BIOSORPTION OF HEAVY METALS FROM THE MULTI-COMPONENT SYSTEMS OF THE GALVANIC INDUSTRY USING BREWER’S GRAIN AS ADSORBENTS

Abstract

Wastewaters from the galvanization process contain high concentrations of heavy metals representing a great danger to human health as well as to the environment. Heavy metals in the galvanization process are used in the coating process, whereby the coatings of certain metals are formed. The treatment of wastewaters generated by the galvanization process can be conducted by a number of methods, however, today more research is being done on processes which are efficient, economical and cost-effective, but environmentally acceptable. One of those techniques is adsorption. The adsorption process of Cd²⁺, Ni²⁺ and Cr²⁺ions from galvanization water using brewer’s grain as the adsorbent, at different pH values and adsorbent granulation of 0.5 mm is analyzed in this paper. The percentage of moisture and ash was determined, and the FTIR analysis was performed confirming the presence of certain functional groups. Based on the obtained values, it has been shown that the brewer’s grain can be successfully used as a natural adsorbent to remove Cd²⁺, Ni²⁺ and Cr²⁺ ions from galvanization waters, and also that high level of efficiency is obtained at all analyzed pH values. The analysis has also shown that the affinity of adsorbents to Cd²⁺, Ni²⁺ and Cr²⁺ ions is in correlation with physical and chemical properties, but that the best removal efficiency is achieved at the pH 4 value