Mobil

About: Mobil is a based out in . It is known for research contribution in the topics: Catalysis & Zeolite. The organization has 7085 authors who have published 10642 publications receiving 237497 citations. The organization is also known as: Socony-Vacuum Oil Company & Standard Oil Company of New York.

Cracking catalysts containing phosphate treated zeolites, and method of preparing the same

Abstract: A process for preparing a zeolite containing catalyst which has improved attrition resistance, and causes improved octane with no appreciable change in dry gas and coke make when used during catalytic cracking processes is disclosed The catalyst is prepared by modifying the zeolite with a phosphate containing solution The zeolite preferably includes an REY large pore zeolite Treatment of the zeolite is best accomplished in an aqueous solution, at a pH range from about 2 to about 6, containing a water soluble phosphate compound The phosphate treatment of the zeolite is carried out by deagglomerating the zeolite in an aqueous mixture in the presence of an aqueous phosphate containing solution, such as an aqueous solution of ammonium monohydrogen phosphate The aqueous mixture containing phosphate modified zeolite is then combined with matrix precursors to form a slurry The slurry is preferably spray dried to form the catalyst having a diameter less than 200 microns The novel catalyst is used in the catalytic cracking of hydrocarbons in an FCC, moving bed or other catalytic cracking apparatus The catalyst can be used for treating resids in which the hydrocarbon feedstock has a higher average molecular weight, a lower API gravity and/or a higher metals content than gas oil

Solid elastomeric block copolymers

Abstract: There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are each a polymer (I polymer) of at least one conjugated diene (I), e.g., isoprene, which contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms; at least one middle or interior block is a hydrogenated polybutadiene (B polymer); and at least one middle or interior block is an essentially straight chain polyethylene (E polymer) resulting from the hydrogenation of a polybutadiene composed of at least 80 % of 1,4- units; or 2) the terminal blocks are random copolymers resulting from the hydrogenation of a copolymer of at least one diene I as previously defined and hydrogenated butadiene, and at least one middle or interior block is a straight chain polyethylene (E polymer) as previously defined. The hydrogenated butadiene units in the B polymer or random IB polymer blocks are composed of no more than about 65 % of 1,4- units and at least about 35 % of 1,2- units. The foregoing block copolymers may be prepared by selectively hydrogenating substantially all the butadiene units of a precursor block, copolymer wherein the precursor blocks of the straight chain polyethylene block units are polybutadiene blocks in which at least about 80 % of the butadiene units are 1,4- units. A sufficient number of I units in the I polymer blocks or random IB copolymer blocks retain their unsaturation on selective hydrogenation to enable the vulcanization of the block copolymer.

Robustness optimization for constrained nonlinear programming problems

Abstract: In realistic situations engineering designs should take into consideration random aberrations from the stipulated design variables arising from manufacturing variability. Moreover, many environmental parameters are often stochastic in nature. Traditional nonlinear optimization attempts to find a deterministic optimum of a cost function and does not take into account the effect of these random variations on the objective. This paper attempts to devise a technique for finding optima of constrained nonlinear functions that are robust with respect to such variations. The expectation of the function over a domain of aberrations in the parameters is taken as a measure of ‘robustness’ of the function value at a point. It is pointed out that robustness optimization is ideally an attempt to trade off between ‘optimality’ and ‘robustness’. A newly-developed multi-criteria optimization technique known as Normal-Boundary Intersection is used to find evenly-spaced points on the Pareto curve for the ‘optimality’ and ‘r...

Method for enhancement of sequential hydraulic fracturing using control pulse fracturing

Abstract: A method for fracturing a subterranean formation containing desired natural resources in which controlled pulse fracturing (CPF) is combined with hydraulic fracturing in a second wellbore along with hydraulic fracturing in a first wellbore. Multiple radial vertical fractures are created by CPF in the second wellbore by a solidifiable gel material which is directed into created fractures during a subsequent hydraulic fracturing procedure. During this procedure, multiple vertical hydraulic fractures initiate in and propagate away from CPF created fractures thereby bringing the second wellbore fracture system into fluid communication with the fracture system of the first wellbore.

Mixed Finite Element Method for Miscible Displacement Problems in Porous Media

Abstract: Effective numerical simulation of many EOR problems requires very accurate approximation of the Darcy velocities of the respective fluids. In this paper the authors describe a new method for the accurate determination of the Darcy velocity of the total fluid in the miscible displacement of one incompressible fluid by another in a porous medium. The new mixed finite-element procedure solves for both the pressure and velocity of the total fluid simultaneously as a system of first-order partial differential equations. By solving for u=(-K/..mu..) p as one term, we minimize the difficulties occurring in standard methods caused by differentiation or differencing of p and multiplication by rough coefficients k/..mu... By using mixed finite elements for the pressure equation coupled in a sequential method with a finite element procedure for the concentration of the invading fluid, we are able to treat a variety of problems with variable permeabilities, different mobility ratios, and a fairly general location of injection and production wells. Mixed finite-element methods also produce minimal grid-orientation effect. Computational results on a variety of two-dimensional (2D) problems are presented.