静电纺丝制备中空纤维原位固定化碳酸酐酶用于二氧化碳的吸收

摘要

Carbonic anhydrase catalyzed bio-sequestration of CO2 to form HCO-3 , followed by trapping as solid CaCO3 is one of the most promising technologies for CO2 capturing. The effects of reaction condition on the CO2 hydration using free carbonic anhydrase were systematically investigated. In order to improve the stability of the enzyme and facility its recycling, the carbonic anhydrase was in situ encapsulated inside hollow fibers via a novel co-axial electrospinning technology. Compared with the free enzyme, the immobilized carbonic an-hydrase showed much improved thermal stability and suffered much reduced inhibitory effects from cation ions, such as Cu2+ and Fe3+. After 11 reuses, the immobilized enzyme retained about 81. 9% of its original activity by comparing the amount of formed CaCO3 precipitation. In the presence of immobilized carbonic anhydrase, both calcite and vaterite CaCO3 solid were formed;while in the absence of enzyme or with free carbonic anhy-drase, only calcite CaCO3 was observed.%考察了游离碳酸酐酶吸收CO2水合体系反应条件，并通过同轴共纺静电纺丝技术制备出中空结构纤维，实现了碳酸酐酶在中空纤维中的原位包埋，提高了酶的稳定性并便于回收和重复利用.实验结果表明，固定化碳酸酐酶的热稳定性显著增强，受Cu2+和Fe3+等金属离子的抑制作用大幅度降低.连续使用11次后所生成的CaCO3沉淀量仍能达到首次使用的81.9%.固定化酶体系生成的CaCO3沉淀包括方解石型和球文石型2种晶形，而无酶和加入游离碳酸酐酶的反应体系则主要生成方解石型CaCO3沉淀.