【摘要】 <正> 关于腐植酸(HA)热分析和热裂解的研究虽已不少,但注意力一般集中于高温区域,对250℃以下范围的讨论甚少.其实这个温区才是腐植酸制取和应用的主要范围,了解各类腐植酸在此范围内的受热变化,具有实际意义。我们用红外光谱对这一过程进行了观察,特别注意到腐植酸的主要官能团(羧基)的变化。更多还原

【Abstract】 Changes of humic acids in the temperature range below 250℃ areimportant in practice,they are studied by IR spectra.Attention is particu-larly paid to carboxylic group.There is no significant change ordinarydrying temperatures,105-110℃.Beyond 150℃,some chemical changesbecome significant and the anhydride formation begins for regeneratedhumic acids,including all fulvic acids.But in the case of original humicacids,such changes can scarcely be detected.Another important informa-tion is the appearance of a sharp band at 2340cm^-1for all humic acidsafter heating beyond 150℃.It is ascribed to CO₂ formation by decarbo-xylation of carboxylic groups.Since band at 1720cm^-1,characteristic ofCOOH group,remains not much changed up to 250℃,therefore,loss ofcarboxyl groups in decarboxylation might be partially replenished throughhot air oxidation.更多还原