The present invention discloses a composite catalyst for the photocatalytic isomerization of norbornadiene to prepare quadricyclane, comprising: a solid photocatalyst, selected from the group consisting of TiO.sub.2, Ti-MCM-41, Ti-SBA-15, ZnO, WO.sub.3, Ta.sub.2O.sub.5 or SrTiO.sub.3; and an organic photo-sensitizer loaded on the surface or in the channel of said solid photocatalyst, selected from benzophenone, acetophenone, Michler's Ketone, tetraethyl Michler's Ketone, and diethyl Michler's Ketone, where the organic photo-sensitizer is present in the solid photocatalyst in an amount of 0.5% to 20% by weight. The catalyst of the invention can catalyze a target reaction under the condition that no solvent is used, and the yield of the target product quadricyclane is higher. Furthermore, the catalyst of the invention has a stable activity, and it can be recycled. The invention further discloses a process for preparing the composite catalyst.

The present invention discloses a composite catalyst for the photocatalytic isomerization of norbornadiene to prepare quadricyclane, comprising: a solid photocatalyst, selected from the group consisting of TiO.sub.2, Ti-MCM-41, Ti-SBA-15, ZnO, WO.sub.3, Ta.sub.2O.sub.5 or SrTiO.sub.3; and an organic photo-sensitizer loaded on the surface or in the channel of said solid photocatalyst, selected from benzophenone, acetophenone, Michler's Ketone, tetraethyl Michler's Ketone, and diethyl Michler's Ketone, where the organic photo-sensitizer is present in the solid photocatalyst in an amount of 0.5% to 20% by weight. The catalyst of the invention can catalyze a target reaction under the condition that no solvent is used, and the yield of the target product quadricyclane is higher. Furthermore, the catalyst of the invention has a stable activity, and it can be recycled. The invention further discloses a process for preparing the composite catalyst.

Embodiments of a method of synthesizing a metathesis and isomerization catalyst or metathesis catalyst or isomerization catalyst comprises forming a catalyst precursor solution comprising a diluent and a catalyst precursor where the catalyst precursor comprises at least one of a silica precursor and an alumina precursor for the isomerization catalyst and additionally an oxometallate precursor or metal oxide precursor for the metathesis catalyst or the metathesis and isomerization catalyst, where the catalyst precursor solution is absent a surfactant; aerosolizing the catalyst precursor solution; drying the aerosolized catalyst precursor mixture to form a dried catalyst precursor; and reacting the dried catalyst precursor to yield the metathesis and isomerization catalyst or the metathesis catalyst or the isomerization catalyst, the metathesis and isomerization catalyst comprising a silica and alumina support with an oxometallate or a metal oxide distributed within the silica and alumina support.

The invention discloses a continuous process for producing high-pure quadricyclane, in which a reaction-rectification integral process or a reaction followed by rectification process may be employed. The two processes both use a novel composite catalyst which is obtained by loading an organic photo-sensitizer on a solid photocatalyst, and the composite catalyst has a high activity and a good stability. In the reaction-rectification integral process, the composite catalyst is used by being blended with rectification fillers or covering the rectification fillers, so as to achieve the integration of the reaction and the rectification. In the reaction followed by rectification process, the composite catalyst and the rectification fillers are placed separately from each other. The two processes achieve a relatively short residence time of reactants, produce highly-pure quadricyclane, and reduce the formation of cokes.

The invention discloses a continuous process for producing high-pure quadricyclane, in which a reaction-rectification integral process or a reaction followed by rectification process may be employed. The two processes both use a novel composite catalyst which is obtained by loading an organic photo-sensitizer on a solid photocatalyst, and the composite catalyst has a high activity and a good stability. In the reaction-rectification integral process, the composite catalyst is used by being blended with rectification fillers or covering the rectification fillers, so as to achieve the integration of the reaction and the rectification. In the reaction followed by rectification process, the composite catalyst and the rectification fillers are placed separately from each other. The two processes achieve a relatively short residence time of reactants, produce highly-pure quadricyclane, and reduce the formation of cokes.

The present disclosure relates to processes for the removal of paraffins. The processes generally include providing a C.sub.4 containing stream including isobutylene, 1-butene, 2-butene, n-butane and isobutane, introducing the C.sub.4 containing stream into a paraffin removal process to form an olefin rich stream, wherein the paraffin removal process is selected from extractive distillation utilizing a solvent including an organonitrile, passing the C.sub.4 containing stream over a semi-permeable membrane and combinations thereof; and recovering the olefin rich stream from the paraffin removal process, wherein the olefin rich stream includes less than 5 wt. % paraffins.

The present invention relates to a method for preparing an iodine-doped TiO.sub.2 nano-catalyst and use of the catalyst in heterogeneously catalyzing configuration transformation of trans-carotenoids. The iodine-doped TiO.sub.2 nano-catalyst is prepared by a sol-gel process using a titanate ester as a precursor and an iodine-containing compound as a dopant in the presence of a diluent, inhibitor and complexing agent. The catalyst exhibits high activity for isomerization of the trans-carotenoids into their cis-isomers within a short catalytic time. The catalyst can be easily prepared and is highly efficient, economical, recyclable and environmentally friendly.

The present invention relates to a method for preparing an iodine-doped TiO.sub.2 nano-catalyst and use of the catalyst in heterogeneously catalyzing configuration transformation of trans-carotenoids. The iodine-doped TiO.sub.2 nano-catalyst is prepared by a sol-gel process using a titanate ester as a precursor and an iodine-containing compound as a dopant in the presence of a diluent, inhibitor and complexing agent. The catalyst exhibits high activity for isomerization of the trans-carotenoids into their cis-isomers within a short catalytic time. The catalyst can be easily prepared and is highly efficient, economical, recyclable and environmentally friendly.

Embodiments of a method of synthesizing a metathesis and isomerization catalyst or metathesis catalyst or isomerization catalyst comprises forming a catalyst precursor solution comprising a diluent and a catalyst precursor where the catalyst precursor comprises at least one of a silica precursor and an alumina precursor for the isomerization catalyst and additionally an oxometallate precursor or metal oxide precursor for the metathesis catalyst or the metathesis and isomerization catalyst, where the catalyst precursor solution is absent a surfactant; aerosolizing the catalyst precursor solution; drying the aerosolized catalyst precursor mixture to form a dried catalyst precursor; and reacting the dried catalyst precursor to yield the metathesis and isomerization catalyst or the metathesis catalyst or the isomerization catalyst, the metathesis and isomerization catalyst comprising a silica and alumina support with an oxometallate or a metal oxide distributed within the silica and alumina support.

The present invention is related to the isomerization process in which a light naphtha stream comprising of paraffinic (mono and single branched), naphthenic and aromatic hydrocarbons in the range of C.sub.5-C.sub.7 is contacted with the solid catalyst in multiple reaction zones and in presence of hydrogen to produce high octane gasoline predominantly comprising of paraffins (single and di-branched) and naphthenes. The process scheme comprises of more than one isomerization reaction section operating at different temperatures and other operating conditions. The catalyst employed in these reaction sections is a high coordination sulfated mixed metal oxide catalyst which contains at least one noble metal and sulfated zirconia in addition to the other components. The process of the present invention also comprises more than one fractionation section and recycling of a particular stream to the reaction zone for improving the isomerization of light naphtha.