Synthesis of zero-valent iron/biochar by carbothermal reduction from wood waste and iron mud for removing rhodamine B

Abstract

This study proposes a new process to synthesize zero-valent iron/biochar (Fe0-BC) by carbothermal reduction using wood waste and iron mud as raw materials under different temperature. The characterization results showed that the Fe0-BC synthesized at 1200ºC (Fe0-BC-1200) possessed favorable adsorption capacity with the specific surface area of 103.18 m2/g, and that the zero-valent iron (Fe0) particles were uniformly dispersed on the biochar surface. The removal efficiency of rhodamine B (RB) was determined to evaluate the performance of the prepared Fe0-BC. Fe0-BC-1200 presented the best performance on RB removal, which mainly ascribe to that more Fe0 particles generated at higher temperature. The equilibrium adsorption capacity reached 49.93 mg/g when the initial RB concentration and the Fe0-BC-1200 dosage were 100 mg/L and 2g/L, respectively, and the pseudo-second-order model was suitable to fit the removal experimental data. LCMC and XRD analyses revealed that the removal mechanism included the physical adsorption of biochar and the redox reaction of Fe0. Moreover, copper existed in the iron mud was also reduced to Cu0, which was beneficial to catalyze the oxidation of iron, the degradation of RB was promoted at the same time.

Hexavalent chromium elimination from wastewater by integrated micro-electrolysis composites synthesized from red mud and rice straw via a facile one-pot method

“…5 b. The weakened –OH vibration at 3432 cm −1 demonstrated that the functional groups were involved in the Cr(VI) removal, which could be reduction or formation of complexations 46 . The same phenomena were observed for the C=C and C–O stretching, indicating the different functional groups contributed to the Cr(VI) removal.…”