环戊烯催化氧化合成戊二醛及其动力学

对在非水溶剂存在下过氧化氢一步催化氧化环戊烯制备戊二醛过程中的催化体系进行了研究。考察了具有脱水功能的Ｂ２Ｏ３的作用及用量，确立了具有优良催化性能的催化体系ＷＯ３－Ｂ２Ｏ３；实验测定了反应动力学数据，采用非线性回归Ｐｏｗｅｌ共扼法求得了反应动力学方程。在推荐的催化剂体系和工艺条件下，环戊烯转化率６７％，戊二醛收率６３％，选择性９１％。     

由双环戊二烯制备环戊烷

对以双环戊二烯为原料,经解聚、加氢制备环戊烷的工艺进行了研究,重点考察了环戊二烯加氢条件。结果表明:在Raney镍催化剂加入量为0.5％～2％,加氢压力为0.5～3.0MPa,加氢温度为30～50℃时,环戊二烯的加氢转化率约为100％,加氢选择性也在99％以上,由双环戊二烯制备环戊烷的总收率>60％,产品的纯度在99％以上。     

Synthesis of maleic and pHthalic anhydrides from the mixture of cyclopentene and 1-pentene

The selective oxidations of cyclopentene, 1-pentene, and their mixture to maleic and phthalic anhydrides have been studied to gain information on the total utilization of olefins of C₅-fraction. The highest selectivities for maleic anhydride, a single major organic product, in individual oxidations of cyclopentene and 1-pentene were obtained at complete or almost complete conversion, and then the main byproduct was phthalic anhydride. The cooxidation of the mixture of cyclopentene and 1-pentene at ca. 100% conversion, which was selected as optimized condition, gave no interaction between cyclopentene and 1-pentene. This result indicates that two reactants can be simultaneously utilized at one oxidation unit process. In contrast, the cooxidation at low degrees of conversion gave some interaction. It was only related to the slightly stronger adsorption of cyclopentene as compared to 1-pentene.     

溶剂对环戊二烯加氢的影响

溶剂对环戊二烯（ＣＰＤ）液相加氢行为有明显的影响。在３０℃、１１０×１０５～１２３×１０５ＰａＨ２、骨架镍催化的条件下,ＣＰＤ在甲醇、乙醇、异丙醇、苯、甲苯等溶剂中的加氢反应是分步进行的。即先生成环戊烯（ＣＰＥ）,且对ＣＰＤ浓度表现为零级反应,再生成环戊烷（ＣＰＡ）。而在二氯乙烷、二氯甲烷中反应则没有明显的这种分步性。苯是较好的ＣＰＤ选择性加氢生成ＣＰＥ的溶剂。在ＣＰＤ∶苯＝２∶２５（体积比）、３０℃、１１０×１０５～１２０×１０５Ｐａ、骨架镍催化的条件下,ＣＰＥ的反应选择性达９９５％、摩尔收率达９０１％。     

Nonadiabatic reaction mechanisms of the O(3P) with cyclopentene

The reaction mechanism of the ground state oxygen atom O(³P) with cyclopentene is investigated theoretically. The triplet and singlet potential energy surfaces are calculated at the CCSD(T)//MP2/6-311G(d,p) level and the minimum energy crossing points (MECPs) between the two surfaces are located by means of the Newton–Lagrange method, from which the complex nonadiabatic reaction pathways are revealed. Based on the theoretical results, the most probable reaction mechanism of O(³P) with c-C₅H₈ is described, which agrees with the experimental results nicely, including the condensed phase experiment. At the same time, the newly revealed reaction mechanism clarifies the previous controversial product distribution, and predicts the possible existence of the new enol product, cyclopentenol.     

环戊二烯选择加氢生产环戊烯

以双环戊二烯为原料,经过解聚-精馏得到高纯度的环戊二烯,再以自制Ni/Al2O3为催化剂,对环戊二烯选择加氢制备环戊烯。对影响环戊二烯选择加氢的主要因素进行了研究。结果表明,控制反应温度35-45℃,氢气分压1.0-1.5 MPa,反应时间2 h左右,可实现环戊二烯的转化率〉97%,环戊烯的选择性大于95%。     

W-HMS催化剂的原位法制备研究

以钨酸为原料,通过原位合成法将W~(6+)引入六方介孔全硅分子筛HMS骨架中,制备了W- HMS催化剂。采用XRD、FT-IR以及EDS对所得催化剂结构进行了表征,并通过环戊烯过氧化氢非均相催化氧化制备戊二醛,考察了其催化活性。结果显示,W-HMS催化剂的催化性能与W的量密切相关．在n_(si)/n_w(物质的量比)大于或等于30时,催化剂保持了完好的HMS分子筛结构,W原子以嵌入HMS骨架的形式高度分散于载体内表面,构成催化活性中心,对环戊烯氧化反应转化率可达100%,生成戊二醛的选择性达79．3%。     

环戊二烯液相加氢制备环戊烯的研究

介绍了以工业级双环戊二烯为原料，经过解聚-精馏得到高纯度的环戊二烯，以骨架镍为催化剂，对环戊二烯液相加氢制备环戊烯的影响因素进行了研究。结果表明，在反应温度25～30℃，氢气分压为1．0。1．5MPa，无水乙醇作为溶剂，v无水乙醇：V环戊二烯为5～6：1，催化剂用量为4％。5％，搅拌速度为800r／min条件下，反应时间2～3h，环戊二烯的转化率大于98％，环戊烯的选择性大于95％。     

环戊烯合成环戊二酮工艺研究进展

介绍了环戊烯两步氧化法合成环戊二酮的反应机理及相应的催化剂和氧化剂的选择,综述了国内外在开发催化剂和氧化剂以及提高反应系统环保性方面的研究进展。     

环戊烯催化氧化合成戊二醛的研究进展

综述了以环戊烯为原料氧化合成戊二醛的各种方法,对各种催化氧化方法进行了分析、评述,总结了适合于工业化生产的方法。