The efficiency of cleaning agents at different temperatures in soil washing process for arsenic contamination

The use of heavy metals especially arsenic, lead, cadmium and mercury has led to extensive contamination of soils worldwide. Arsenic, however, is mostly noted because of its carcinogenic and mutagenic characteristics occurred due to the agricultural and industrial activities and the invasion of domestic and industrial wastewater into the soil environment. In this research, the removal efficiency of arsenic by use of soil washing process was assessed and diverse cleaning agents and also temperatures were applied. Water, Ethylene Diamine Tetraacetic Acid (EDTA), Sodium Dodecyl Sulphate (SDS) and a mixture of EDTA and SDS were chosen as the agents to treat the contaminated samples. Regarding the analysis results, it could be observed that efficacy of water, EDTA, SDS, and the mixture solution of SDS and EDTA at 20˚C is 20.82%, 45.21%, 37.93%, and 79.48%, respectively. These results were determined as 24.75%, 52.34%, 40.83%, and 79.48%for treated samples at 50˚C, correspondingly. Consequently, the efficiency of soil washing solutions in the removal of arsenic (at 20˚C and 50˚C) is specified as: "Mixture of EDTA and SDS" ›› "EDTA" ›› "SDS" ›› "Water". Additionally, the investigation of the results showed that by increasing the temperature, the effectiveness of soil washing process would be enhanced.