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World production of dyes is estimated at more than 800,000 t·yr−1. The purpose of this research falls within the scope of the choice of an effective, local, and inexpensive adsorbent to remove dyes from wastewater. Adsorptive elimination of dyes by commonly accessible adsorbents is inefficient. The metal–organic frameworks (MOFs) are an important class of porous materials offering exceptional properties as adsorbents by improving separation efficiency compared to existing commercial adsorbents. However, its powder form limits its applications. One way to overcome this problem is to trap them in a flexible matrix to form a hierarchical porous composite. Therefore, in this work, we prepared MIL-100 (Fe) embedded in a cellulose matrix named MIL-100(Fe)/Cell, and used it as an adsorbent of methylene blue (MB) dye. According to the BET analysis, the specific surface area of the synthesized MOF is 294 m2/g which is related to the presence of the cellulose as efficient and green support. The structure of this composite is approximately hexagonal. Adsorption was studied as a function of contact time, adsorbent mass and pollutant load (concentration), and pH, and the effect of each of them on absorption efficiency was optimized. The MIL-100(Fe)/Cell was capable of removing 98.94% of MB dye with an initial concentration of 150 mg/L within 10 min at pH = 6.5 and room temperature. The obtained maximum adsorption capacity was 384.615 mg/g. The adsorption isotherm is consistent with the Langmuir models. The mechanism of MB adsorption proceeds through п-п and electrostatic interactions. [ABSTRACT FROM AUTHOR]

Global warming in 2023 shows no signs of slowing down. The situation alarms scientists, including the Intergovernmental Panel on Climate Change, the international body responsible for regularly developing knowledge on climate change. Indeed, some impacts are already threatening the environment. Today, the average global temperature has increased by about 1 °C compared to the pre-industrial era (1850–1900). At the current rate, the increase in global average temperature will reach 1.5 °C between 2030 and 2052. The greenhouse effect is unbalanced by human activities, in particular the use of fossil fuels (oil, gas, and coal), which lead to the release of greenhouse gases. CO2 represents nearly 2/3 of global greenhouse gas emissions caused by human activities and has the tendency to linger in the atmosphere for a long time. This is why the effect of other greenhouse gases is usually measured in CO2 equivalent. Current CO2 emissions will impact atmospheric concentrations and global temperatures for decades. To date, some solutions have been proposed to deal with this (energy transition, regulation of emissions, etc.). However, most of these solutions have not yet been sufficiently developed and/or do not offset the effects of ever-increasing industrialization on anthropogenic CO2 emissions. As a result, carbon capture and sequestration processes appear to be attractive solutions. CO2 capture can take place by absorption (chemical and/or physical) and/or adsorption (chemisorption and/or physisorption). Various compounds can act as sorbents, among which polysaccharides and lignin have special importance due to their many advantages, the most important of which are biodegradability, availability, relatively cheapness, environmental friendliness, etc. In this review, we report recent studies regarding polysaccharides and lignin-based materials for CO2 capture. Such materials can be in different forms such as composites, aerogels, hydrogels, pellets, heteroatom-doped materials, membranes, metal–organic frameworks (MOFs), porous carbons, etc. These materials are used for CO2 capture through the adsorption or absorption processes. [ABSTRACT FROM AUTHOR]

Chromium is a potentially poisonous and carcinogenic species, which originates from human activities and various industries such as leather, steel, iron, and electroplating industries. Chromium is present in various oxidation states, among which hexavalent chromium (Cr(VI)) is highly toxic as a natural contaminant. Therefore, chromium, particularly Cr(VI), must be eliminated from the environment, soil, and water to overcome significant problems due to its accumulation in the environment. There are different approaches such as adsorption, ion exchange, photocatalytic reduction, etc. for removing Cr(VI) from the environment. By converting Cr(VI) to Cr(III), its toxicity is reduced. Cr(III) is essential for the human diet, even in small amounts. Today, biopolymers such as alginate, cellulose, gum, pectin, starch, chitin, and chitosan have received much attention for the removal of environmental pollutants. Biopolymers, particularly polysaccharides, are very useful compounds due to their OH and NH 2 functional groups and some advantages such as biodegradability, biocompatibility, and accessibility. Therefore, they can be widely applied in catalytic applications and as efficient adsorbents for the removal of toxic compounds from the environment. This review briefly investigates the application of polysaccharide-based (nano)materials for efficient Cr(VI) removal from the environment using adsorption/reduction, photocatalytic, and chemical reduction mechanisms. [Display omitted] • Polysaccharide-based (nano)materials show remarkable potential for the removal of Cr(VI). • Recent studies on the preparation of polysaccharide-based (nano)materials have been reviewed. • Catalytic removal of Cr(VI) has been presented. • Future challenges for the removal of Cr(VI) using polysaccharide-based (nano)materials have been discussed. [ABSTRACT FROM AUTHOR]

