Loess clay (LC), a very abundant clay with granules and high hydrophilicity, was modified by surface grafting copolymerization of functional monomers, such as acrylamide (AM) and sodium p-styrene sulfonate (StS), and a cross-linking agent (N,N-methylenebisacrylamide: MBA), which afforded a LC surface grafting copolymer (LC-PAmS). Its structure and composition were characterized by Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM). Acting as a novel and low-cost Loess-based polymer adsorbent, its adsorption behaviors were investigated with removing basic fuchsin (BF) in aqueous solution. After optimizing conditions, the removal rate got to 98.4% in 40 min at room temperature. Its adsorption mechanism was also investigated. It was found that the adsorption isotherm model could meet the Freundlich isotherm requirements and the dynamics were consistent with a pseudo-second-order kinetic model. In summary, LC-PAmS is a kind of polymer adsorbent for practically applied in wastewater treatment.

•The sources of discarded biomass and traditional treatment are summarized.•The main composition and polymer chains of discarded biomass material are described.•The novel approaches for reutilization of discarded biomass are discussed.•Functional polymer materials prepared by using discarded biomass are summarized.Biomass is abundant and recyclable on the earth, which has been assigned numerous roles to human beings. However, over the past decades, accompanying with the rapid expansion of man-made materials, such as alloy, plastic, synthetic rubber and fiber, a great number of natural materials had been neglected and abandoned, such as straw, which cause a waste of resource and environmental pollution. In this review, based on introducing sources of discarded biomass, the main composition and polymer chains in discarded biomass materials, the traditional treatment and novel approach for reutilization of discarded biomass were summarized. The discarded biomass mainly come from plant wastes generated in the process of agriculture and forestry production and manufacturing processes, animal wastes generated in the process of animal husbandry and fishery production as well as the residual wastes produced in the process of food processing and rural living garbage. Compared with the traditional treatment including burning, landfill, feeding and fertilizer, the novel approach for reutilization of discarded biomass principally allotted to energy, ecology and polymer materials. The prepared functional materials covered in composite materials, biopolymer based adsorbent and flocculant, carrier materials, energy materials, smart polymer materials for medical and other intelligent polymer materials, which can effectively serve the environmental management and human life, such as wastewater treatment, catalyst, new energy, tissue engineering, drug controlled release, and coating. To sum up, the renewable and biodegradable discarded biomass resources play a vital role in the sustainable development of human society, as well as will be put more emphases in the future.Based on discussing the main composition and polymer chains in discarded biomass, their reutilization approaches, from the perspective of polymer, especially to prepare functional polymer materials were summarized.Download high-res image (71KB)Download full-size image

Superoxide anion radical (O\(_{2}^{\bullet -}\)) is a noxious reactive oxygen species (ROS). Transition metal ion complexes have been generally used as antioxidants to eliminate ROS. In this work, a neoteric water-soluble biopolymer metal complex (BSA-M) was prepared by conjugating the soluble biopolymer bovine serum albumin (BSA) with three transition metal ions (M, M =Cu, Co, Mn). The binding mode and ratio of metal ions bound to albumin were investigated. The BSA-M complexes were characterized by UV-Vis, circular dichroism (CD) spectra and polyacrylamide gel electrophoresis (PAGE). BSA served as polymer scaffold and the metal complex functioned as the catalytic active center. The results demonstrated that the structure of BSA remained unchanged when the binding ratio of transition metal ion complex to BSA was 5:1. Furthermore, the scavenging superoxide anion free radical (O\(_{2}^{\bullet -}\)) activity of biopolymer-metal complexes were determined by nitroblue tetrazolium light reduction assay method. The antioxidant capacity of BSA-M has markedly increased. The conjugated BSA-M (M=Cu, Mn) showed preeminent scavenging activity for O\(_{2}^{\bullet -}\), and the EC50 value of the BSA-Cu was 0.038 ±0.0013 μmol⋅L−1, which is comparable to EC50 value (0.041±0.001 μmol⋅L−1) of the natural superoxide dismutase (SOD), the analog quantity reached 107%. As a consequence, it can be considered as a bio-functional mimic of enzyme SOD and has a promising application prospect in antioxidant drug field.