二甲醚水蒸气重整制氢过程的热力学分析

对二甲醚水蒸气重整制氢体系进行了热力学分析,考察了反应温度、压力、水醚进料比等因素对体系平衡组成的影响,探讨了反应体系达到热力学平衡时二甲醚转化率、氢气产物等的变化情况。分析发现,二甲醚平衡转化率分别随水醚比的增大和温度的增高而增大,随压力升高而降低;氢气组分含量分别随温度和压力的升高略有减少,随水醚比的增加先增后减。反应在水醚比为3～6、温度为200℃～300℃及压力为0.1MPa的条件下,可得到较高的氢气产率与选择性,较好的二甲醚转化率,副产物一氧化碳及甲醇含量较少。

Thermodynamic analysis of hydrogen production from dimethyl ether steam reforming

The thermodynamic analysis of hydrogen production from dimethyl ether (DME) steam reforming was carried out in order to study the influences of temperature, pressure, the mole ratio of steam to DME (S/D) on equilibrium composition. The equilibrium DME conversion and hydrogen fraction in the reaction system were analyzed. The results show that DME conversion increases with the increase of S/D and temperature, and reduces with the increase of pressure. The concentration of hydrogen decreases with the increase of temperature and pressure, and increases first and then reduces with the increase of S/D. The complete conversion of DME, higher yield and selectivity of hydrogen, and lower concentration of carbon monoxide and methanol in product can be obtained in follow reaction condition ranges: S/D of 3～6, temperature of 200～300℃ and pressure of 0.1MPa.