CO-超临界水条件下硅灰石矿化隔离CO_2实验

CO_2 sequestration by wollastonite mineral carbonation in CO-supercritical water system

对CO-超临界水制氢条件下硅灰石直接矿物碳酸化隔离制氢过程中产生的CO2进行了实验研究,考察了温度、压力及硅灰石的加入等对反应的影响.结果表明:硅灰石可以在CO-超临界水条件下对反应过程中生成的CO2进行矿物碳酸化固定.温度和CO初压的增加,可以促进H2产率的提高,同时也可以增加硅灰石的矿化效率;硅灰石的加入,对CO与超临界水反应也有一定的促进作用.在4MPa CO初压,420℃和10g硅灰石样品的条件下,产物气体中H2体积分数最高,为12.2%;在6MPa CO初压,400℃和10g硅灰石样品的条件下得到29.9%的矿石最高矿化效率.

Mineral carbonation, i. e. , carbonation of alkaline silicate Ca/Mg minerals, analogous to natural weathering processes, was a possible technology for reduction of CO2 emissions to the atmos- phere. Alkaline silicate Ca-rich minerals, wollastonite, was used as a feedstock for CO2 mineral carbonation sequestration in the CO-supercritical water system. A series of experiments were carried out to investigate the effects of temperature, CO initial pressure and addition of wollastonite. The experi- mental results show that wollastonite can react with CO2 generated during the reaction, to form a sta- ble carbonate in CO-supercritical water system. Increasing of reaction temperature and CO initial pressure can accelerate the reaction of CO-supercritical water, and the conversion of wollastonite can also be improved accordingly. In this study, a H2 volume content of 12.2% was obtained under the condition of 4 MPa CO initial pressure, 420 ℃ and 10 g wollastonite. And a highest carbonation conversion of 29.9% was obtained under the condition of 6 MPa CO initial pressure, 400 ℃ and 10 g wollastonite in the CO-supercritical water system.