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Membrane separation processes find applications in an array of fields as they use far less energy and chemical agents than competing processes. However, a major drawback of membrane technology is that biofilm formation alters membrane performances. Preventing biofilm formation is thus a pivotal challenge for larger-scale development of membrane processes. Here, we studied the comparative antibacterial activities of different inorganic membranes (ceramic and zeolite-coated ceramic with or without copper exchange) using several bacterial strains ( Escherichia coli, Staphylococcus aureus, and Bacillus subtilis). In static conditions, alumina plates coated with Cu-exchanged zeolite showed significant bactericidal activity. In dynamic mode (circulation of a contaminated nutrient medium), there was no observable bacterial adhesion at the surface of the Cu-exchanged material. These results confirm the antifouling properties of the Cu-mordenite layer due to both the increased hydrophilicity and antibacterial properties of the active layer. Tests performed with tubular filtration membranes (without copper exchange) showed a significant decline in membrane hydraulic properties during filtration of culture media containing bacteria, whereas copper-exchanged membranes showed no decline in hydraulic permeability. Filtration tests performed with concentrated culture media containing spores of B. subtilis led to a significant decrease in membrane hydraulic permeabilities (but less so with Cu-exchanged membranes). The surfaces showed less effective global antifouling properties during the filtration of a concentrated culture medium due to competition between bacterial growth and the bactericidal effect of copper. Analyses of copper leached in solution show that after a conditioning step, the amount of copper released is negligible. [ABSTRACT FROM AUTHOR]

The thermal degradation characteristics ofPosidonia Oceanica(PO), a marine biomass abundantly available on the coastal zone of the Mediterranean Basin, were investigated using thermogravimetric analysis under inert and oxidative atmospheres. The kinetic parameters of the both thermal degradations conditions were determined usingn-reaction order model. Coats–Redfern and Phadnis–Deshpande methods were used to discuss the probable degradation mechanisms. Results showed that PO is an attractive alternative for energy production owing to its elevated heating value. Moreover, PO thermal degradation follows the usual shape of biomass decomposition. Hence, under inert atmosphere, its thermal degradation had two different stages after moisture release. The first stage corresponded to the volatiles release while the second stage corresponded to the char formation. The solid-state decomposition mechanisms followed by the devolatilization step of PO were two or three dimensional diffusion controlled reaction. However, the decomposition mechanism during PO char formation corresponded to a nucleation and growth mechanism. Under oxidative atmosphere, two stages were also observed corresponding to volatiles release and char combustion, respectively. The solid-state mechanism of volatiles release followed three dimensional diffusion controlled reaction while the char combustion mechanism corresponded to a contracting area phase boundary controlled reaction. [ABSTRACT FROM AUTHOR]

Nanofiltration is a membrane process which is used to separate charged molecules such as ions. Even if this process is well known, there is no mean to predict the performances of a given separation. The aim of this paper is to present a two-dimensional model called 'pore and polarization transport model' which includes all the steps of the ions transfer. The membrane transport modeling is based on the classical one-dimensional vision coupling the Donnan, steric, and dielectric exclusions with the extended Nernst-Planck transport equation. But the originality of this study comes from the modeling of the transport through the polarization layer. The model used in this study is an improvement of the previous version, which includes an electrical gradient within the polarization layer allowing the prediction of polarization layer establishment even for ionic mixtures. The purpose of this article is to describe the model accurately before validating it with various ionic solutions. © 2010 American Institute of Chemical Engineers AIChE J, 2011 [ABSTRACT FROM AUTHOR]

This study has an important impact on gasoline engine-pollution control working under lean conditions. While NOx trap systems can remove NOx under an oxidative atmosphere, they are poisoned by SOx present in the exhaust gases. In order to protect NOx traps, an upstream SOx trap has to be used. SO2 adsorption was studied in the presence of water and oxygen. Model and commercial catalysts were tested between 300 and 700 °C. In order to assign the TPD peaks, the decomposition of commercial sulphates was studied versus the temperature. Adsorption capacity is not sensitive to oxygen and SO2 concentrations but is strongly related to barium content. Cerium content is not a key parameter for SO2 adsorption capacity in the presence of oxygen. XPS analysis allowed us to differentiate between all the species formed during the adsorption process. When the catalysts are aged, specific surface area decreases as well as adsorption capacity. [Copyright &y& Elsevier]

