Chitosan for wastewater treatment

Abstract

Chitosan (an amino-polysaccharide obtained from deacetylation of chitin, the major constituent of crustaceous shells and insect cuticles) presents a cationic character in acidic media allowing its dissolution, its shaping and possible ion-exchange interactions with anionic compounds (a property applied in adsorption and coagulation-flocculation processes). In neutral media, non-protonated amino groups allow complexation of metal cations or organic chemicals. These different properties explain the interest taken by the scientific community in using this biopolymer. In solution it contributes to complex metals and their recovery by complexation-assisted ultrafiltration. It can also be used to coagulate-flocculate organic compounds (as anionic dyes). In the solid state, it can be used for metal ion adsorption, as well as adsorption of organic compounds (dyes, pesticides, drugs, endocrine disruptors, etc.). The adsorption and coagulation-flocculation processes will be compared and examples considered. Moreover, it is noteworthy that the thermal degradation of this type of material is also more environmentally friendly than that of conventional synthetic resins (production of hazardous by-products, etc.), a supplementary advantage of these biopolymer-based sorbents. Combined with its ability to be chemically or physically modified improving the potential and phase separation of chitosan-based materials, all these properties mean it is an excellent candidate for wastewater treatment.

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

“…In the past two decades, these materials used as biosorbents have received much attention in water and wastewater treatment, mainly for metal chelation and dye removal Crini 2015;Kos 2016;Muya et al 2016;Kanmani et al 2017;Kyzas et al 2017;Nechita 2017;de Andrade et al 2018;Desbrières and Guibal 2018;El Halah et al 2018;Pakdel and Peighambardoust 2018;Wilson and Tewari 2018). Indeed, chitosan has an extremely high affinity for metals and metalloids and for many classes of dyes, including direct, acid, mordant and reactive.…”

“…Indeed, chitosan has an extremely high affinity for metals and metalloids and for many classes of dyes, including direct, acid, mordant and reactive. In their comprehensive reviews, Crini (2015), Yong et al (2015), Kyzas et al (2017), Wang and Zhuang (2017), Desbrières andGuibal (2018), El Halah et al (2018) and Pakdel and Peighambardoust (2018) recently indicated that biosorption onto chitosan was a promising alternative to replace conventional adsorbents used for decolorization purposes, metal chelation or recovery, and organic removal. With nutraceuticals and cosmeceuticals, the water and wastewater treatment field seems to be the next market in the development of chitosan (Morin-Crini et al 2019).…”

Cross-Linked Chitosan-Based Hydrogels for Dye Removal

“…Indeed, chitosan has an extremely high affinity for metals and metalloids and for many classes of dyes, including direct, acid, mordant and reactive. In their comprehensive reviews, Crini (2015), Yong et al 2015, Kyzas et al (2017), Wang and Zhuang (2017), Desbrières andGuibal (2018), El Halah et al (2018) and Pakdel and Peighambardoust (2018) recently indicated that biosorption onto chitosan was a promising alternative to replace conventional adsorbents used for decolorization purposes, metal chelation or recovery, and organic removal. With nutraceuticals and cosmeceuticals, the water and wastewater treatment field seems to be the next market in the development of chitosan.…”

“…type of functional groups and degree of grafting but also to textural properties (from microspheres to nanoparticles). An overview of the literature data shows that performances strongly depend on the type of material used (Crini 2015;Yong et al 2015;Kyzas et al 2017;Wang and Zhuang 2017;Desbrières and Guibal 2018). Indeed, each material has its specific application as well as inherent advantages and disadvantages in dye removal.…”

Chitosan for direct bioflocculation of wastewater

“…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).…”