Novel iron manganese oxide modified mulberry biochar for the adsorption of phosphorus in aqueous solution
Meina Liang, Liling Yan, Dunqiu Wang, Cheng Xu, Zhenliang Deng, Shuiping Xu, Sen Li
Abstract
ABSTRACT The modified iron manganese oxide modified mulberry biochar (IMOM-BC) sorbent was prepared by chemical oxidation and coprecipitation. Scanning electron microscope, Fourier-transform infrared spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were employed to analyze the adsorption mechanism of IMOM-BC for phosphorus. The effects brought by different pH values, adsorbent dosages, contact time, and coexisting ions on the adsorption were investigated. The results show that IMOM-BC with pH 2.0 can adsorb phosphorus best, and with a dosage of 2.0 g/L, the removal rate of phosphorus can reach 99.85%. Here the adsorption effect for coexisting ions of phosphorus is CO 3 2– > SO 4 2– > NO 3 – . The Langmuir isotherm adsorption model can be referred to explain the adsorption process of phosphorus by IMOM-BC. At 25°C, 35°C, and 45°C, the maximum adsorption capacity for phosphorus were 23.09, 25.32, and 26.34 mg/g, respectively. The iron, manganese oxide, surface hydroxyl, and phenolic hydroxyl groups of IMOM-BC are found to be involved in the adsorption, and the adsorption of phosphorus by IMOM-BC is considered to be mainly chemical adsorption.