Development and regeneration of composite of cationic gel and iron hydroxide for adsorbing arsenic from ground water

Abstract

Globally, arsenic contaminated groundwater is a serious concern for human health. Previous studies have developed various methods to remove arsenic. But, most of them fail to selectively adsorb arsenic and regenerate. In this study, we developed an adsorbent, a cationic polymer gel loaded with iron hydroxide, which can adsorb arsenic from groundwater more effectively than the other adsorbents. The cationic polymer gel is N,N-dimethylamino propylacrylamide, methyl chloride quaternary (DMAPAAQ). The preparation of the gel is different from the other polymer gels used for adsorption of arsenic and other metals, and it ensures that the gel contains 53.7% FeOOH particles. It should also provide good selectivity, be simple to use and be cost-effective in terms of reusability. The study showed that the gel selectively adsorbed arsenic effectively at neutral pH levels. The results demonstrate that the maximum amount of As(V) adsorption was 123.4 mg/g, which is higher than the other adsorbents. In addition, the gel adsorbed As(V) selectively in the presence of Sulphate. Also, regeneration of the gel was performed for eight consecutive days with 87.6% effectiveness. Additionally, the adsorption mechanism of this gel composite and time required for reaching the equilibrium adsorption is discussed in this paper.