China University of Mining and Technology (Beijing)

为研究测定低阶煤中羧基含量的条件,采用离子交换法在不同的离子交换时间、润湿剂条件和预处理方式下测定宝日褐煤和平朔长焰煤中羧基的含量,研究了其对测定结果的影响规律。结果表明:可以通过延长离子交换时间使离子交换反应完全,离子交换时间大于15 h后测定结果趋于稳定;离子交换时间较短时润湿剂促进润湿作用明显,随离子交换时间延长,润湿剂的作用减弱;预先酸浸可排除无机杂质对试验结果的干扰,测定结果更为准确。

In order to determine the carboxyl groups content in low- rank coals accurately, ion exchange methods was taken to determine the carboxyl groups in Ba ori brown coal and Pingshuo long flame coal. The effect of ion exchange time, wetting agent ( methanol) and pre- acid- extraction was researched. It was concluded tha t the ion exchange could get completed when ion exchange time was prolonged. The quantity of carboxyl groups detected stay constant when ion exchange time was m ore than 15 hours. The effect of wetting agent was obvious when ion exchange time was short. While, as the ion exchange time was prolonged, its effect got less obviou s. The error caused by inorganic substance could be eliminated by pre- extracting with acid, which made the results more accurate.