A phosphomolybdic acid promoted oxidative pyrolysis was described for preparation of banana pseudostem biochar. The strategy succeeded to introduce oxygen-containing groups onto the biochar surface at low temperature. In addition, pore channels were created, demonstrated by the SEM images of biochar prepared at 200 °C. Adsorption experiments showed that the biochar pyrolyzed at 200 °C exhibited much better adsorption capability than others pyrolyzed at higher temperatures for methylene blue (MB). The adsorption capability of biochar prepared at 200 °C was enhanced from 87.28 to 146.23 mg/g at 45 °C with phosphomolybdic acid modification. The enhancement of adsorption capacity could be ascribed to the increase of surface oxygen-containing functional groups and pore channels. In-situ generated carboxylic groups during adsorption and desorption played an important role in removal of MB. Adsorption of MB was mainly attributed to hydrogen bonding, electrostatic interactions and cation exchanges.

中文翻译：

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一种增强香蕉假茎生物炭对亚甲基蓝低温吸附能力的改进方法


描述了磷钼酸促进的氧化热解用于制备香蕉假茎生物炭。该策略成功地在低温下将含氧基团引入生物炭表面。此外，还创建了孔隙通道，并通过 200 °C 下制备的生物炭的 SEM 图像证明了这一点。吸附实验表明，在200℃下热解的生物炭对亚甲基蓝（MB）的吸附能力比在更高温度下热解的其他生物炭表现出更好的吸附能力。通过磷钼酸改性，200℃制备的生物炭的吸附能力从87.28 mg/g提高到45℃的146.23 mg/g。吸附能力的增强可归因于表面含氧官能团和孔道的增加。吸附和解吸过程中原位生成的羧基对MB的去除起到了重要作用。 MB的吸附主要归因于氢键、静电相互作用和阳离子交换。