【作者】 王存进；

【导师】 毛建新；

【作者基本信息】 浙江大学 ， 化学， 2010， 硕士

【摘要】 α-四氢萘酮是一种重要的合成中间体,可用于抗抑郁剂Sertraline、避孕药异炔诺酮-炔雌醇甲醚片、杀虫剂西维因、塑料软化剂等的合成。已有的文献表明,四氢萘空气氧化法以及苯和γ-丁内酯在AlCl₃的催化作用下可生成α-四氢萘酮,但是四氢萘空气氧化法转化率偏低,AlCl₃催化剂存在腐蚀设备、污染环境和难以重复使用等问题,其反应过程需要进一步绿色化。近年来,分子筛在酸催化的F-C反应中受到了较多的关注。分子筛是一种重要的固体酸,具有一定的酸性、规则的孔道以及较大的比表面积,在石油化工、精细化学品的合成领域应用广泛。而且根据需要可对分子筛的性质进行修饰,改变其酸量和孔道结构。分子筛具有较高的热稳定性,可以通过高温烧去积碳的方法再生,降低了工业成本。本文主要研究了在固定床反应器中苯与γ-丁内酯的反应,对催化剂的物化性质作了比较系统的表征,并讨论了酸催化条件下的反应规律,提出了可能的微观反应机理。主要研究内容和结果如下:1.采用等体积浸渍法将ZnCl₂负载到γ-Al₂O₃和活性碳的表面,将杂多酸H₃PW₁₂O₄₀负载到7-Al₂O₃的表面,在气固相固定床反应器中评价了催化剂的反应活性,结果表明:①33.3%ZNCl₂/γ-Al₂O₃和33.3%ZnCl₂/C对气固相苯和γ-丁内酯的反应具有较高的催化活性,但33.3%H₃PW₁₂O₄₀/γ-Al₂O₃不能催化该反应。②33.3%ZnCl₂/Al₂O₃在不同温度下的反应结果表明,在300-360℃的范围内,γ-丁内酯的转化率与温度呈负相关的关系。α-四氢萘酮的选择性和得率很低,产物中除丙苯、2-丁烯酸和α-四氢萘酮外尚有30%以上的产物,反应机理很复杂。2.酸性分子筛对苯和γ-丁内酯的气固相反应具有明显的催化作用,各种分子筛的催化结果存在较大差异,但主要产物是丙基苯（包括异丙苯和正丙苯）、2-丁烯酸和α-四氢萘酮。其中HZSM5分子筛对生成四氢萘酮具有较高的选择性和稳定性,提供了一种合成α-四氢萘酮的新方法。文中详细探讨了反应条件对转化率、得率或选择性的影响,并提出了可能的反应机理;另外,HZSM5（Si/Al=50）的水热处理、热处理、磷酸改性以及稀土元素改性也进行了较详细的研究。主要研究结果为:①HZSM5分子筛催化气固相苯和γ-丁内酯的反应以硅铝比Si/Al=50的反应结果最佳,HZSM5（Si/Al=50）在反应过程中出现失活现象,高温通入空气或O₂烧去积碳可将催化剂再生,再生使用具有较好的重复性。②磷酸改性、水热处理、热处理以及稀土元素改性等方法可提高分子筛的催化活性,而对产物的选择性没有很大影响。以水热处理和热处理改性得到了较高的活性和稳定性。③苯和γ-丁内酯的气固相反应可能的反应机理为:γ-丁内酯首先开环,与苯反应生成4.苯基丁酸,4-苯基丁酸发生分子内酰基化反应,关环生成α-四氢萘酮。苯和γ-丁内酯的气固相反应可能是E-R机理。反应过程中生成的丙烯和2-丁烯酸可能发生聚合,是导致分子筛失活的主要原因。3.分别采用NH₃-TPD、BET、XRD和O₂-TG等方法对酸性分子筛及其改性分子筛进行表征,结果表明:①不同硅铝比的HZSM5分子筛,硅铝比越小则酸量越大。②稀土元素改性、高温焙烧、水热处理以及磷酸改性等方法均可降低HZSM5分子筛的总酸量以及强酸中心和弱酸中心的数量,但不影响HZSM5分子筛的表面物相结构。③HZSM5（Si/Al=50）在反应前后以及再生后,表面物相结构没有发生变化,说明分子筛失活的主要原因是积焦或积碳。更多还原

