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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]

• Green synthesis of Cu/Fe 3 O 4 nanoparticles using Alhagi camelorum aqueous extract. • synthesis of 2-imino-3-aryl-2,3-dihydrobenzo[ d ]oxazol-5-ol derivatives at room temperature. • Characterization of the catalyst using TEM, FT-IR, XRD, FESEM, EDS, and UV–Vis. • Catalyst can be recovered and reused five times by magnetic separation with no significant reduction of catalytic activity. A novel, low-cost and green method was developed for the synthesis of Cu/Fe 3 O 4 nanoparticles (NPs) using Alhagi camelorum aqueous extract as a safe reducing agent and effective stabilizer without addition of any chemical reducing agents or surfactants. TEM (transmission electron microscopy), FT-IR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), FESEM (field emission scanning electron microscopy), EDS (energy-dispersive X-ray spectroscopy), and UV–Vis (ultraviolet visible) analyses were used for the characterization of green synthesized NPs. The FT-IR analysis confirmed the existence of different functional groups of Alhagi camelorum extract phytochemicals which were responsible for the fabrication of NPs. Finally, the magnetic Cu nanocatalyst was employed for the preparation of 2-imino-3-aryl-2,3-dihydrobenzo[ d ]oxazol-5-ol derivatives via the reaction of arylcyanamides and p -benzoquinone at ambient temperature. The biosynthesized Cu/Fe 3 O 4 NPs can be recovered and reused for five cycles with no significant reduction of catalytic activity. In this work, Cu/Fe 3 O 4 nanoparticles have been fabricated using Alhagi camelorum aqueous extract. The catalyst synthesized shows the best activity in the synthesis of 2-imino-3-aryl-2,3-dihydrobenzo[ d ]oxazol-5-ol derivatives in high yields within 15–90 min. Image, graphical abstract [ABSTRACT FROM AUTHOR]

[Display omitted] • Advances in oxidation reactions by polymer supported cobalt complexes/nanoparticles, are described. • Summary of synthetic methods for attaining polymer supported cobalt complexes/nanoparticles. • Catalytic oxidation of mercaptans, alcohols, alkenes etc , are presented. • Mechanistic details are provided for oxidation with polymer supported cobalt complexes/nanoparticles. • Future challenges on oxidation reactions using polymer supported cobalt complexes/nanoparticles are discussed. Polymers play an important role in the fabrication of heterogeneous (nano)catalysts applied for many chemical syntheses and conversions. The excellent properties of polymers, for instance, high thermal stability, large surface area, simplicity of modification and high mechanical strength make them ideal catalyst supports. To reduce the toxicity of metal nanoparticles (MNPs) or complexes, a new method has been developed in recent years for the fabrication of supported MNPs. Synthesis of MNPs or metallic complexes on polymer support has been applied as a prospective solution to avoid the accumulation of waste MNPs in the medium via a recovery process. The blending of nanoparticles with polymers forms nanocomposites with unique properties due to their specific shape, size, and nature. This review is an overview of the current developments in manufacturing, characterization, and applications of cobalt (Co) complexes/NPs decorated on the surface of various polymers for the catalytic oxidation of mercaptans, alcohols, alkenes, etc. using various oxidizing agents such as H 2 O 2 , O 2 , TBHP (tert -butyl hydroperoxide), etc. Eventually, we envision the current/future challenges and opportunities for these polymer-supported cobalt (nano)catalysts in the field of chemical transformations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Recent advances in graphene-based (nano)materials have been described. • Reduction of hazardous nitro compounds by graphene-based (nano)materials have been reviewed. • Characterization of graphene-based (nano)materials have been highlighted. • Future challenges on the reduction of hazardous nitro compounds are discussed. The rapid progresses in the reduction of nitro compounds represent a potent and extensively utilized transformation, which allows the introduction of amino compounds. From the standpoint of organic chemistry, amines have many applications in the synthesis of drugs, biologically active molecules, pharmaceutical products, dyes, polymers, etc. For this aim and owing to the environmental concerns about toxic nitro contaminants such as 4-nitrophenol (4-NP), up to know, much research has been carried out on the reduction/degradation of nitroarenes for the fabrication of amines using different heterogeneous (nano)catalysts. This review provides the current developments in the area of production, classification and applications of graphene-based catalysts in the reduction of nitro compounds to amines. The application of graphene derivatives in the synthesis of various catalysts is advantageous compared to other catalysts and thus increases the rate of reduction of nitro compounds. The use of these catalysts offers several benefits such as straightforward work-up, high catalytic prowess and recovery. [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]

