摘要
将SetaramBT2.15微量热仪温度控制系统成功引入恒定容积法,系统测定了低温条件下CH_4,C_2H_4和C_2H_6在甲醇中的溶解度。通过对CO_2在甲醇中溶解度数据的测量,验证测量装置的可靠性。结果表明:在-20—-30℃,CH_4,C_2H_4和C_2H_6在甲醇中的溶解度随温度降低而升高,随分压升高而增大,且CH_4和C_2H_4的溶解度在所测条件下符合亨利定律;而C_2H_6的溶解度在压力升高后,溶解度与压力不符合线性关系。通过PC-SAFT状态方程对所测气体溶解度进行热力学计算,结果表明PC-SAFT状态方程能够很好地关联CH_4,C_2H_4和C_2H_6在甲醇中的溶解度,并可准确描述气体溶解度随温度、压力的变化趋势,所得热力学模型可用于低碳烃吸收的工艺计算中。
The solubility of CH_4, C_2H_4 and C_2H_6 in methanol at low temperature and high pressure conditions was determined systematically by constant volume method which was improved by the Setaram BT2.15 temperature control system. The reliability of the determined device was verified by measuring the solubility of CO_2 in methanol. The results indicate that at-20 ℃ to-30 ℃,low temperature and high partial pressure are favorable to the dissolution of CH_4, C_2H_4 and C_2H_6 in methanol and the solubility of CH_4 and C_2H_4 accords with Henry′s law under the measured conditions. However, the solubility of C_2H_6 is not linear with the pressure rising. The PC-SAFT thermodynamic model was also used to calculate the solubility of lower hydrocarbon in methanol. The calculated results are in agreement with the solubility of CH_4, C_2H_4 and C_2H_6 and the PC-SAFT can accurately describe the variation of gas solubility with different temperatures and pressures. The PC-SAFT thermodynamic model can be applied to describe the lower hydrocarbon absorption behavior in methanol.
引文
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