Showing papers on "Aromatic hydrocarbon published in 1989"

Oxidation of aromatic contaminants coupled to microbial iron reduction

Abstract: THE contamination of sub-surface water supplies with aromatic compounds is a significant environmental concern1,2. As these contaminated sub-surface environments are generally anaerobic, the microbial oxidation of aromatic compounds coupled to nitrate reduction, sulphate reduction and methane production has been studied intensively1–7. In addition, geochemical evidence suggests that Fe(III) can be an important electron acceptor for the oxidation of aromatic compounds in anaerobic groundwater. Until now, only abiological mechanisms for the oxidation of aromatic compounds with Fe(III) have been reported8–12. Here we show that in aquatic sediments, microbial activity is necessary for the oxidation of model aromatic compounds coupled to Fe(III) reduction. Furthermore, a pure culture of the Fe(III)-reducing bacterium GS-15 can obtain energy for growth by oxidizing benzoate, toluene, phenol or p-cresol with Fe(III) as the sole electron acceptor. These results extend the known physiological capabilities of Fe(III)-reducing organisms and provide the first example of an organism of any type which can oxidize an aromatic hydrocarbon anaerobically.

Liquid phase alkylation or transalkylation process using zeolite beta

Abstract: A process for the alkylation or transalkylation of an aromatic hydrocarbon which comprises contacting the aromatic hydrocarbon with a C2 to C4 olefin alkylating agent or a polyalkyl aromatic hydrocarbon transalkylating agent, under at least partial liquid phase conditions, and in the presence of a catalyst comprising zeolite beta.

Substituted cyclodextrins and process for chromatographic separation of chiral organic compounds.

Abstract: Substituted cylodextrins of general formula (I), where R2 and R6 are linear-chain or branched-chain alkyl or alkenyl groups with 1 to 8 atoms of carbon or cycloalkyl groups with 5 to 8 atoms of carbon, which can be equal or different, and where R3 is a linear-chain or a branched-chain alkyl oder alkenyl group with 1 to 8 atoms of carbon or cycloalkyl group with 5 to 8 atoms of carbon equal to or different from the R2 and R6 residues, or an acyl group with a possibly substituted saturated or olefinic unsaturated aliphatic or cyclo-aliphatic or an aromatic hydrocarbon residue with 1 to 8 atoms of carbon, and where n= 6 or 7. Process for obtaining said cyclodextrins and process for separating chiral organic compounds by chromatographic separation, where the substituted cyclodextrins are used as a stationary phase.

Solvent for paraffin removal from oilfield equipment

Abstract: Paraffin deposits on oilfield equipment, pipelines, tanks and the like are removed on contact with a solvent composition comprising a substantially pure aromatic hydrocarbon and an aliphatic and/or alicyclic hydrocarbon. The solvent composition may contain a surfactant.

Reductive alkylation process

Abstract: A monocycloalkyl aromatic hydrocarbon, e.g. cyclohexyl benzene, or a substituted monocycloalkyl aromatic hydrocarbon is prepared by a hydroalkylation process in which respectively an aromatic hydrocarbon, e.g. benzene, or an alkyl substituted aromatic hydrocarbon is contacted with hydrogen in the presence of a catalyst comprising ruthenium and nickel supported on zeolite beta. Optionally the catalyst can also include a rare earth metal, e.g. lanthanum.

Process for preparing alkyl-substituted aromatic hydrocarbons

Abstract: An alkyl-substituted hydrocarbon is prepared by alkylating an alkyl aromatic hydrocarbon having at least one hydrogen atom at an alpha-position in a side chain with an olefin in the presence of a solid base which is obtainable by heating an alumina, an alkali metal hydroxide and an alkali metal hydride or an alumina containing at least 1.3% by weight of water and an alkali metal hydride in an inert gas atmosphere at a temperature of 200° to 800° C. as a catalyst.

