Cross-Linked Chitosan-Based Hydrogels for Dye Removal

Abstract

Synthetic dyes are a major class of recalcitrant organic compounds, often occurring in the environment as a result of their wide industrial use. More than 100,000 dyes are commercially available. Synthetic dyes are common contaminants, many of them being toxic or carcinogenic. Colored effluents from industrial plant are also perceived by the public as an indication of the presence of a dangerous pollution. Even at very low concentrations, dyes are both highly visible, inducing an esthetic pollution, and impacting the aquatic life and food chain, as a chemical pollution. Dye contamination of water is a major problem worldwide and the treatment of wastewaters before their discharge into the environment is a priority. Dyes are difficult to treat due to their complex aromatic structure and synthetic origin. In general, a combination of different physical, chemical and biological processes is often used to obtain the desired water quality. However, there is a need to develop new removal strategies and decolorization methods that are more effective, acceptable in industrial use, and ecofriendly. Currently, there is an increasing interest

Dye removal by biosorption using cross-linked chitosan-based hydrogels

“…Recently reported biosorption capacities are also noted to give some idea of biosorbent effectiveness. This article is an abridged version of the chapter published by Crini et al (2019) in the series Sustainable Agriculture Reviews.…”

Chitosan for direct bioflocculation of wastewater

“…Similar to classical flocculation, bioflocculation by chitosan involves combining insoluble particles and dissolved organic matter into larger aggregates, which can be then removed in subsequent sedimentation and filtration stages (Morin- Crini et al 2019;Vidal and Moares 2019). Chitosan chains first destabilize suspended and colloidal particles in wastewater by forming micro-flocs in the coagulation step.…”

“…This is followed by the addi-tion of coagulant aids or flocculants (step 3) to enhance the treatment efficiency and sedimentation rate by mechanical aggregation of micro-flocs into visible, dense and rapid settling flocs. The filter press (last step 5) is an equipment allowing to filtrate sludge under pressure in order to separate the liquid (filtrate) and the solid phase (the cake) it is non-toxic, biocompatible, biodegradable and classified as a green product (Morin- Crini et al 2019). The cationic biopolymer chitosan has also drawn particular attention as a flocculating agent for application in water industries due to its eco-friendly character, low cost and outstanding performances.…”

“…Crini thus spoke of two-in-one materials (Crini and Badot 2007;Crini et al 2009a, b). Several recent reviews have demonstrated that direct bioflocculation is an effective and competitive approach, and that chitosan is a promising bioflocculant for environmental and purification purposes (Chong 2012;Lee et al 2014;Crini 2015;Bhalkaran and Wilson 2016;Laamanen et al 2016;Yang et al 2016;Kanmani et al 2017;Ummalyma et al 2017;Wang and Zhuang 2017;Desbrières and Guibal 2018;Pakdel and Peighambardoust 2018;Song et al 2018;Salehizadeh et al 2018, Van Tran et al 2018Crini et al 2019;Vidal and Moares 2019).…”

Applications of chitosan in food, pharmaceuticals, medicine, cosmetics, agriculture, textiles, pulp and paper, biotechnology, and environmental chemistry

“…Because of its remarkable macromolecular structure, physical and chemical properties, bioactivities, and versatility, quite different from those of synthetic polymers, the biopolymer chitosan has received much attention in fundamental science, applied research, and industrial biotechnology (Crini 2019;Crini et al 2009Crini et al , 2019Kim 2011Kim , 2014 1 3 Castro and Paulín 2012;Teng 2012;Sashiwa and Harding 2015;Dima et al 2017;Philibert et al 2017). Currently, chitosan and its derivatives have practical applications in the form of solutions, suspensions, particles, e.g., beads, resins, spheres, nanoparticles and sponges, gels/hydrogels, foams, membranes and films, fibers, microscopic threads, and scaffolds in many fields: medicine and biomedicine, pharmacy, cosmetology, hygiene and personal care, food industry and nutrition, agriculture and agrochemistry, textile and paper industries, edible film industry and packaging, biotechnology, chemistry, and catalysis, chromatography, beverage industry and enology, photography, and other emerging fields such as nutraceuticals, functional textiles and cosmetotextiles, cosmeceuticals, nanotechnology, and aquaculture (Sandford 1989;Onsoyen and Skaugrud 1990;No and Meyers 1995;Li et al 1997;Ravi Kumar 2000;Khor 2001;Struszczyk 2002;Honarkar and Barikani 2009;Crini et al 2009;Davis 2011;Ferguson and O'Neill 2011;Kardas et al 2012;Sarmento and das Neves 2012;Yao et al 2012;Khor and Wan 2014;Bautista-Baños et al 2016;Dutta 2016;Hamed et al 2016;Ahmed and Ikram 2017;Amber Jennings and Bumgardner 2017a, b;Arfin...…”