Zhu Hao, Zou Haiming
Department of Resource and Environment, Anhui Science and Technology University Fengyang 233100 People's Republic of China
RSC Adv. 2022 Sep 22;12(41):27002-27011. doi: 10.1039/d2ra04263k. eCollection 2022 Sep 16.
In this work, KMnO-modified biochar was prepared from spirulina residue as the research object. Herein, we report the synthesis, characterization, and catalytic degradation performance of KMnO-modified biochar, given that heterogeneous catalytic oxidation is an effective way to treat dye wastewater rapidly. The Mn/SRBC catalyst prepared by KMnO modification was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffractometry, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption and laser Raman spectroscopy. In addition, we compared the results with that of the unmodified SRBC. The results showed that the Mn/SRBC catalyst prepared by KMnO modification had a rich pore structure, which provided sufficient contact area for the catalytic reaction. In the presence of HO, the catalyst could be used to catalyze the oxidative degradation of malachite green in aqueous solution with ultra-high efficiency. In the experiment, the initial pH values of the reaction system had a significant influence on the reaction rate. The removal effect of biochar on the malachite green was poor in an alkaline environment. Within a specific range, the removal rate of malachite green was proportional to the concentration of HO in the reaction system. The degradation rate of malachite green dye at 8000 mg L was about 99% in the presence of the catalyst over 5 mmol L hydrogen peroxide for 30 min. These results show the potential application of algae residue biochar and carbon-based composite catalysts for degrading and removing dye wastewater.
在本工作中，以螺旋藻残渣为研究对象制备了高锰酸钾改性生物炭。鉴于多相催化氧化是快速处理染料废水的有效方法，在此我们报告了高锰酸钾改性生物炭的合成、表征及催化降解性能。采用扫描电子显微镜、透射电子显微镜、X射线衍射仪、X射线光电子能谱仪、傅里叶变换红外光谱仪、氮气吸附-脱附仪和激光拉曼光谱仪对通过高锰酸钾改性制备的锰/螺旋藻残渣生物炭催化剂进行了表征。此外，我们将结果与未改性的螺旋藻残渣生物炭进行了比较。结果表明，通过高锰酸钾改性制备的锰/螺旋藻残渣生物炭催化剂具有丰富的孔结构，为催化反应提供了足够的接触面积。在过氧化氢存在的情况下，该催化剂可用于高效催化水溶液中孔雀石绿的氧化降解。在实验中，反应体系的初始pH值对反应速率有显著影响。在碱性环境中生物炭对孔雀石绿的去除效果较差。在特定范围内，孔雀石绿的去除率与反应体系中过氧化氢的浓度成正比。在5 mmol/L以上过氧化氢存在下，催化剂作用30 min，8000 mg/L孔雀石绿染料的降解率约为99%。这些结果表明了藻类残渣生物炭和碳基复合催化剂在降解和去除染料废水中的潜在应用。