Abstract: Commercial ceramic low cut-off (1kDa) ultrafiltration TiO2 membrane behavior is studied in the presence of single salt solutions (NaCl and MgCl2: 5.10−2 M). Surface property characterizations of the membrane layer are carried out on TiO2 powder. Zetametry and streaming induced potential experiments show that the isoelectric point of TiO2 remains stable in the presence of NaCl, while it shifts to a higher pH value in the presence of MgCl2. At native pH (close to 7), the adsorption of Mg2+ on TiO2 surface leads to an inversion of the surface charge (negative to positive) and to an important increase of the surface charge density. Filtration tests are carried out on a laboratory pilot using NaCl and MgCl2 5.10−2 M solutions. Contrary to the sodium chloride solution, retentions of MgCl2 solution show some peculiarities. First, the permeation flux of pure water decreases after each experimental test in an irreversible way. Second, in particular conditions, the adsorption equilibriums are reached after several days, which significantly affect membrane performances. Finally, punctual pH modification (acid or basic) affects the surface charge of the active layer and thus the retentions of magnesium chloride, but the amphoteric behavior of the TiO2 surface tends to bring back the pH to the initial value. [Copyright &y& Elsevier]

The growing energy consumption and the need for a circular economy have driven considerable interest in the anaerobic digestion (AD) of organic waste, offering potential solutions through biogas and digestate production. AD processes not only have the capability to reduce greenhouse gas emissions but also contribute to the production of renewable methane. This comprehensive review aims to consolidate prior research on AD involving different feedstocks. The principles of AD are explored and discussed, including both chemical and biological pathways and the microorganisms involved at each stage. Additionally, key variables influencing system performance, such as temperature, pH, and C/N ratio are also discussed. Various pretreatment strategies applied to enhance biogas generation from organic waste in AD are also reviewed. Furthermore, this review examines the conversion of generated digestate into biochar through pyrolysis and its utilization to improve AD performance. The addition of biochar has demonstrated its efficacy in enhancing metabolic processes, microorganisms (activity and community), and buffering capacity, facilitating Direct Interspecies Electron Transfer (DIET), and boosting CH 4 production. Biochar also exhibits the ability to capture undesirable components, including CO 2 , H 2 S, NH 3 , and siloxanes. The integration of digestate-derived biochar into the circular economy framework emerges as a vital role in closing the material flow loop. Additionally, the review discusses the environmental benefits derived from coupling AD with pyrolysis processes, drawing on life cycle assessment investigations. Techno-economic assessment (TEA) studies of the integrated processes are also discussed, with an acknowledgment of the need for further TEA to validate the viability of integrating the biochar industry. Furthermore, this survey examines the techno-economic and environmental impacts of biochar production itself and its potential application in AD for biogas generation, aiming to establish a more cost-effective and sustainable integrated system.

In the context of sustainable solutions, this study examines the pyrolysis process applied to corn cobs, with the aim of producing biochar and assessing its effectiveness in combating air pollution. In particular, it examines the influence of different pyrolysis temperatures on biochar properties. The results reveal a temperature-dependent trend in biochar yield, which peaks at 400 °C, accompanied by changes in elemental composition indicating increased stability and extended shelf life. In addition, high pyrolysis temperatures, above 400 °C, produce biochars with enlarged surfaces and improved pore structures. Notably, the highest pyrolysis temperature explored in this study is 600 °C, which significantly influences the observed properties of biochars. This study also explores the potential of biochar as an NO 2 adsorbent, as identified by chemical interactions revealed by X-ray photoelectron spectroscopy (XPS) analysis. This research presents a promising and sustainable approach to tackling air pollution using corn cob biochar, providing insight into optimized production methods and its potential application as an effective NO 2 adsorbent to improve air quality.

