锡卟啉的合成及其绿色催化氧化环己烯

考察催化剂金属锡次卟啉二甲酯催化氧化环己烯的反应性能。探讨了在催化氧化过程中,反应温度、压力、时间、催化剂用量等因素对环己烯转化率和产物选择性的影响,并结合GC-MS在线分析检测。结果表明,当温度100℃、压力0.8 MPa、时间7 h、催化剂用量0.5 mg(7.6×10-4mmol)、环己烯10 mL(98 mmol)的条件下,环己烯的转化率达84%,相应产物2-环己烯-1-醇和2-环己烯-1-酮的总选择性为94%,并对该反应的催化氧化反应机理进行了初步研究。     

十聚钨酸季铵盐催化环己烯合成己二酸的研究

研究了以十聚钨酸季铵盐为催化剂、30%H2O2为氧源催化氧化环己烯合成己二酸的反应,考察了含不同阳离子的十聚钨酸季铵盐的催化效果、反应时间、十聚钨酸季铵盐的用量、反应温度和30%H2O2用量等对环己烯选择性催化氧化反应的影响。结果表明,以十聚钨酸季铵盐([Bmim]4W10O32)为催化剂,在55℃,十聚钨酸季铵盐0.0690mmol,反应10h,30%H2O2用量90mmol,环己烯的用量20mmol,环己烯的转化率为100%,己二酸的选择性达到97.2%。     

含两个质子酸位的离子液体与钨酸钠催化环己烯合成己二酸

研究了含两个质子酸的离子液体与钨酸钠催化环己烯合成己二酸的反应,考察不同离子液体、离子液体用量、反应温度和反应时间等对环己烯选择性氧化反应的影响。结果表明,以离子液体1-甲基-3-丙酸咪唑对甲苯磺酸盐{［C₁imCH₂CH₂COOH］TSO}和钨酸钠为催化剂,在80 ℃、离子液体用量7.5 mmol和钨酸钠用量2.5 mmol时,反应10 h,环己烯转化率100%,己二酸选择性达96.8%。催化剂循环使用4次,催化活性基本不变。     

“一锅法”合成双金属催化剂Co-Ti-SBA-15及其环氧化性能研究

以硝酸钴和钛酸四丁酯为金属前驱体,采用"一锅法"制备了Co-SBA-15-(180)、Ti-SBA-15-(36)和Co-Ti-SBA-15-(30)-(5)催化剂,并用于催化烯烃环氧化反应中。采用N_2吸附脱附、X-射线衍射、透射电子显微镜、扫描电子显微镜和X-射线能谱技术对催化剂进行表征。结果表明,在反应温度为80℃、1,2-二氯乙烷用量为10 mL、催化剂质量为100 mg、环己烯物质的量为10 mmol、叔丁基过氧化氢物质的量为10 mmol、反应时间为8 h的条件下,Co-Ti-SBA-15-(30)-(5)双金属催化剂对环己烯进行环氧化的转化率和选择性分别达到了92. 70%和94. 67%,明显高于Co-SBA-15-(180)和Ti-SBA-15-(36)单金属催化剂。     

改性聚苯乙烯-二乙烯苯纤维固载过氧磷钨酸催化剂的制备及其催化环己烯环氧化反应的研究

以改性聚苯乙烯-二乙烯苯纤维为载体,过氧磷钨酸为活性组分,合成了一种新的固载型过氧磷钨酸催化剂—{PO4[WO(O2)2]4｝3-}/PSN,通过红外、热重-差热、比表面及孔径测试等方法对其结构进行了分析,通过能谱仪测定了其中氮、磷、钨等主要元素的含量.将该催化剂应用于环己烯环氧化反应中,以过氧化氢为氧化剂,考察了催化剂用量、助剂用量、反应时间、反应温度等工艺条件.实验结果表明该催化剂对环己烯环氧化反应显示出较高的催化性能,在n(环己烯)∶n(过氧化氢)=1.75∶1,m(催化剂)∶m(原料)=1∶20,m(助剂)∶m(催化剂)=1∶10,反应温度60℃,反应时间5h的条件下,环己烯转化率可达88％,产物中环氧环己烷选择性达96.5％,重复使用十次催化性能无明显下降.     

