Multi-metallic bulk catalysts and methods for synthesizing the same are provided. The multi-metallic bulk catalysts contain nickel, molybdenum tungsten, niobium, and optionally, titanium and/or copper. The catalysts are useful for hydroprocessing, particularly hydrodesulfurization and hydrodenitrogenation, of hydrocarbon feedstocks.

Multi-metallic bulk catalysts and methods for synthesizing the same are provided. The multi-metallic bulk catalysts contain nickel, molybdenum tungsten, copper, and optionally, titanium and/or niobium. The catalysts are useful for hydroprocessing, particularly hydrodesulfurization and hydrodenitrogenation, of hydrocarbon feedstocks.

Tungstated zirconium catalysts for paraffin isomerization may comprise: a mixed metal oxide that is at least partially crystalline and comprises tungsten, zirconium, and a variable oxidation state metal selected from Fe, Mn, Co, Cu, Ce, Ni, and any combination thereof. The mixed metal oxide comprises about 5 wt. % to about 25 wt. % tungsten, about 40 wt. % to about 70 wt. % zirconium, and about 0.01 wt. % to about 5 wt. % variable oxidation state metal, each based on a total mass of the mixed metal oxide. The mixed metal oxide has a total surface area of about 50 m.sup.2/g or greater as measured according to ISO 9277, and at least one of the following: an ammonia uptake of about 0.05 to about 0.3 mmol/g as measured by temperature programmed adsorption/desorption, or a collidine uptake of about 100 μmol/g or greater as measured gravimetrically.

Isomerization of normal paraffins to form branched paraffins may be complicated by significant cracking of C.sub.7+ paraffins under isomerization reaction conditions. This issue may complicate upgrading of hydrocarbon feeds having significant quantities of heavier normal paraffins. Cracking selectivity may be decreased by combining one or more naphthenic compounds with a feed mixture comprising at least one C.sub.7+ normal paraffin and/or by utilizing tungstated zirconium catalysts having decreased tungsten loading. Further, C.sub.5 and C.sub.6 normal paraffins may undergo isomerization in the presence of C.sub.7+ normal paraffins. Methods for isomerizing normal paraffins may comprise: providing a feed mixture comprising at least C.sub.5-C.sub.7 normal paraffins and lacking normal paraffins larger than C.sub.8; and contacting the feed mixture with a bifunctional mixed metal oxide catalyst under isomerization reaction conditions effective to form a product mixture comprising one or more branched paraffins formed from each of the C.sub.5-C.sub.7 normal paraffins.

Systems and methods for producing an isomerization product. One or more isomerization reactors comprising a catalyst may be used to process an isomerization feedstock comprising a primary n-paraffin reactant and hydrogen gas, and the isomerization reactor may be operated at a pressure parameter at which the partial pressure of the primary n-paraffin is within about 70% to about 130% of its equilibrium vapor pressure to isomerize the primary n-paraffin reactant.

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.

A molecular sieve has a silica/alumina molar ratio of 100-300, and has a mesopore structure. One closed hysteresis loop appears in the range of P/P.sub.0=0.4-0.99 in the low temperature nitrogen gas adsorption-desorption curve, and the starting location of the closed hysteresis loop is in the range of P/P.sub.0=0.4-0.7. The catalyst formed from the molecular sieve as a solid acid not only has a good capacity of isomerization to reduce the freezing point, but also can produce a high yield of the product with a lower pour point. The process for preparing the catalyst involves steps including crystallization, filtration, calcination, and hydrothermal treatment.

A molecular sieve has a silica/alumina molar ratio of 100-300, and has a mesopore structure. One closed hysteresis loop appears in the range of P/P.sub.0=0.4-0.99 in the low temperature nitrogen gas adsorption-desorption curve, and the starting location of the closed hysteresis loop is in the range of P/P.sub.0=0.4-0.7. The catalyst formed from the molecular sieve as a solid acid not only has a good capacity of isomerization to reduce the freezing point, but also can produce a high yield of the product with a lower pour point. The process for preparing the catalyst involves steps including crystallization, filtration, calcination, and hydrothermal treatment.

A method for activating an oxidic fresh hydroprocessing catalyst or the catalytically active material of a spent hydroprocessing catalyst comprising a refractory oxide support and one or more base metals selected from Ni, Co, Mo and W comprises optionally regenerating the catalyst, adjusting an aqueous activating solution, which contains an organic acid, to pH > 3 with an alkaline additive, impregnating the catalytically active material with the pH-adjusted aqueous activating solution, and heat-treating the catalyst at a temperature of 120-450° C.

Processes for producing olefins include passing a hydrocarbon feed to a hydrocarbon cracking unit that cracks the hydrocarbon feed to produce a cracker effluent, passing the cracker effluent to a cracker effluent separation system that separates the cracker effluent to produce at least a cracking C4 effluent including 1-butene, 1,3-butadiene, and isobutene, passing the cracking C4 effluent to an SHIU that contacts the cracking C4 effluent with hydrogen in the presence of a selective hydrogenation catalyst to produce a hydrogenation effluent having a 2-butenes concentration greater than or equal to the sum of the concentrations of 1-butene and isobutene. The processes include passing the hydrogenation effluent to a metathesis unit that contacts the hydrogenation effluent with a metathesis catalyst and a cracking catalyst downstream of the metathesis catalyst to produce a metathesis reaction effluent comprising at least propene.