Heat storage technologies are essential for increasing the use of solar energy in the household sector. Their development can be achieved by designing new storage materials; one way is to impregnate a porous matrix with hygroscopic salts. In this article, the possibility of using biochar-based composite sorbents to develop promising new heat storage materials for efficient thermal storage is explored. Biochar-based composites with defined salt loadings (5, 10, 15, and 20%) were produced by impregnating MgSO 4 into a biochar matrix derived from corn cobs. The new materials demonstrated a high water sorption capacity of 0.24 g/g (20MgCC). After six successive charging-discharging cycles (dehydration/dehydration cycles), only a negligible variation of the heat released and the water uptake was measured, confirming the absence of deactivation of 20MgCC upon cycling. The new 20MgCC composite showed an energy storage density of 635 J/g (Tads = 30 °C and RH = 60%), higher than that of other composites containing a similar amount of hydrate salt. The macroporous nature of this biochar increases the available surface for salt deposition. During the hydration step, the water molecules effectively diffuse through a homogeneous layer of salt, as described by the intra-particle model applied in this work. The new efficient biochar-based composites open a low-carbon path for the production of sustainable thermal energy storage materials and applications.

Tomato pomace was slowly pyrolyzed at 350 and 550 °C (under an N 2 flow of 50 L/h) at a rate of 6 °C/min and a residence time of 1:30 h to produce two biochars named B350 and B550, respectively. In addition, the two biochars were chemically activated with ΚΟΗ (at a ratio of 1:10 w/v) at 800 °C to produce two new materials named BA350 and BA550. The four biochars produced were characterized physically and chemically (pH, yield, calorific value). They were also analyzed by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (B.E.T), elemental analysis (EA), and thermogravimetric analysis (TGA). The results showed that as the pyrolysis temperature increased (350 to 550 °C), the specific surface area (SSA) increased. The latter was also significantly increased by the activation process. EA showed a variation in the mineral content of the produced biochars, resulting in a different content of the biochars after activation. The parameters studied showed that biochars from tomato waste could be used as an organic amendment to improve soil fertility in agricultural. In addition, because of their ability to absorb water, they could be used as a water reservoir in soils in arid areas., Competing Interests: Declaration of competing interest The authors have no competing interests to declare that are relevant to the content of this article., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Studies on the immobilization of oxindolimine‑copper(II) or zinc(II) complexes [ML] in synthetic beidellite (BDL) clay were developed to obtain a suitable inorganic carrier capable of promoting the modified-release of metallopharmaceuticals. Previous investigations have shown that the studied metal complexes are promising antitumor agents, targeting DNA, mitochondria, and some proteins. They can bind to DNA, causing oxidative damage via formation of reactive oxygen species (ROS). In mitochondria they lead to a decrease in membrane potential, acting as decoupling agents, and therefore efficiently inducing apoptosis. Additionally, they inhibit human topoisomerase IB and cyclin dependent kinases, proteins involved in the cell cycle. BDL clays in the sodium form were synthesized under hydrothermal conditions and characterized by a set of physicochemical techniques while the BDL-[ML] hybrid materials were prepared by ion exchange method. The characterization of pristine clay and the obtained hybrids were performed by Infrared, Raman, electron paramagnetic resonance and energy dispersive X-ray spectroscopies, thermogravimetric analysis, scanning electron microscopy, X-ray powder diffraction, specific surface area, zeta potential and surface ionic charge measurements. The [ML] release assays under the same cell incubation conditions were performed monitoring metals by X-ray fluorescence. The BDL-[CuL] hybrid materials were stable and able to derail tumor HeLa cells, with corresponding IC 50 values in the 0.11-0.41 mg mL -1 range. By contrast, the analogous hybrid samples of zinc(II) and the pristine BDL proved to be non-toxic facing the same cells. These results indicate a promising possibility of using synthetic beidellite as a carrier of such antitumor metal complexes., Competing Interests: Declaration of Competing Interest The University of São Paulo (USP) has a Brazilian patent (BR PI 0600985–9 conceded on March 24th, 2020 – INPI Brazil) based on the oxindolimine-metal complexes with antitumor activity, prepared and investigated at Da Costa Ferreira's lab, at Institute of Chemistry - USP. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ana Maria da Costa Ferreira reports administrative support was provided by AUSPIN - Agencia USP de Inovação (University of São Paulo Innovation Agency). Ana Maria da Costa Ferreira reports a relationship with AUSPIN - Agencia USP de Inovação (University of São Paulo Innovation Agency) that includes: non-financial support. Ana Maria da Costa Ferreira has patent #Brazilian patent (BR PI 0600985-9 conceded on March 24th, 2020 – INPI Brazil) issued to non licensee or assignee., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The present study investigates the potential of waste tires to produce a valuable adsorbent material for application in wastewater treatment. In the first stage, the pyrolysis of ground rubber tire was explored using non-isothermal and isothermal thermogravimetric analysis experiments. The effect of operating parameters, such as heating rate and pyrolysis temperature, on the pyrolysis product yields was considered. The slow pyrolysis of ground rubber tire was taken up in a large-scale fixed-bed reactor for enhanced char recovery. Four pyrolysis temperatures were selected by thermogravimetric data. The product yields were strongly influenced by the pyrolysis temperature; at higher temperatures, the formation of more gases and liquid was favored, while at lower pyrolysis temperatures, more char (solid fraction) was formed. The produced chars were characterized in terms of mineral composition, textural properties, proximate analysis, and structural properties to identify the relationships between the pyrolysis temperature and the char properties. In a second step, a series of activated chars were prepared, starting from the pyrolytic chars via chemical and/or physical activation methods. Then, the activated chars were characterized and tested as adsorbents for atrazine and ibuprofen. Adsorption experiments in aqueous media were carried out in a small-scale batch reactor system. Chemical activation seems appropriate to significantly reduce the inorganic compounds initially present in ground rubber tire and contribute to an important increase in the surface area and porosity of the chars. Adsorption experiments indicated that chemically activated chars exhibit high aqueous adsorption capacity for atrazine.

