Ionic liquids (ILs) have been proven to be one of effective approaches for biomass dissolution. In this work, direct bamboo biomass dissolution in IL under probe sonication technique was studied. An ether-functionalized IL was synthesized and used in this study. Dissolution of biomass was observed under microscope. It was found that the presence of ether group in the IL decreased time up to 60% for complete biomass dissolution as compared to non-functionalized IL. Regenerated cellulose rich materials (CRM) recovered from both ether and non-functionalized IL treatment were characterized using FTIR, SEM and TGA. Regenerated biomass showed slight reduction on thermal stability following dissolution.

In this study, four ammonium-based ionic liquids were synthesized and characterized for carbon dioxide (CO2) removal from natural gas. All ionic liquids (ILs) were synthesized using one-step neutralization reaction. The density, viscosity, 1H-NMR purity analysis and thermal decomposition of the ILs were determined. CO2 absorption of ethanolammonium butyrate [EtOHA][BA], which have the highest decomposition temperature was measured and analyzed at pressure, P ranging from 1 to 29 bar and at three different temperatures, T = 298.15K, 313.15K and 323.15K. The highest CO2 absorption of [EtOHA][BA] is at 323.15K, 29 bar which is 0.35 mol fraction.

This work presents a molecular level investigation on the nature and mode of binding between imidazolium-based ionic liquids (ILs) ([Cnbim]Br where n = 2, 4, 6) with calf thymus DNA. This investigation offers valuable insight into the mechanisms of interactions that can affect the structural features of DNA and possibly cause the alteration or inhibition of DNA function. To expedite analysis, the study resorted to using molecular docking and COnductor like Screening MOdel for Real Solvents (COSMO-RS) in conjunction with fluorescence spectroscopic data for confirmation and validation of computational results. Both the fluorescence and docking studies consistently revealed a weak interaction between the two molecules, which corresponded to the binding energy of a stable docking conformation in the range of &minus, 5.19 to &minus, 7.75 kcal mol&minus, 1. As predicted, the rod-like structure of imidazolium-based ILs prefers to bind to the double-helix DNA through a minor groove. Interestingly, the occurrence of T-shape &pi, &pi, stacking was observed between the amine group in adenine that faces the aromatic ring of imidazole. In addition, data of COSMO-RS for the interaction of individual nucleic acid bases to imidazolium-based ILs affirmed that ILs showed a propensity to bind to different bases, the highest being guanine followed by cytosine, thymine, uracil, and adenine.

Ionic liquids, which are classified as new solvents, have been identified to be potential solvents in the application of CO2 capture. In this work, six ammonium-based protic ionic liquids, containing ethanolammonium [EtOHA], tributylammonium [TBA], bis(2-ethylhexyl)ammonium [BEHA] cations, and acetate [AC] and butyrate [BA] anions, were synthesized and characterized. The thermophysical properties of the ammonium-based protic ionic liquids were measured. Density, , and dynamic viscosity, , were determined at temperatures between 293.15 K and 363.15 K. The density and viscosity values were correlated using empirical correlations and the thermal coefficient expansion, p, and molecular volume, Vm, were estimated using density values. The thermal stability of the ammonium-based protic ionic liquids was investigated using thermogravimetric analyzer (TGA) at a heating rate of 10 C.min‒1. The CO2 absorption of the ammonium-based ionic liquids were measured up to 20 bar at 298.15 K. From the experimental results, [BEHA][BA] had the highest affinity towards CO2 with the mol fraction of CO2 absorbed approaching 0.5 at 20 bar. Generally, ionic liquids with butyrate anions have better CO2 absorption than that of acetate anions while [BEHA] ionic liquids have higher affinity towards CO2 followed by [TBA] and [EtOHA] ionic liquids.

Ionic liquids are new alternative solvents that can be used to separate carbon dioxide in the gas separation process. However, the high viscosity of ionic liquids limits the mass transfer of solutes into ionic liquids. In this work, 1-hexyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide ([hmi [Tf2) was impregnated onto porous Al2O3 and SiO2 and tested for CO2 adsorption at pressure up to 40 bar at 25 °C. The screening process showed that [hmi [Tf2-Si gave higher CO2 adsorption capacity compared to [hmi [Tf2-Al and pure [hmi [Tf2. The experimental work was further investigated by varying the composition of [hmi [Tf2 inside SiO2 pores. The composition of [hmi [Tf2 was varied from 10 wt% to 40 wt%. The result showed the 10 wt% composition gave the highest CO2 adsorption compared to 20 wt%, 30 wt% and 40 wt%. The lower CO2 adsorption by 20 wt%, 30 wt% and 40 wt% might be due to the blockage of SiO2 pores by excess [hmi [Tf2. From this research, it proved that porous solid support can provide high surface area that is necessary to accommodate intimate contact between CO2 and solid supported ionic liquid and increases the CO2 adsorption capacity.