Environmental pollution is one of the important concerns for human health. There are different types of pollutants and techniques to eliminate them from the environment. We hereby report an efficient method for the remediation of environmental contaminants through the catalytic reduction of the selected pollutants. A green method has been developed for the immobilization of copper nanoparticles on magnetic lignosulfonate (Cu NPs@Fe 3 O 4 -LS) using the aqueous extract of Filago arvensis L. as a non-toxic reducing and stabilizing agent. The characterization of the prepared Cu NPs@Fe 3 O 4 -LS was achieved by vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), high resolution TEM (HRTEM), X-ray diffraction (XRD), scanning TEM (STEM), thermogravimetry-differential thermal analysis (TG/DTA), fast Fourier transform (FFT), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron (XPS) analyses. The synthesized Cu NPs@Fe 3 O 4 -LS was applied as a magnetic and green catalyst in the reduction of congo red (CR), 4-nitrophenol (4-NP), and methylene blue (MB). The progress of the reduction reactions was monitored by UV–Vis spectroscopy. Finally, the biological properties of Cu NPs@Fe 3 O 4 -LS were investigated. The prepared catalyst demonstrated excellent catalytic efficiency in the reduction of CR, 4-NP, and MB in the presence of sodium borohydride (NaBH 4) as the reducing agent. The appropriate magnetism of Cu NPs@Fe 3 O 4 -LS made its recovery very simple. The advantages of this process include a simple reaction set-up, high and catalytic antibacterial/antioxidant activities, short reaction time, environmentally friendliness, high stability, and easy separation of the catalyst. In addition, the prepared Cu NPs@Fe 3 O 4 -LS could be reused for four cycles with no significant decline in performance. [Display omitted] • Facile synthesis of magnetic lignosulfonate supported copper nanoparticles. • Efficient reduction of MB, CR and 4-NP using Cu NPs@Fe 3 O 4 -LS catalyst. • Characterization of catalyst by FTIR, XRD, VSM, (HR)TEM, TG/DTA, EDS and XPS. • The catalyst can be reused at least four times with low loss of catalytic ability. • The antibacterial/antioxidant activities of Cu NPs@Fe 3 O 4 -LS were investigated. [ABSTRACT FROM AUTHOR]

The demand for lithium has increased incredibly during the last decade as it has become the mainstream for the growth of industrial products; especially batteries for electric vehicles and electronic devices. Given the high demand for lithium, researchers are focusing on methods for extracting lithium from a variety of sources. Among different liquid lithium extraction methods, lithium ion-sieve technology (LIS) is an emerging recovery method with great advantages over other approaches. LIS adsorption is a promising method for Li extraction owing to its low energy consumption, high lithium uptake capacity, environmentally friendly nature and superior lithium selectivity properties. A variety of physical and chemical methods can be applied to extract lithium from brines and ores. The present work critically reviews recent developments in lithium extraction and recovery using LIS adsorbents and membranes from aqueous solutions such as brine, seawater, etc. The paper has been particularly categorized based on the structure of the adsorbents and the pros and cons of various LIS adsorbents. Furthermore, this work emphasizes recent achievements with regard to the stability challenges encountered with LIS adsorbents. The favorable progress along with comparable advantageous such as higher lithium selectivity, lower environmental challenges, and higher energy efficiency have made LIS one of the most promising methods for lithium extraction from aqueous media. • This work provides an overview of lithium ion sieve technologies. • The focus of this work is on the materials that have been used to selectively recover Li. • Titanium and manganese based lithium ion sieves were comprehensively studied. • Challenges and future outlook of the membranes were also presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of novel polystyrene immobilized Brønsted acid ionic liquid catalyst (PS-Tet-SO 3 H). • The catalyst was characterized by FT-IR, XRD, XPS, TG/DSC, and SEM analyses. • The catalyst was used for the preparation of 5-hydroxymethylfurfural from fructose. • The catalyst can be reused four times without remarkable loss of catalytic activity. 5-Hydroxymethylfurfural (5-HMF) is one of the compounds, which has attracted a lot of attention due to its multi-functional nature and many applications in the industry. In this experimental study, 5-HMF has been synthesized using a polystyrene-supported Brønsted acid ionic liquid catalyst. This heterogonous catalyst has been synthesized via the decoration of 5-amino-1 H -tetrazole-bonded sulfonic acid onto the surface of chloromethylated polystyrene (PS-Tet-SO 3 H). The prepared PS-Tet-SO 3 H is was characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetry–differential scanning calorimetry (TG-DSC), and Scanning electron microscopy (SEM). PS-Tet-SO 3 H catalyst for has then been used in the synthesis of 5-HMF from fructose via an acid hydrolysis reaction. Finally, the prepared PS-Tet-SO 3 H can be recycled and reused for 4 cycles with no significant loss of performance. [ABSTRACT FROM AUTHOR]

