The mathematical model for the thermokinetics of irreversible consecutive first order reactions has been suggested,which was used for the calculation of rate constants and molar enthalpies of the two consecutive steps...The mathematical model for the thermokinetics of irreversible consecutive first order reactions has been suggested,which was used for the calculation of rate constants and molar enthalpies of the two consecutive steps.And its validity has been verified by the ex- perimental results.展开更多
In this account,highly ordered mesoporous MnO_x/TiO_2composite catalysts with efficient catalytic ozonation of phenol degradation were synthesized by the sol–gel method.The surface morphology and properties of the ca...In this account,highly ordered mesoporous MnO_x/TiO_2composite catalysts with efficient catalytic ozonation of phenol degradation were synthesized by the sol–gel method.The surface morphology and properties of the catalysts were characterized by several analytical methods,including SEM,TEM,BET,XRD,FTIR,and XPS.Interestingly,Mn doping was found to improve the degree of order,and the ordered mesoporous structure was optimized at 3%doping.Meanwhile,MnO_xwas highly dispersed in the ordered mesoporous materials to yield good catalytic ozonation performance.Phenol could completely be degraded in 20 min and mineralized at 79%in 60 min.Thus,the catalyst greatly improved the efficiency of degradation and mineralization of phenol when compared to single O_3or O_3+TiO_2.Finally,the reaction mechanism of the catalyst was discussed and found to conform to pseudo-first-order reaction dynamics.展开更多
Two methods of computer data processing, linear fitting and nonlinear fitting, are applied to compute the rate constant for hydrogen peroxide decomposition reaction. The results indicate that not only the new methods ...Two methods of computer data processing, linear fitting and nonlinear fitting, are applied to compute the rate constant for hydrogen peroxide decomposition reaction. The results indicate that not only the new methods work with no necessity to measure the final oxygen volume, but also the fitting errors decrease evidently.展开更多
The kinetics of the first order autocatalytic decomposition reaction of nitrocellulose (NC, 13.86% N) was stud-ied by using DSC. The results show that the DSC curve for the initial 50% of conversion degree of NC can b...The kinetics of the first order autocatalytic decomposition reaction of nitrocellulose (NC, 13.86% N) was stud-ied by using DSC. The results show that the DSC curve for the initial 50% of conversion degree of NC can be de-scribed by the first order autocatalytic equation dy/dt=-10^(16.3)exp(-181860/RT)y-10^(16.7)exp(-173050/RT)y(1-y) and that for the latter 50% conversiondegree of NC described by the reaction equations dy/dt=-10^(16.4)exp(-154820/RT)y(n=1) and dy/dt=-10^(16.9)exp(-155270/RT)y^(2.80)(n≠1).展开更多
文摘The mathematical model for the thermokinetics of irreversible consecutive first order reactions has been suggested,which was used for the calculation of rate constants and molar enthalpies of the two consecutive steps.And its validity has been verified by the ex- perimental results.
基金Supported by the National Natural Science Foundation of China(21676139)the Higher Education Natural Science Foundation of Jiangsu Province(15KJA530001)+1 种基金Research Fund of State Key Laboratory of Materials-Oriented Chemical Engineering(ZK201604)the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘In this account,highly ordered mesoporous MnO_x/TiO_2composite catalysts with efficient catalytic ozonation of phenol degradation were synthesized by the sol–gel method.The surface morphology and properties of the catalysts were characterized by several analytical methods,including SEM,TEM,BET,XRD,FTIR,and XPS.Interestingly,Mn doping was found to improve the degree of order,and the ordered mesoporous structure was optimized at 3%doping.Meanwhile,MnO_xwas highly dispersed in the ordered mesoporous materials to yield good catalytic ozonation performance.Phenol could completely be degraded in 20 min and mineralized at 79%in 60 min.Thus,the catalyst greatly improved the efficiency of degradation and mineralization of phenol when compared to single O_3or O_3+TiO_2.Finally,the reaction mechanism of the catalyst was discussed and found to conform to pseudo-first-order reaction dynamics.
文摘Two methods of computer data processing, linear fitting and nonlinear fitting, are applied to compute the rate constant for hydrogen peroxide decomposition reaction. The results indicate that not only the new methods work with no necessity to measure the final oxygen volume, but also the fitting errors decrease evidently.
基金the Science and Technology Foundation of Shaanxi Key Laboratory of Physico-Inorganic Chemistry (No. 29-3, 2001), and the Science and Technology Foundation (No. 514550101) of Propellant and Explosive Combustion of China.
文摘The kinetics of the first order autocatalytic decomposition reaction of nitrocellulose (NC, 13.86% N) was stud-ied by using DSC. The results show that the DSC curve for the initial 50% of conversion degree of NC can be de-scribed by the first order autocatalytic equation dy/dt=-10^(16.3)exp(-181860/RT)y-10^(16.7)exp(-173050/RT)y(1-y) and that for the latter 50% conversiondegree of NC described by the reaction equations dy/dt=-10^(16.4)exp(-154820/RT)y(n=1) and dy/dt=-10^(16.9)exp(-155270/RT)y^(2.80)(n≠1).
