活性炭负载铈催化臭氧处理桉木制浆废水

Catalytic Ozonation of Eucalyptus Pulping Effluent by Cerium Loaded on Activated Carbon

关键词:  制浆废水  臭氧  催化  活性炭  铈

Key Words:pulping effluent  ozone  catalysis  activated carbon  cerium

摘要:通过浸渍法在活性炭（AC)上负载铈（Ce）制备了催化剂(Ce-AC),并用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和比表面积分析仪(BET)对制备的催化剂进行表征,研究了该催化剂催化臭氧处理桉木制浆废水对COD_Cr和色度的去除效果。结果表明,Ce以CeO₂晶型的形式负载在AC上；Ce负载量为1.0%时,Ce-AC催化臭氧处理桉木制浆废水效果最好;当反应30 min时,废水的色度和COD_Cr去除率达到95%和55%,分别比单独臭氧氧化过程提高10个和18个百分点,比AC催化臭氧氧化过程提高5个和12个百分点;Ce-AC催化臭氧处理桉木制浆废水极大地提高了对废水COD_Cr的去除率。动力学分析表明,单独臭氧氧化及AC、Ce-AC催化臭氧处理制浆废水的过程中,COD_Cr降解的反应符合表观二级动力学方程,负载的Ce提高了反应的动力学速率常数。

Abstract:In this work, Ce-loaded activated carbon (Ce-AC) was prepared and used as catalyst to promote COD and color removal rates of eucalyptus pulping effluent by ozone. The prepared Ce-AC was characterized by XRD, SEM and BET. Results indicated that cerium of Ce-AC existed in the form of CeO2. The best catalytic ozonation effect was found when cerium loading content was 1.0%, color and COD_Cr removal rates were up to 95% and 55% respectively when reaction time 30 minutes, compared with ozonation treatment alone, color and COD_Cr removal rates increased by 10 and 18 percentage points respectively using 1.0% Ce-AC catalytic ozonation; under the same reaction conditions; compared with using AC, using 1.0% Ce-AC as catalyst color and COD_Cr removal rates increased by 5 and 12 percentage points respectively. The COD_Cr removal rate of eucalyptus pulping effluent was greatly increased by Ce-AC catalytic ozonation. Kinetics analyses showed that COD_Crdegradation followed apparent second-order kinetic equation, and Ce loading on AC increased the reaction rate constant.