Aerobic bacterial remediation of aliphatic chlorinated hydrocarbon contamination

Abstract: A bacterium of the genus Pseudomonas which utilizes a branched chain alkyl-substituted aromatic hydrocarbon as its sole carbon and energy source and which is capable of substantially complete degradation of trichlorethylene (TCE) at a rate of up to about 32 nmol hr-1 mg cells-1 based upon the dry weight of the cells, and methods utilizing the bacterium for the detoxification of TCE-contaminated material.

Separation of hydrocarbon mixtures

Abstract: An extractive distillation process for separating at least one cycloalkane or aromatic hydrocarbon from at least one close-boiling alkane employs as solvent at least one N-mercaptoalkyl-2-pyrrolidone, preferably N-(β-mercaptoethyl)-2-pyrrolidone, either alone or in admixture with about 0.1-10 weight-% water. A liquid-liquid extraction process for separating at least one cycloalkane or aromatic hydrocarbon from at least one alkane employs as solvent at least one N-mercaptoalkyl-2-pyrrolidone, preferably N-(β-mercaptoethyl)-2-pyrrolidone, either alone or in admixture with about 0.1-10 weight-% water.

Production of hydrocarbon rich in btx

Abstract: PURPOSE: To obtain hydrocarbon rich in BTX in high yield with relatively low reaction pressure by adding light hydrocarbon to hydrocarbon containing (polycyclic) aromatic hydrocarbon and reacting in the presence of zeolite- containing catalyst. CONSTITUTION: (B) 1-50wt.% (preferably 1-30wt.%) in total hydrocarbon of 2-8C light hydrocarbon is added to (A) ≥9C hydrocarbon containing (i) ≥40wt.% aromatic hydrocarbon and (ii) ≥3wt.% polycyclic aromatic hydrocarbon and reacted in the presence of catalyst containing zeolite having ≥1 CI-value, preferably containing at least one metal element selected from Cu, Ag, Zn, Cd, Ga, Cr, W, Se, Te, Re, Co, Ni, Pd, Ir and Pt to afford the aimed hydrocarbon. COPYRIGHT: (C)1991,JPO&Japio

Production of hydrocarbon

Abstract: PURPOSE: To efficiently obtain a hydrocarbon rich in benzene, toluene and xylene by blending a light hydrocarbon with a hydrocarbon containing a polycyclic and a monocyclic hydrocarbons and reacting in the presence of a zeolite- containing catalyst. CONSTITUTION: (A) 2-8C light hydrocarbon is blended with (B) 1-50wt.% (1-30wt.%) based on the total amounts of hydrocarbons of ≥9C hydrocarbon containing 140wt.% aromatic hydrocarbon and ≥3wt.% polycyclic aromatic hydrocarbon. Then the hydrocarbons are reacted in the presence of a catalyst containing a zeolite having ≥1 CI value to give the aimed hydrocarbon. A catalyst containing a metal such as Cu, Ag, Zn, Cd, Ga, Cr, W, Se, Te, Re, Co, Ni, Pd, Ir and Pt may be cited as the catalyst. COPYRIGHT: (C)1991,JPO&Japio

Method for aromatic hydrocarbon recovery

Abstract: A method is provided for the recovery of aromatic hydrocarbons from the extract phase of aromatic-selective solvent extraction process which involves withdrawing a vapor side-cut fraction containing aromatic hydrocarbons and solvent from a stripping zone and passing the side-cut fraction to a rectification zone which can be refluxed with an aqueous condensate. The benefits of the invention are that the introduction of the rectification zone bottoms to the bottom of the stripping section provides an aromatic product comprising less than 100 wt. ppm. solvent, provides improved stripping over prior schemes, and reduces the flowrate of stripping medium throughout the stripping zone which results in energy saving.