• Synthesis of Fe 3 O 4 -chitosan@metformin-Cu(II) complex is prepared. • Synthesis of primary sulfonamides in water under ultrasonic irradiation. • N -Arylation of primary sulfonamides is performed in green media. • Easy magnetically separation of catalyst and good yields of products. • Catalyst can be reused five times without remarkable loss of catalytic activity. The application of chitosan, which has received much attention as a natural polymer and effective support, has many advantages such as biodegradability and biocompatibility. In this study, the immobilization of a copper complex on the magnetic chitosan bearing metformin ligand has been developed through immobilizing structurally defined metformin with long tail of (3-chloropropyl)trimethoxysilane (TMOS). The synthesized Fe 3 O 4 -chitosan@metformin-Cu(II) complex (Fe 3 O 4 -CS@Met-Cu(II)) was used as an effective, reusable and magnetic catalyst in the N -arylation of different derivatives of primary sulfonamides with arylboronic acids in ethanol. The primary sulfonamides were prepared from the reaction of sulfonyl chlorides with sodium cyanate in water under ultrasonic irradiation. Utilizing a wide variety of substrates in EtOH as a green solvent, high yields of the primary and secondary sulfonamides, easy work-up along with the excellent recovery and reusability of the catalyst, make this process a simple, economic and environmentally benign method. The synthesized Fe 3 O 4 -CS@Met-Cu(II) was characterized using various techniques such as XRD (X-ray diffraction), EDS (energy-dispersive X-ray spectroscopy), elemental mapping, TEM (transmission electron microscopy), FESEM (field emission scanning electron microscopy), VSM (vibrating sample magnetometer), ICP-MS (inductively coupled plasma mass spectroscopy), TGA (thermogravimetric analysis) and FT-IR (Fourier-transform infrared spectroscopy) analyses. The catalyst can be recycled and reused 5 times with no considerable loss of catalytic activity. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile synthesis of Pd NPs through laser ablation in liquid. • Synthesis of Pd NPs supported on the on kraft lignin/TiO 2 nanocomposite. • Structural verification of the nanocatalyst by XRD, FTIR, BET, SEM, EDX, and TEM analyses. • Catalytic performances of KL-T/Pd in the MB and MO reduction in water. • Nanocatalyst can be recovered and reused four times without any notable decreasing in its catalytic performance. The evaluation of dye degradation was adorned a great interest due to scarcity of water, courtesy of industrialization. Here, Kraft lignin was upgraded by immobilization of TiO 2 nanoparticles (NPs) by the reflux method (KL-T). Palladium (Pd) NPs were produced in a promising way by laser ablation in liquid (LAL) and loaded on KL-T to prepare an efficient nanocatalyst (KL-T/Pd). The synthesized KL-T/Pd is characterized by X-ray diffraction (XRD), Fourier transforms infrared (FT-IR), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectrometry (EDX), and Transmission electron microscope (TEM) analyses. The KL-T/Pd nanocomposite was applied as an efficient and novel nanocatalyst for the reduction of methylene blue (MB) and methyl orange (MO) by NaBH 4 as a reducing agent in aqueous media at ambient temperature. Our experimental results displayed that the 1 mg of KL-T/Pd catalyst can be reduced MB and MO organic dyes within 23 and 8 s, respectively at room temperature. The KL-T/Pd nanocatalyst can be recycled and reused four times with no considerable loss of performance. Having different advantages such as high catalytic performance, safe synthesis method, and high stability, lignin was suggested as a natural substrate. [ABSTRACT FROM AUTHOR]

