Showing papers by "Mobil published in 1976"

Crystalline zeolite ZSM-23 and synthesis thereof

Abstract: A new crystalline zeolite, designated ZSM-23, a method of making same and the use thereof in catalytic conversion of organic compounds is the subject of this application. The new zeolite has a composition, in the anhydrous state, expressed in terms of mole ratios of oxides, as follows; (0.58-3.4)M.sub.2/n O : Al.sub.2 O.sub.3 : (40-250)SiO.sub.2 wherein M is at least one cation having a valence n, and is characterized by a specified X-ray powder diffraction pattern.

A lumping and reaction scheme for catalytic cracking

Abstract: A predictive kinetic model has been developed for fluid catalytic cracking (FCC). The kinetic scheme involves lumped species consisting of paraffins, naphthenes, aromatic rings, and aromatic substituent groups in light and heavy fuel oil fractions. The kinetic model also incorporates the effect of nitrogen poisoning, aromatic ring adsorption, and time dependent catalyst decay. The rate constants for these lumped species are invariant with respect to charge stock composition. The predictive capabilities of the model have been verified for wide ranges of charge stocks and process conditions.

Conversion of synthesis gas to hydrocarbon mixtures

Abstract: Synthesis gas is contacted with an intimate mixture of a carbon monoxide hydrogen reduction catalyst, comprising a methanol synthesis catalyst in combination with a selective class of acidic crystalline aluminosilicate having a silica/alumina ratio greater than 12, a pore dimension greater than about 5 Angstroms to produce hydrocarbon mixtures useful in the manufacture of heating fuels, gasoline, aromatic hydrocarbons, and chemicals intermediates

Polarization in Cadmium Telluride Nuclear Radiation Detectors

Abstract: Polarization has been studied in semi-insulating cadmium telluride compensated with chlorine. Several parameters have been considered including surface preparation, nature of the contact, temperature, as well as type and strength of the source. A model that assumes that the space charge region is produced by injected electrons being trapped by deep acceptors explains most of the effects observed. The possible nature of the center is discussed. Finally it is demonstrated that MIS structures are also a practical means to suppress the polarization.

Hydraulic fracturing technique

Abstract: This specification discloses a technique of hydraulically fracturing a subterranean formation wherein there is used a fracturing fluid comprised of an aqueous solution of an interaction product of a polysaccharide and a galactomannan.

Conversion of methanol to gasoline components

Abstract: A method and sequence of process steps is described for effecting the conversion of lower alcohols comprising methanol, ethanol and propanol to gasoline boiling range component arranged to significantly extract reaction heat and selectively control the restricting of the alcohol feed through the production of ethers and olefins prior to isomerizing and aromatizing the formed olefins. A tubular reactor section is particularly relied upon for the highly exothermic olefin forming step of the combination operation.

Conversion of methanol to gasoline product

Abstract: The conversion of methanol to gasoline boiling products in a plurality of sequentially arranged catalyst beds comprising a dehydration catalyst followed by a special class of crystalline zeolite conversion catalyst is described wherein the dehydration catalyst life is prolonged and durene formed in the process is recycled to the zeolite catalyst conversion step.

Advanced control practice in the chemical process industry: A view from industry

Abstract: This paper presents a commentary on the status of application of modern control theories to industrial chemical processes. The difficulties encountered in the implementation of advanced control to chemical reactors are critically examined in order to determine the reasons for its limited success to date. Chemical processes, very often poorly understood because of the physicochemical complexities, are nonlinear, highly interacting, spacially dependent, and continuously disturbed by many uncharacterized noises. It is time-consuming and expensive to develop advanced control methods for these systems because few of the available theories can be applied directly. Thus, we often find it difficult to economically justify advanced control projects.

ZSM-5 containing aluminum-free shells on its surface

Abstract: Aluminosilicate zeolites are prepared containing an outer aluminum-free shell. The outer shell is essentially SiO 2 that has crystallized on the zeolite surface in the ZSM-5 type configuration, leading to a more selective catalyst.

