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991.
光催化活性纳米TiO_2溶胶的低温制备及其表征 总被引:1,自引:0,他引:1
以TiCl4为原料,低于100℃条件下制备了锐钛矿型纳米TiO2溶胶。通过XRD测试和对甲基橙和亚甲基兰的光催化降解试验,考察了TiO2溶胶制备过程中各因素对TiO2内部结构和性能的影响,进而选出最佳的制备条件。通过光催化降解品红试验和对馒头片的抗菌试验检验了此条件下制备的TiO2溶胶具有良好的光催化活性。 相似文献
992.
Ferrate is an excellent water treatment agent for its multi-functions in oxidation, disinfection, coagulation and adsorption, but its coagulation ability depends on its dosage and is after its oxidation. This paper focuses on preparing a new kind of ferrate combined with alum to enhance its coagulation function for water purification. An effective electrolysis reactor was designed and employed in the test. Some key parameters in the process of electrolysis concerning the preparation efficiency, such as the current density, temperature and alkalinity were also investigated. The proper conditions for ferrate-alum preparation were determined. In the condition of 5V given voltage, 6h electrolyzing interval, below 2% alum concentration (in weight), a combined liquid ferrate-alum products was successfully prepared, which contained 0.0294 mol/L FeO4/sub>2-, 0.0302 mol/L total soluble ferron with 2% Al2O3. There was no insoluble ferron produced by controlling an optimum electrochemical condition. 相似文献
993.
通过静态吸附试验,考究了Cd^2+在FCC废催化剂上的吸附热力学动力学。结果表明,吸附规律可用Langmuir和Freundlich等温吸附模式很好地描述,吸际呈单分子层形式,且吸附容易进行,吸附为吸热过程,以化学吸附和离子交换吸附为主,吸附动力学过程符合Bangham吸附速率模式,颗粒内扩散过程为吸附速度控制步骤。又做了动态吸附试验,结果表明,在本试验条件下Cd^2+的动态吸附及脱附动力学特性良 相似文献
994.
Chorionic villi from 20 diagnostic cases were prepared for cytogenetic analysis by a direct and two short-term culture methods. No significant differences were found between the methods in the quality and quantity of metaphases obtained. A further study using villi from 20 pre-termination patients indicated an inherent variation in the quality of villi resulting in inconsistent processing and variation in the response of a sample to the methods. This suggests that it would be advantageous to process the villi by more than one method. 相似文献
995.
通过在3组日处理规模为5m^3/d的活性污泥法装置中进行连续进出水试验,考察了投加多功能复合微生物制剂(multifunctional compound micro—organisms preparation,MCMP)对污水处理过程中剩余污泥减量的影响。中试研究结果表明,曝气池中,每次MCMP菌剂加入量为日处理水量的0.02%~0.04%的条件下,运行2个月装置未排放剩余污泥,有效地实现剩余污泥源头减量的预期要求。该技术不增加或改变原有污水处理工艺和运行方式,不增加处理系统总的动力消耗,并且不会对出水水质产生不良影响。 相似文献
996.
997.
无银催化-微波消解快速测定污水中化学需氧量研究 总被引:17,自引:0,他引:17
以MgSO4 CuSO4 为催化剂 ,探讨了无银催化微波消解测定污水中化学需氧量的方法。通过对影响污水消解效率的系列条件试验 ,确定了微波消解测定污水CODCr的最佳条件 :微波功率为中强火、消解时间为 5min、混酸介质H3PO4 H2 SO4 配比为 1∶4、消解酸度为 5 0 %、催化剂MgSO4 CuSO4 配比为 1∶1等。用该方法测定污水中的CODCr,与回流法测得结果吻合。该方法采用无银催化剂和微波消解 ,具有精密度高、操作费用低、消解速度快等特点 相似文献
998.
999.
Synergistic removal of nitrogen monoxide using non-thermal plasma and catalyst simultaneously 总被引:2,自引:0,他引:2
An experimental system of De-NO with plasma-catalyst(Cu zeolite) was established to investigate the differences between De- NO with plasma-catalyst and De-NO only with plasma, to provide the instruction for selecting appropriate catalyst and operating condition, The characteristics of De-NO with plasma and De-NO with plasma-catalyst were investigated comparatively by experiments. The experimental results show that De-NO with plasma-catalyst has high NO removal rate; Cu zeolite is an effective catalyst which can promote NO removal rate in plasma remarkably; De-NO with plasma-catalyst should be operated at low temperature and the temperature has opposite effects on the function of catalvst and plasma; water vapor and O2 can increase the NO removal rate. 相似文献
1000.
The low-heat-value cornstalk gas produced in the down-flow fixed bed gasifier was tentatively used for methanol synthesis. The cornstalk gas was purified and the technical procedures such as deoxygenation, desulfurization, catalytic cracking of tar, purification and hydrogenation were studied. The catalytic experiments of methanol synthesis with cornstalk syngas were carried out in a tubular-flow integral and isothermal reactor. The effect of reaction temperature, pressure, catalysttypes, catalyst particle size, syngas flow at entering end and composition of syngas was investigated. The optimum process conditions and yield of methanol from cornstalk syngas were obtained. The experimental results indicated that the proper catalyst of the synthetic reaction was C301 and the optimum catalyst size (φ) was 0.833 mm×0.351 mm. The optimum operating temperature and pressure were found to be 235℃ and 5 Mpa, respectively. The suitable syngas flow 0.9-1.10 mol/h at entering end was selected and the best composition of syngas were CO 10.49%, CO2 8.8%, N2 37.32%, CnHm 0.95% and H2 40.49%. The best methanol yield is 0.418 g/g cornstalk. The study provided the technical support for the industrial test of methanol production from biomass (cornstalk)gas. 相似文献