分子氧氧化环己烯气-固催化反应的工艺研究

针对环己烯在气-液-固催化氧化反应中存在的问题,该文采用微分反应器,在自行研制出的催化剂的基础上,于无溶剂、无共还原剂的条件下,对分子氧氧化环己烯的气-固催化氧化反应进行了研究,考察了影响该反应的多种因素,得到较佳的工艺条件为:催化剂用量1.5g,反应温度110℃,环己烯流量0.04mL/min,氧气流量10mL/min。在该条件下,环己烯的一次转化率为20%,目的产物2-环己烯-1-醇和2-环己烯-1-酮的选择性为60%。该文报告工作的新颖性已为河南科学院化学研究所于2008年5月23日出具的第HIC 2008018号《科技查新报告》所证实。     

大环双核Cu(Ⅱ)催化剂的制备及催化性能

合成了大环双核铜(Ⅱ)催化剂—{[Cu(Ⅱ)aneN5]2(DDS)}(ClO4)4,用元素分析和红外光谱对其结构进行了表征。常压条件下,以制得的催化剂催化分子氧氧化环己烯合成环己烯酮,考察了催化剂用量、反应时间、反应温度、溶剂用量等因素对环己烯酮合成的影响。优化得到较佳合成工艺条件为:O2流速大约5 mL/min,以环己烯4 mL计,催化剂2 mg,反应时间12 h,反应温度338 K,乙腈12 mL。环己烯的转化率为65.9%,环己烯酮的选择性为78.3%。     

双醛淀粉Schiff碱钴配合物催化环己烯环氧化反应

合成了双醛淀粉Schiff碱钴配合物,并利用FT-IR、UV-vis对其结构进行了表征。以该配合物为催化剂,H_2O_2为氧化剂,异丁醛为助氧化剂,研究了乙腈溶液中环己烯的环氧化反应,考察了催化剂用量、温度、物料比等参数对环氧化反应的影响。结果表明:制备环氧环己烷的最佳工艺条件是催化剂用量20 mg,n(H_2O_2)∶n(环己烯)=2∶1,n(异丁醛)∶n(环己烯)=2∶1,温度60℃,时间6 h。在此条件下,环己烯的转化率为53.8%,环氧环己烷的选择性为61.2%。     

双金属Mo-Ti-SBA-15的制备及催化环己烯环氧化性能

采用一步法分别制备了单金属介孔催化剂Ti-SBA-15-(36)、Mo-SBA-15-(180/28)和双金属介孔催化剂Mo-Ti-SBA-15-(X)。考察了双金属催化剂Mo-Ti-SBA-15-(X)中Mo含量对催化剂结构和催化性能的影响;分析了催化剂活性差异的原因并探讨了双金属催化剂的协同催化机理。对影响催化环氧化反应的主要因素进行了考察。结果表明:双金属催化剂Mo-Ti-SBA-15-(180/28)在环氧化反应中的催化效果优于单金属催化剂。当反应时间为8 h、反应温度为80℃、催化剂剂量为25 mg、以2.5 mmol环己烯为底物、叔丁基过氧化氢(TBHP)为氧源、1,2-二氯乙烷为溶剂时,Ti-SBA-15-(36)、Mo-SBA-15-(180/28)和Mo-Ti-SBA-15-(180/28)为催化剂对应的环己烯转化率分别为41.07%、46.44%和98.33%,选择性分别为97.56%、93.19%和98.86%。Mo-Ti-SBA-15-(180/28)催化剂经过5次循环利用,环己烯的转化率和选择性均超过95%和97%,说明该催化剂具有很好的可循环利用性。     

钌催化剂上苯加氢制环己烯的影响因素

综述了钌催化剂上苯选择性加氢的反应机理、催化剂制备过程中前躯体、制备方法、载体、添加剂(水,有机添加剂,无机添加剂)对催化剂催化性能的影响和反应过程中温度、压力、搅拌速率、催化剂用量及反应时间等对苯转化率、环己烯选择性和环己烯收率的影响。     

