Synthesis Of Compound Oxides By Electrospinning And Application In Isobutane-Butene Alkylation

Zirconium oxide, tungsten oxide/zirconium oxide and molybdenum oxide/zirconiumoxide nanofibers were fabricated by sol-gel process and electrospinning technique, usingpolyvinyl alcohol (PVA Mn=80000) and various of inorganic salts as precursor. This methodoffered a brand-new way for fabricating one-dimensional inorganic nanomaterial. Then thecompound oxides solid acid acted as catalyst in isobutene-butene alkylation ,which is helpfulto develop environment friendly and easily regenerable solid catalyst.WO₃/ZrO₂ and MoO3/ZrO₂ ultra-fine fibers have been synthesized by electrospinningtechnology and structurally characterized by XRD, IR , N₂ adsorption-desorption and SEM.Thermochemical behavior and acidity were studied by TG-DTA and NH3-TPD, respectively.For comparison, WO₃/ZrO₂ and MoO₃/ZrO₂ prepared by incipient wetness impregnation andsol-gel method are investigated. It can be seen from the IR and TG-DTA spectra that PVAhave decomposed completely, the compound oxides were left. The X-ray diffraction spectraindicates that in the uncalcined samples there is interaction organic and inorganic portion,while cacined samples are crystallized. And the percentage of T-ZrO₂ is high. As shown in N₂adsorption-desorption isotherms, the surface area and pore volume of samples are highlyincreased than samples synthesized previously. According to transmission electronmicroscope (SEM), the average diameters of samples are micron degree, and which are about200～500 nm of BZr and BWZr(BMZr). The fiber diameter became smaller after calcinationsbecause of the decomposition of PVA. The acid test suggests that the acidity highly increasedafter calcinations.All samples have been tested as catalysts for production of alkylate. The conversion ofolefins over different samples is varied. The initial conversions of olefins over IM-W andIM-M are high, and then decreased rapidly. The conversions of olefins over WZO and MZOare higher than that of IM-W and IM-M respectively. The conversions of olefins over BWZRand BMZr are higher than those of others. The products over different samples are alike. Thechanging of catalysts can only vary the ratio of products. For different samples, the yields ofC8 are in the following order: IM-W>WZO> BWZR (or IM-M>MZO> BMZr). It could beattributed to the stronger acid strength and the more acid amount of BWZR (or BMZr).