Abstract: A crystalline, gallioaluminosilicate molecular sieve having the faujasite structure is synthesized by mixing a substantially gallia-free aluminosilicate hydrogel with a galliosilicate solution substantially free of alumina to form a mixture having the following oxide mole ratios of componentsSiO.sub.2 /(Al.sub.2 O.sub.3 +Ga.sub.2 O.sub.3)=5 to 30Na.sub.2 O/(Al.sub.2 O.sub.3 +Ga.sub.2 O.sub.3)=1 to 5H.sub.2 O/(Al.sub.2 O.sub.3 +Ga.sub.2 O.sub.3)=50 to 300and then crystallizing the resultant mixture, usually in 3 days or less, under relatively quiescent conditions.
Abstract: A processing for producing silicon carbide whiskers in which a source of silica is mixed with a residual oil or crude petroleum and the resultant mixture is heated in a substantially nonoxidizing atmosphere at temperature sufficiently high to carbonize the residual oil or crude petroleum, thereby forming an intimate mixture of carbon and silica. The intimate mixture is then heated in a nonoxidizing atmosphere in the presence of a seeding component comprising an element selected from the group consisting of boron, the rare earths, Group IA, Group IB, Group VB, Group VIB, Group VIIB and Group VIII of the Periodic Table of Elements at temperatures sufficiently high to induce the reaction between carbon and silica to form silicon carbide. The resultant silicon carbide product will contain a relatively high concentration of silicon carbide whiskers.
Abstract: A crystalline, galliosilicate molecular sieve having the zeolite L type structure and the following composition expressed in terms of oxide mole ratios in the anhydrous state:Ga.sub.2 O.sub.3 :xSiO.sub.2 yM.sub.2 O:zK.sub.2 Owhere M is an alkali metal other than potassium, preferably sodium, x equals at least 3.0, preferably 4 to 10, y equals 0 to 0.9 z equals 0.1 to 1.0, and y+z equals about 1.0. The crystalline, galliosilicate molecular sieve of the invention may be employed, after reducing its alkali metal content, as a component of a catalyst which can be used in a variety of chemical conversion processes, preferably hydrocarbon conversion processes, and most preferably hydrocracking and isomerization processes.
Abstract: A composition useful for catalyzing alkylation and transalkylation reactions comprises a molecular sieve having alkylation and/or transalkylation activity, an inorganic refractory oxide component and greater than about 250 ppmw ammonium ions, calculated as (NH.sub.4).sub.2 O on a volatiles-free basis. Such a catalyst has been found to be highly selective for the production of cumene in an intergrated process in which benzene is alkylated with propylene and transalkylated with diisopropylbenzene. The catalyst can also be used to selectively produce ethylbenzene via an intergrated process in which benzene is alkylated with ethylene and transalkylated with diethylbenzene.
Abstract: A crystalline, galliosilicate molecular sieve of the zeolite omega structure and having the following composition expressed in terms of oxide mole ratios in the anhydrous state:Ga.sub.2 O.sub.3 :xSiO.sub.2 :yM.sub.2 Owhere M is an alkali metal, preferably sodium, x equals 5 to 30, preferably 5 to 15, and y equals about 1.0. The crystalline, galliosilicate molecular sieve of the invention is crystallized in the absence of a templating agent from a mixture of a substantially alumina-free hydrogel containing gallia and a substantially alumina-free galliosilicate solution. The resultant sieve may be employed, after reducing its alkali metal content, as a component of a catalyst which can be used in a variety of chemical conversion processes.
Abstract: A midbarrel hydrocracking catalyst for use in producing middle distillate products from hydrocarbon feedstocks via hydrocracking comprises at least one hydrogenation component, preferably one containing a metal selected from Group VIB and/or Group VIII of the Periodic Table of Elements, a layered magnesium silicate such as sepiolite, an intercalated clay such as pillared clay, and, optionally, a crystalline molecular sieve, preferably a zeolitic molecular sieve such as the modified Y zeolite known as LZ-10 zeolite.
Abstract: The friability of green needle coke is reduced by heating the green needle coke to a temperature between about 875.degree. F. and about 1,200.degree. F. for a time sufficient to reduce the friability of the green needle coke.
