钾修饰水滑石吸附剂脱碳性能及颗粒强度实验研究

Experimental Study of CO_2 Capacity and Mechanical Strength of K-Promoted Hydrotalcite Adsorbent

中温固体吸附剂分离H_2/CO_2技术是煤化工水气变换过程中的重要技术,可同时实现显热H_2的利用及CO_2的集中捕集。其中关键为寻找合适中温下CO_2成型吸附剂的开发。本研究了成型过程中原位引入铝溶胶、碳酸钾及其添加条件对钾修饰水滑石吸附量、颗粒强度的影响规律,通过X射线衍射实验初步揭示了成型过程中钾修饰拟薄水铝石的形成过程,通过热重实验分析了钾修饰拟薄水铝石对吸附量的增加。挤出成型批次化颗粒吸附剂具有0.77 mmol/g CO_2吸附能力,同时相比于未加入碳酸钾时增加了约39%颗粒强度。

H2/C02 separation by solid sorbents at medium temperature range is an essential technology in water-gas-shift reaction process of coal chemical chemistry, which could utilize sensible heated H2 and capture CO2 simultaneously. The development of suitable shaped C02 adsorbent is a key point to put this technology into practice. In this research, the effects of several introduction methods of alumina sol and potassium carbonate in shaping process on the C02 capacity and mechanical strength of K-promoted hydrotalcite pellets are studied. X-ray diffraction is applied to demonstrate the forming process of K4promoted pseudo boehmite in forming stage and thermal gravimetric method is employed to analysis the enhancement of C02 capacity from K-promoted pseudo boehmite. Adsorbent pellets extruded in batches have a CO2 capacity of 0.77 mmol/g, also enjoy a 39% increase of mechanical strength compared with pellets without adding potassium carbonate.