Silica-modified zeolite catalyst and conversion therewith

Abstract: A catalyst is provided, which is especially applicable for the selective production of C 2 -C 3 olefins, comprising a crystalline aluminosilicate zeolite having a silica to alumina ratio of at least about 12, a constraint index, as hereinafter defined, within the approximate range of 1 to 12 and having contained within the interior crystalline structure thereof added amorphous silica in an amount of at least about 0.3 and preferably between about 0.5 and about 30 weight percent. The resultant catalyst is characterized by n-hexane sorption capacity at a temperature of 90° C and a n-hexane partial pressure of 83 mm. of mercury which is at least 1 percent less than corresponding sorption capacity under identical conditions for the unmodified zeolite. Generally, the n-hexane sorption capacity for the described silica-modified zeolite, at the above specified conditions, is 5 to 60 percent less than that for the zeolite which has not undergone treatment to incorporate amorphous silica therein. The invention described herein also encompasses synthesis of the specified catalyst and use of the same in selectively converting lower monohydric alcohols and their ethers, especially methanol and dimethyl ether, to a hydrocarbon mixture rich in ethylene and propylene.

Manufacture of hydrocarbons

Abstract: A catalytic process is provided for converting lower monohydric alcohols and their ethers, especially methanol and dimethyl ether, to a hydrocarbon mixture rich in C 2 -C 3 olefins and mononuclear aromatics with high selectivity for para-xylene production by contact, under conversion conditions, with a catalyst bed comprising a major proportion of particle-form inert solid diluent having intermixed therewith a crystalline aluminosilicate zeolite characterized by (1) a crystallite size not greater than 0.5 micron, (2) a particle size less than 2 millimeters in its smallest cross-sectional dimension, (3) a silica to alumina ratio of at least about 12 and (4) a constraint index, as hereinafter defined, within the approximate range of 1 to 12.

Zeolite catalyst containing oxide of boron or magnesium

Abstract: A catalytic process is provided for converting lower monohydric alcohols and their ethers, especially methanol and dimethyl ethers, to a hydrocarbon mixture rich in C 2 -C 3 olefins and mononuclear aromatics with high selectivity for para-xylene production by contact, under conversion conditions, with a catalyst comprising a crystalline aluminosilicate zeolite, said zeolite having a silica to alumina ratio of at least about 12 and a constraint index, as hereinafter defined, within the approximate range of 1 to 12, said catalyst having been modified by the addition thereto of a minor proportion of an oxide of boron or magnesium either alone or in combination, or in further combination with an oxide of phosphorus

Manufacture of light olefins

Abstract: A catalytic process is provided for converting a charge consisting essentially of methanol, dimethyl ether or mixtures thereof to a hydrocarbon product rich in ethylene and propylene by contact, under conversion conditions, with a catalyst comprising the crystalline aluminosilicate zeolite designated "ZSM-34".

Radiation curable coating

Abstract: A radiation curable coating composition for various substrates contains an adduct of acrylic acid and an epoxy resin (which may be modified with an anhydride, such as maleic anhydride), and a reactive acrylate monomer vehicle. The coating composition can be pigmented and can also contain additives commonly used in coatings, such as wetting agents and flow control agents. The coating composition does not require the usual hydrocarbon vehicles that give rise to air pollution problems. Surface gloss of a UV cured film obtained from a pigmented coating composition can be increased by using a photosensitizer combination of 2-chlorothioxanthone and a phenylketone, such as benzophenone. Adhesion of a cured coating is improved by replacing the tertiary amine co-sensitizer, at least in part, with dimethylaminoethyl acrylate.

Selective ethylation of mono alkyl benzenes

Abstract: A catalytic process is provided for the ethylation of a mono alkyl benzene wherein the alkyl substituent contains 1 or 2 carbon atoms, i.e. toluene or ethylbenzene, to selectively produce the para ethyl derivative thereof, i.e. para ethyltoluene or para diethylbenzene by contacting said mono alkyl benzene, under conversion conditions, with an ethylating agent in the presence of a catalyst comprising a crystalline aluminosilicate zeolite, which zeolite is characterized by an activity, in terms of alpha value, of between about 2 and about 5000, and preferably between about 20 and about 500, a xylene sorption capacity greater than 1 gram/100 grams of zeolite and an ortho xylene sorption time for 30 percent of said capacity of greater than 10 minutes, said sorption capacity and sorption time being measured at 120° C. and a xylene pressure of 4.5 ± 0.8 mm. of mercury, said catalyst comprising a crystalline aluminosilicate zeolite having a silica to alumina ratio of at least about 12 and a constraint index, as hereinafter defined, within the approximate range of 1 to 12 to yield a resulting product in which the para ethyl derivative of said mono alkyl benzene is present in an amount greater than the thermodynamic equilibrium concentration thereof in the total dialkyl substituted benzenes produced.

