Removal of Azo Dyes from Aqueous Effluent Using Bio-Based Activated Carbons: Toxicity Aspects and Environmental Impact

Rapid growth in various industrial fields has introduced a series of new environmental risks. The textile industry is one of the major industries that is influenced by rapid advancements in technological sectors. The development in textile dying technologies has presented new types of dyes that are toxic to the ecosystem. Azo dyes are the main artificial dyes used in textiles, food, and other applications. Typically, these dyes are introduced into the environment as wastewater discharged from factories. The discharged influence penetrates the ecosystem and causes deadly diseases to human and animals. Several studies present activated carbon as a proper solution to eliminating the presence of azo dyes in the environment. However, various types of azo dye have different properties and chemical structures. Thus, there is a crucial need for more studies on the application of activated carbons to eliminate the presence of azo dyes in the environment. This paper discusses the toxic effects of azo dyes on the environment and human health. Moreover, this work presents a general review of the preparation of activated carbon and the parameters that influence the adsorption performance.