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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]

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]

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]

[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]