Chromium modified silica from rice husk as an oxidative catalyst

RH-Cr and RH-Cr500 were synthesized from rice husk by solvent extraction and gel precipitation technique. The specific surface area of RH-Cr and RH-Cr500 were found to be 0.542 and 1.20 m² g⁻¹ respectively. Energy dispersive X-ray (EDX) analysis showed that Cr(III) was homogenously incorporated in the matrix of both samples to a maximum of ca. 16% in RH-Cr500. Elemental analysis showed that RH-Cr contained ca. 15% carbon, while RH-Cr500 contained negligible amounts. FTIR analysis showed the extracted solid contained silanol (Si–OH) and siloxane (Si–O–Si) groups. Catalytic oxidation of cyclohexane with H₂O₂ using RH-Cr as the catalyst showed a 27.13% conversion to cyclohexanone and cyclohexanol with a selectivity of 57.37% and 42.63% respectively. However, RH-Cr500 showed only 14.01% conversion but with a selectivity of 64.83% of cyclohexanone and 35.17% of cyclohexanol. Epoxidation of cyclohexene using H₂O₂ with RH-Cr as the catalyst gave a conversion rate of 30.17% with a selectivity of 11.51% towards cyclohexene oxide, 63.21% 2-cyclohexen-1-one and 25.29% 2-cyclohexen-1-ol. The same reaction with RH-Cr500 as the catalyst showed 21.28% conversion with 14.65% cyclohexene oxide, 68.71% 2-cyclohexen-1-one and 16.64% 2-cyclohexen-1-ol. In the catalytic oxidation of cyclohexanol to cyclohexanone, RH-Cr showed a conversion of 12.25% while RH-Cr500 showed a conversion of 13.52%. No others products were detected in the conversion. Comparison with published catalytic systems showed that RH-Cr and RH-Cr500 to be a better catalyst even though the surface area of these catalysts were low.     

Efficient liquid phase oxidation of olefins and aromatic alcohol catalyzed by reusable polymer anchored Schiff base complexes

BACKGROUND: Heterogenization of homogeneous catalyst has become an interesting process for the catalytic oxidation of olefins and aromatic alcohol. This may provide a new kind of catalyst that is not only friendly to the environment but also exhibits higher thermal and chemical stabilities. RESULTS: Polymer anchored Schiff‐base complexes of iron(III), copper(II) and cobalt(II) have been synthesized and characterized. The catalytic potential of these complexes has been tested for the oxidation of cyclohexene. The effect of varying solvent, oxidant, substrate oxidant molar ratio, temperature and catalyst amount has been studied. Under optimized reaction conditions 91, 88 and 81% conversion of cyclohexene was obtained with Fe(III), Cu(II) and Co(II) catalysts, respectively. Moreover, the oxidation of other substrates, such as styrene, benzylalcohol, toluene and 1‐hexene were also efficiently carried out by these catalysts. CONCLUSION: The immobilized complexes showed excellent catalytic activity along with high selectivity for the oxidation of olefins and alcohols. The catalysts can be recycled more than five times without any noticeable loss of catalytic activity. Copyright © 2009 Society of Chemical Industry     

离子热合成CdMoP复合氧化物及其催化性能研究

采用离子液体热合成法制备了新型镉钼磷（CdMoP）系列复合氧化物催化剂,并通过FT-IR、XRD、SEM、TEM及XPS等表征手段对催化剂物化性质进行表征。由表征结果可知离子液体不仅能够进入CdPMo-80催化剂骨架,同时还能将P元素固定于催化剂中,从而呈现出有序增长的层状结构且拥有较多强酸中心。将以环己烯氧化制备环氧环己烷为探针反应,考察了CdMoP-80复合金属氧化物催化剂的催化性能。结果表明,在催化剂用量0.2 g,质量分数为30%的过氧化氢4 mL,环己烯2 mL,乙腈4 mL,55 oC条件下反应4 h后定性定量分析,环己烯的转化率为99.2%,环氧环己烷的选择性为97.0%。     

