Handoko Darmokoesoemo, Eko Prasetyo Kuncoro, Ganden Supriyanto, Yosephine Sri Wulan Mahuhara and Pradika Annas Kuswanto
Abstract
This research aimed to study the difference and the optimum adsorption efficiency value based on the effect of pH in the adsorption of lead (II) by silica-immobilized solid waste of tofu in batch method, study the adsorption efficiency based on the effect of bed depth and flow rate in the adsorption on a continuous reactor, and study the characteristic of adsorbentâs functional groups which involved in adsorption. Variation used on pH solution was 2, 3, 4, 5, and 6. Height variation of adsorbent used was 2 cm and 4 cm. Variation used on flow rate was 5 and 10 mL/min. The characteristic of adsorbentâs functional groups was tested by FTIR before and after contact with lead (II) metal. The statistical analysis was performed on the determination of optimum pH by using Kolmogorov-Smirnov test followed by Kruskal-Wallis and Mann-Whitney test.The data analysis in this research was using descriptive analysis, showed by graphs and Tables. Meanwhile,the pHPCZ was 8.4. The statistical results showed that there was an efficiency differences based on variation of pH with 58.67% maximum efficiency at pH 6. The removal efficiency of Pb (II) in continuous flow column for the adsorbent height variation 2 cm and 4 cm which were 51.18% and 55.95% respectively. The removal efficiency of Pb (II) in continuous flow column for the flow rate 5 mL/min and 10 mL/min each by 51.18%and 44.76%. The result of FTIR analysis of the adsorbent conducted before and after the adsorption shown that there were functional groups of C=O (before vibrate strongly at 1651.07 cm-1 and after at 1633.76 cm-1),Si-O-Si (before at 1087.85 cm-1 and after at 1089.82 cm-1), O-H (before at 3425.58 cm-1 and after at 3427.62 cm-1), and N-H (before at 1543.05 cm-1, 1527.65 cm-1 and after at 1541.18 cm-1). While, the result of the FTIR analysis after the adsorption shown that there were Si-O-Pb (956.84 cm-1) and Pb-N (459.07 cm-1).