Abstract Catalytic methane pyrolysis (CMP) is an environmentally benign and promising strategy for hydrogen production. However, one of the important challenges is to creatively design and prepare catalysts with high and stable catalytic activity. To integrate both advantages of traditional metal and carbon catalysts, four effective strategies were proposed to study K2CO3-promoted CMP on nickel/coal-char hybrids in this work, including: (1) Impregnation-Thermal treatment-Mechanical mixing method, (2) Precipitation-Thermal treatment method, (3) Precipitation-In situ thermal treatment (PIT) method, and (4) Precipitation-In situ thermal treatment-Hydrogen reduction method. The results suggest that the addition of K2CO3 is the key factor to promote the catalytic activity and stability of the nickel/coal-char hybrids regardless of the preparation methods, leading to high and stable methane conversion (higher than 65% at 850 °C) in the whole 300-min CMP process. Compared to the other three preparation methods, the PIT method is considered to be one simpler and more time-saving process for synthesis of robust catalysts for CMP.

中文翻译：

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K2CO3 促进镍/煤-炭杂化物上的甲烷热解

摘要 催化甲烷热解 (CMP) 是一种环境友好且有前景的制氢策略。然而，重要的挑战之一是创造性地设计和制备具有高且稳定催化活性的催化剂。为了结合传统金属和碳催化剂的优点，在这项工作中，提出了四种有效的策略来研究 K2CO3 促进镍 / 煤 - 炭杂化的 CMP，包括：（1）浸渍 - 热处理 - 机械混合方法，（2）沉淀-热处理法，(3)沉淀-原位热处理(PIT)法，和(4)沉淀-原位热处理-氢还原法。结果表明，无论制备方法如何，K2CO3的加入都是提高镍/煤-炭杂化物催化活性和稳定性的关键因素，导致甲烷转化率高且稳定（850°C时高于65%）在整个 300 分钟的 CMP 过程中。与其他三种制备方法相比，PIT 方法被认为是一种更简单、更省时的合成 CMP 稳定催化剂的方法。