Yin Zhibing, Liu Nian, Bian Siyao, Li Jihui, Xu Shuying, Zhang Yucang
Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources, College of Materials and Chemical Engineering, Hainan University Haikou 570228 China
Hainan Provincial Key Lab of Fine Chem, College of Materials and Chemical Engineering, Hainan University Haikou 570228 China.
RSC Adv. 2019 Dec 20;9(72):42343-42350. doi: 10.1039/c9ra06592j. eCollection 2019 Dec 18.
Catalytic oxidative pyrolysis is a promising method for the preparation of highly adsorptive biochar by introducing oxygen-containing groups. Here, a KFeO-catalyzed oxidative pyrolysis was described for enhancing the adsorption capability of areca leaf biochar toward methylene blue at low temperature. It was shown that the maximum adsorption capacity of the biochar pyrolyzed at 200 °C was greatly improved from 122.67 to 251.95 mg g with the catalysis of KFeO due to the introduction of surface oxygen-containing groups. In addition, a high adsorption capability was observed over a wide pH range for the KFeO-modified biochar and nearly neutral pH was obtained after adsorption, further demonstrating the great advantages of KFeO-catalyzed oxidative pyrolysis. Mechanistic studies revealed that the adsorption of the pristine biochar was mainly determined by hydrogen bonding and electrostatic interaction. Whereas, the adsorption of the KFeO-modified biochar was attributed to cation exchange besides hydrogen bonding and electrostatic interactions.
催化氧化热解是一种通过引入含氧基团制备高吸附性生物炭的有前景的方法。在此，描述了一种KFeO催化的氧化热解方法，用于增强槟榔叶生物炭在低温下对亚甲基蓝的吸附能力。结果表明，由于表面含氧基团的引入，在KFeO催化下，200℃热解的生物炭的最大吸附容量从122.67 mg/g大幅提高到251.95 mg/g。此外，KFeO改性生物炭在较宽的pH范围内具有高吸附能力，吸附后pH接近中性，进一步证明了KFeO催化氧化热解的巨大优势。机理研究表明，原始生物炭的吸附主要由氢键和静电相互作用决定。而KFeO改性生物炭的吸附除氢键和静电相互作用外，还归因于阳离子交换。
