Citric and Tartaric Acids Effect on Zn<sup>2+</sup> Desorption in the Soil around Textile Industry Area-Yogyakarta

Abstract

Study of physico-chemical properties, adsorption and desorption of Zn using citric acid and tartaric acid on the textile industrial area has been carried out. This study aims to analyze the physico-chemical character of the soil and the content of heavy metals around the textile industry which is suspected of being contaminated by waste, the adsorption isotherm and capacity of Zn, the desorption kinetics of Zn using citric acid and tartaric acid solutions. Soil samples were divided into three sample points based on the location where they were taken, namely sample points I, II and III. The physical and chemical properties of soil were measured, included pH, ash content, electrical conductivity, total organic carbon, cation exchange capacity and content of heavy metals The adsorption capacity was studied by the adsorption of Zn on the soil. Meanwhile, the desorption was studied by using both citric and tartaric acid solution. The results showed that sample I had the highest total organic carbon content of 692.3 mg g-1, and a cation exchange capacity of 42.0 cmol+ kg-1 with a metal content of 735.0 mg kg-1. The maximum adsorption capacity of Zn is 708.7 mg kg-1. The optimum desorption using citric acid occurs at a concentration of 0.6 mol L-1, pH 3 and a time of 7 h, while tartaric acid occurs at a concentration of 0.8 mol L-1, pH 3 and a time of 7 h. Keywords: citric acid, tartaric acid, physico-chemical properties, zinc