二氧化碳捕集中2-氨基-2-甲基-1-丙醇溶剂的热降解

Thermal degradation of 2-Amino-2-methyl-1-propanol solvent for carbon dioxide capture

2-氨基-2-甲基-1-丙醇(AMP)水溶液及AMP与其他有机胺的混合溶液被认为是一类具有商业应用前景的二氧化碳捕集吸收剂.在使用有机胺捕集二氧化碳的工艺中,胺的降解性质是评价胺的重要因素之一.在密闭间歇玻璃高压釜中研究了AMP的热降解,利用阳离子色谱对降解样品中AMP的浓度进行了测定.在温度低于140℃及氮气氛围的实验条件下,仅仅由温度引起的AMP热降解可以忽略.实验结果表明,二氧化碳的存在能导致AMP明显降解,但AMP降解速率比相同条件下一乙醇胺(MEA)的降解速率要低.AMP的热降解速率随二氧化碳装载量的增大而增大.通过气相色谱-质谱联用仪对AMP主要热降解产物进行了表征,并对二氧化碳引起的AMP热降解的可能机理进行了讨论.

Aqueous 2-amino-2-methyl-1-propanol （AMP） solution and the blends of AMP with other amines appear to be commercially attractive solvents for post-combustion carbon dioxide capture.Thermal degradation of AMP in the presence of carbon dioxide was investigated in a closed-batch reactor.Concentration of AMP in the degraded samples was measured by cation chromatography.The thermal degradation of AMP without carbon dioxide loading can be disregarded under nitrogen at temperatures less than 140 ℃.However,carbon dioxide is a strong catalyst for thermal degradation of AMP.The results show the thermal degradation rate of AMP is smaller than that of monoethanolamine （MEA） at the identical conditions; the thermal degradation rate of AMP increases with increasing carbon dioxide loadings.The major degradation products including 4,4-dimethyl-2-oxazolidinone,were identified by gas chromatography-mass spectrometry（GC-MS）.A possible degradation pathway was proposed to account for the identified products.