Advanced oxidation processes are considered as a promising technology for the removal of persistent organic pollutants from industrial wastewaters. In particular, the heterogeneous electro-Fenton (HEF) process has several advantages such as allowing the working pH to be circumneutral or alkaline, recovering and reusing the catalyst and avoiding the release of iron in the environment as a secondary pollutant. Among different iron-containing catalysts, studies using clay-modified electrodes in HEF process are the focus in this review. Fe(III)/Fe(II) within the lattice of clay minerals can possibly serve as catalytic sites in HEF process. The description of the preparation and application of clay-modified electrodes in the degradation of model pollutants in HEF process is detailed in the review. The absence of mediators responsible for transferring electrons to structural Fe(III) and regenerating catalytic Fe(II) was considered as a milestone in the field. A comprehensive review of studies investigating the use of electron transfer mediators as well as the mechanism behind electron transfer from and to the clay mineral structure was assembled in order to uncover other milestones to be addressed in this study area.

Human activities are considered among the main producers of any kind of pollution. This paper, through a Driver-Pressure-State-Impact-Response (DPSIR) model analyses, focuses on the evaluation and assessment of the existing practices, procedures, and results obtained in order to determine whether the municipal solid waste (MSW) management implemented in three major Greek municipalities in the greater urban area of Attica, namely the municipalities of Nea Smirni, Vyronas, and Piraeus, could be considered viable and sustainable. The evaluation indicated that MSW in Greek cities have reduced over the last years, also suggesting a steady downward trend, which could be considered consistent with that of the per capita incomes in Greece due to the extended economic austerity, while at the same time the recycling indicator seems to optimize. The results are very useful for policymakers and local authorities towards taking actions related to the targets set from the circular economy strategies as well as the targets set from United Nation Development Program and the European Green Deal Strategy.

Olive mill wastewater (OMW) is nowadays considered as a serious source pollution. At the same time, it contains high amounts of nutrients, especially potassium and phosphorus that could be recovered for agricultural purposes. The aim of the current experimental research work is to investigate the agronomic potential use of OMW based biochar produced from the slow pyrolysis at 500 °C of raw cypress sawdust (CS) impregnated with OMW (ICS-OMW-B). In order to understand the contribution of OMW, two additional biochars were produced from raw cypress sawdust (RCS-B) and cypress sawdust pretreated with potassium chloride (ICS-K-B). Results indicated that RCS impregnation by OMW significantly improved the produced biochar's chemical properties, especially its nutrients contents. Furthermore, in comparison with the other biochars, ICS-OMW-B application as an organic fertilizer showed promising results in terms of produced fresh and dry masses, as well as potassium bioavailability as assessed in test experiments with ryegrass. For instance, the dry matter masses of the rye-grass treated with ICS-OMW-B were about 23, 34 and 50 wt% higher than the ones measured for the tests using RCS-B, ICS-K-B and synthetic K-fertilizer as amendments, respectively. Besides, this biochar has a potential effect on the suppression of various pathogens existing in the tested agricultural soil. All these results demonstrated that the biochar generated from the slow pyrolysis of impregnated sawdust with OMW could be considered as attractive and promising organic fertilizer for acidic agricultural soils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Ni-Co-Al, Ni-Cu-Al and Co-Cu-Al ternary oxide catalysts, with a fixed 5 wt% transition metal loading, were prepared by the microwave-assisted solution combustion method and tested in CO oxidation. The bulk and surface properties of the catalysts were investigated, using XRD, N 2 adsorption-desorption, SEM, XPS and TEM techniques. XRD, XPS and TEM results revealed that nickel and cobalt were present as spinels on the surface and in the bulk. Differently, copper was preferentially present in "bulk-like" CuO-segregated phases. No interaction between the couples of transition metal species was detected, and the introduction of Cu-containing precursors into the Ni-Al or Co-Al combustion systems was not effective in preventing the formation of NiAl 2 O 4 and CoAl 2 O 4 spinels in the Ni- or Co-containing catalysts. Copper-containing catalysts were the most active, indicating that copper oxides are the effective active species for improving the CO oxidation activity.

