粉煤灰有效成分提取与电石渣掺杂制备碳吸附剂及性能研究OA

Industrial calcium carbide slag has advantages such as low cost and good CO2 adsorption performance.However,it tends to sinter after multiple cycles at high temperatures,directly resulting in low CO2 adsorption capacity.Enhancing the activity and specific surface area of calcium carbide slag to improve its CO2 adsorption-desorption performance has become an urgent challenge.Amorphous aluminum hydroxide was extracted from fly ash by mixed calcination of fly ash,Na2CO3,and CaCO3,and then incorporated into carbide slag to prepare aluminum-calcium-based composite adsorbents.Four samples with different doping ratios of the modified adsorbents were prepared and tested for adsorption performance and cyclic stability under various adsorption temperatures.The results showed that during the rapid reaction phase,the CA91(mCa(OH)∶mAlO(OH)=9∶1)and CA73(mCa(OH)2∶mAlO(OH)=7∶3)samples exhibited the fastest adsorption reaction rates.2 After the adsorption reaction was completed,the adsorption capacities of four doping ratios followed the order:CA73>CA91>CA82(mCa(OH)∶mAlO(OH)=8∶2)>CA64(mCa(OH)2∶mAlO(OH)=6∶4).In terms of cyclic performance,pure carbide slag2 showed a significant decrease in stability after 13 cycles,with its adsorption capacity reduced by 15%.In contrast,CA73 exhibited only a 5%decrease in adsorption capacity after 20 cycles,making it the optimal adsorbent.Further adsorption-desorption experiments on CA73 at constant and varying temperatures identified the optimal adsorption temperature as 750℃.The local disposal and resource utilization of carbide slag and fly ash are achieved,and a cost-effective adsorbent for CO2 emission reduction is also provided.