Thermodynamic analyses of adsorption-enhanced steam reforming of glycerol for hydrogen production
Thermodynamic analyses of adsorption-enhanced steam reforming of glycerol for hydrogen production
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DOI：
10.1016/j.ijhydene.2009.06.070
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发表时间：
2009-09
影响因子：
7.2
通讯作者：
Haisheng Chen;T. Zhang;B. Dou;V. Dupont;Paul T. Williams;M. Ghadiri;Yulong Ding
中科院分区：
文献类型：
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作者：
Haisheng Chen;T. Zhang;B. Dou;V. Dupont;Paul T. Williams;M. Ghadiri;Yulong Ding
基于吉布斯自由能最小化原理，对甘油吸附强化水蒸气重整制氢进行了非化学计量热力学分析。考察了温度（600- 1000 K）、压力（1- 4 bar）、水甘油比（3：1-12：1）、CO_2吸附率（0-99%）和载气与原料摩尔比（1：1-5：1）对重整反应和积炭的影响。结果表明，CO2吸附剂的使用提高了甘油转化为氢气的转化率，每摩尔甘油产生的最大氢气摩尔数可从6增加到7。分析表明，在有CO2吸附剂存在下，甘油-水蒸汽重整反应的最佳温度为800 ~ 850 K，比无CO2吸附时的最佳温度低100 K左右。虽然高压有利于CO2吸附，但较低的操作压力可提高总的氢气转化率。发现最有利的水与甘油进料比为10.90，高于该比，益处变得微不足道。碳的形成可能发生在低的水与甘油进料比下，并且CO2吸附剂的使用可以抑制形成反应并显著降低用于碳形成的水与甘油进料比的下限。
A non-stoichiometric thermodynamic analysis is performed on the adsorption-enhanced steam reforming of glycerol for hydrogen production based on the principle of minimising the Gibbs free energy. The effects of temperature (600–1000K), pressure (1–4bar), water to glycerol feed ratio (3:1–12:1), percentage of CO2adsorption (0–99%) and molar ratio of carrier gas to feed reactants (1:1–5:1) on the reforming reactions and carbon formation are examined. The results show that the use of a CO2adsorbent enhances glycerol conversion to hydrogen and the maximum number of moles of hydrogen produced per mole of glycerol can be increased from 6 to 7 due to the CO2adsorption. The analyses suggest that the most favourable temperature for steam–glycerol reforming is between 800 and 850K in the presence of a CO2adsorbent, which is about 100K lower than that for reforming without CO2adsorption. Although high pressures are favourable for CO2adsorption, a lower operating pressure gives a higher overall hydrogen conversion. The most favourable water to glycerol feed ratio is found to be ∼9.0 above which the benefit becomes marginal. Carbon formation could occur at low water to glycerol feed ratios, and the use of a CO2adsorbent can suppress the formation reaction and substantially reduce the lower limit of the water to glycerol feed ratio for carbon formation.