碳化氨水中含碳量的分析及测量

Analysis and measurement of carbamate,carbonate and bicarbonate in carbonated aqueous ammonia solution

近年来氨法吸收二氧化碳成为化学吸收方法捕集二氧化碳研究方面的热点,碳化氨水中含碳离子的测定至今仍然是一个难点。该文使用0.1 mol/L的H2SO4溶液和Metrohm 809 Titrando滴定仪,经过对多个碳化氨水溶液样品的滴定测量,并且结合质量守恒法和BaCl2沉淀法进行比较,发展和确认了能够测量出碳化氨水溶液中含氨量和含碳量的滴定方法。对滴定过程进行了深入的分析,认为美国能源实验室(NETL)发展的NH3、CO32-、HCO3-测量方法存在问题。滴定方法相对于Raman光谱和NMR方法的缺点是无法区分含碳离子形态,但优点是能够快速准确地测定碳化氨水中的含氨量和含碳量。

Aqueous ammonia solution is considered to be an effective and economic absorbent for CO2 capture in recent years,but the ion identification（related to carbamate,carbonate and bicarbonate） is difficult after CO2 dissolving into aqueous ammonia solution.A titration method was developed to determine the total CO2 and total ammonia in the solution using 0.1 mol/L H2SO4 and Metrohm 809 Titrando.The method shows good accuracy compared with the mass balance method and the BaCl2 precipitation method.The titration process was analyzed in detail,which shows that the titration method developed by the National Energy Technology Laboratory（NETL） of the U.S.Department of Energy is questionable.The titration method in this paper cannot determine the concentration of carbamate,carbonate and bicarbonate,respectively,compared with the Raman and NMR spectroscopy methods,but the total CO2 and total ammonia can be determined quickly and accurately according to the titration profile of pH.