Abstract: Hydrogen sulfide is removed from gas streams containing it with or without carbon dioxide by contacting the gas feed stream with an aqueous liquid containing sulfide and bisulfide ions and having a pH in the range from 9 to 12 to remove a minor portion of the hydrogen sulfide and then removing the remainder with an aqueous liquid containing sulfide and bisulfide ions having a higher pH in the range from 11 to 13.5.
Type:
Grant
Filed:
March 11, 1985
Date of Patent:
April 29, 1986
Assignee:
The Dow Chemical Company
Inventors:
Van A. Kent, Roberto A. Abib, Larry H. Kirby
Abstract: A process for the preparation of crystalline sodium silicates with a molar ratio SiO.sub.2 /Na.sub.2 O of 1.9:1 to 3.5:1 from amorphous sodium silicate is described. To water-containing amorphous sodium silicate with a molar ratio SiO.sub.2 /Na.sub.2 O of 1.7:1 to 3.75:1 and a water content of 5 to 95% by weight is added 0.01 to 30 parts by weight of the crystalline sodium silicate to be prepared (per 100 parts by weight of Na.sub.2 O+SiO.sub.2 in the water-containing amorphous sodium silicate).The reaction mixture is dehydrated by heating. The dehydrated reaction mixture is kept at a temperature of at least 450.degree. C., but below the melting point, until the sodium silicate has crystallized.
Abstract: A catalyst is provided which comprises a crystalline zeolite, discrete particles of phosphorus-containing alumina dispersed in a non-zeolitic inorganic oxide matrix. A catalytic cracking process utilizing the catalyst is also provided.
Abstract: In a preferred embodiment, a portable ophthalmoscope having low-power telescope elements and having an internal source of viewed-field illumination, relies on a patient's focusing properties to inspect the fundus of the eye. A laser-beam source is flexibly coupled to the patient end of the ophthalmoscope viewing axis and, after optical expansion and collimation, is folded into coincidence with the ophthalmoscope axis. A dichroic (filter) is the mirror via which the folding takes place, the filter being selected for a very narrowly limited spectral band of great attenuation of radiation at the characteristic wavelength of the involved laser, the latter having been selected for its photocoagulating and/or photoablating action on locally afflicted tissues of the retinal, choroid and/or other internal regions of the eye.
Abstract: Compositions of matter, including: A mixture of at least one oxide of manganese and at least one oxide of a Lanthanum Series metal, preferably lanthanum or cerium, or at least one oxide of niobium. The above compositions are particularly useful as catalytic compositions for the conversion of C.sub.3 and C.sub.4 hydrocarbons to less saturated hydrocarbons, particularly ethylene and propylene and preferably ethylene. The life of the catalyst for the selective production of ethylene is extended by carrying out the reaction in the presence of steam. The steam substantially increases the active life of the catalytic composition, before regeneration is necessary, as well as significantly increasing the selectivity to ethylene. Limiting the amount of "bound" or "fixed" sulfur in the catalytic composition also improves the catalyst.
Abstract: A fixed bed catalytic reactor having a porous bed of catalyst particles contained in a closed reactor shell, comprisinginlet means for introducing a downwardly flowing mixed stream of gas and liquid reactants;phase separator means for receiving said mixed stream and directing liquid onto the porous catalyst bed, said separator means being disposed within the reactor shell between said inlet means and said porous catalytic bed;said separator means comprising an upper foraminous wall having a series of gas outlets permitting a substantially-gaseous phase to escape outwardly from the separator means into an upper reactor portion, and lower liquid distribution means for receiving a stream of substantially liquid phase and dividing said liquid phase into a plurality of spaced-apart liquid streams directed toward the porous catalyst bed; andmeans for recovering gaseous and liquid reaction products from the reactor shell.
Abstract: Finely divided coal is reacted in a combination of processes comprising flash pyrolysis and fluidized bed gasification of char from the pyrolysis. A portion of the char which is heated by the steam-oxygen gasification provides the heat for the pyrolysis step, which can be controlled to emphasize production of such materials as light olefins and BTX pyrolyzing at lower pressure and more severe temperature, or to emphasize production of a tar, suitable for processing as a synthetic crude oil, by pyrolyzing at higher pressure and less severe temperature. In either instance the fluidized bed gasification produces a useful synthesis gas.
Abstract: A surgical instrument for ligating and cutting body tissue restrained in the instrument is disclosed. To ligate the tissue, the instrument applies a pair of plastic clips at spaced apart locations on the tissue. The clips are advanced towards the tissue and separated from a pair of clip trains by a clip pusher mechanism operating over a predetermined path. A knife operating over another predetermined path then cuts the tissue between the spaced apart clips. A safety mechanism is actuated by the clip pusher mechanism in the event that a clip is not presented to the pusher mechanism. The safety mechanism, when actuated by the pusher mechanism, directly blocks the path of the knife. A latch mechanism is provided which locks tissue in the instrument to alert the surgeon that the pusher mechanism has jammed at the completion of a ligating and cutting operation.