• Recent advances in tetrazole-based catalysts are described. • Environmental and catalytic applications of tetrazole-based (nano)materials have been presented. • Stability and catalytic properties of tetrazole-based (nano)materials are highlighted. • Future challenges on tetrazole-based (nano)materials are discussed. Increasing interest in tetrazoles and tetrazole based materials in the recent century has been followed by enormous research efforts devoted for the synthesis of various kinds of materials based on these five membered heterocyclic compounds, which basically contain four nitrogen atoms. The structure of tetrazoles and their derivatives are crucial in preparing complexes since they can act as ligands to modify the reactivity and selectivity of the metal centers in the catalyst and prepare energetic materials. The wide field of tetrazole applications as efficient, air stable and inexpensive materials has drawn attention to the methods to synthesize various kinds of tetrazoles and their derivatives. This study primarily focuses on the fabrication methods of tetrazoles and preparation of tetrazole based compounds and their utilizations in environmental, catalytic, and energetic applications. The significant applications of tetrazole, as a catalyst, energetic material and efficient ligand in the organic catalysis or formation of various catalysts are described with an emphasis on its performance, reusability and stability and environmental concerns such as treatment of wastewater and water. Finally, a brief summary and an outlook on some of the scientific challenges and opportunities of these materials have also been discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Heck cross-coupling reaction (HCR) is one of the few transition metal catalyzed C C bond-forming reactions, which has been considered as the most effective, direct, and atom economical synthetic method using various catalytic systems. Heck reaction is widely employed in numerous syntheses including preparation of pharmaceutical and biologically active compounds, agrochemicals, natural products, fine chemicals, etc. Commonly, Pd-based catalysts have been used in HCR. In recent decades, the application of biopolymers as natural and effective supports has received attention due to their being cost effective, abundance, and non-toxicity. In fact, recent studies demonstrated that biopolymer-based catalysts had high sorption capacities, chelating activities, versatility, and stability, which make them potentially applicable as green materials (supports) in HCR. These catalytic systems present high stability and recyclability after several cycles of reaction. This review aims at providing an overview of the current progresses made towards the application of various polysaccharide and gelatin-supported metal catalysts in HCR in recent years. Natural polymers such as starch, gum, pectin, chitin, chitosan, cellulose, alginate and gelatin have been used as natural supports for metal-based catalysts in HCR. Diverse aspects of the reactions, different methods of preparation and application of polysaccharide and gelatin-based catalysts and their reusability have been reviewed. Current trends, challenges and future prospects exploiting the sustainable applications of chitin, chitosan, starch, cellulose, pectin, alginate, gelatin and gum based (nano)catalysts for the Heck coupling reactions, are highlighted. [Display omitted] • Advances in Heck coupling reactions by biopolymer-based catalysts are described. • Synthetic methods for attaining biopolymer-based catalysts are highlighted. • Catalytic activity of chitin, chitosan, starch, cellulose, pectin, alginate, gelatin and gum based catalysts are presented. • Mechanistic details are provided for Heck coupling reactions using biopolymer-based catalysts. • Future challenges pertaining to Heck coupling reactions using biopolymer-based catalysts are discussed. [ABSTRACT FROM AUTHOR]

The nutrient resources make up a significant portion of wastes from all around the world. According to several recent studies, nuts and their residues are regarded as valuable natural resources for a nutrition and the other applications. The presence of waste nut residues in nature may lead to the environmental problems. The use of this waste for various applications is a very important issue. Nuts contain precious chemicals, which may be advantageous for preparing (nano)materials for the catalytic purposes. Different parts of nuts such as shell, kernel, extracts, etc. have valuable components, which can be used directly to make a variety of heterogeneous catalysts or as stabilising and reducing agents for nanoparticles. For example, the shell of some nuts is rich in lignin, cellulose and hemicellulose, which can be used as an effective and environmentally friendly supports for the heterogeneous catalysts. The design and application of safer and cheaper catalytic systems for different applications including organic synthesis, hydrogen evolution reactions, oxidation reactions, hydrolysis, degradation of pollutants, etc., are an extreme necessity in which nuts and their wastes can play a significant part due to their excellent chemical properties. Cheaper catalysts comprise of natural compounds such as biopolymers, aluminosilicates, kernel shells, zeolites, diatomites, agricultural wastes (such as bagasse pith, rice husk, smaise cob, coconut shell), nut wastes, etc. These compounds are of natural origin and therefore do not harm the environment. Since they are considered a type of waste, they are also cheap and economical. This review for the first time summarises the preparation of (nano)materials from nuts as an environmentally benign resources and their catalytic applications and highlights the industrial benefits and potential applications of these economically sustainable green resources to convert waste to wealth. The recent developments in the synthesis and applications of bio(nano)catalysts in catalytic and environmental areas have been discussed. In this review, the application of nuts as an efficient supports and green reducing agents for the synthesis of nanomaterials has been discussed. Due to the beneficial compounds, which they contain, activated carbon can be extracted from them and used to make heterogeneous catalysts. These bio(nano)catalysts are applied for organic synthesis, hydrogen evaluation reaction (HER), oxidation reactions and hydrolysis for an environmental applications in reduction and degradation of nitro compounds and organic dyes. [Display omitted] • Design and application of safer and cheaper catalytic systems for different applications. • Recent studies on the preparation of nut-derived bio(nano)materials have been reviewed. • Catalytic activities of nut-derived bio(nano)catalysts have been presented. • Application of nut-derived materials for removal of environmental contaminants. • Future challenges on the synthesis of nut-derived bio(nano)materials have been discussed. [ABSTRACT FROM AUTHOR]

