Study on Adsorption of As(III) by a New Bio-Material from Chitin Pyrolysis

Abstract

Chitin-char is obtained from fast pyrolysis of chitin. To obtain the maximum surface area, chitin-char is treated by nitric acid. Then, a kind of new arsenic removal bio-material is prepared by loading Ca(OH)2 on the char (called Ca(OH)2-char). IR spectroscopy before and after char treatment reveal at least three distinct patterns of peak changes. An adsorption study is performed at different doses, pHs, and coexisting ions in the batch mode. The adsorption kinetics follows two first-order equations. Kinetic studies yield an optimum equilibrium time of 2 h with an adsorbent dose of 0.4 g/L and concentration of 10 mg/L. Using only 0.4 g/L of carbon, the maximum removal capacity is about 99.8%. The result indicates that the Ca(OH)2-char has a high adsorption capacity in the process of removing arsenic (III).

Keywords

• bio-materials
• arsenic
• adsorption
• water treatment