【Abstract】 α-tetralone is an important synthesis intermediate,with wide application in antidepressant Sertraline、countraceptives、pesticides carbaryl and plastic softener. Reported methods showed thatα-tetralone can be synthesized by tetralin oxidation or F-C reaction of benzene andγ-butyrolactone under AlCl₃ catalysis.However,Tetralin oxidation method has a problem of low conversion and AlCl₃ is corrosive,polluting and it can not be reused,which is not favored by green chemistry.Recently,Zeolite has received much attention in F-C reaction.Zeolite is a kind of important solid acid with certain acidity,regular pore structure and high specific surface area,and has found wide application in petrochemicals and fine chemical synthesis.The physicochemical properties of zeolite can be modified by certain methods,leading to a change in acidity and pore structure.Zeolite is of high thermal stability so that it can be regenerated by O₂ oxidation at high temperature which will reduce the cost.In this paper we have investigated the vapor phase reaction of benzene withγ-butyrolactone.The properties of catalysts are systemically characterized.The results are discussed and a possible reaction mechanism is proposed.The main results are as follow:1.ZnCl₂ was supported on the surface ofγ-Al₂O₃ and active carbon.Heteroploy acid H₃PW₁₂O₄₀ was supported on the surface ofγ-Al₂O₃.The catalysts were evaluated in a fix bed reactor.The result showed that:①33.3%ZnCl₂/γ-Al₂O₃ and 33.3%ZNCl₂/C are highly effective in the vapor phase reaction of benzene withγ-butyrolactone while 33.3%H₃PW₁₂O₄₀/γ-Al₂O₃ do not catalyze the reaction.②By 33.3%ZnCl₂/γ-Al₂O₃ catalyst,in the temperature range of 300-360℃,the conversion is inversely correlated with temperature.The selectivity and yield ofα-tetralone is low.Besides propylbenzene（including isopropylbenzene and n-propylbenzene）、2-butenoic acid andα-tetralone,Over 30%of the product are unexpected and the reaction mechanism is very complex.2.The Acidic zeolites are apparently effective for the vapor phase reaction of benzene withγ-butyrolactone.The result may varied much among zeolites,but the major products are propylbenzene、2-butrnoic acid andα-tetralone.HZSM5 provides a new way for the synthesis ofα-tetralone with high selectivity and stability. The effects of reaction condition on conversion and selectivity are discussed and a possible reaction mechanism is proposed.The steam treatment、thermal treatment and phosphoric acid modification are investigated.The results are as follow:①HZSM5 is highly effective for the synthesis ofα-tetralone and the best silica to alumina ratio is 50.The deactivated HZSM5（Si/Al=50） can be regenerated simply by air or O₂ oxidation and its activity is recovered.②The steam treatment、thermal treatment and phosphoric acid modification exert a positive influence on the activity and selectivity,but no apparent effect is observed on the selectivity.The steam treatment and thermal treatment showed good activity and stability.③The possible reaction mechanism for vapor phase reaction of benzene with γ-butyrolactone is:γ-butyrolactone opens the ring and reacts with benzene to form 4-phenylbutyric acid by intermolucular alkylation;4-phenylbutyric acid producesα-tetralone by intramolucular acylation.The vapor phase reaction of benzene withγ-butyrolactone is proposed as E-R mechanism.Propene and 2-butenoic acid may be the precursors for the carbon deposition to make the catalyst deactivated.3.The acidic zeolites are characterized by NH₃-TPD、BET、XRD and O₂-TG. The result showed that:①For HZSM5 with different silica to alumina ratio,the acidic amount is inversely correlated with silica to alumina ratio.②The steam treatment、thermal treatment and phosphoric acid reduced the acidic amount of zeolite（both weak acidic center and strong acidic center）,but these treatment do not affect the bulk phase structure of HZSM5.③After the deactivation and regeneration,HZSM5（Si/Al=50） showed no change on the bulk phase structure so that the main reason for deactivation is carbon deposition on the surface of catalyst.更多还原