【作者】 马慧；

【导师】 张永春；

【作者基本信息】 大连理工大学 ， 工业催化， 2011， 硕士

【摘要】 羰基硫(又称氧硫化碳或羰酰硫,Carbonyl Sulfide, COS)是一种无色的有机酸性气体,分子是直线型结构,酸性和极性均弱于H2S。COS广泛存在于天然气、液化石油气、焦炉气、水煤气和半水煤气等工业气体中,由于原料和工艺的不同,含量也不相同。它普遍存在的浓度都很低,但在实际的工业过程中却很难脱除,而且对它的脱除净化率也很有限,要降低工业废气和食品级C02中的总硫含量,脱除低浓度COS,是实现精脱硫的关键。所以本论文的任务是寻找一种吸附剂脱除低浓度的羰基硫。本论文主要的研究工作从四个方面展开,主要内容如下：1.碱改性活性炭纤维(ACF)脱除低浓度COS的研究研究了NaOH、KOH、Na2CO3、K2CO3浸渍改性活性炭纤维脱除COS的性能。考察了改性离子的种类、含量、吸附温度和CO2气氛对ACF脱硫性能的影响。结果表明：ACF在碱改性后,硫容量有很大的提高；其中15%KOH比其他碱改性有更高的硫容量,最佳吸附温度为40℃,原料气中有CO2存在时,吸附剂的脱硫性能下降。2.聚乙烯亚胺(PEI)改性SBA-15脱除低浓度COS的研究研究了PEI改性SBA-15脱除COS的性能。考察了PEI含量、吸附温度、吸附剂颗粒大小和原料气的伴生组分CO2对脱硫性能的影响。结果表明：PEI的负载量为50%时,脱除COS效果最好；最佳吸附温度为60℃；吸附剂颗粒为60-80目时脱硫效果最佳。原料气中有CO2时,存在竞争吸附,吸附剂对COS的吸附效果大大降低,吸附过程中包含了物理吸附和化学吸附。推测了PEI/SBA-15脱除COS的机理。3.过渡金属改性SBA-15脱除低浓度COS的研究研究了过渡金属Zn、Fe、Co、Ni、Cu和Ag对SBA-15改性脱除COS的性能。结果表明：Ag/SBA-15对COS吸附效果最好。因此考察了Ag负载量、吸附温度、原料气的伴生组分C02对脱硫性能的影响。结果表明：Ag的负载量为40%时,吸附效果最好；最佳吸附温度为40℃；原料气中有CO2时,吸附剂对COS的吸附效果大大降低。4.吸附剂再生方法的研究用气体热再生的方法对失活后的吸附剂进行再生,考察了再生后吸附剂的脱硫性能。结果表明：碱改性ACF几乎不能再生,50%wtPEI/SBA-15经再生后吸附效果一般,Ag改性SBA-15再生后对COS吸附效果较差。更多还原

【Abstract】 Pure carbonyl sulfide (COS) is an organicacidity gas without odor and color. Its acidity and polarity are weak in H2S. Molecules are linear molecular structure. COS widely exists in many industrial gases which include natural gas, liquefied petroleum gas, coke oven gas and water gas. Because the materials and processes are different, the content also varies. Although its concentration is lower, it can’t be removed easily. Removing low concentration COS is key to realize fine desufurization if reducing the total sulfur of industrial gases and food-grade CO2. Thus, to remove low concentration COS is an important issue.On the basis of background of this paper, four aspects about how to remove low concentration COS have been studied. The main contents were listed as follows:1. A study of removal of low concentration COS by using modified ACF with alkaliThe activated carbon fibres were modified with some alkali such as NaOH、KOH、Na2CO3、K2CO3 by the impregnation method. Some factors which maybe affect the performance of removing carbonyl sulfide such as the kinds and the concentration of alkali, the adsorption temperature and the components of feed gas were investigated on the fixed-bed reactor. It was showed that the activated carbon fibres modified with 15%KOH had a higher breakthrough sulfur capacity than the others. The best adsorption temperature is 40℃. CO2 in feed gas decreased the COS adsorption capacity due to competition adsorption.2. A study of removal of low concentration COS by using modified SBA-15 with PEIThe SBA-15 were modified with PEI by the impregnation method and some factors which maybe affect the performance of removing COS such as the kinds and the concentration, the temperature of reaction, size of adsorbent and the components of feed gas were investigated on the fixed-bed reactor. It was showed that the 50%PEI modified SBA-15 had a higher sulfur capacity than others at room temperature. The best adsorption temperature is 60℃. When the size of adsorbent was 60-80 mesh, the desulfurization had a better effect. The result showed that chemical adsorption and physical adsorption occurred. CO2 in feed gas tremendously decreased the COS adsorption capacity due to competition adsorption. And the mechanism of removal carbonyl sulfide with PEI/SBA-15 was deduced.3. A study of removal of low concentration COS by using modified SBA-15 with transitional metalsThe SBA-15 were modified with transitional metals such as Zn、Fe、Co、Ni、Cu and Ag by the impregnation method and some factors which maybe affect the performance of removing COS such as the kinds and the concentration, the temperature of asdorption and the components of feed gas were investigated on the fixed-bed reactor. It was showed that the 40%Ag modified SBA-15 had a higher sulfur capacity than others at room temperature. The best adsorption temperature is 40℃. CO2 in feed gas greatly decreased the COS adsorption capacity due to competition adsorption.4. A study of regeneration method for sorbent using removing low concentration COSSorbent used to remove low concentration COS were regenerated with gas method. The experiment showed that ACF modified with some alkalis can not regeneration and 50% wtPEI/SBA-15 can regeneration. But the sulfur capacity of the sorbent is far away initial value. SBA-15 modified with 40%Ag had a bad regeneration.更多还原