【作者】 卢洲；

【导师】 张天永；

【作者基本信息】 天津大学 ， 应用化学， 2009， 硕士

【摘要】 萘酚（1-萘酚、2-萘酚）,是重要的精细化工中间体,广泛应用于医药、农药、染料、香料制造等行业。TiO₂作为光催化剂,在芳香化合物光催化羟基化方面的应用越来越受到重视。利用P-25型TiO₂对萘进行光催化,在不加H₂O₂的体系中,萘的转化率很低,仅有2%左右,加入适当浓度的H₂O₂,萘的转化率能提高至19.6%,1-萘酚的收率为2.5%左右。利用Photo-Fenton反应和Photo-Fenton-like反应对萘进行了光催化羟基化反应。考察了Fe²⁺或者Fe³⁺初始浓度、H₂O₂初始浓度、反应时间等不同因素对反应的影响。Fenton-like反应对萘的光催化羟基化比Fenton反应快。萘的转化率很大程度上取决于Fe²⁺或者Fe³⁺的初始浓度以及H₂O₂的初始浓度。在合适的Fe²⁺或者Fe³⁺以及H₂O₂初始浓度的情况下,萘的转化率能达到80%以上,1-萘酚收率4.6%。不管在Photo-Fenton反应还是Photo-Fenton-like反应体系中,紫外光照射对萘的转化率影响很小。利用浸渍法制备了Fe³⁺、Cu²⁺、Ag⁺掺杂P-25型TiO₂,发现经过掺杂催化剂晶型没有发生变化。Fe³⁺掺杂P-25光催化活性比P-25稍高,而Cu²⁺、Ag⁺掺杂P-25光催化剂以及通过溶胶-凝胶法制备的Fe³⁺、Cu²⁺、Ag⁺掺杂的锐钛矿型TiO₂,光催化活性均比P-25低。经过H₂O₂改性的锐钛矿型TiO₂和P-25相比,萘的转化率基本一致,但生成萘酚的选择性高。实验中制备的纳米CdS、介孔分子筛MCM-41对萘的光催化有一定活性,但萘的转化率5%左右,1-萘酚收率1.4%左右,都低于P-25的光催化活性。更多还原

【Abstract】 Naphthol（1-naphthol, 2-naphthol）, is an important fine chemical intermediate, widely used in medicine, pesticides, dyes, perfume manufacturing industry. Titanium dioxide catalysts have attracted a great deal of attention as a photocatalyst of hydroxylation of aromatic compounds.Hydroxylation of naphthalene in the presence of P-25 TiO₂ as photocatalyst was investigated. In the absence of H₂O₂, the naphthalene conversion was rather low, while proper H₂O₂ was added to the reaction system, naphthalene conversion, as well as 1-naphthol yield, enhanced rapidly.Hydroxylation of naphthalene using Photo-Fenton(Fe²⁺/H₂O₂) or Photo-Fenton-like(Fe³⁺/H₂O₂) reactions was investigated under neutral conditions. The effects of different systems variable initial concentration of Fe²⁺or Fe³⁺, initial concentration of H₂O₂, reaction time were studied. Hydroxylation of naphthalene in Photo-Fenton-like reaction was faster than Fenton reaction.The naphthalene conversion was strongly dependent on the initial concentration of Fe²⁺ or Fe³⁺, the initial concentration of H₂O₂. High naphthalene conversion was achieved at proper concentrations of Fe²⁺/Fe³⁺and H₂O₂. The UV irradiation had little effect on overall naphthalene conversion in the Fenton reaction or Fenton-like reaction.Fe³⁺, Cu²⁺, Ag⁺-doped P-25 was prepared by impregnation method. Compared metal-doped TiO₂ to P-25, there was no change in crystal form. While photocatlytic hydroxylation of naphthalene, Fe³⁺-doped P-25 photocatalytic activity was higher than the P-25, followed by Cu²⁺-doped P-25 and Ag⁺-doped P-25. We also prepared Fe³⁺, Cu²⁺, Ag⁺-doped anatase TiO₂ through the sol-gel method. Their photocatalytic activities were lower than P-25. The anatase TiO₂ modified by H₂O₂ is almost the same in the naphthalene conversion, but the selectivity of 1-naphthol increased.CdS, as well as mesoporous molecular sieve MCM-41, was prepared in the experiments. Although they all had photocatalytic activity in hydroxylation of naphthalene, much lower than P-25 photocatalytic activity.更多还原