席夫碱钼(Ⅵ)配合物催化合成环氧环己烷

以合成的水杨醛缩2-氨甲基吡啶席夫碱钼配合物([MoO_2(L_1)(EtOH)])、邻羟基苯乙酮缩2-氨甲基吡啶席夫碱钼配合物([MoO_2(L_2)(EtOH)])、2-吡啶甲醛缩邻氨基酚席夫碱钼配合物([MoO_2(L_3)(EtOH)])为催化剂,研究了叔丁基过氧化氢(TBHP)作氧化剂时3种配合物在制备环氧环己烷中的催化活性。3种席夫碱配合物中[MoO_2(L_3)(EtOH)]的催化活性最高。详细考察了反应时间、温度、催化剂用量、氧化剂用量对环己烯转化率、环氧产物选择性的影响,筛选出了席夫碱钼催化剂最佳的反应条件:70℃,10 mg[MoO_2(L_3)(EtOH)],n(环己烯)∶n(叔丁基过氧化氢)=1∶2,反应5 h,环己烯的转化率为77.2%,环氧环己烷选择性99%,产率为77.2%。催化剂重复使用性实验表明,该席夫碱配合物具有较高的稳定性。     

谷氨酸型杂多酸盐催化氧化环己烯合成己二酸

将L-谷氨酸和磷钨酸反应合成了谷氨酸型杂多酸盐([HGlu]PTA)催化剂,并催化氧化环己烯合成己二酸,探讨了催化剂的催化性能,考察了催化剂用量、反应时间对合成己二酸的影响。结果表明:[HGlu]PTA催化剂催化氧化环己烯合成己二酸具有良好的催化效果;在不加任何配体或相转移剂前提下,在环己烯100 mmol,30%双氧水44.5 mL,[HGlu]PTA 5 mmol,回流温度90℃,反应时间9 h条件下,己二酸分离产率可达94.76%;[HGlu]PTA催化剂重复使用4次后,己二酸的产率仍然可达到80%以上。     

Copper-cationic salphen catalysts for the oxidation of cyclohexene by oxygen

The modified copper-cationic salphen catalysts were synthesized and used in the allylic oxidation of cyclohexene to 2-cyclohexen-1-ol and 2-cyclohexen-1-one with oxygen under mild conditions. Compared with their unmodified counterpart, the catalytic activities of modified catalysts are improved. The type of counteranion could affect the reactivity of catalyst, which offers an opportunity to improve the catalysts via changing counteranions to optimize the selectivity. The cation–anion interaction can be adjusted by different solvents, which in turn influences the catalyst reactivity. Furthermore, these novel catalysts can be reused without sacrificing the activity.     

分子氧氧化环己烯制备环己烯酮

针对分子氧氧化环己烯制备环己烯酮的催化反应体系,以Co(Ⅱ)为活性中心,3,5-二氯水杨醛与邻苯二胺为配体,胺化的MCM-41型介孔分子筛为载体,用化学键联法制备出一种固载型希夫碱催化剂。进而考察了该催化剂对分子氧氧化环己烯制备环己烯酮的工艺条件,结果表明,在常压、催化剂用量0.15 g(2 mL环己烯)、乙腈20 mL、氧气流量5 mL/min、反应温度60℃、反应时间8 h、叔丁基过氧化氢(TBHP)0.04 mL的条件下,环己烯酮的单程收率达54.87%,催化剂容易分离回收,可重复使用。     

Allylic Oxidation of Cyclohexene with Molecular Oxygen Using Cobalt Resinate as Catalyst

Allylic oxidation of cychohexene under atmospheric pressure of molecular oxygen was carried out over cobalt resinate in the absence of solvent. It was shown that cobalt resinate exhibited promising catalytic activity for the oxidation of cyclohexene to 2-cyclohexen-1-ol and 2-cychohexen-1-one under mild condition for the first time.