Title: Comparison of removal of chromium (III) from aqueous solution by two kinds of modified diatomite: manganese-oxide-modified diatomite and microemulsion-modified diatomite
Authors: Er Li, Xiangying Zeng, Yuehua Fan
Addresses: Wuhan Municipal Engineering Design and Research Institute, Changqing Road 40, Jianghan District, Wuhan 430000, PR China. ' Wuhan Municipal Engineering Design and Research Institute, Changqing Road 40, Jianghan District, Wuhan 430000, PR China. ' School of Environment Science and Engineering, Huazhong University of Science and Technology (HUST), Luoyu Road 1037, Hongshan District, Wuhan 430074, PR China
Abstract: Crude Diatomites Modified by Microemulsion (DMM) and manganese oxide (MnD) are tested for the removal of chromium (III) in this study. The results indicate that zero point of charge (pHZPC) of DMM is 4.7 and that of MnD is 4.6. Both DMM and MnD show remarkable increase in the sorption capacity of chromium (III) when compared with untreated diatomite, and the removal of chromium (III) by DMM is higher than that by MnD. In the case of pH on the heavy metal removal rate, both maximum percentage removal by MnD and DMM take place at nearly pH = 4, and decline when pH > 4. In addition, the increment in chromium synthetic solution concentration results in the improvement of the sorption capacity by both MnD and DMM. 36 h for MnD and 24 h for DMM are optimal equilibrium time for maximum removal.
Keywords: diatomite; manganese oxide; microemulsion; chromium removal; aqueous solutions; sorption capacity; environmental pollution; heavy metals; water pollution; water quality.
International Journal of Environment and Pollution, 2010 Vol.41 No.3/4, pp.326 - 335
Published online: 14 May 2010 *Full-text access for editors Access for subscribers Purchase this article Comment on this article