【作者】 仇念海；

【导师】 宋华；

【作者基本信息】 东北石油大学 ， 化学工艺， 2013， 博士

【摘要】 氧化反应在有机化学品的合成工业中占有极其重要的地位。同时,氧化过程也是导致环境污染最严重的因素之一。传统氧化剂锰和铬的氧化物和盐类的主要缺点是选择性差、需要较苛刻的反应条件、对人和环境有强烈的危害。因此,使用各类绿色氧化剂,如氧气、过氧化氢等,代替传统氧化剂,是实现环境友好的关键技术。本文以过氧化氢为氧化剂,以环己烷选择性氧化合成环己酮和环己醇为模型反应,系统研究了六种不同催化剂对环己烷选择性氧化反应性能的影响。以金属盐为催化剂的实验结果表明,在30%过氧化氢氧化环己烷合成环己酮反应中,硫酸亚铁是一种较好的催化剂。氧化反应的适宜条件为：丙酮10mL,环己烷0.20mL,硫酸亚铁0.02g,30%过氧化氢0.50mL,反应温度80℃,反应时间10h。在此条件下,氧化反应的转化率达35.35%,环己酮和环己醇的选择性为94.06%。以环己烷氧化合成环己酮和环己醇为模型反应,研究了钨酸和CDM-5的复配体系的催化性能,发现钨酸为主催化剂,CDM-5为助催化剂时的反应效果最好。氧化反应的适宜条件为：丙酮10mL,环己烷0.2mL,钨酸0.02g和CDM-50.01g,30%过氧化氢1.0mL,反应温度70℃,反应时间9h。此时氧化反应的转化率达49.40%,环己酮和环己醇的选择性为96.08%。用离子交换法制备了Cu/HZSM-5分子筛催化剂,并对催化剂进行了XRD、 FT-IR、BET、ICP、TG/DTA等表征。表征结果表明,CuO的晶化发生在300和400℃之间；分散在HZSM-5分子筛中的Cu物种与分子筛存在多种配位键合作用。Cu/HZSM-5催化剂的最佳制备条件为：Cu担载量10%,离子交换温度80℃,离子交换时间8h,焙烧温度600℃。在环己烷0.5mL,乙腈10mL, Cu/HZSM-5催化剂0.03g, H2O24mL,反应温度65℃下反应6h,环己烷转化率为43.1%,环己酮和环己醇的总选择性为95.7%。用浸渍法制备了Co-Mo/V2O5复合催化剂,并对催化剂进行了XRD、FT-IR.BET等表征。表征结果表明,掺杂组分Co和Mo与纯V205作用生成了具有催化活性但晶相不完整的复合金属氧化物CoMoO4(2θ=28.51°)和CoMoO3(2θ=18.06°)的特征峰。Co-Mo/V2O5催化剂的最佳制备条件为：Mo的掺入量为20%,Co的掺入量为5%,浸渍时间为1h,焙烧温度为600℃。在环己烷0.5mL,乙腈10mL,Co-Mo/V2O5催化剂0.03g, H2O23mL,反应温度为55℃下反应3h,环己烷的转化率为39.1%,环己酮和环己醇的总选择性为100%。用浸渍法制备了CuPMo/V2O5复合催化剂,并对催化剂进行了XRD、FT-IR、 BET等表征。表征结果表明,组合改性并没有破坏V205的结构,PMo和CuO都高度分散于V205上。CuPMo/V2O5催化剂的最佳制备条件为：浸渍时间12h,焙烧温度320℃。在环己烷0.5mL,乙腈10mL, CuPMo/V2O5催化剂0.03g, H2O23mL,反应温度65℃下反应3h,环己烷转化率为53.6%,环己酮和环己醇的总选择性为100%。用浸渍法制备了金属改性VPO催化剂,并对催化剂进行了XRD、FT-IR、钒价态分析、电镜分析等表征。表征结果表明,金属铋对催化剂的改性效果最好,铋的加入可以使催化剂中具有适宜比例的V4+和V5+,能增加氧物种含量。VPO催化剂最佳制备条件为：Bi/V=0.1, P/V=0.9,还原温度为120℃C,焙烧温度400℃,还原时间12h。催化剂前躯体由(VO)2H4P2O7组成,活化后催化剂主要的活性相为VOPO4。以环己烷为原料,过氧化氢为氧化剂,所制备得到的Bi-VPO为催化剂,研究了溶剂种类及用量、催化剂用量、氧化剂双氧水用量、反应温度以及反应时间等工艺条件对环己烷氧化反应的影响,确定了适宜的工艺条件。在反应温度65℃,原料环己烷用量0.60mL,催化剂用量0.0150g,溶剂丙酮10.00mL,氧化剂双氧水3.00mL下,反应8h,环己烷转化率为81.4%,环己酮收率为58.2%,环己醇收率为23.2%。更多还原