Gold nanoparticles (Au NPs) were fabricated by laser ablation in liquid (LAL) as a green method and decorated on graphitic carbon nitride (g-C 3 N 4) by a facile ultrasonication method. g-C 3 N 4 was prepared via urea pyrolysis. The prepared g-C 3 N 4 /Au (denoted as CN/Au) nanocomposite was characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectrometry (EDS). The synthesized CN/Au nanocomposite was applied as an efficient catalyst in the reduction of 4-nitrophenol (4-NP) and methyl orange (MO) using NaBH 4 at room temperature. The recyclability of CN/Au catalyst was examined. Image 1 [ABSTRACT FROM AUTHOR]

One of the most abundant wastes from all around the world is nutrient resources. Among them, fruits, their extracts, and residues comprise a major portion, which contain many valuable components that get lost during disposal or become burden on the shrinking landfills. These concerns are addressed by seeking sustainable processing methods that would have a minimal environmental impact. The crops contain renewable chemicals which are useful for catalysis, wastewater treatment, or preparation of nanomaterials; there has been an upsurge for the industrial applications of (nano)materials as their environmental and catalytic appliances is a fascinating subject to design cheaper and safer catalytic systems. Due to the excellent chemical properties of the fruit extracts, they have garnered attention as cost‐effective catalysts and support materials. This review focuses on the preparation of (nano)materials and their catalytic and environmental applications and highlights the potential appliances and industrial benefits derived from these low‐cost renewable and sustainable greener sources thus essentially converting waste into wealth. [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]

Organic materials produced from diverse industries such as paint, leather, textile, etc., produce various challenging pollutants in the environment. Today, the development of effective methods to remove pollutants is a vital and fundamental issue. One of the effective ways to remove these pollutants from the environment is to use heterogeneous catalysts. In recent decades, polymer-based metal catalysts have received much attention as effective and heterogeneous catalysts. Among various metals, silver (Ag) has unique properties and is appropriate for environmental remediation. This review summarized the recent progress in synthesizing polymer-supported Ag complexes/nanoparticles and their applications for environmental remediation. Application of polymer-supported Ag complexes/nanoparticles suggested some advantages like high catalytic ability, reusability, direct preparation, and simple work-up. [Display omitted] • Polymer-supported silver complexes/nanoparticles show remarkable potential for remediation of pollutants. • Recent studies on the preparation of polymer-supported silver complexes/nanoparticles are introduced. • Catalytic remediation of environmental pollutants, are presented. • Future challenges for remediation of pollutants using polymer-supported (nano)materials are discussed. [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]

The application of (bio)wastes as alternatives to expensive existing catalysts is an approach that can be used to reduce environmental pollution problems. Animal bone wastes have attracted much attention as environmentally friendly heterogeneous catalysts for chemical transformations such as transesterification, oxidation, and biofuel production, owing to the substantial availability of valuable hydroxyapatite (HAp) in their structure. Most catalysts based on bone can be prepared easily by calcination. High‐temperature calcination yields highly active catalysts. Heterogeneous catalysts prepared from these renewable sources could also simply be reused and recovered without any important loss of catalytic performance. This paper reviews past efforts and recent progress on the development of different eco‐friendly catalysts derived from bone waste and some of their catalyzed chemical transformations. However, future challenges focus on crediting the conversion of unusable wastes to valuable sources to meet global requirements © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

• Advances in oxidation reactions by polysaccharide derived (nano)catalysts, are described. • Summary of synthetic methods for attaining polysaccharide derived (nano)catalysts. • Catalytic oxidation of alcohols, phenols, etc , are presented. • Future challenges on oxidation reactions using polysaccharide derived (nano)catalysts are discussed. Exploitation of polymers as effective starting materials to produce various valuable catalysts is attracting the attention of industrial and academic researchers. Moreover, among all polymers, natural polysaccharides such as cellulose, starch, alginate, gum, pectin, chitin and chitosan have drawn the most attention in recent years due to their unique structural features and important potential applications. A lot of studies have been performed on the synthesis of polysaccharide based (nano)catalysts and their application in chemical transformations. The present review provides recent developments on polysaccharides as green resources for the production of (nano)catalysts. Herein, the application of polysaccharide based (nano)catalysts derived from different organisms, plants or animals in oxidative transformations has been reviewed. These compounds can be used as economical and recyclable catalytic materials for various oxidation reactions including oxidation of alcohols, phenols, sulfides etc. The challenges in the application of polysaccharide based (nano)catalysts have also been discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Advances in oxidation reactions by lignin derived (nano)catalysts, are described. • Summary of synthetic methods for attaining lignin derived (nano)catalysts. • Catalytic oxidation of alcohols, phenols, etc, are presented. • Mechanistic details are provided for oxidation with lignin derived (nano)catalysts. • Future challenges on oxidation reactions using lignin derived (nano)catalysts are discussed. Recently, the attention to bio-based catalysts has been on rise. The present review explains the developments regarding preparation, characterization and utilization of lignin based (nano)catalysts in oxidation reactions. Herein, the application of lignin in the preparation of (nano)catalysts and their catalytic prowess in oxidative transformations will be overviewed. Lignin offers exceptional physicochemical characteristics and important potential applications. Lignin can be used as a precursor or template to prepare novel eco-friendly catalysts. This review paper proposes the rational design of active, economical, recyclable and efficient catalysts for different oxidation reactions including oxidation of alcohols, phenols, etc. [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]

