Institution: | 1.Ministry-province Jointly-constructed Cultivation Base for State Key Laboratory of Processing for Non-ferrous Metal and Featured Materials, Guangxi Zhuang Autonomous Region, Nanning, 530004, China ;2.School of Chemistry and Chemical Engineering, Guangxi University, Nanning, 530004, China ; |
Abstract: | Using molasses wastewater as partial acidifying agent, a new Fenton-like catalyst (ACRM
sm
) was prepared through a simple process of acidification and calcination using red mud as main material. With molasses wastewater, both the free alkali and the chemically bonded alkali in red mud were effectively removed under the action of H2SO4 and molasses wastewater, and the prepared ACRM
sm
was a near-neutral catalyst. The ACRM
sm
preparation conditions were as follows: for 3 g of red mud, 9 mL of 0.7 mol/L H2SO4 plus 2 g of molasses wastewater as the acidifying agent, calcination temperature 573 K, and calcination time 1 h. Iron phase of ACRM
sm
was mainly α-Fe2O3 and trace amount of carbon existed in ACRM
sm
. The addition of molasses wastewater not only effectively reduced the consumption of H2SO4 in acidification of red mud but also resulted in the generation of carbon and significantly improved the distribution of macropore in prepared ACRM
sm
. It was found that near-neutral pH of catalyst, generated carbon, and wide distribution of macropore were the main reasons for the high catalytic activity of ACRM
sm
. The generated carbon and wide distribution of macropore were entirely due to the molasses wastewater added. In degradation of orange II, ACRM
sm
retained most of its catalytic stability and activity after five recycling times, indicating ACRM
sm
had an excellent long-term stability in the Fenton-like process. Furthermore, the performance test of settling showed ACRM
sm
had an excellent settleability. ACRMsm was a safe and green catalytic material used in Fenton-like oxidation for wastewater treatment. |