【Abstract】 Oxidation reaction plays an important role in the organic synthesis industry. It is one of the main factors that cause the environmental pollution as well. This is an important area, as low selectivity of reaction, demands of rigorous experimental conditions and harm to mankind and the environment have made the replacement of traditional oxidants, such as Cr and Mn oxides and compounds, a paramount problem. Therefore, various green oxidants, such as oxygen, hydrogen peroxide etc, are applied to reach the friendly environment goal. In this paper, six catalysts were successfully prepared, and which were applied to catalyze selective oxidation of cyclohexane to cyclohexanone and cyclohexanol using oxygen. These catalysts were characterized by a series of methods, the effects of catalyst preparation conditions and oxidation reaction parameters on their catalytic performances were investigated in cyclohexane oxidation to cyclohexanone and cyclohexanol using oxygen as the oxidant. In this work, we have used the selective oxidation of cyclohexane to cyclohexanone and cyclohexanol over hydrogen peroxide, to systematically investigate the catalytic performance of six kinds of catalysts.In this using30%hydrogen peroxide to oxidate cyclohexane to cyclohexanone experiment, ferrous sulfate is a preferable catalyst. Using10ml of acetone,0.20mL of cyclohexane,0.02g of ferrous sulfate,0.5mL of30%hydrogen peroxide at a reation temperature of80℃for10h, the conversion of cyclohexane was35.35%and the total selectivity to cyclohexanone and cyclohexanol was94.06%.In the reaction of oxidizing cyclohexane by30%hydrogen peroxide, the combination of using tungstic acid as catalyst and CDM-5as assistant catalyst was the best. The conversion of this oxidation is49.40%and the selectivity to cyclohexanone and cyclohexanol was96.08%when we use lOmL of acetone,0.2mL of cyclohexane,0.02g of tungstic acid,0.01g of CDM-5,1.0mL of30%hydrogen peroxide at a reation temperature of70℃for9h.The catalyst supported on HZSM-5molecular sieves (Cu/HZSM-5) was prepared by ion exchange and characterized by XRD, BET, ICP, FT-IR and TG/DTA. It is proposed that CuO crystallization occurs between300and400℃, and there exist various ligand bonds interactions between the copper species and the molecular sieve matrix. Cu/HZSM-5exhibits the best performance when the Cu(copper nitrate) loading is10%, the ion exchange temperature reaches80℃, reaction time reaches8h and the calcination temperature reaches600℃. Using0.5mL of cyclohexane,10mL of acetonitrile,4ml of hydrogen peroxide and0.03g of catalyst at a reaction temperature of65℃for6h, the cyclohexane conversion was43.1%and the total selectivity to cyclohexanol and cyclohexanone was95.7%.The new type of Co-Mo/V2O5catalyst was prepared by impregnation method and characterized by XRD, BET and FT-IR. It is observed that the incomplete crystalline phase CoMoO4(2θ=28.51°) and CoMoO3(2θ=18.06°) have catalytic activity, demonstrating that there is interaction between pure V2O5and doped components. The Co-Mo/V2O5catalyst exhibits the best performance when the Mo loading is20%and Co loading is5%, the immersion time reaches1h and the calcination reaches600℃. Using0.5mL of cyclohexane,3mL of hydrogen peroxide and30mg of catalyst at a reaction temperature of55℃for3h, the cyclohexane conversion was39.1%and the total selectivity to cyclohexanol and cyclohexanone was100%.The CuPMo/V2O5catalyst was prepared by impregnation method and characterized by XRD, BET and FT-IR. It is observed that PMo and CuO were well dispersed on the surface of V2O5, thus indicating that the doping components had no obvious effect on the original structure of V2O5. The CuPMo/V2O5catalyst exhibits the best performance when it is impregnated at room temperature for12h and calcinated at320℃. Using0.5mL of cyclohexane,3mL of hydrogen peroxide and30mg of catalyst at a reaction temperature of65℃for3h, the cyclohexane conversion was53.6%and the total selectivity to cyclohexanol and cyclohexanone was100%.In this work, the VPO catalyst and the Bi-promoted VPO catalyst were prepared, and these catalysts were investigated by means of XRD, FT-IR, the determination of average valence state of vanadium and electronic speculum. It is indicated the addition of Bi has a positive effect on the catalyst, which will adjust the ratio of V4+/V5properly, thus increasing the content of oxides. The VPO catalyst exhibits the best performance under the condition of Bi/V=0.1, P/V=0.9at reduction temperature of120℃and calcination temperature of400℃for12h. The main property of the catalyst precursor is (VO)2H4P2O7, and it was converted to VOPO4, playing as the active phase.By preparing the Bi-VPO catakyst in advance, the aim of this work is to investigate the effect of solvent and its dosage, the catalyst and hydrogen peroxide dosage, reaction temperature and reaction time on reaction. In the end, with the optimized condition of using0.6mL of cyclohexane,0.015g of Bi-VPO, lOmL of acetone,3.0mL of30%hydrogen peroxide, at a temperature of65℃for8h, the cyclohexane conversion was81.4%, the cyclohexanone yield was58.2%and the cyclohexanol yield was23.2%.更多还原