酸/碱/盐改性增强分子筛对苯乙烯的吸脱附性能  

Enhancement of styrene adsorption and desorption performance on zeolite by acid,alkali and salt modification

作　　者：李瑞洁 邓毅强 纪宇飞 罗颖鸿 赵彩悦 叶代启 吴军良 LI Ruijie;DENG Yiqiang;JI Yufei;LUO Yinghong;ZHAO Caiyue;YE Daiqi;WU Junliang(School of Environment and Energy,South China University of Technology,Guangzhou 510006,China;Changxing Electronics(Suzhou)Co.Ltd.,Suzhou 215151,China;National Engineering Laboratory for VOCs Pollution Control Technology and Equipment,Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control,Guangzhou 510006,China)

机构地区：[1]华南理工大学环境与能源学院,广州510006 [2]长兴电子(苏州)有限公司,苏州215151 [3]挥发性有机物污染治理技术与装备国家工程实验室,广东省大气环境与污染控制重点实验室,广州510006

出　　处：《环境工程学报》2024年第7期1891-1900,共10页Chinese Journal of Environmental Engineering

基　　金：广东省自然科学基金资助项目(2023A1515010193);国家重点研发计划资助项目(2022YFB4101500)。

摘　　要：苯乙烯由于易在吸附材料上发生聚合导致采用吸附法处理时难以脱附,如何实现苯乙烯的有效脱附是当前挥发性有机物(VOCs)污染治理领域公认的技术难题。采用一种高硅分子筛作为吸附剂,研究了硝酸、乙酸钠和硫酸钠3种溶液改性对分子筛吸脱附苯乙烯性能的影响。结果表明,改性后的分子筛有效减少了苯乙烯在吸脱附过程中的聚合行为,脱附性能得到明显提升,硫酸钠、乙酸钠、硝酸的最佳改性浓度分别为1、0.05和1 mol·L^(-1)。0.05 mol·L^(-1)CH_(3)COONa改性的样品表现出最优的苯乙烯吸脱附性能,将脱附率由80%提高至90%,吸附量可达122 mg·g^(-1),且经过10次吸脱附循环后仍可维持初始吸附量的85%以上。样品的表征结果表明分子筛的酸性位点会加剧苯乙烯的聚合,硝酸和乙酸钠改性后样品的酸性位点减少、酸性强度降低,因此,苯乙烯的聚合程度降低,脱附性能提高;硫酸钠改性样品酸性位点的减少和孔道限域效应的增强共同促进了脱附性能的提高。Desorption of styrene during adsorption processes is a big challenge due to its tendency to polymerize on adsorbent materials,how to realize the effective desorption of styrene is a well-recognized issue in the field of volatile organic compounds(VOCs)pollution control.In this study,a kind of high silicon zeolite was used to explore the effect of different modifications with nitric acid,sodium acetate,and sodium sulfate on its performance of styrene adsorption and desorption.The results indicated the polymerization behavior of styrene in the process of absorption and desorption on the modified zeolite were effectively reduced and the desorption performance for all samples increased significantly.The optimal concentrations for sodium sulfate,sodium acetate,and nitric acid modifications were 1,0.05 and 1 mol·L^(-1),respectively.The zeolite modified with 0.05 mol·L^(-1)CH_(3)COONa exhibited the best styrene desorption performance with an increase in desorption rate from 80%to 90%,and the absorption capacity could reach 122 mg·g^(-1),and over 85%of its initial adsorption capacity could be maintained even after ten cycles.Characterization of the samples revealed that the acidic sites of zeolites could intensify the polymerization of styrene.Zeolites modified by nitric acid and sodium acetate showed the decrease in acidic strength and reduction of acidic sites,thus,the polymerization of styrene decreased and the desorption performance increased.For zeolites modified by sodium sulfate,both the enhancement of the pore confinement and the reduction in acidic sites promote the desorption of styrene.

关 键 词：苯乙烯 聚合 分子筛 改性 吸脱附 

分 类 号：X703[环境科学与工程—环境工程]