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碳四烷烃包括正丁烷和异丁烷,主要来自炼油厂和石化装置。目前大部分碳四烷烃的利用途径单一,大多用作燃料等低值消耗,未能实现碳四烷烃资源的高值化利用。随着化工行业产品精细化率的发展、资源利用率的提高,碳四烃类化合物的综合利用日益受到人们的关注。针对碳四烷烃资源的化工利用现状,本文介绍了碳四烷烃催化氧化制备有机化工产品的技术进展,包括正丁烷氧化制备顺酐和乙酸、异丁烷氧化制备甲基丙烯酸和叔丁基过氧化氢等。总结了碳四烷烃催化氧化技术的特点,认为温和条件下的仿生催化氧化技术将在实现碳四烷烃氧化过程中发挥重要的作用。 相似文献
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合成了咪唑离子液体功能化salen Mn配合物(IL-salen Mn),并作为催化剂应用于苯乙烯与CO2一锅合成碳酸苯乙烯酯反应中.以尿素过氧化氢(UHP)为氧化剂、吡啶氮氧化物(PyNO)为助剂,催化苯乙烯高效制备环氧苯乙烷,继而催化环氧苯乙烷与CO2发生环加成反应合成碳酸苯乙烯酯.考察了催化剂种类和用量、助剂用量、氧化剂种类和用量、反应时间、反应温度及CO2压力对上述反应的影响.结果表明,当催化剂IL-salen Mn用量为苯乙烯物质的量的8%、n(苯乙烯):n(UHP):n(PyNO)=1.0:3.0:0.2、环氧化反应温度和时间分别为30℃和5 h、环加成反应温度和时间分别为80℃和12 h、CO2压力为1.0 MPa时,苯乙烯的转化率为90%,碳酸苯乙烯酯收率达到32%.结合前期研究与反应时间动力学结果,推测了该一锅反应的可能机理. 相似文献
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文章简要回顾了近年来的新型高效混凝土减水剂研究现状,阐述了包括多环芳烃、氨基磺酸、聚羧酸及改性木质素磺酸盐等几种主要类型的新型高效减水剂的合成技术、性能特点及应用现状,结合目前国内高效减水剂的研究现状,展望了高效减水剂的发展方向,认为开发减水率更高、性能更优异、经济性更好的新产品是今后高效混凝土减水剂发展的主要方向. 相似文献
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Highly efficient solvent-free coupling reaction of carbon dioxide(CO2)and epichlorohydrin catalyzed by meso-tetraphenyl porphyrin magnesium(MgTPP)in the presence of triethylamine as co-catalysts is reported.As a chlorophyll-like catalyst,MgTPP showed excellent activity for the coupling reaction of CO2 and epichlorohydrin to chloropropene carbonate,in which the turnover number could reach up to 9200.Moreover,different factors including the amount of catalyst,reaction temperature,pressure and time were systematically investigated and the optimal reaction conditions were obtained(epichlorohydrin 50 mmol,MgTPP 5.0×10- 3mmol,triethylamine 6.25×10-3 mmol,140°C,1.5 MPa,8 h).A plausible two-pathway mechanism for the coupling reaction of CO 2and epichlorohydrin is proposed to propound the catalysis of MgTPP. 相似文献
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Insoluble β-cyclodextrin polymers were prepared from β-cyclodextrin(β-CD) using epichlorohydrin(EPI) as crosslinking agent under basic conditions.The polymers were characterized by Fourier Transform Infrared(FTIR),Thermogravimetry(TG),X-ray diffraction(XRD) and TG-FTIR.The results demonstrated that the polym-erization between EPI and β-CD indeed occurred,and a number of CD rings were interconnected to form a three-dimensional network.Moreover,different factors influencing the polymerization,e.g.molar ratio of EPI to β-CD,the concentration of NaOH and reaction temperature,have been investigated.The polymer prepared under the optimal conditions(the molar ratio EPI:β-CD of 44,the NaOH concentration 50% in mass,and the temperature at 65 ℃) showed excellent thermal stability and insolubility in organic solvents or strong acid/base.In addition,the β-cyclodextrin polymers also presented high catalytic activity for aqueous oxidation of benzyl alcohol with hy-pochlorite as oxidant. 相似文献
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基于“可持续发展”和“绿色化学”的概念,近年来CO2的捕获、储存及资源化利用在工业上和学术上一直备受关注。通过具有100%原子经济性特点的CO2与环氧化物环加成反应合成五元环状碳酸酯是最有前景的方法之一。基于均相催化剂的设计思想与方法,以CO2和环氧化物的活化本质出发,从催化剂结构的角度综述了均相体系中酸碱协同催化CO2与环氧化物环加成反应合成环状碳酸酯的研究进展,包括简单二元催化体系、功能型一元催化体系和金属配合物催化体系等。 相似文献