Solid supported ionic liquids can be used to overcome the high viscosity issue of ionic liquids and help increase the efficiency of CO2 removal. In this research, [hmi [Tf2 was impregnated into porous silica dioxide (SiO2) and characterized using Porous and Surface Analyzer, Thermogravimetric Analysis (TGA) and Spectroscopy RAMAN. The CO2 solubility was measured at different pressure at room temperature. The mole fraction of CO2 captured was increased as the pressure increased, and the highest mole fraction was at 40 bar. The mole fraction of CO2 captured at 40 bar for SiO2-[hmi [Tf2 was 0.812 which was higher compared to pure [hmi [Tf2, with mole fraction of 0.650. Henrys Law Constant (KH) was higher for SiO2-[hmi [Tf2 with 26.8±5.2 bar while for [hmi [Tf2, the KH was 35.4±3.3 bar.

Lignin, a heterogenous polymer which presents about 20-30 % in lignocellulose emerged as promising feedstock for the production of specialty chemicals. However, due to lignocellulose recalcitrance structure, the pretreatment is necessary to obtain efficient utilization of biomass. In this work, the preliminary study was carried out focusing on the properties lignin extracted from bamboo (Gigantochloa scortcheninii) using alkali and ionic liquid pretreatment. It was discovered that about 42% and 11% of acid-insoluble lignin has been extracted from alkali and IL pretreatment respectively. The degradation onset temperature of alkali and ionic liquid extracted lignin were found to be 262.20 and 172.41°C. FTIR spectra analysis showed the characteristic peaks of lignin for both samples. Desirable products such as aldehydes, phenol, hydrocarbons and aromatics were identified from pyrolysis GC-MS

The thermophysical properties of 1-alkylpyridinium bis(trifluoromethylsulfonyl)imide, [C n py][Tf 2 N] ionic liquids where n = 4, 8, 10, or 12 have been determined. Density ρ , and dynamic viscosity η , were determined at T = (293.15 to 353.15) K and refractive index n D , was measured at T = (293.15 to 333.15) K. Empirical correlations are proposed to represent the present experimental results. The values of the coefficient of thermal expansion were calculated from the experimental density values. The thermal decomposition temperature, T d was also determined using thermogravimetric analyzer (TGA) at a heating rate of (10 and 20) K · min −1 .

Reliable predictive methods for estimating experimental results over wide range of operating conditions are useful and highly desirable. In this paper, the solubility of CO2 in 1-butylpyridinium bis(trifluoromethylsulfonyl)imide, [C4py][Tf2N] and 1-dodecylpyridinium bis(trifluoromethylsulfonyl)imide, [C12py][Tf2N] ionic liquids have been measured experimentally via gravimetric method using Magnetic Suspension Balance instrument at 298.15K and in the pressures range up to approximately 30 bar. The solubility data was fitted using an activity coefficient model i.e UNIQUAC model. The interaction parameters of the model were estimated. The predicted CO2 solubility data by the model shows good agreement with the experimental data.

The alkaline and water soluble polysaccharides were isolate by sequential extractions with distilled water, 60% ethanol containing 1%, 5% and 8% NaOH. The samples were prepared at 60 °C for 3 h from local bamboo. The functional group of the sample were examined using FTIR analysis. The most precipitate obtained is from using 60% ethanol containing 8% NaOH with yield of 2.6%. The former 3 residues isolated by sequential extractions with distilled water, 60% ethanol containing 1% and 5% NaOH are barely visible after filtering with cellulose filter paper. The FTIR result showed that the water-soluble polysaccharides consisted mainly of OH group, C H group, C O indicates the carbohydrate and sugar chain. The sample weight loss was slightly decreased with increasing of temperature.

The solubility of CO2 in 1-butylpyridinium bis(trifluoromethylsulfonyl)imide [C4py][Tf2N] ionic liquid has been determined using Magnetic Suspension Balance instrument at 298.15 K and in the pressures up to about 27 bar. A group contribution method, namely UNIFAC has been used to fit the experimental data. The interaction parameters of the model were estimated. The predicted CO2 solubility data by the model shows good agreement with the experimental data.