Type:
Grant
Filed:
November 22, 1988
Date of Patent:
April 16, 1991
Assignee:
Union Oil Company of California
Inventors:
Michael J. Block, Arnold E. Kelley, Milan Skripek
Abstract: A crystalline, galliosilicate molecular sieve having the zeolite L type structure and the following composition expressed in terms of oxide mole ratios in the anhydrous state:Ga.sub.2 O.sub.3 :xSiO.sub.2 :yM.sub.2 O:zK.sub.2 Owhere M is an alkali metal other than potassium, preferably sodium, x equals at least 3.0, preferably 4 to 10, y equals 0 to 0.9, z equals 0.1 to 1.0, and y+z equals about 1.0. The crystalline, galliosilicate molecular sieve of the invention may be employed, after reducing its alkali metal content, as a component of a catalyst which can be used in a variety of chemical conversion processes, preferably hydrocarbon conversion processes, and most preferably hydrocracking and isomerization processes.
Abstract: A crystalline, gallioaluminosilicate molecular sieve having the offretite structure is synthesized by mixing a substantially gallia-free aluminosilicate hydrogel containing a templating or directing agent with a galliosilicate solultion substantially free of alumina to form a mixture and then crystallizing the resultant mixture, usually in 24 hours or less.
Abstract: A hydrocarbon conversion catalyst useful for converting hydrocarbon feeds to midbarrel products is prepared by extruding a mixture of an inorganic refractory oxide component and a crystalline aluminosilicate zeolite having cracking activity to form extrudates which are broken into particles normally ranging in length between 1/16 and 1/2 inch. The extruded particles are then calcined in the presence of steam at a water vapor partial pressure greater than about 2.0 p.s.i.a., preferably greater than about 5.0 p.s.i.a. The calcination step is carried out in the presence of sufficient steam for a sufficient amount of time at a sufficient temperature to convert the crystalline aluminosilicate zeolite in the extrudates into an ultrahydrophobic zeolite having a unit cell size between about 24.20 and about 24.45 Angstroms and a sorptive capacity for water vapor less than about 5 weight percent of the zeolite at 25.degree. C. and a p/p.degree. value of 0.10.
Abstract: An attrition resistant catalytic cracking catalyst is prepared by spray drying an aqueous slurry containing a molecular sieve having cracking activity, a clay such as kaolin, a silica sol and aluminum chlorhydroxide. The resultant catalyst has a high attrition resistance as compared to commercially available cracking catalysts.
Abstract: Silicon carbide is produced by a method which includes dispersing silica in a residual oil, carbonizing the oil at elevated temperatures, and heating the carbonized dispersion to form silicon carbide. Preferably, the silica is an amorphous type. Preferred residual oils are produced by distilling away crude petroleum components at temperatures up to about 350.degree. C. The silicon carbide product typically contains a mixture of powder and whisker configurations, and has many particles with a dimension less than about 1 micrometer.
Abstract: A crystalline, galliosilicate molecular sieve having the erionite-type structure and the following composition expressed in terms of oxide mole ratios in the anhydrous state:Ga.sub.2 O.sub.3 :xSiO.sub.2 :yM.sub.2 O:zN.sub.2 O:tQ.sub.2 Owhere M is an alkali metal, preferably sodium, N is an alkali metal other than M, preferably potassium, Q is a cation derived from the templating agent used in synthesizing the galliosilicate molecular sieve, preferably a choline cation, x equals 5.5 to 30, y equals 0.1 to 0.9, z equals 0.1 to 0.9, t equals 0.1 to 0.6 and y+z+t equals about 1.0. The crystalline, galliosilicate molecular sieve of the invention may be employed, after reducing its alkali metal content, as a component of a catalyst which can be used in a variety of chemical conversion processes, preferably hydrocarbon conversion processes, and most preferably hydrodewaxing, hydrocracking and isomerization processes.
Abstract: Low speed shutdown apparatus for a high temperature hammer mill having a relatively high speed drive motor connected to the hammer mill drive shaft includes a low speed, high torque shutdown drive motor and a drive belt for connecting the low speed shutdown motor to the hammer mill shaft in place of the high speed drive motor. Preferably both the high speed drive motor and the low speed shutdown motor are connected to the hammer mill shaft through electrically controlled clutches, an electrical control being provided for disengaging the high speed drive motor in the event of a shutdown situation in which the hammer mill is shutdown while loaded with hot material and for engaging the low speed motor with the shaft to keep the shaft turning so as to prevent or substantially eliminate warping of the shaft due to the high temperature in the mill while the mill cools down.
