Sorption-enhanced hydrogen production: A review
Sorption-enhanced hydrogen production: A review
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DOI：
10.1021/ie800298z
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发表时间：
2008-09-03
影响因子：
4.2
通讯作者：
Harrison, Douglas P.
中科院分区：
文献类型：
--
作者：
Harrison, Douglas P.
在吸附增强的制氢方法中，烃重整、水煤气变换和CO2分离反应在与CO2吸附剂混合的重整催化剂上在单个反应步骤中同时发生。当CO2从气相形成时将其转移到固相改变了正常平衡限制，并允许重整和水煤气变换反应接近完成。取决于反应条件，产物（干基）可含有多达98%的H-2和仅ppmv水平的CO和CO2，从而最小化最终H-2纯化步骤或对于某些应用甚至消除它。已经研究了许多CO2吸附剂，包括钙基氧化物、K促进的水滑石以及锂和钠的混合金属氧化物。吸附剂在H-2生产过程中被消耗，因此该过程本质上是不稳定的。工艺经济性要求吸附剂是可再生的，并用于许多反应-再生循环。再生可以通过温度摆动、压力摆动或组合进行。目前的大部分研究都致力于测试和改善吸附剂的多组分耐久性。循环流化床反应器和具有交替反应-再生功能的双固定床反应器都已被提出来提供整体稳态H-2生产。
In the sorption-enhanced hydrogen production process, hydrocarbon reforming, water gas shift, and CO2 separation reactions occur simultaneously in a single reaction step over a reforming catalyst mixed with a CO2 sorbent. Transferring CO2 as it is formed from the gas to the solid phase shifts the normal equilibrium restrictions and allows both the reforming and water gas shift reactions to approach completion. Depending on reaction conditions, the product (dry basis) may contain as much as 98% H-2 and only ppmv levels of CO and CO2, thereby minimizing the final H-2 purification step or even eliminating it for some applications. A number of CO2 sorbents have been studied including calcium-based oxides, K-promoted hydrotalcite, and mixed metal oxides of lithium and sodium. The sorbent is consumed during H-2 production so that the process is intrinsically unsteady state. Process economics requires that the sorbent be regenerable and used in many reaction-regeneration cycles. Regeneration may occur via temperature swing, pressure swing, or a combination. Much of the current research is devoted to testing and improving sorbent multicycle durability. Both circulating fluid-bed reactors and dual fixed-bed reactors with alternating reaction-regeneration functions have been proposed to provide overall steady state H-2 production.