Crystalline zeolite ZSM-34 and method of preparing the same

Abstract: A crystalline zeolite, designated ZSM-34, having the composition as synthesized and in anhydrous form, expressed as mole ratios of oxides as follows: (0.5-1.3)R2 O: (0-0.15)Na2 O: (0.10-0.50)K2 O: Al2 O3 : XSiO2 where R is the organic nitrogen-containing cation derived from choline [(CH3)3 NCH2 CH2 OH] and X is 8 to 50, said zeolite having an X-ray diffraction pattern, identifying it as a member of the offretite-erionite family and the ability, after calcination at 1000° F for at least a period of time to remove the organic cation, to sorb at least 9.5 weight percent of n-hexane at ambient temperature and a n-hexane pressure of 20mm. Organic compound conversion is carried out in the presence of a catalytically-active form of said zeolite.

Upgrading of olefinic gasoline with hydrogen contributors

Abstract: A method for upgrading poor quality olefinic gasoline by conversion thereof in the presence of carbon hydrogen-contributing fragments such as methanol and a crystalline zeolite catalyst composition of desired selectivity characteristics is described

Heat sealable thermoplastic films

Abstract: A coating composition to improve the physical characteristics of thermoplastic films, such as oriented polypropylene, comprising (1) an acrylic terpolymer of methyl methacrylate, methyl acrylate, and methacrylic acid; and (2) an aqueous-alkali soluble rosin, comprising an adduct of rosin with an alpha-beta unsaturated dicarboxylic acid esterified with a polyhydric alcohol.

Manufacture of light olefins

Abstract: A catalytic process is provided for converting a charge consisting essentially of methanol, dimethyl ether or mixtures thereof to a hydrocarbon product rich in ethylene and propylene by contact, under conversion conditions, with a catalyst comprising a crystalline aluminosilicate zeolite characterized by pores, the major dimension of which is less than 6 Angstroms and the capability, under said conditions, of producing less than 20 weight percent methane in said hydrocarbon product.

Ultra high silicon-content zeolites and preparation thereof

Abstract: A method is provided for obtaining crystalline dealuminized products by treating a slurry of a crystalline aluminosilicate zeolite in an aqueous solution of an ammonium or alkali metal salt which upon acidification yields an anion which complexes with aluminum by adding to said slurry a water-soluble acid having a first ionization constant greater than 10 -2 at a rate such that a controlled amount of aluminum is removed from the zeolite to yield a resulting product from which at least about 10% and as much as about 85% of the initial aluminum has been removed while retaining more than 60% of the original crystallinity.

Liquefaction of solid carbonaceous materials

Abstract: This invention provides a method for solubilizing wood or wood and coal mixtures in a highly aromatic refinery petroleum solvent to produce homogeneous compositions which have a flowable pitch-like consistency at ambient temperatures. The invention compositions are directly applicable as liquid fuels, or can be further processed into other desirable products.

Use of Short Term Multiple Rate Flow Tests To Predict Performance of Wells Having Turbulence

Abstract: A method is presented for predicting well performance and analyzing completion and fracture effectiveness. The new procedure uses production tests, rather than buildup tests, to determine whether turbulence is a major factor in reducing a well's flow capacity. If the pressure drop from turbulent flow is greater than expected, the well probably has an inefficient completion. For a perforated completion, this may mean too few open perforations; for a fractured well, it may indicate that the fracture is too narrow. The analysis procedure is applicable to most gas wells and to oil wells with high flow rates. Field cases are shown for two gas wells and one high-rate oil well.

