Removal of Arsenic From Water With Low Cost and Environmentally-benign Adsorbents

Abstract

Arsenic, which is widespread in receiving environments through natural and anthropogenic sources, is one of the most important problems encountered in ground and surface waters in terms of public health in recent years due to its toxic and carcinogenic properties. In this study, the adsorptive removal of arsenic was investigated by using low cost and environmentally-benign adsorbents obtained from natural and waste materials. For this purpose, pumice was chosen as natural material, red mud and steel slag were chosen as waste material. The influence of contact time and adsorbent dosage was investigated using batch tests. 50-95% arsenic removal was achieved with tested adsorbents. Modified Freundlich isotherm was found to provide the best fits to experimental data. Experimental studies have shown that steel slag is the most effective adsorbent in arsenic removal and has a maximum adsorption capacity of 3.058 mgAs g-1. The high arsenic adsorption capacity of the steel slag can be attributed to the high content of iron and calcium oxide. The present study results show that steel slag can be good alternative to commercial activated carbons for the adsorptive removal of arsenic. Moreover, the reuse of this waste material will also provide a double-side environmental benefit in an inexpensive and effective way.