Abstract Formic acid is a promising hydrogen storage material for its high H2 capacity, easy transfer and moderate H2 regeneration conditions. Active carbon supported Mo2C with or without Co doping were used as the heterogeneous catalyst in the decomposition of a high concentrated aqueous solution of formic acid up to 50% on a fixed bed reactor. For a given flow rate and reaction temperature, though higher volume of H2 is produced per unit time, the increase in formic acid’s concentration reduces both H2 selectivity and formic acid conversion rate. At 250 °C, a stream of 236 mL/min H2 was generated continuously at a high H2 selectivity (91%) and formic acid conversion rate (86%), from a 10% formic acid fed at the flow rate of 5 mL/min. High reaction temperature improved the conversion of formic acid feed at little expense of H2 selectivity. The doping of Co in the Mo2C lattice improves the H2 selectivity to 100% at 100–200 °C. A life time study showed the stability of this system by the remained high H2 selectivity in formic acid decomposition. This work of using active carbon supported molybdenum carbides and high concentrated aqueous formic acid, opens up a new route for the portable H2 generator using formic acid as a hydrogen storage material at no environmental risk.

中文翻译：

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浓甲酸水溶液在固定床反应器上大容量原位制氢

摘要 甲酸具有高H2容量、易转移和温和的H2再生条件，是一种很有前途的储氢材料。在固定床反应器上分解高达 50% 的高浓度甲酸水溶液时，使用带有或不带有 Co 掺杂的活性炭负载的 Mo2C 作为多相催化剂。对于给定的流速和反应温度，虽然每单位时间产生更多体积的 H2，但甲酸浓度的增加会降低 H2 的选择性和甲酸转化率。在 250 °C 时，从以 5 mL/min 流速进料的 10% 甲酸以高 H2 选择性 (91%) 和甲酸转化率 (86%) 连续生成 236 mL/min H2 流。分钟 高反应温度提高了甲酸进料的转化率，而 H2 选择性的代价很小。在 Mo2C 晶格中掺杂 Co，在 100-200 °C 时将 H2 选择性提高到 100%。寿命研究表明，该系统在甲酸分解中保持高 H2 选择性，因此具有稳定性。这项使用活性炭负载碳化钼和高浓度甲酸水溶液的工作为使用甲酸作为无环境风险的储氢材料的便携式氢气发生器开辟了一条新途径。