吸附VOCs用陶瓷基蜂窝块体吸附剂研究

发布时间：2018-06-19 06:53

本文选题：VOCs + 分子筛　；参考：《华南理工大学》2015年硕士论文

【摘要】：挥发性有机化合物(VOCs)对大气环境造成破坏,也给人类健康带来威胁。以分子筛为吸附剂,对大风量、低浓度有机废气的去除,吸附式蜂窝转轮系统,具有高效、连续、节能等特点,在工业处理尾气中被广泛使用。该系统的核心是转轮吸附材料(块体吸附剂,Monolithic Adsorbent),它是决定系统净化有机废气能力的关键因素。为此,本论文就去除VOCs块体吸附剂的制备工艺及产品性能进行了深入探讨。首先,开展了陶瓷基瓦楞纸片及块体、陶瓷基分子筛瓦楞纸片的制备研究。探讨了不同润湿剂(SDS,OP-10以及co-436)对陶瓷瓦楞纸片润湿性能的影响;考察了不同干燥方式(热风、微波)下硅溶胶在蜂窝块体中的分布;分析了不同分子筛质量分数下陶瓷瓦楞纸片的挂胶量。实验发现,润湿剂对硅溶胶在陶瓷瓦楞纸片上的润湿效果有明显的改善,并以非离子表面活性剂烷基酚聚氧乙烯醚(OP-10)最为显著。与空白相比,其完全润湿时间由超过24h变成6.73s,改性液接触角由35.45°降至23.08°;SEM图显示,微波干燥较于普通热风干燥,硅溶胶在基材上分布更均匀;随着分子筛质量分数的提高,纸张挂胶量上升,当分子筛质量分数为23.08%,挂胶量变缓,提高至33.33%时,出现掉粉和堵孔现象。其次,经初选,以国产分子筛(Domestic molecular sieve,记DM)、2种进口分子筛(Imported molecular sieve,记IMa、IMb)制作的陶瓷基瓦楞吸附纸片为吸附剂,以典型的极性溶剂二氯甲烷(CH2Cl2)和非极性溶剂苯(C6H6)为吸附质。采用动态吸附法,考察了温度、吸附质浓度及进口风量对分子筛吸附纸片吸附性能的影响。结果显示:吸附纸片对VOCs有明显的吸附效果,并以IMa的吸附性能最好,尤其是对苯的吸附。当以CH2Cl2作吸附质时,温度和浓度对IMa吸附纸片的影响最为明显,而风量对IMb的影响较大。随着分子筛质量分数的增加,吸附纸片对苯、二氯甲烷穿透时间、吸附量均逐渐增加;而IMa纸片对CH2Cl2的穿透时间、吸附量的降低,可能与其孔容大、易堵塞孔道使传质受阻,以及IMa吸附热较大,热量难以散失有关联。最后,以甲苯(C7H8)作吸附质,开展了DM陶瓷蜂窝块体吸附剂吸附性能的初步研究,结果显示出良好的吸附穿透时间(80min)和吸附容量(1.332×10-2 g?g-1)。
[Abstract]:Volatile organic compounds (VOCs) damage the atmospheric environment and threaten human health. With molecular sieve as adsorbent, the removal of large air volume, low concentration of organic waste gas and adsorption honeycomb runner system are widely used in industrial treatment of tail gas because of their characteristics of high efficiency, continuity and energy saving. The core of the system is the adsorption material (bulk adsorbent monolithic sorbentine), which is the key factor to determine the ability of the system to purify organic waste gas. Therefore, the preparation process and product properties of bulk adsorbents for VOCs removal were discussed in this paper. Firstly, the preparation of ceramic corrugated sheet and bulk, ceramic base molecular sieve corrugated sheet were studied. The effects of different wetting agents (SDS- OP-10 and co-436) on the wettability of corrugated ceramic corrugated sheets were investigated, and the distribution of silica sol in honeycomb blocks under different drying methods (hot air, microwave) was investigated. The adhesive content of corrugated ceramic sheets with different molecular sieve mass fraction was analyzed. It was found that wetting agent could improve the wetting effect of silica sol on ceramic corrugated board obviously, and the Nonionic surfactant alkylphenol polyoxyethylene ether (OP-10) was the most obvious. Compared with the blank, the complete wetting time changed from more than 24 hours to 6.73 s, and the contact angle of the modified solution decreased from 35.45 掳to 23.08 掳SEM. When the weight fraction of molecular sieve was 23.08, the amount of glue hanging increased to 33.33, and the phenomenon of powder dropping and pore plugging appeared when the weight fraction of molecular sieve was 23.08. Secondly, the ceramic corrugated adsorbed paper made from domestic molecular sieve, imported molecular sieveand Ima-imb) was used as adsorbent, the typical polar solvent methylene dichloride (Ch _ 2Cl _ 2) and the non-polar solvent benzene C _ 6H _ 6) as adsorbents. The effects of temperature, concentration of adsorbents and air volume on the adsorption properties of molecular sieve were investigated by dynamic adsorption method. The results showed that the adsorption of VOCs on the disk was obvious, and the adsorption performance of IMA was the best, especially the adsorption of benzene. When Ch _ 2Cl _ 2 was used as adsorbent, the temperature and concentration had the most obvious effect on the adsorption of IMA, but the influence of air volume on IMB was more obvious. With the increase of molecular sieve mass fraction, the penetration time of adsorbed disk to benzene and dichloromethane increased gradually, while the penetration time of IMa disk to Ch _ 2Cl _ 2 and the decrease of adsorption capacity may be related to the large pore volume and the blocking of pore channel to block mass transfer. And the adsorption heat of IMA is larger and the heat is difficult to dissipate. Finally, the adsorption properties of DM ceramic honeycomb bulk adsorbents were studied with toluene C _ 7H _ 8 as adsorbent. The results showed that the adsorption penetration time was 80 min) and the adsorption capacity was 1.332 脳 10 ~ (-2) g 路g ~ (-1) 路m ~ (-1).
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ424;X701

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