Review on decolorisation of aqueous dye solutions by low cost adsorbents

Abstract

Textile wastewater presents a challenge to conventional physico‐chemical and biological treatment methods. Liquid‐phase adsorption has been shown to be highly efficient for the removal of dyes and other organic matters from process or waste effluent. Many different types of adsorbent are used to remove colour from wastewater among which the most widely used material is activated carbon. Since activated carbon is expensive and necessitates regeneration, attempts have been made to substitute alternatives that are biodegradable, low cost and/or waste materials. This article presents the investigations carried out by numerous researchers on the use of different kinds of adsorbents and their adsorption capacities for the removal of specific dyes from textile wastewater.

Adsorption of Acid Dyes onto Bentonite and Surfactant-modified Bentonite

“…However, adsorption is known to be one of the most effective techniques to eliminate dyes from water. Activated carbon has been familiarized as adsorbent due to its great sorption capacity for the dyes [4]. However the high cost has led us seeking for low-cost sorbents.…”

Remoção dos corantes azul brilhante, amarelo crepúsculo e amarelo tartrazina de soluções aquosas utilizando carvão ativado, terra ativada, terra diatomácea, quitina e quitosana: estudos de equilíbrio e termodinâmica

“…[1][2][3][4] Sabe-se que efluentes contendo corantes são muito difíceis de tratar, uma vez que estes são moléculas recalcitrantes, resistentes à digestão aeróbia e estáveis a agentes oxidantes. 4 Outra dificuldade é o tratamento de efluentes contendo baixas concentrações de moléculas de corantes.…”

Efficiency of Activated Carbon Prepared from Banana Peels for Treatment of Heavy Metal Ions from Waste Water

“…There are two processes for the preparation of activated carbon: physical activation and chemical activation. Physical activation includes carbonization of a carbonaceous materials followed by treatment by activated reagent like CO 2 or steam Sanghi and Bhattacharya, 2002;Bouchelta, 2008). In chemical activation, a raw material is impregnated with an activating reagent such as ZnCl 2 , H 3 PO 4 , KOH etc.…”