A sustainable and cost-effective approach for efficient removal of Direct Blue-14 azo dye from wastewater using North American Zeolite for developing countries

Abstract

North American Zeolite (NAZ) is an affordable and widely available mineral in the United States, Asia, and Africa. So, the potential for detoxifying wastewater comprising azo dyes is investigated. It has the capacity to adsorb a hazardous life-threatening, and carcinogenic direct blue 14 dye (DB-14) from water bodies. Mechanistic and operational optimization experiments demonstrated that 0.05 g of NAZ resulted in 96.4% adsorption degradation of 20 ppm DB-14 via a multilayer chemisorption process with intra-particle diffusion, as evidenced by isothermal and kinetic assessments of equilibrium data. Maximum sorption potential of NAZ for DB-14 is 122 mg g⁻¹ following pseudo-second order kinetics. The negative Gibbs free energy (ΔG^o) associated with the adsorption spontaneity behavior of DB-14 on NAZ. These promising results favor its use on commercial scale dye removal especially in poor Asian and African countries in ecofriendly and cost effective manner.