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本文研究了乙丙橡胶第三单体乙叉降冰片烯的中间体-乙烯基降冰片烯含成液的分离和提纯过程,并得出最佳工艺条件。 相似文献
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以膦亚胺半茂钛为主催化剂、甲基铝氧烷为助催化剂、5-乙烯基-2-降冰片烯(VNB)为第三单体合成了乙烯-丙烯-VNB(E-P-VNB)三元共聚物。利用GPC,IR,DSC,1H NMR,13C NMR等方法分别研究了共聚单体及反应条件的影响、共聚物的硫化特性及耐热氧老化性能。实验结果表明,采用膦亚胺半茂钛催化体系成功合成了分子量高且分子量分布较窄的E-P-VNB。VNB的加入降低了乙丙共聚反应速率及收率,但VNB含量可达4.0%(w),催化活性在106 g/(mol·h)以上,未出现可见的凝胶,E-P-VNB中无规结构单元占主导地位。E-P-VNB硫化胶的硫化速度快,交联密度大,高温压缩永久变形小,回弹性和物理机械性能好,耐热氧老化性能更优。 相似文献
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《石油化工》2017,(6)
采用两种苯胺邻位取代基是二苯甲基的α-二亚胺镍配合物作为主催化剂,甲基铝氧烷为助催化剂,实现了降冰片烯均聚合及其与1-己烯的共聚合。考察了聚合温度、铝镍比、溶剂对降冰片烯均聚合活性的影响,以及聚合温度、共聚单体比例对降冰片烯与1-己烯共聚合活性的影响。采用FTIR,13C NMR,DMA等表征了聚合物的结构,并测试了聚合物的玻璃化转变温度、相对分子质量和热稳定性。实验结果表明,聚合是按照加成方式进行的,催化剂具有很好的热稳定性,在较高的聚合温度下,聚合活性依然很高,且在含氯溶剂中的活性也较高。在共聚合中,1-己烯加入量的增加使得催化剂活性以及聚合物的玻璃化转变温度降低,但1-己烯在共聚物的比例较低。 相似文献
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李琴梁春超姜湃胡博文杨敏刘宾元 《石油化工》2017,(6):701-707
采用两种苯胺邻位取代基是二苯甲基的α-二亚胺镍配合物作为主催化剂,甲基铝氧烷为助催化剂,实现了降冰片烯均聚合及其与1-己烯的共聚合。考察了聚合温度、铝镍比、溶剂对降冰片烯均聚合活性的影响,以及聚合温度、共聚单体比例对降冰片烯与1-己烯共聚合活性的影响。采用FTIR,13C NMR,DMA等表征了聚合物的结构,并测试了聚合物的玻璃化转变温度、相对分子质量和热稳定性。实验结果表明,聚合是按照加成方式进行的,催化剂具有很好的热稳定性,在较高的聚合温度下,聚合活性依然很高,且在含氯溶剂中的活性也较高。在共聚合中,1-己烯加入量的增加使得催化剂活性以及聚合物的玻璃化转变温度降低,但1-己烯在共聚物的比例较低。 相似文献
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V_2O_5催化烷基化合成2,3,5-三甲基苯酚的研究 总被引:1,自引:0,他引:1
制备并考察了甲醇烷基化法合成2,3,5-三甲基苯酚系列固体酸催化剂,筛选出烷基化反应适宜的催化剂,对催化剂载体进行了扩孔实验,并进行了烷基化反应工艺条件的优化研究。筛选出的催化剂以V2O5为主催化剂,Cr2O3为助催化荆,γ-Al2O3为载体。实验结果表明,载体的孔结构对产物的选择性有明显的影响;最优工艺条件:反应温度350℃、液态空速0.29 h-1、n(3,5-二甲基苯酚)/n(甲醇)/n(水)=1/2/1;原料3,5-二甲基苯酚的转化率达95.89%,目的产物2,3,5-三甲基苯酚的收率为70.92%。 相似文献
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I. Yu. Shchapin O. V. Makhnach V. L. Klochikhin Yu. G. Osokin A. I. Nekhaev 《Petroleum Chemistry》2008,48(1):71-82
Cyclic and distonic forms of radical cations were recorded by ESR in x-ray irradiated frozen solutions (1.0 vol %) of 5-vinyl-2-norbornene (VNB) and 2-vinylnorbornane in Freon 113 (CFCl2CF2Cl). In both cases, mixtures of isomers in a ratio of endo-: exo-= 66: 34 were used. It was shown that, in the general case, the endo-VNB radical cation rearranges into the radical cation of cis-3a,4,7,7a-tetrahydroindene through a multistage mechanism involving the intermediate formation of the distonic radical cation, not via the earlier suggested one-stage concerted mechanism. The interconversions of endo-and exo-VNB in γ-irradiated solutions of VNB in CCl4 were studied chromatographically. A general scheme of VNB transformations with allowance for the intermediate formation of the cyclic and distonic forms of the VNB radical cations is proposed. It was found that the structures of the radical cation distonic form and VNB homopolymer are identical, a resemblance that indicates the occurrence of VNB polymerization via the radical cation mechanism during its γ-irradiation. 相似文献
