A novel micro kinetic analyzer(MFBK) for fluidized bed gas-solid reactions is developed.With this MFBK analyzer,the reaction rate and kinetic parameters can be deduced via measuring the time-dependent composition chan...A novel micro kinetic analyzer(MFBK) for fluidized bed gas-solid reactions is developed.With this MFBK analyzer,the reaction rate and kinetic parameters can be deduced via measuring the time-dependent composition changes of its evolved gas.By using a micro fluidized bed reactor,it is expected to enable the on-line feed of particle reactant based on a pulse solid conveying mechanics and the effective suppression of external gas diffusion in the reactor.This MFBK analyzer is evaluated through the decomposition of CaCO3 powder,giving an apparent activation energy of 142.73 kJ·mol-1 and a preexponential factor of 399777 s-1.This activation energy value is much lower then the TG-measured one of 184.3 kJ·mol-1 and within the literature-reported range of 120—280 kJ·mol-1.The measurement also provides a kinetic-model function with a correlation linearity of above 0.99.With this MFBK analyzer,the pyrolysis of coal and biomass at 800℃ is studied.The measured pyrolysis reaction finished in about 15 s,which is very close to the theoretically anticipation.This pyrolysis measurement with the MFBK analyzer can also identify a definite gas release order for typical gas species contained in the pyrolysis-formed gas products,which actually can provide a strong evidence for the deep insight in the pyrolysis reaction mechanism.展开更多
采用脉冲电催化内电解流化床技术同时去除浮选废水中的Pb2+和苯胺黑药,运用序批试验和SEM、XPS等分析研究影响污染物去除的工艺条件、脉冲电催化效应、Pb2+和苯胺黑药的去除或降解机制。结果表明:当p H为4、电流密度为20 m A/cm2、脉冲...采用脉冲电催化内电解流化床技术同时去除浮选废水中的Pb2+和苯胺黑药,运用序批试验和SEM、XPS等分析研究影响污染物去除的工艺条件、脉冲电催化效应、Pb2+和苯胺黑药的去除或降解机制。结果表明:当p H为4、电流密度为20 m A/cm2、脉冲周期为2 s、停留时间为90 min时,Pb2+和苯胺黑药的去除率分别为99.80%和78.83%,BOD5/CODCr值由0.15上升至0.41。该技术能较好地同时去除浮选废水中的Pb2+和苯胺黑药,显著提高废水的可生化性。Pb2+和苯胺黑药的去除得益于脉冲电催化内电解体系下的氧化还原反应、电沉积和高聚合度铁氢氧化物的絮凝沉淀作用等;苯胺黑药在新生态Fe2+、[H]、H2O2、·OH等活性物质的作用下先后脱除二硫代磷酸基、脱氨基、苯环开环断裂而被降解为有机小分子和无机物。展开更多
文摘A novel micro kinetic analyzer(MFBK) for fluidized bed gas-solid reactions is developed.With this MFBK analyzer,the reaction rate and kinetic parameters can be deduced via measuring the time-dependent composition changes of its evolved gas.By using a micro fluidized bed reactor,it is expected to enable the on-line feed of particle reactant based on a pulse solid conveying mechanics and the effective suppression of external gas diffusion in the reactor.This MFBK analyzer is evaluated through the decomposition of CaCO3 powder,giving an apparent activation energy of 142.73 kJ·mol-1 and a preexponential factor of 399777 s-1.This activation energy value is much lower then the TG-measured one of 184.3 kJ·mol-1 and within the literature-reported range of 120—280 kJ·mol-1.The measurement also provides a kinetic-model function with a correlation linearity of above 0.99.With this MFBK analyzer,the pyrolysis of coal and biomass at 800℃ is studied.The measured pyrolysis reaction finished in about 15 s,which is very close to the theoretically anticipation.This pyrolysis measurement with the MFBK analyzer can also identify a definite gas release order for typical gas species contained in the pyrolysis-formed gas products,which actually can provide a strong evidence for the deep insight in the pyrolysis reaction mechanism.
