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.

Layered cracking catalyst and method of manufacture and use thereof

Abstract: A layered catalyst contains a core of at least one, and preferably three, molecular sieve components within a shell layer of reduced molecular sieve content. A preferred catalyst consists of a core of a large pore molecular sieve, preferably a dealuminized Y-type zeolite, a shape selective paraffin cracking/isomerization component, preferably HZSM-5, and a shape selective aliphatic aromatization component, preferably gallium ZSM-5, within a shell of an alumina-rich, matrix. The shell can capture metals from the feeds being processed, it can act as a metals sink, and can remove metals from the unit by attrition. The catalyst is preferably prepared by forming the core and then coating or encapsulating the core with a shell having a reduced molecular sieve content. The shell may contain a pillared clay or other very large pore cracking component. The shell may be an attritable coating of an amorphous rare earth oxide, aluminum oxide and aluminum phosphate composite, which traps metals.

The Efficiency of a DTPA-Based Solvent in the Dissolution of Barium Sulfate Scale Deposits

Abstract: This paper describes kinetic experiments to determine the rate at which Ba ions are mobilized from crystalline barium sulfate into aqueous solution by a solvent in which the active ingredient is a strong chelating agent for Ba ions (DTPA -- diethylene triamine pentaacetic acid). The experiments define the temperature dependence and hence the activation energy of the dissolution process, the surface area dependence and most importantly the dependence on the concentration of the DTPA in solution. In a 0.05M DTPA solution the dissolution rate of barium sulfate is highly temperature dependent with an activation energy of {approximately}45 kJ/mol. This value suggests that the rate is controlled by the desorption of a BA-DTPA surface complex. Surface complexation is further identified as the key to barium sulfate dissolution by the observation that over the concentration range 0.5M to 0.05M DTPA the initial dissolution rate is inversely related to the DTPA concentration. The activation energy remains unaltered but the absolute dissolution rate is increased. In other words, a 0.05M DTPA solution is more efficient as a solvent than a 0.5M solution. This unexpected result is interpreted in terms of a passivation of the barium sulfate surface by the formation of a surface complexmore » layer at high DTPA concentrations.« less

Zeolite-clay composition and uses thereof

Abstract: A hydrous aluminosilicate adsorbent composition in which the active adsorbent is a mixture of non-fibrous clay with non-fibrous zeolite. The composition is useful as a feed supplement in animal husbandry, and as a topical adsorbent for veterinary use. The mixture has a high capacity for adsorption of ammonium cations, and a synergistically high selectivity for their adsorption. Beneficial effects as feed supplement may arise from lowering the amount of ammonia passed to the liver from the alimentary canal.

Integrated hydroprocessing scheme with segregated recycle

Abstract: Petroleum products are refined in an integrated hydroprocessing scheme involving a hydrocracking stage (1) and subsequent dewaxing stage (16). Materials boiling in the middle distillate or lube oil range may be dewaxed. The bottoms streams (12, 34) and optionally other streams from each stage are maintained separately from one another during processing. Dewaxing may occur using either hydroisomerization catalysts or shape-selective catalysts or both in series. One embodiment employs a baffle (14) in the flash zone of a fractionator (13) to separate bottoms streams from each other. Alternatively, the effluent (4) from the hydrocracking stage may be processed separately from the effluent (18) from the dewaxing stage. The bottoms fraction from the dewaxing stage may be recycled back to the hydrocracking stage for futher processing or used as lube base stock.

An Investigation of Wellbore Storage and Skin Effect in Unsteady Liquid Flow: II. Finite Difference Treatment

Abstract: An investigation of the effect of well bore storage and skin effect on transient flow was conducted using a finite-difference so lution to the basic partial differential equation. The concept of skin effect was· generalized to include a damaged annular region adjacent to the wellbore (a composite reservoir). The numerical solutions were compared with analytical solutions for cases with the usual steady-state skin effect. It was found that the solutions for a finite-capacity skin effect compared clos~ly with analytical solutions at short times (wellbore storage controlled) and at long times after the usual straight line was reached. For intermediate times, presence of a finite-cap acity skin effect caused· significant departures from the infinitesimal skin solutions. Two straight lines occurred on the drawdown plot for cases of large radius of damage. The first had a slope characteristic of the flow capacity of the damaged region; the second straight line had a slop e characteristic of the flow capacity of the undamaged region. Results are presented both in tabular form and as log-log plots of dimensionless pressures vs dimensionless times. The log-log plot may be used in a type-curve matching pro cedure to analyze short-time (before normal straight line) well-test data.