Abstract: A crystalline, galliosilicate molecular sieve having the erionite-type structure and the following composition expressed in terms of oxide mole ratios in the anhydrous state:Ga.sub.2 O.sub.3 :xSiO.sub.2 :yM.sub.2 O:zN.sub.2 O:tQ .sub.2 Owhere M is an alkali metal, preferably sodium, N is an alkali metal other than M, preferably potassium, Q is a cation derived from the templating agent used in synthesizing the galliosilicate molecualr sieve, preferably a choline cation, x equals 5.5 to 30, y equals 0.1 to 0.9, z equals 0.1 to 0.9, t equals 0.1 to 0.6 and y+z+t equals about 1.0. The crystalline, galliosilicate molecular sieve of the invention may be employed, after reducing its alkali metal content, as a component of a catalyst which can be used in a variety of chemical conversion processes, preferably hydrocarbon conversion processes, and most preferably hydrodewaxing, hydrocracking and isomerization processes.
Abstract: A crystalline, galliosilicate molecular sieve having the zeolite L type structure and the following composition expressed in terms of oxide mole ratios in the anhydrous state:Ga.sub.2 O.sub.3 :xSiO.sub.2 :yM.sub.2 O:zK.sub.2 Owhere M is an alkali metal other than potassium, preferably sodium, x equals at least 3.0, preferably 4 to 10, y equals 0 to 0.9, z equals 0.1 to 1.0, and y+z equals about 1.0. The crystalline, galliosilicate molecular sieve of the invention may be employed, after reducing its alkali metal content, as a component of a catalyst which can be used in a variety of chemical conversion processes, preferably hydrocarbon conversion processes, and most preferably hydrocracking and isomerization processes.
Abstract: A method for inhibiting the deposition of wax in an oil well producing a wax-containing petroleum from a subterranean formation comprises injecting into the oil pool at the base of said well a copolymer comprised of ethylene and vinyl acetate and having an average molecular weight between about 15,000 and about 35,000.
Abstract: Hydrocarbon feedstocks containing relatively high levels of vanadium contaminants are converted by catalytic cracking to products of lower average molecular weight by contacting the feedstock with a catalyst comprising (1) a crystalline aluminosilicate zeolite dispersed in a matrix and (2) a vanadium passivating agent selected from the group consisting of cerium, praseodymium, neodymium, gadolinium and compounds thereof. The passivating agent is present in the catalyst in an amount greater than about 1.0 weight percent, calculated as the oxide of the vanadium passivating agent and based on the carbon-free weight of the catalyst. The passivating agent is also present in an amount such that the weight ratio of the passivating agent to any lanthanum present in the catalyst, calculated based on the respective oxides, is greater than about 1.0. The total weight of all rare earths present in the catalyst is greater than about 2.
Abstract: A process for purifying an aqueous, hydrogen sulfide-scrubbing solution which contains a water-soluble transition metal component, such as a vanadium component or an iron component, in addition to at least one water-soluble organic compound, such as an aromatic sulfonate or an alkanolamine, in which the scrubbing solution is mixed with particles of a spent solid catalyst containing molybdenum and aluminum and a basic aqueous solution, preferably a solution comprising sodium aluminate, to form a slurry which is subsequently contacted with an oxygen-containing gas under conditions such that the molybdenum in the catalyst is solubilized. Thereafter, molybdenum is precipitated from the solution along with the water-soluble transition metal component and a wastewater substantially free of the transition metal component and the organic compound originally present in the scrubbing solution is recovered.
Abstract: Hydrocarbon feedstocks containing relatively high levels of nitrogen contaminants are converted by catalytic cracking to products of lower average molecular weight by contacting the feedstock under cracking conditions with a cracking catalyst having a surface area of at least 150 m.sup.2 /gm and comprising greater than about 25 weight percent of a Y zeolite dispersed in a matrix containing a synthetic silica-alumina component in which the weight ratio of silica-to-alumina is preferably equal to or greater than about 0.10.