基于撞击流微反应器连续制备纳米ZnO及其光催化性能研究

以Zn（NO3）2、Na2CO3为原材料,采用自制撞击流微反应器连续制备出纳米ZnO,系统研究了反应温度、反应物浓度、进料速率等工艺条件对所制备纳米ZnO光催化性能的影响,采用SEM、XRD等测试手段对制备产物的物相及微观形貌进行了表征.结果表明,采用撞击流微器可实现纳米ZnO的连续高效制备,其光催化性能随着反应温度和进料速率的增大而升高,随着反应物浓度的增大先提高后降低.当反应温度为80℃,反应物浓度为0.3 mol·L-1,Na2 CO3溶液的进料速率为350 mL·min-1、Zn（NO3）2溶液的进料速率为291 mL· min-1时,可制得平均粒径为20.1 nm,粒径分布较均匀的纳米ZnO.以其为光催化剂,在100 W高压汞灯照射下降解甲基橙（MO） 40 min,其降解率可达到93.9％,表现出良好的光催化性能.

Continuous Preparation and Photocatalytic Property of ZnO Nanomaterials Based on Impinging Stream Microreactor

A self-made impinging stream microreactor were successfully adopted to pre- pare ZnO nanomaterial with Zn（NO3）2, Na2CO3 as raw materials. The influence of re- action temperature, flow rate and reactant concentration on the photocatalytic activity of the ZnO nanomaterial was investigated, and the microstructure and morphology of ZnO nanomaterial were characterized by X-ray diffraction （XRD） and scanning electron mi- croscopy （SEM）. The results indicated that the highly efficient continuous production of ZnO nanomaterial can be achieved using the impinging stream microreactor. The pho- tocatalytic activity of ZnO nanomaterial increased with increasing reaction temperature, flow rate, but initially increased and subsequently decreased with increasing reactant concentration. Uniform ZnO nanoparticles with average size of about 20.1 nm were ob- tained at reaction temperature of 80℃, reactant concentration of 0.2 mol ·L^- 1 , and flow rates of 350 mL · min-1 Na2CO3 and 291 mL · min ^-1 Zn（NO3）2 solution. The ZnO nanomaterial has an excellent photocatalytic activity to degrade methyl orange（MO）,with a degradation efficiency exceeding 93.9% ,under a 100 W mercury lamp for 40 min.