Abstract: An apparatus and method for mixing a fluidized solid and a fluid wherein the fluidized solid flows in a space defined between an outer member and an inner member positioned within the outer member. A body means is provided in the space between the members to occupy a predetermined volume in the space. A stream of solid particles flows around the body, and is directed across the upper end of the inner member. Fluid is released at the upper end of the inner member which mixes with the fluidized solid.
Abstract: Fouling of tubes carrying refinery and petrochemical process streams, especially at high operating temperatures, is reduced by introducing aluminum stearate or aluminum acetate into the stream.
Type:
Grant
Filed:
July 5, 1985
Date of Patent:
March 11, 1986
Assignee:
Exxon Research & Engineering Co.
Inventors:
Vincenzo M. P. Pizzoni, Sukhjit S. Randhawa
Abstract: Disclosed is a method and apparatus for fluid catalytic cracking (FCC) of a hydrocarbon feed in an open or closed system, which includes a multistage stripper system. The multistage stripper system comprises a means for spinning a gasiform mixture of catalyst and cracked hydrocarbons exiting from a riser, a first means for stripping the spun gasiform mixture, and a means for deflecting the gasiform mixture to separate catalyst from the cracked hydrocarbons.
Abstract: A surgical needle holder is provided in which the handle members are arranged in a plane at right angles to associated jaws which are operated by the handles. A camming arrangement is coupled between the handles and jaws to convert the movement of the handles in one plane to movement of the jaws in a second perpendicularly arranged plane. The needle holder is employed for suturing in surgical procedures and facilitates placement of the hand of the operator as well as the application of force in a rotary sense thereby.
Abstract: A combination process is described for upgrading residual oils and high boiling portions thereof comprising metal contaminants and high boiling Conradson carbon forming compounds comprising a thermal visbreaking operation with fluidizable inert solids followed by a fluidized zeolite catalytic cracking operation processing demetallized products of the visbreaking operation, regenerating solid particulate of each operation under conditions to provide CO rich flue gases relied upon to generate steam used in each of the fluidized solids conversion operation and downstream product separation arrangements, separating the wet gas product stream of each operation in a common product recovery arrangement and processing the high boiling feed product of visbreaking comprising up to 100 ppm Ni+V metal contaminant over a recycled crystalline zeolite cracking catalyst distributed in a sorbent matrix material comprising a high level of Ni+V metal contaminant.
Type:
Grant
Filed:
August 19, 1983
Date of Patent:
February 11, 1986
Assignee:
Ashland Oil, Inc.
Inventors:
Lloyd E. Busch, Paul W. Walters, Oliver J. Zandona
Abstract: A catalyst is provided which comprises a crystalline zeolite, discrete particles of phosphorus-containing alumina dispersed in a non-zeolitic inorganic oxide matrix. A catalytic cracking process utilizing the catalyst is also provided.
Abstract: A catalyst is prepared by adding a water soluble aliphatic polyhydroxy compound such as a polyhydroxy alcohol or a carbohydrate (e.g., sucrose) to an aqueous solution of chromic acid and subsequently introducing the resulting mixture into a hydrocarbon material. The hydrocarbon-containing mixture is heated in the presence of hydrogen sulfide to convert the chromium catalyst precursor to a solid chromimum-containing catalyst. Hydroconversion processes utilizing the catalyst to convert oil, coal, and mixtures thereof are also provided.
Abstract: In a crude oil refining process, heavy cycle oil from the catalytic cracking unit employed in the crude oil refining process is recycled to a hydrofining process. Such recycling improves the value of the product mix obtained from the crude oil refining process with respect to a process in which the heavy cycle oil withdrawn from the catalytic cracking units is recycled to the catalytic cracking units.
Type:
Grant
Filed:
May 25, 1984
Date of Patent:
January 21, 1986
Assignee:
Phillips Petroleum Company
Inventors:
Dean P. Montgomery, James W. Gall, Ed D. Davis
Abstract: An aiming beam coincident with a laser beam is provided in a modified slit-lamp apparatus. The aiming beam is resolved into a number of images displaced with respect to the axis of the slit lamp imaging rays bracketing the intersection of the laser beam and the axis of slit lamp rays, which intersection is their common focus. As the common focus is moved close to a target tissue within the eye, the target tissue to be treated renders each of the images successively sharply visible while the other images remain blurry or not visible. Thus an efficient rough or long-range system is provided for focusing the laser on the target tissue.
Abstract: Hot, coarse, particles removed from a retort, preferably coarse particles of oil shale removed from a retort operating at superatmospheric pressure, are crushed to a size suitable for fluidization and then fed to a fluidization zone maintained under non-oxidizing conditions at substantially the pressure of the retort to forestall escape of retort gases. Raw fines are introduced into the fluidization zone and retorted without agglomeration using heat transferred from the hot retorted particles. Also introduced into the fluidization zone is a heated fluidizing gas stream comprised of recycle retort gas, which is employed to educe hydrocarbonaceous vapors from the fines and, optionally transfer heat. Educed vapors from the fluidization zone are recycled to the retort to be partially condensed and recovered as liquid and gaseous product streams along with other vapors educed in the retort.