Production of particulate polyimide polymers

Abstract: Described is a process for producing, in particu­late form, aromatic polyimides based on one or more 2,2-­bis[4-(aminophenoxy)phenyl]hexafluoropropanes. The process involves forming, heating and agitating in a medium composed of dipolar aprotic solvent and liquid aromatic hydrocarbon solvent, a homogeneous solution of a polyamic acid derived from a substantially equimolar mix­ture of (i) an aromatic tetracarboxylic dianhydride and (ii) a 2,2-bis[4-(aminophenoxy)phenyl]hexafluoropropane, such that a separate phase of particulate aromatic poly­imide is formed in such medium. The process avoids difficulties caused by the tendency of the wet polyimide polymer to agglomerate into stringy or tacky masses which can foul reactor and agitator surfaces.

Catalyst composition for cracking non-aromatic hydrocarbons and isomerizing C8-aromatic hydrocarbons

Abstract: A catalyst composition consisting essentially of (a) a crystalline aluminosilicate zeolite having a silica/alumina mole ratio of at least 10 (component A) in which at least 50% of its cationic sites are occupied by alkaline earth metal cations, (b) a refractory inorganic oxide having platinum and tin supported thereon (component B) and (c) indium (component C), the indium being supported on the zeolite in component A and/or the refractory inorganic oxide in component (B). A process for decomposing non-aromatic hydrocarbons in the presence of the catalyst composition, and a process for isomerizing C 8 -aromatic hydrocarbon, particularly xylenes, in the presence of the catalyst composition.

Process for the preparation of monoalkylated aromatic hydrocarbon

Abstract: A process for preparing monoalkylated aromatic hydrocarbons which comprises: (a) contacting a stoichiometric excess of an aromatic hydrocarbon feed with a C 2 to C 4 olefin in an alkylation zone under at least partial liquid phase conditions and in the presence of a catalyst comprising zeolite beta; (b) separating the product from step (a) into fractions comprising (1) an aromatic hydrocarbon fraction, (2) a monoalkyl aromatic hydrocarbon fraction and (3) a polyalkyl aromatic hydrocarbon fraction; and (c) contacting the polyalkyl aromatic hydrocarbon fraction with additional aromatic hydrocarbon feed in a transalkylation zone under at least partial liquid phase conditions and in the presence of a catalyst comprising zeolite beta.

Alkyl mono and polyglycoside phosphate esters

Abstract: New alkyl mono and polyglycoside phosphate esters and anionic derivatives thereof are described which compounds have the general formula RO(G).sub.x Z.sub.y wherein G is a glycosyl moiety which is selected from the group consisting of fructose, glucose, mannose, galactose, talose, gulose, allose, altrose, idose, arabinose, xylose, lyxose, ribose or mixtures thereof, R is an aliphatic or aromatic hydrocarbon group substituted on the glycosyl moiety which aliphatic or aromatic group is a straight chain or is branched, or is cyclic, saturated or unsaturated and has 6 to 30 carbon atoms; x=1 to 10; y=1 to 3×+1; at least one of the hydroxyl groups at the hydroxyl position of at least one of the glycosyl moieties is substituted with Z which is ##STR1## wherein A=R 1 , H + or (G) x OR B=R 2 , M + or (G) x OR except that when B--R 2 or (G) x OR, A≠H, when A or B=(G) x OR, Z substitutes one of the hydroxyl groups of the glycosyl moieties of A or B, and R 1 and R 2 =an aliphatic or aromatic hydrocarbon group which is a linear straight chain or is branched, open-chain or cyclic, saturated or unsaturated and has 6 to 30 carbon atoms or CH 3 (CH 2 ) m (CH 2 ) n , m and n=1 to 27 with m+n greater than or equal to 5 with the total number of carbon atoms in R 1 +R 2 not exceeding 50; M=an organic or inorganic cation.