Environmental remediation means removing hazardous pollutants and toxic contaminants from various environmental media. Development of effective, sustainable, low cost heterogeneous catalysts for the treatment of organic/inorganic contaminants is highly desirable and is still a main challenge. Today, the development and use of new and low-cost routes for catalytic reduction, degradation, adsorptive removal, and decomposition of pollutants from wastewater and the environment have become an urgent global issue. In recent years, polymer supported copper nanoparticles (Cu NPs)/complexes have been used as suitable catalysts for the degradation, decomposition, and reduction reactions due to their properties such as high surface area, thermal stability, and mechanical strength. This review summarizes the literature reports from 2008 and recent advances in the polymer supported Cu NPs/complexes for the environmental remediation processes such as (photo)degradation of wastewater contaminants and organic dyes, reduction of toxic nitro contaminants such as 4-nitrophenol (4-NP) and 2-nitrophenol (2-NP), decomposition of H 2 O 2 , dehalogenation of aromatic chloride, and CO oxidation. Polymers are more favorable in the fabrication of heterogeneous catalysts compared to conventional catalysts due to their capability of increasing degradation, decomposition or reduction rate of organic and inorganic pollutants. The use of polymer supported Cu NPs/complexes offers several merits such as straightforward preparation, easy work-up, high catalytic performance, and reusability. [Display omitted] • Dyes, organic and inorganic pollutants considerably affect the environment, human and aquatic life. • The properties, structure, and preparation methods of polymer supported copper catalysts are discussed. • The development of pollutant degradation using polymer supported copper catalysts is summarized. • Future challenges on the synthesis of polymer supported copper catalysts are discussed. [ABSTRACT FROM AUTHOR]

• An overview of synthesis methods of polymer-supported ruthenium nanoparticles/complexes is given. • Oxidation reactions using polymer-supported ruthenium nanoparticles/complexes are reviewed. • Catalytic oxidation of alcohols, D-glucose, 5-hydroxymethylfurfural etc., are presented. • The future prospects of polymer-supported ruthenium catalysts in oxidation reactions are discussed. Polymers are extensively used as supports for the fabrication of catalysts. They have many advantages such as high thermal stability, ease of modification, high mechanical strength and large surface area. In recent years, the methods for the preparation of metal nanoparticles and complex based catalysts have been developed to a great extent. The presence of supports in the construction of catalysts prevents the accumulation of metal nanoparticles. In this review, polymer-supported ruthenium (Ru) catalysts (in two complex and nano forms) have been covered as significant catalysts for the oxidation of compounds such as types of alcohols, D-glucose, 5-hydroxymethylfurfural, etc. Oxidation of alcohols is of outstanding importance both in industrial and academic research. The solvent, oxygen pressure and temperature are the significant reaction parameters in the process. The advantages and differences related to the reported polymer-supported Ru catalyst systems have been reviewed, while new progresses, for example, a catalyst system for optimal oxidations, have also been outlined. Image, graphical abstract [ABSTRACT FROM AUTHOR]

[Display omitted] • Advances in hydrogenation by polymer-supported palladium complexes, are described. • Synthetic methods are highlighted for attaining polymer-supported palladium complexes. • Catalytic hydrogenation of carbonyl- and nitro-compounds, alkynes, and alkenes, are presented. • Mechanistic details are provided for hydrogenation with polymer-supported Pd catalysts. • Future challenges pertaining to hydrogenation reactions using Pd catalysts, are discussed. Hydrogenation reactions are useful pathways and comprise an integral operation to generate valuable organic compounds. Hydrogenation reactions not only provide an effective route for the preparation of organic compounds such as amines, alkenes, alkanes, alcohols, etc. but also a significant technique to degrade environmental pollutants; reactions are often catalyzed by palladium (Pd) complexes supported on the surface of the polymers, viz. organic or non-organic and are widely deployed owing to their high efficiency, recyclability and good selectivity. Herein, an overview is presented on current developments for the generation of different classes of polymer supported palladium complexes, their characterization and application in hydrogenation of assorted compounds comprising double bonds such as carbonyl- and nitro-compounds, alkynes, and alkenes. The literature from 1981 onwards is summarized pertaining to the hydrogenation reactions deploying polymer-supported Pd complexes catalysts under diverse conditions with special emphasis on the distinguished role of polymers as support in the structural and morphological features of the ensuing catalysts. [ABSTRACT FROM AUTHOR]