CX-TiO_(2)-La(x)的制备及其可见光下“富集-降解”增溶废水性能  

Preparation of CX-TiO_(2)-La(x) and “enrichment-degradation” degradation of solubilized wastewater under visible light photocatalysis

作　　者：杨春蕾 陆晓慧 刘新杰 琚成功 王爱静 彭啸 吴燕 YANG Chunlei;LU Xiaohui;LIU Xinjie;JU Chenggong;WANG Aijing;PENG Xiao;WU Yan(College of Chemical Engineering and Materials Science,Tianjin University of Science&Technology,Tianjin 300457,China;Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-Utilization,Tianjin 300457,China)

机构地区：[1]天津科技大学化工与材料学院,天津300457 [2]天津市卤水化工与资源生态化利用重点实验室,天津300457

出　　处：《精细化工》2022年第6期1234-1241,共8页Fine Chemicals

基　　金：国家自然科学基金(21806122)。

摘　　要：以间苯二酚、间苯三酚、甲醛、氯化镧、TiO_(2)纳米粒子为原料,草酸为催化剂,制备湿凝胶,再经恒温干化、N_(2)高温煅烧制备了一系列光催化复合材料CX-TiO_(2)-La(x)(x为La掺杂量的100倍,La掺杂量以TiO_(2)、甲醛、间苯二酚和间苯三酚的总物质的量为基准,取值为0.05、0.5和8),将其用于可见光下处理模拟土壤淋洗废水(即曲拉通100增溶的菲)。通过XRD、SEM、N_(2)吸附-脱附、FTIR对其进行了表征。结果表明,该复合材料的晶体组成主要为无定形碳、金红石型TiO_(2)和La_(2)Ti_(2)O_(7)。CX-TiO_(2)-La(0.5)的比表面积为549.35 m^(2)/g,暗态吸附30 min,500 W氙灯照射5 h下,其对曲拉通100(质量浓度为5 g/L)增溶的菲(质量浓度为100 mg/L)的移除率为83.6%。复合材料增溶菲的吸附过程符合准二级动力学模型和Langmuir模型,且为自发的化学吸附过程。推测材料内部形成了La_(2)Ti_(2)O_(7)-CX-TiO_(2)异质结结构扩大了TiO_(2)的光催化响应范围,使其在可见光下获得高的光催化降解效率,经8次循环使用后,CX-TiO_(2)-La(0.5)仍对增溶菲有较高的移除率。A series of composites CX-TiO_(2)-La(x)(x is 100 times La doping amount,and the La doping amount is based on the total substance amount of TiO_(2),formaldehyde,resorcinol and phloroglucinol,the values are 0.05,0.5 and 8) were prepared from solid solution gel,an intermediate formed by resorcinol,phloroglucinol,formaldehyde,lanthanum chloride and TiO_(2)nanoparticles using oxalic acid as catalyst,through constant temperature drying and high temperature calcination in N_(2)atmosphere.Characterization by XRD,SEM,N_(2)adsorption-desorption and FTIR showed that the composites were mainly composed of amorphous carbon,rutile TiO_(2)and La_(2)Ti_(2)O_(7).Analysis by N_(2)adsorption-desorption indicated that the specific surface area of CX-TiO_(2)-La(0.5) reached 549.35 m^(2)/g.When used to treat simulated soil leaching(solubilization) wastewater,which is 100 mg/L (mass concentration) phenanthrene by solubilized with Triteron 100 (5 g/L),under visible light,CX-TiO_(2)-La(0.5) demonstrated a removal rate of 83.6%.Kinetic model analyses proved that the adsorption process of phenanthrene was basically a spontaneous chemical adsorption process and in accordance with the second-order kinetic model and Langmuir model.It was speculated that the La_(2)Ti_(2)O_(7)-CX-TiO_(2)heterojunction structure was formed,which expanded the correspondingly photocatalytic range of TiO_(2)and made it obtain high photocatalytic degradation efficiency under visible light.After 8 cycles of use,CX-TiO_(2)-La(0.5) still maintained a high removal rate of solubilized phenanthrene.

关 键 词：钛酸镧 碳干凝胶 二氧化钛 多环芳烃 表面活性剂 催化 降解 水处理技术 

分 类 号：O643[理学—物理化学]