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I. Yu. Shchapin O. V. Makhnach V. L. Klochikhin Yu. G. Osokin A. I. Nekhaev 《Petroleum Chemistry》2007,47(2):92-98
It was found that the main products of γ-radiolysis (60Co) of liquid 5-vinyl-2-norbornene (VNB) and 5-ethylidene-2-norbornene (ENB) and their solutions in cyclohexane and benzene are polymers. The structure of these polymers was determined by means of IR spectroscopy. It was shown that the polymerization of individual VNB engages both C=C bonds of the diene and involves norbornene ring opening. In the case of individual ENB, only one, exo-cyclic, C=C bond participates in polymerization retaining the norbornene ring intact. In cyclohexane solutions, mixtures of VNB and ENB polymers of the same type are formed, which are predominantly composed of saturated compounds. It was found that polymerization during γ-irradiation of VNB solution in benzene proceeds via the addition of benzene radicals to one, endo-cyclic, C=C bond of VNB. The produced 2-vinylnorbornane moiety of this polymer was identified via comparison of its IR spectrum with that of unirradiated 2-vinylnorbornane. 相似文献
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在小型固定床反应器上采用纳米HZSM-5分子筛催化剂对混合二异丙苯进行选择催化裂化制间二异丙苯,考察了反应温度和重时空速对选择催化裂化反应的影响,得到的优化反应条件为:常压、反应温度420℃、重时空速3h~(-1)、氮气为载气。在此条件下,8h内的平均结果为:对二异丙苯裂化率89.8%,间二异丙苯收率72.7%,二异丙苯产物中间二异丙苯的质量分数90.2%。反应工艺的研究结果表明,在无载气的条件下,原料中通入苯可减少反应过程的积碳。对纳米HZSM-5分子筛催化剂进行改性的实验结果表明,采用水热处理12h的改性方法可有效提高催化剂的催化性能和稳定性,同时产物中间二异丙苯的含量很高,可有效提高后续分离过程的效率。 相似文献
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采用“沉淀-浸渍”法制备SO42-/ZrO2-Al2O3催化剂,在常压、200 ℃的反应条件下,通过改变载气类型和数量,在固定床微型反应评价装置上考察了载气气氛对SO42-/ZrO2-Al2O3催化正丁烷异构化反应性能的影响。实验结果表明,惰性的氮气仅仅起到稀释原料和中间产物浓度的作用;而氢气在该反应中是非惰性的,除稀释作用外,还与催化剂发生相互作用,既能与正丁烷分子在活性中心上发生竞争吸附,还能提高中间物种和产物分子从催化剂表面上脱附下来的能力,从而减缓催化剂的失活速率。其中,与催化剂的相互作用是其提高催化剂稳定性的关键因素。 相似文献
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用5%Na2WO4-2%Mn/SiO2颗粒催化剂和3%Ce-5%Na2WO4-2%Mn/SBA-15/Al2O3/FeCrAl金属基整体式催化剂,构建了一种颗粒/整体式新型双层床新型甲烷氧化偶联催化反应器,评价了双层床反应器中甲烷氧化偶联反应性能,重点考察了催化剂床层高度、原料气的流向方式、反应温度、烷氧比、进料流量等与反应性能的关系。结果表明,颗粒催化剂床层高度为15mm、整体式催化剂床层高度为50mm,原料气先通过颗粒床层再通过整体式床层的方式下,具有最好的反应性能,甲烷转化率为38.4%时,乙烯选择性可达41.5%,比单床层催化剂的综合性能有明显提高。 相似文献
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F. Shayegh 《Petroleum Science and Technology》2013,31(8):928-935
Nowadays converting synthesis gas to makes olefins is an important issue and researcher has been focused on it. The kinetic experiments for synthesis gas reactions over RIPI-Co/Mn catalyst to light olefin are carried out in a micro-fixed-bed reactor under the following conditions: temperature 220–300°C, pressure 1–5 atm, H2/CO feed ratio 1–3, and space velocity of 450-600 h?1. In order to obtain the parameters of the kinetic model, the optimum values of the kinetic parameters have been obtained. The global minimum for the optimized function has been achieved, with using the genetic algorithm. The data of this study were best fitted by a Langmuir-Hinshelwood (LH) rate form Rco = kPcoPH21/2/ (1+aPco+bPH21/2)2. 相似文献