Optimisasi Adsorpsi Ion Pb(II) Menggunakan Zeolit Alam Termodifikasi Ditizon

Abstract

Lead (Pb) is one of heavy metals pollutants in the environment. Adsorption appears to be the most widely used for removal of the heavy metals. The aim of this research is to improve the performance of zeolite by modification using chelating agent diphenyltiocarbazone (dithizone) to remove Pb(II) from aqueous solution. The effect of various variables, such as, pH, amount of adsorbent, concentration of Pb, and contact time was investigated using batch process. The best mass of adsorbent for modified zeolite was 0.2 g. The best conditions for modified zeolite was obtained at pH 6, concentration of Pb(II) 300 ppm, and contact time 60 minutes. Meanwhile, the best performance of the unmodified zeolite was at pH 4, concentration of Pb 250 ppm, and contact time 60 minutes. The modified zeolite showed higher adsorption capacity than that of the unmodified material. The results revealed that the adsorption behavior of Pb(II) on the both adsorbent fitted well with the Langmuir model. In addition, the mean adsorption energy from the Dubinin-Radushkevich isotherm indicated that the adsorption process was physisorption.