Preparation of olefin polymerization catalyst and polymerization of olefin

Abstract: PURPOSE: To prepare the subject polymerization catalyst giving highly stereoregular polymers in high yields by forming a solid catalyst component comprising a Mg compound, a Ti compound and a halogen-containing compound as essential components and subsequently treating the catalytic component with a specific alkoxy ester compound CONSTITUTION: A solid catalyst component comprising a magnesium compound (eg magnesium chloride), a titanium compound (eg titanium tetrachloride) and a halogen-containing compound (eg 1,2-dichloroethane) as essential components is formed and simultaneously or subsequently treated with one kind or more of alkoxy ester compounds (eg 3-ethoxy-2-phenylpropionic acid ethyl ester) of the formula [R 1 -R 4 are aliphatic hydrocarbon, alicyclic hydrocarbon, aromatic hydrocarbon, heterocyclic hydrocarbon, etc; Z is H, (substituted) aliphatic or alicyclic hydrocarbon; i, j, k are 0-3; the sum of i, j and k is 1 or more] to provide the objective polymerization catalyst component COPYRIGHT: (C)1990,JPO&Japio

Aromatic hydrocarbon-based emulsion explosive composition

Abstract: An emulsion explosive composition comprising a discontinuous oxidizer phase and a continuous fuel phase is provided wherein the fuel phase comprises an aromatic hydrocarbon compound. The composition essentially contains as the emulsifying agent a polyisobutylene succinic anhydride-based compound in admixture with an ester of 1-4 sorbitan and oleic acid. The composition demonstrates high explosive strength and excellent stability.

Novel alkylaromatic lubricant fluids

Abstract: Aromatic compounds are alkylated with C₂₀-C₁₃₀₀ olefinic oligomers by contacting the oligomers and aromatic compounds with an acidic catalyst to produce novel alkylated aromatic hydrocarbon compositions useful as lubricant basestock and additives. The olefinic oligomers used as alkylating agents are prepared from 1-alkene oligomerization in contact with a reduced chromium oxide catalyst on silica support. In one embodiment, the aromatic compounds are alkylated with a mono-olefinic HVI-PAO dimer which is prepared as a product or by-product from 1-alkene oligomerization using reduced chromium oxide on solid support. The alkylated aromatic hydrocarbons retain the unique features of the alkylating olefinic oligomer and exhibit high viscosity index and low pour point. The novel alkylaromatic compositions show improved thermal stability; also, the compositions are useful as lubricant additives for improved antiwear properties, antioxidant and other properties.

Separation of toluene diisocyanate from the residues of the production thereof

Abstract: Toluene diisocyanate (TDI) is separated and recovered from the residues of the production thereof, e.g., from the tars of phosgenation of an aromatic diamine, by extracting such residues with an extractant which comprises an inert gas, e.g., CO2, in either the liquid or supercritical state, optionally in the presence of a coextractant diluent, for example an ester, aromatic hydrocarbon or chlorinated aromatic hydrocarbon, or chlorinated aliphatic hydrocarbon.

Fluorine-containing alicyclic and aromatic cyclic compounds and production thereof

Abstract: NEW MATERIAL:A fluorine-containing alicyclic or aromatic cyclic compound expressed by formula I (M is bifunctional organic group consisting o at least one cyclic aliphatic hydrocarbon group which may have a substituent group or at least two aromatic hydrocarbon groups which may have a substituent group; M may be linked with O, S, CH2, etc., or may form a condensed ring when the above-mentioned bifunctional organic group consists of two or more of the aforementioned cyclic aliphatic hydrocarbon groups which may have the substituent group or the above-mentioned aromatic hydrocarbon groups which may have the substituent group; X is formula II or III: Y is H or CH3; n is 0 or a positive number). USE:Useful as a raw material for adhesives, etc., having excellent water and heat resistance, refractive index and strength and curable by irradiation with active energy rays in the presence of an initiator, etc., to provide cured products useful as an optical material. PREPARATION:A compound expressed by formula IV is reacted with epichlorohydrin and a dehydrochlorinating agent to afford the aimed compound expressed by formula I.

