The Study Of Polymerization And Inhibition On Styrene And Mixed C₃ & C₄ Olefin And The Study Of Dehydrogenation Catalyst Of Isobutane

The structure and the active ingredient of 11 polymerization inhibitor commonly used in industrial olefin system were be studied with infrared spectroscopy (FT-IR), nuclear magnetic resonance (1HNMR and 13CNMR), GC-MS. The structure of 4 kinds of inhibitors which have only single-component molecular was determined,and the structures information including active ingredients and effective initial inferred functional groups of the other 7 types of inhibitor samples which are complex were investigated also.We proposed the inhibition mechanism of the inhibitor with functional groups such as nitro (-NO2), hydroxy (mainly phenolic hydroxy-Ph-OH), amino (-NH2), aromatic structures (benzene or naphthalene ring) respectively.It was pointed out that active hydrogen (including alcohol hydroxyl, phenolic hydroxyl, amino, etc.), nitro and aromatic structures of inhibitor are the role active functional groups. We Choose 2 kinds of olefin polymerization system which are, to evaluate the 11 industrial inhibitor using simulation methods and designed reactor by self. According to the evaluation results with two different systems, inhibition effect were given sort out respectively.We found that the effect of inhibitor was in consistent basically to the functional groups contained and the effect was superior in styrene than in mixed c3-c4 generally. As a sequence by combining the performance evaluation and the research of functional groups and effective ingredients of inhibitor, we concluded that a high efficient inhibitor should have the active hydrogen (including alcohol hydroxyl, phenolic hydroxyl, amino, etc.), nitro, aromatic structure (including benzene, naphthalene ring structure) and other functional groups. Structure and properties study of inhibitors demonst that hydroxyl hydrogen is more active than amino hydrogen, that the more phenolic hydroxyl number in inhibitor molecule, the better,and that the nitrate phenol-type inhibitors containing nitro, hydroxyl, aromatic structure togather are the most significant.The catalytic dehydrogenation catalyst of isobutane was studied. That was focus on the catalytic system containing metal oxide from the groupⅧB.The other elements were introduced into catalyst to modulate catalytic performance. XRD, SEM were used to characterize the crystal and morphology of catalyst samples. We evaluate the performance of dehydrogenation catalysts by a fixed-bed reactor with the industrial isobutane as raw material. The reaction results showed that the catalyst with Fe2O3·K2O has higher activity and selectivity, that is, the conversions of isobutane reach 85.8% and the selectivities to isobutylene reach 55.2%.So we preliminarily determine the researching direction of new non- noble-metal catalyst of isobutane dehydrogenation.