CO2 gasification of Fuijian high-metamorphous anthracite with black liquor (BL) and/or mixture of BL and calcium stuff (BL+Ca) as catalyst was studied by using a thermogravimetry under 750-950℃ at ambient pressu...CO2 gasification of Fuijian high-metamorphous anthracite with black liquor (BL) and/or mixture of BL and calcium stuff (BL+Ca) as catalyst was studied by using a thermogravimetry under 750-950℃ at ambient pressure. When the coal was impregnated with an appropriate quantity of Ca and BL mixture, the catalytic activity of CO2 gasification was enhanced obviously. With a loading of 8%Na-BL+2%Ca, the carbon conversion of three coal samples tested reaches up to 92.9%-99.3% at 950℃ within 30min. The continuous formation of alkali surface compounds such as ([-COM], [-CO2M]) and the presence of exchanged Ca, such as calcium phenolate and calcium carboxylates (COO)2Ca, contribute to the increase in catalytic efficiency, and using BL+Ca is more efficient than that adding BL only, The homogeneous model and shrinking-core model were applied to correlate the data of conversion with time and to estimate the reaction rate constants under different temperature. The corresponding reaction activation energy (Ea) and pre-exponential factor of three anthracites were estimated. It is found that Ea is in the range from 73.6 to 121.4kJ·mol^-1 in the case of BL+Ca, and 74.3 to 104.2kJ·mol^-1 when only BL was used as the catalyst, both of which are much less than that from 143.5 to 181.4kJ·mol^-1 if no catalyst used. It is clearly demonstrated that both of BL+Ca mixture and BL could be the source of cheap and effective catalyst for coal gasification.展开更多
基金Supported by the National Natural Science Foundation of China (No.20376014) and Fujian Science and Technology Council Grant (HG99-01).
文摘CO2 gasification of Fuijian high-metamorphous anthracite with black liquor (BL) and/or mixture of BL and calcium stuff (BL+Ca) as catalyst was studied by using a thermogravimetry under 750-950℃ at ambient pressure. When the coal was impregnated with an appropriate quantity of Ca and BL mixture, the catalytic activity of CO2 gasification was enhanced obviously. With a loading of 8%Na-BL+2%Ca, the carbon conversion of three coal samples tested reaches up to 92.9%-99.3% at 950℃ within 30min. The continuous formation of alkali surface compounds such as ([-COM], [-CO2M]) and the presence of exchanged Ca, such as calcium phenolate and calcium carboxylates (COO)2Ca, contribute to the increase in catalytic efficiency, and using BL+Ca is more efficient than that adding BL only, The homogeneous model and shrinking-core model were applied to correlate the data of conversion with time and to estimate the reaction rate constants under different temperature. The corresponding reaction activation energy (Ea) and pre-exponential factor of three anthracites were estimated. It is found that Ea is in the range from 73.6 to 121.4kJ·mol^-1 in the case of BL+Ca, and 74.3 to 104.2kJ·mol^-1 when only BL was used as the catalyst, both of which are much less than that from 143.5 to 181.4kJ·mol^-1 if no catalyst used. It is clearly demonstrated that both of BL+Ca mixture and BL could be the source of cheap and effective catalyst for coal gasification.