Anionic dye removal from aqueous solutions using standard biochars

Abstract

One of the most serious problems related to water pollution by the textile, plastics, leather and food industries, among others, is the emission of aqueous effluents containing dyes. The most commercially used dyes are resistant to biodegradation, photodegradation and the action of oxidizing agents. The presence of dyes in water bodies can significantly and adversely affect the photosynthesis of aquatic plants by reducing the penetration of sunlight. In addition, they can be toxic to certain forms of aquatic life. Treatment of aqueous effluents containing dyes can involve a variety of materials and techniques, of which adsorption stands out for its simplicity, low cost and efficiency. In this study, standard biochars derived from wheat straw (WSP), oil seed rape straw (OSR) and Miscanthus straw (MSP), obtained at two different pyrolytic temperatures (550 °C and 700 °C), were investigated as adsorptive materials for remazol black (RB) dye. Maximum adsorption capacities were obtained at a dosage of 5 g L-1 for most of the BCs, except for MSP550, for which the dosage of 10 g L-1 achieved the highest performance. pH effect indicated that most of the adsorptive functionalities of the BCs are favored at pH 5. The steps currently in progress refer to the experimental design for the optimization of adsorption parameters and will be added in the full paper.