Detergent for waterproof cable

Abstract: PURPOSE:To obtain the title detergent excellent in detergency for jelly, safety and sanitariness by mixing a specified n-paraffin with an aromatic hydrocarbon, an oil-soluble dye and a perfume each in a specified amount. CONSTITUTION:A detergent prepared by mixing a specified 11-17C n-paraffin, e.g. a mixture of n-undecane, n-dodecane and n-tridecane, with 1-20wt.% aromatic hydrocarbon, e.g. xylene, 0.0001-1.0wt.% oil-soluble dye, e.g. C.I. Solvent Red 24, and 0.001-10ppm perfume, e.g. benzyl acetate.

Production of rigid polyurethane foam

Abstract: PURPOSE: To produce a rigid polyurethane foam reduced in thermal conductivity by using a polyol component comprising a specified aromatic polyester polyol and a specified aromatic polyamine-based polyether polyol and a blowing agent such as a low-boiling hydrocarbon. CONSTITUTION: 20-50wt.% aromatic polyester polyol of a hydroxyl value of 200-400, obtained by reacting an aromatic carboxylic acid (anhydride) with a bi- or tri-hydric alcohol having a 3-12C aromatic hydrocarbon chain and effecting the addition reaction of the product with an alkylene oxide, is mixed with 80-30wt.% aromatic polyamine-based polyether polyol of a hydroxyl value of 300-600, obtained by effecting the addition reaction of an aromatic polyamine with an alkylene oxide, to form a polyol component. This component is mixed with a blowing agent such as a mixture of a low-boiling hydrocarbon with water, a foam stabilizer, and an amine catalyst to form a polyol premix. This premix is mixed with a polyisocyanate component in an NCO to OH equivalent ratio of about 1.00-1.35, and the resultant mixture is poured into a mold and expanded to obtain a rigid polyurethane foam having a low thermal conductivity.

Method for purifying 3,3',5,5'-tetraalkyl-4,4'-biphenol

Abstract: PURPOSE:To readily obtain the title high-purity compound especially useful as a raw material for resins, by heat-treating the title compound prepared by oxidative coupling of a 2,6-dialkylphenol in an >=8C aromatic hydrocarbon solvent at a specific temperature or above. CONSTITUTION:A 2,6-dialkylphenol is subjected to oxidative coupling to provide the title compound containing impurities, such as diphenoquinones or polyphenylene ethers. The resultant title compound is then preferably heat- treated in an >=8C aromatic hydrocarbon solvent, such as xylene, ethylbezenc, diethylbenzene, cumene or tert-butylbezene, in an amount of preferably 3-10 pts.wt. based on 1 pt.wt. afore-mentioned compound at >=120 deg.C, preferably 130-170 deg.C temperature and subsequently cooled to <=80 deg.C, preferably ordinary temperature -40 deg.C temperature to readily, industrially and advantageously afford the title white and high-purity compound useful as various chemical intermediates, etc., with simply practicable recovery of the solvent, etc.

Method for separating solvent

Abstract: PURPOSE: To separate an aromatic hydrocarbon phase and an aqueous phase by regulating the ratio of methanol to water in a solvent, recovered in a production process for polyphenylene ether and containing benzene, toluene, xylene, etc., the methanol and water within a specific range. CONSTITUTION: Phase separation of an aromatic hydrocarbon from a solvent, recovered in a production process for polyphenylene ether and containing benzene, toluene and/or xylene, methanol and water is carried out. In the process, the ratio of the methanol to water in the aforementioned solvent is regulated so as to provide 55-78wt.% (preferably 58-75wt.%) and the separation is then performed using a column type separator, centrifugal separator, etc. Since efficiency of the phase separation is excellent according to the aforementioned method, use of a large-scale apparatus is not required. Thereby, the method is carried at a low cost. Since solid substances are not deposited in the separated phase, there is no fear of clogging the columns, etc. COPYRIGHT: (C)1991,JPO&Japio