高岭土是煤中常见的矿物，其对煤生物甲烷的代谢过程的影响较少受到关注。选取脱矿后的褐煤和高岭土，通过生物产气模拟实验、红外光谱分析、XPS、荧光光谱和宏基因组分析来探究高岭土对煤生物产气的控制作用。结果表明：添加一定比例的高岭土能够有效促进生物甲烷的产出，其中添加6%的高岭土，生物产气量相较于原煤增加了90.4%，高岭土过多则会抑制生物甲烷的产出。高岭土使发酵系统中煤的大分子结构变化更加明显，芳香类物质被有效转化为小分子量物质；添加高岭土的发酵系统使得煤样中酚碳或醚碳进一步氧化为有机酸类物质，C—C、C—H的相对含量分别减少了2.01%和10.20%。可溶性有机质能够被有效降解和利用，进而有利于生物产气。高岭土促使微生物菌群物种丰度增加，增强了各产甲烷途径中关键酶的基因丰度，促进发酵液中各类复杂物质的降解以及甲烷的转化。研究结果为煤中赋存的高岭土对生物甲烷代谢的影响提供实验支撑。

Kaolinite is a common mineral in coal, and its influence on the metabolic process of coal biological methane is less concerned. In this study, lignite and kaolin after demineralization were selected to explore the control effect of kaolin on coal bio-gas production through bio-gas production simulation experiment, infrared spectrum analysis, XPS, fluorescence spectrum and metagenomic analysis. The results show that adding a certain proportion of kaolin can effectively promote the production of biological methane. Among them, adding 6% kaolin, the biological gas production increased by 90.4% compared with the raw coal, and excessive kaolin will inhibit the production of biological methane. Kaolin made the macromolecular structure of coal in the fermentation system change more obviously, and aromatic substances were effectively converted into small molecular weight substances. The fermentation system with kaolin addition further oxidized phenolic carbon or ether carbon in coal samples to organic acids, and the relative contents of C—C and C—H decreased by 2.01% and 10.20%, respectively. Soluble organic matter can be effectively degraded and utilized, which is conducive to biogas production. Kaolin promoted the increase of microbial flora species abundance, enhanced the gene abundance of key enzymes in each methanogenic pathway, and promoted the degradation of various complex substances in the fermentation broth and the conversion of methane. The research results provide experimental support for the influence of kaolin in coal on the metabolism of biological methane.