• Novel chitosan supported 1-phenyl-1 H -tetrazole-5-thiol ionic liquid copper(II) complex was prepared. • The catalyst was characterized by XRD, EDS, elemental mapping, STEM, FT-IR, TG/DTA, ICP-MS and TEM analyses. • The catalyst was used in the synthesis of arylaminotetrazoles. • The catalyst can be reused five times without remarkable loss of catalytic activity. A recyclable functional hybrid catalyst was prepared via a simple method using chitosan as a linear polysaccharide and an ionic liquid. In this work, the synthesis of chitosan supported 1-phenyl-1 H -tetrazole-5-thiol ionic liquid copper(II) complex (CS@Tet-IL-Cu(II)) was investigated. The synthesized CS@Tet-IL-Cu(II) was characterized using XRD, EDS, elemental mapping, STEM, FT-IR, TG/DTA, ICP-MS and TEM analyses. CS@Tet-IL-Cu(II) was applied as an effective and novel catalyst in the synthesis of arylaminotetrazoles via the cycloaddition reaction of arylcyanamides and NaN 3 in DMF solvent. The experimental results indicated that the type of substituents on arylcyanamides could affect the type of products (A or B isomer). The arylcyanamides with electron withdrawing and donating groups can produce isomer A (5-arylamino-1 H -tetrazole) and isomer B (1-aryl-5-amino-1 H -tetrazole), respectively. In addition, CS@Tet-IL-Cu(II) can be reused five times with no noteworthy loss of performance. [ABSTRACT FROM AUTHOR]

Over the course of a few decades, the concern of environmental damages of fossil fuels, an increase in CO 2 emission and a decrease of hydrogen have been growing more and more. Accordingly, hydrogen production is a crucial issue nowadays. Different polymers are applied to attain the purpose. Among all polymers, biodegradables polymers are the best choices to develop the main aim. Polysaccharides and proteins are biodegradable polymers with unique places and advantages with regards to their ecofriendly properties. There are different techniques to apply and achieve the foremost purpose. It is worthwhile to mention that green and facile methods are always attracting attention in different aspects and fields. The three non-polluting and economical techniques, that is, electrochemical hydrogen evolution reaction (HER), photocatalytic technique, and hydrolysis of hydrides, are reviewed in this paper. This review helps researchers, who are environment supporters, to evaluate and choose the most ecological biopolymers and processes in their work. [Display omitted] • Developments in hydrogen evolution by biopolymer-derived (nano)catalysts have been described. • Summary of synthetic procedures to obtain biopolymer-derived (nano)catalysts. • Future challenges of hydrogen evolution using biopolymer-derived (nano)catalysts have been discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Advances in catalytic and environmental applications of biopolymer-based ionic liquids are described. • Synthetic methods are highlighted for obtaining polysaccharide and lignin-based ionic liquids. • Catalytic activity of alginate, cellulose, lignin, chitosan and starch based ionic liquids have been reviewed. Today, the use of heterogeneous catalysts for various chemical and environmental transformations is of great interest. For this aim, researchers have applied different natural or synthetic supports for the heterogeneity of catalysts. The most widely used catalyst supports are perlite, bentonite, diatomite, and synthetic and natural polymers. Natural polymers (biopolymers) are one of the most promising compounds, which are widely applied as efficient and green supports. Among biopolymers, polysaccharides are highly regarded as catalyst supports by researchers. Many studies have been performed on improvements in the synthesis, characterization, and applications of biopolymers such as alginate, cellulose, lignin, chitin/chitosan and starch based catalysts. These polymers have some advantages such as biodegradability, biocompatibility, non-toxicity, and unique structures. This review paper describes the applications of alginate, cellulose, chitosan, starch and lignin supported ionic liquids (ILs) as catalysts for many catalytic and environmental applications. These catalysts are applied in reactions such as acetalization, hydrogenation, condensation, reduction, oxidation, epoxidation, and synthesis of 1,2,3-triazoles, dichlorophenylphosphine, diaryl ether, etc. As green resources, polysaccharides and lignin-based catalysts have many merits such as low cost, availability, good stability, recyclability, etc. [ABSTRACT FROM AUTHOR]