泥岩有水热解产生低分子量有机酸实验研究

Experimental study on the generation of low molecular organic acids from mudstone by hydrous pyrolysis

直接采用泥岩岩屑进行有水热解,测定实验后水溶液中几种常见低分子量有机酸。结果表明,在实验的水溶液中检测到了丰富的低分子量有机酸,组成上主要为一元羧酸,其中又以乙酸占优势。讨论了不同热解条件对有机酸产率以及组成的影响。实验结果表明,有机酸总量随加热温度和时间增加而增加,并且溶液中不同有机酸相对组成也发生变化。当温度高于100℃,部分有机酸,主要为草酸和乙酸,开始脱羧。加热时间超过240 h(10 d)后,有机酸的产率增加不大。水溶液pH≥9可以减少低分子量有机酸的挥发损失,并可促进有机酸的生成。

Hydrous pyrolysis of the mudstone cutting was carried out and several common low molecular organic acids were measured in the experimental aqueous solution. The results showed that abundant low molecular organic acids were detected in the aqueous solutions, which were dominated by monocarboxylic acids, especially acetic acid. The influences of different experimental conditions on yield and composition of organic acids were discussed. The results showed that yield of total organic acids increased with the heating temperature and time, and relative compositions of different organic acids in solution also changed. When the heating temperature was higher than 100 ℃, parts of the organic acids, mainly including oxalic acid and acetic acid, began to decarboxylate. After the heating time was over 240 hours （10 days）, the yield of organic acids had no obvious increase. pH≥9 of aqueous solution could reduce the loss of low molecular organic acids and promote the formation of organic acids during pyrolysis.