Usage of natural wastes from animal and plant origins as adsorbents for the removal of some toxic industrial dyes and heavy metals in aqueous media

Abstract

It has always been crucial to have enough water available for survival and growth; hence it is necessary to purify polluted water for reuse. In this study, contaminated water is cleansed by the adsorption of three dyes Methylene blue (MB), Congo Red (CR), and Bromocersol Green (BCG), as well as two heavy metals, chromium (VI) and zinc (II) using a low-cost adsorbent like activated carbon gotten from treated sheep remnants and barely husks. H3PO4 acid-modified adsorbents were used in adsorption tests, which involved six different parameters (pH, contact time, adsorbent concentration, sorbent dosage, temperature, and stirring speed). The optimum pH values for the adsorption of Cr (VI), Zn (II), MB, CR, and BCG onto both adsorbents were 6, 7, 4, and 6, respectively, giving equilibrium adsorption capacity values of 1.617, 1.529, 15.388, 62.401, and 288.902 mg/g, respectively. The adsorption capacity of the activated carbon increases with increasing contact time till equilibrium is established, Adsorption isotherm study was evaluated using both the Langmuir and the Freundlich isotherms to confirm the effectiveness of adsorbents made from inexpensive wastes. Furthermore, the merits of using treated natural wastes from both plant and animal origins for water purification have been confirmed. This study supports the concepts of the environmental sustainability for the earth plant.