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Super adsorbents exhibit great potential to remove pollutants from media or store considerable amounts of water, which may undermine the pressure triggered by environmental pollution and shortage of water resources. Super adsorbents made from biopolymers have been an attractive topic because of biodegradability, renewability and outstanding adsorption capacity. Hemicelluloses are a type of biopolymers very abundant in agricultural, forestry and pulping industrial wastes. Hemicellulose-based bio-adsorbents are thriving because the inherent chemical structures and physical properties of hemicelluloses make themselves easy to be processed into matrix materials applicable in super adsorbents. This review summarizes recent studies in hemicellulose-based bio-adsorbents, i.e. hydrogels and activated carbons, from the perspectives of types, applications, fabrication methods, the elements affecting the adsorption performance and the kinetics of adsorption process, which thus helps to further improve the properties of hemicellulose-based bio-adsorbents and to promote the industrial production and utilization of hemicelluloses and hemicellulose-based bio-adsorbents., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Bio-based additives received significant attention in pulp and paper properties improvement. For this, the most cited biochemical Cellulose Nano Fibrils (CNFs) and Cationic Starch (CS) were experimentally compared with the most declared synthetic chemical, Cationic Polyacrylamide (CPAM). SEM images showed better paper surface filling by the utilization of the chemicals. The three studied polymers, in solely or combination mechanism, improved mainly bagasse pulp and paper properties compared to the blank sample, except for pulp drainage, which decreased by CNFs to lower volumes presumably due to its intrinsic characteristics. Cationic polymers (CP) compared to CP/CNFs approaches increased pulp retention and drainage but decreased paper density and strengths. The best pulp retention and drainage achieved by CS followed by CPAM, while paper air persistency, density, and strength properties evaluated highest by CP/CNFs followed by CNFs. Generally, CS revealed a more significant improvement in pulp and paper properties than CPAM either with or without CNFs., (Copyright © 2021 Elsevier B.V. All rights reserved.)

3D printing enables the complex or customized structures production in high speed and resolution. However, the lack of bio-based materials with user-defined biochemical and mechanical property is a significant barrier that limits the widespread adoption of 3D printing for products fabrication. Development of eco-friendly natural-derived biopolymers for 3D printing technologies and their promising application in different areas are of huge academic, and environmental interests. This paper reviews the state-of-the-art in terms of 3D printing technology using natural-derived feedstocks, including lignocellulose, starch, algae, and chitosan-based biopolymers. Special consideration is given to the development of lignocellulosic materials, i.e. cellulose, hemicellulose, lignin, and their derivatives as 3D printing feedstocks. A strategical development roadmap with identified material property requirements, key challenges, as well as possible solutions was proposed. It serves as guideline aiming to explore natural-derived biopolymers as novel feedstocks for different 3D printing technologies that will be potentially applied in various areas., (Copyright © 2018 Elsevier Ltd. All rights reserved.)