Aromatization of ethane

Abstract: A catalytic process is provided for converting gaseous paraffinic feedstocks containing ethane to liquid aromatics by contacting said gaseous feeds, in the absence of added air or oxygen, under conversion conditions, with a crystalline aluminosilicate zeolite catalyst having incorporated therein a minor amount of a metal selected from Groups VIII, IIB and IB of the Periodic Table and mixtures thereof thereby converting ethane in said feed to aromatics and recovering said aromatics as liquids.

Directed crystallization of synthetic aluminosilicates

Abstract: Synthetic crystalline aluminosilicate zeolites are crystallized from an aqueous reaction mixture comprising sources of alkali metal oxide, silicate, aluminate and an ionene or ionomer which contains positively charged nitrogen atoms in such quantity as to satisfy some of the cationic sites of the eventual zeolite. The presence in the reaction mixture of such a polymer serves to direct crystallization of the zeolite, giving rise to the formation of large pore zeolites under conditions where small pore zeolites would otherwise result, to the formation of more siliceous zeolite than would otherwise result, and to the formation of certain species of zeolite essentially free of stacking faults, the crystallization of which has not heretofore been possible.

Disproportionation of toluene

Abstract: Disproportionation of toluene with high conversion thereof to produce benzene and xylenes rich in the para isomer is accomplished by subjecting toluene to disproportionation conditions in the presence of a catalyst comprising a crystalline aluminosilicate zeolite, said zeolite having a silica to alumina ratio of at least about 12 and a constraint index, as hereinafter defined, within the approximate range of 1 to 12, which catalyst has undergone prior modification by treatment with an ammonium hydrogen phosphate to deposit at least about 0.5 weight percent of phosphorus thereon.

Conversion of methanol to olefinic components

Abstract: A method and sequence of process steps is described for effecting the conversion of lower alcohols comprising methanol, ethanol, and propanol to primarily olefin boiling range component under conditions to significantly extract reaction heat and selectively control the restructuring of the alcohol feed through the production of ethers and particularly olefins.

Flexible plastic foam

Abstract: A flexible and foldable foam plastic sheet and a process for making same, said process comprising initially compressing the foam sheet between two surfaces at least one of which is a textured surface (e.g., screen like) to reduce the sheet in thickness and reduce or destroy the resilience of the foam, and then, when further reduction in thickness of the resulting sheet is desired, pressing the resulting compressed sheet between two substantially smooth surfaces to achieve such desired further reduction in thickness. Mechanical properties of the foam sheet so processed are desirably increased thereby producing a foam sheet product suitable as a replacement for paper in many applications.

Method and means for separating gasiform materials from finely divided catalyst particles

Abstract: Catalyst and hydrocarbon vapors are separated in a cyclone attached to the discharge of a riser cracking operation. The cyclone is modified to include a separate cyclonic stripping of catalyst separated from hydrocarbon vapors.

Use of short-term, multiple-rate flow tests to predict performance of wells having turbulence

Abstract: The analysis procedure presented allows prediction of well performance and diagnosis of many well completion problems with inexpensive short-term tests The procedure is particularly applicable to gas wells in good formations where completion problems are apt to occur The results allow separation of mechanical problems, such as too few open perforations or too narrow fractures, from formation damage or low permeability This permits the engineer to choose the type of stimulation or workover most likely to solve the existing problem The ability to pinpoint reasons for low productivity should make the test procedure a valuable new engineering tool (10 refs)

Reinforced thin wall plastic bag, and method and apparatus to make material for such bags

Abstract: A plastic bag such as trash can liners, grass and leaf bags, sandwich bags and the like is reinforced by placing spaced ribs therein, integral with the wall structure, the ribs having a rib-to-rib spacing in the order of 1/8 to 2 cm, the ribs being peaked and merging smoothly from a projecting peak to the thickness of the walls between the ribs, the peaks extending about 1.5 to 10 times the wall thickness of the film which is preferably, in the order of about 0.4 to 2.0 mils. Upon extrusion, the extrusion die is formed with small notches with rounded corners so that the ribs are extruded while the film material is extruded, and provide additional material in the region of the ribs which merges smoothly with the material being extruded to form the film. Such rib-reinforced bag structures may be produced by forming a continuous roll of such bags, the individual bags in such a roll being readily separated along predetermined lines of weakness.