Studies On The Synthesis Of Trimethylolpropane Trioleate（TMPTO）with Solid Superacid SO4_<sup>2-/TiO₂and Performance Of TMPTO

Trimethylolpropane oleate (Abbreviation TMPTO, formula CH3CH2C(CH2OOCC17H33)3) is an important chemically modified products of vegetable oils. It has good stability of antioxidant activity and anti-elimination reaction, owing to no hydrogen on the β carbon atom in its molecule.In this paper, TMPTO was obtained by directly esterification with trimethylolpropane and oleic acid of renewable resource, which provided the basis for further preparation of the green lubricants.SO42-/MxOy has several advantages such as easy separation from reaction system、good reusability、high selectivity、good thermal stability、 non-corrosion to the reactor and environmental friendly.SO42-/TiO2solid super acid catalysts was prepared from TiO2and H2SO4, the acid strength of the SO42-/TiO2solid super acid catalysts was determined by Hammett indicators, the structure of solid super acid has been characterized by SEM and FT-IR techniques. The influence of impregnated concentration of H2SO4、impregnated time of H2SO4、the calcination time、calcination temperature on the catalytic properties were investigated, the optimal preparation conditions of SO42-/TiO2catalyst was determined, and the optimal reaction conditions was obtained. The performance of the TMPTO such as color、acid value、pour poin、water content、flash point and the thermal stability of TMPTO was analyzed by TG were tested. The results are as follows:(1) The results of Hammett indicator method showed that SO42-/TiO2acid has reach the strength of super acid. The structure characterization of SO42-/TiO2by SEM and FT-IR implied it possess good catalytic activity.(2) The catalytic activity of SO42-/TiO2on the synthetic TMPTO is higher when the H2SO4impregnation concentration1.5mol/L、H2SO4impregnation time4h and calcination for5h at temperature600℃.(3) The optimum conditions of synthesized TMPTO were reaction time6h、temperature150℃、n(oleic acid)/n(trimethylolpropane)3.2:1、 amount of SO42-/TiO22.0%, the conversion rate of trimethylolpropane was92.2%. The structure of product was identified by FT-IR. The averaged reaction rate was90.8%when SO42-/TiO2was repeatedly used three times.(4) Test results demonstrated the performance of the TMPTO such as color、acid value、pour poin、water content、flash point can meet the standards of quality. Thermogravimetric analysis results proved the good thermal stability of TMPTO.