In this study, we report the production of a free-standing film of non-modified cellulose impregnated with 12 wt.% of MnO 2 nanoparticles with less than 100 nm in size. The method here described can be applied to the immobilization of different types of nanoparticles. The film was prepared by dissolving microcrystalline cellulose in an ionic liquid followed by its regeneration by adding water to the former solution. Then, the wet film was impregnated with the nanoparticles by dipping it in a MnO 2 dispersion. Electron microscopy images revealed manganese dioxide nanoparticles distributed not only at the film surface but also in its interior. The cellulose film impregnated with MnO 2 nanoparticles was capable of efficiently discolouring an Indigo Carmine dye solution in 25 min upon ambient light. The film was easily removed from the dye solution and repeatedly reused for at least 10 times without losing its discolouring efficiency., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In this study, silylated Laponites ® (LAP) were synthetized with various loads of 3-aminopropyltriethoxysilane (APTES) to evaluate their adsorption properties of 133 Cs, 59 Co, and 88 Sr during single-solute and competitive experiments. The increase in the initial load of APTES increased the adsorbed amount of APTES in the resulted grafted clay. The characterization of LAP-APTES exhibited a covalent binding between APTES and LAP and emphasized the adsorption sites of APTES for each tested load. In comparison with raw LAP, LAP-APTES displayed significantly higher adsorption properties of Co 2+ , Cs + , and Sr 2+ . The competitive adsorption of these three contaminants provides a deeper understanding of the affinity between adsorbate and adsorbent. Therefore, Co 2+ displayed a strong and specific adsorption onto LAP-APTES. Except for Cs + , the adsorption capacity was improved with increasing the load of APTES. Finally, the desorption behavior of the three contaminants was tested in saline solutions. Cs + and Sr 2+ were significantly released especially by inorganic cations displaying the same valence. Conversely, desorption of Co 2+ was very low whatever the saline solution. LAP-APTES, therefore, presented suitable adsorption properties for the removal of radionuclides especially for Co 2+ , making this material suitable to improve the decontamination of radioactive wastewaters., Competing Interests: The authors declare no conflicts of interest.

The energy industry (nuclear, battery, mining industries, etc.) produces a large quantity of hazardous effluents that may contain radionuclides ( 137 Cs and 90 Sr in particular) and heavy metals. One of the hardest tasks of environmental safety and sustainable development is the purification of wastewater holding these pollutants. Adsorption is one of the most powerful methods for extracting toxic compounds from wastewater. This study reviews the usefulness of clay minerals as adsorbent for removing these hazardous elements to clean up energy production processes. Phyllosilicates are able to extract several heavy metals from effluent, as widely examined. A particular focus is given to synthetic phyllosilicates and their abilities to entrap heavy metals with a special attention paid to those synthesized by sol-gel route. Indeed, this method is attractive since it allows the development of organic-inorganic hybrids from organosilanes presenting various functions (amino, thiol, etc.) that can interact with pollutants. Regarding these pollutants, a part of this review focuses on the interaction of lamellar materials (natural and synthetic phyllosilicates as well as layered double hydroxide) with heavy metals and another part deals with the adsorption of specific radionuclides, cesium and strontium., Competing Interests: The authors declare no conflict of interest.