为了解直流正电晕-纳米银沉积纳米TiO2光电催化耦合反应系统降解乙烯及调控臭氧的机理及其动力学规律，该文采用多针对圆筒内壁式电晕放电反应器为对象，在模拟园艺产品的冷藏环境中，进行了纳米TiO2的掺银量、放电功率和气流量等因素对乙烯降解和臭氧控制效果的影响研究。结果表明：建立了正电晕放电耦合活性炭纤维（activated carbon fiber，ACF）负载掺银的纳米TiO2（Ag-TiO2/ACF、Ag-TiO2*/ACF）降解乙烯的动力学模型，通过龙格库塔法数值求解微分方程组和最小二乘法得到动力学模型的反应常数，通过对反应常数比较，正电晕放电耦合 Ag-TiO2*/ACF 催化膜对乙烯降解和控制臭氧浓度具有较优的性能。采用二次旋转组合试验和回归拟合，建立了正电晕放电耦合 Ag-TiO2*/ACF 催化膜的乙烯降解反应常数、臭氧浓度上限的预测值与影响因素关系的二次多项数学模型，验证了模型的有效性，并优化出反应体系参数。研究结果为正直流电晕放电耦合纳米二氧化钛技术在园艺产品贮运保鲜设备中的应用提供了依据。%The quality of horticultural products in cold-storage environment rapidly declines due to its perishability. Ethylene is one of important factors to facilitate the perishing process, because it enhances the respiration intensity and enzymatic activities of horticultural products. We introduce the non-thermal plasma which were produced by positive corona into the horticultural cold-storage, it can remove the volatile organic gases effectively, safely, and stably. However, the corona generates much ozone that may poison fruits and vegetables. A more effectual method to use the non-thermal plasma is coupling it with heterogeneous catalysis technology. To explore the mechanism and kinetics of ethylene degradation and ozone regulation in the photoelectric catalyzed coupling reaction system of direct current positive corona-elemental silver deposit nanometer TiO2. In this paper, the cylinder wall was used as corona discharge reactor, with needle-array-versus- inner-cylinder-wall corona electrode, and with nano-TiO2 as catalysis deposited with nanometer silver. The impacts of silver doping amount, discharge power and gas flow rate and other factors on ethylene degradation and ozone control effect were carried out in the simulation of the horticultural products cold storage environment, verified the intrinsic kinetics of the reaction process by surveying the changes of concentration of ethylene as well as ozone. The results showed that ethylene degradation dynamics model of positive corona discharge coupling activated carbon fiber (ACF) supported Ag doped nano-TiO2 (Ag-TiO2/ACF) was established. Corona discharge coupling Ag-TiO2*/ACF catalytic membrane on degradation of ethylene and control of the ozone concentration has a superior performance by comparing the reaction constant of Runge Kutta method for solving differential equations and least square method for dynamics model. By means of quadratic rotary combination experiment and regression fitting, quadratic multinomial model of reaction constant of corona discharge coupling Ag-TiO2*/ACF catalytic membrane on the degradation of ethylene and the limits of predicted values of ozone concentration was established. The validity of the model was verified, and parameters of reaction system were optimized at the same time. The optimal conditions for storage of apple was that silver doping amount of 0.5%, discharge power of 0.47 W and gas flow rate of 400 L/h. The research can provide a reference for the technology of direct current positive corona discharge coupling nano-TiO2 in the application of storage and transportation equipment of horticultural products.
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