Abstract: The present invention relates to a method and apparatus for continuous recovery of (meth)acrylic acid, and more specifically to a method of continuous recovery of (meth)acrylic acid, including: conducting gas phase oxidation of at least one compound selected from the group consisting of propane, propylene, butane, i-butylene, t-butylene, and (meth)acrolein in the presence of a catalyst to obtain a mixed gas containing (meth)acrylic acid; quenching the (meth)acrylic acid-containing mixed gas to remove high boiling point by-products in the (meth)acrylic acid-containing mixed gas; contacting the high boiling point by-product-free (meth)acrylic acid-containing mixed gas with water or an aqueous solution to obtain an aqueous solution containing (meth)acrylic acid; and purifying the aqueous solution containing (meth)acrylic acid to obtain (meth)acrylic acid.

Abstract: A method for producing a catalyst for the preparation of methacrylic acid comprising a heteropolyacid compound containing phosphorus, molybdenum and an element X selected from the group consisting of potassium, rubidium, cesium and thallium and having an atomic ratio of the element X to molybdenum of 0.5:12 to 2:12, which method comprises the steps of mixing aqueous slurry A containing starting compounds of the heteropolyacid compound in which an atomic ratio of the element X to molybdenum is from 2:12 to 4:12, and aqueous slurry B containing starting compounds of the heteropolyacid compound in which an atomic ratio of the element X to molybdenum is from 0:12 to 0.5:12 to form a slurry mixture; heat-treating the slurry mixture at a temperature of 100° C. or higher; drying the slurry mixture; and calcining the dried mixture.

Abstract: Disclosed is a method for producing a catalyst, in which physical properties of a dried material or a calcined material in a production process of the catalyst are stable and a change in at least one of a catalyst activity and a selectivity to a target product is small and hence reproducibility of the catalyst is excellent. The present invention is a method for producing a catalyst containing molybdenum, bismuth, and iron, which contains the steps of washing a surface of at least one device equipped in an apparatus for the production of catalyst, to which a solid matter adheres, with a basic solution, and producing the catalyst with the apparatus for the production of catalyst thus washed.

Abstract: A system and process for separating methacrolein (MA) from methacrylic acid (MAA) and acetic acid in the gas phase product from partial oxidation of isobutylene (IB) in two oxidation steps is disclosed. The process and system maximize recovery of all three components at minimum capital and energy cost, under conditions that minimize polymerization conditions and plugging by solids deposition in compressors, columns, etc.

Abstract: Disclosed is a shell-and-tube reactor or heat exchanger, which alternately comprises a doughnut-type baffle plate and a first disc-type baffle plate in order to increase heat transfer efficiency. In the reactor or heat exchanger, a second disc-type baffle plate is placed in an empty space inside of the doughnut-type baffle plate, and some tubes, through the inside of which a first object for heat transfer with a heat transfer medium, are present in a region inside of the doughnut-type baffle plate and outside of the second disc-type baffle plate. Also disclosed is a method for producing an oxide, comprising: using said reactor or heat exchanger, and causing a catalytic vapor-phase oxidation reaction in the tubes, through the inside of which the first object for heat transfer with the heat transfer medium is passed.

Abstract: The objective of the present invention is to provide a method for inhibiting polymerization of (meth)acrylic acid and the like. By the method, the generation of deposit in a pipe, which is exclusively used for providing a solution of a dialkyldithiocarbamic acid copper salt to a distillation column and the like, is prevented, and the problems such as the clogging of the pipe and polymerization in the distillation column are solved. The method according to the present invention for inhibiting polymerization of (meth)acrylic acid and/or an ester thereof is characterized in comprising a step of inhibiting polymerization of (meth)acrylic acid and/or the ester thereof by using a solution of a dialkyldithiocarbamic acid copper salt dissolved in an organic solvent, wherein a content amount of copper sulfate in the solution of the dialkyldithiocarbamic acid copper salt is 100 ppm or less by mass.

Abstract: A process for the oxidation of hydrocarbons comprises contacting the hydrocarbon with an oxygen-containing gas in the presence of a catalyst comprising a microporous solid support, preferably a zeolite, having from 8- to 12-ring open windows and comprising non-framework metal cations selected from manganese, iron, cobalt, vanadium, chromium, copper, nickel, and ruthenium, and mixtures thereof, providing that the oxygen-containing gas does not contain significant amounts of added hydrogen. The catalyst is novel and forms part of the invention. The process may be used for oxidation of alkanes, cycloalkanes, benzene and alkylbenzenes, and is suitable for use in regioselective terminal oxidation of straight chain alkanes and for selective oxidation/separation of p-dialkylbenzenes from an alkylbenzene mixture, for example, p-xylene from an isomeric mixture of xylenes.

Abstract: A process produces a corresponding dicarboxylic acid by subjecting a cycloalkane to an oxidative cleavage reaction with oxygen in the presence of a catalyst in a liquid phase using a continuous reactor, in which a residence time ? (hr) satisfies the following condition: 0.1???50/c, wherein c is the proportion (% by weight) of the cycloalkane to the total weight of a charged liquid. The catalyst includes, for example, cobalt compounds, manganese compounds, and mixtures of these compounds, as well as imide compounds having at least one cyclic imide skeleton.

Abstract: A process for preparing at least one target product by partial oxidation and/or ammoxidation of propylene, in which the propylene source used is a propane dehydrogenation, the propane used therein being obtained by a rectificative prepurification of crude propane.

Abstract: The present invention relates to the oxidation with oxygen, or a gas containing it, of hydrocarbons to the corresponding carboxylic acids, alcohols and/or ketones or of alcohols and/or ketones to the corresponding carboxylic acids. More specifically, the invention consists of a process for oxidizing hydrocarbon, alcohol and/or ketone using oxygen or a gas containing it, in a liquid phase and in the presence of a catalyst dissolved in the reaction medium, characterized in that the catalyst comprises at least one soluble manganese and/or cobalt compound, at least one soluble chromium compound and at least one soluble iron compound.

Abstract: An object of the present invention is to provide a highly active catalyst for producing an unsaturated oxygen-containing compound from an alkane and the catalyst comprising Mo, V, Ti and Sb or Te as the indispensable active components. The preferable catalyst is represented by formula (1) or (2) as shown below, Mo1.0VaTibXcYdOe??(1) Mo1.0VaTibXcYdZfOe??(2) wherein X represents Sb or Te; Y represents Nb, W or Zr; Z represents Li, Na, K, Rb, Cs, Mg, Ca or Sr; a, b, c, d, e and f represent atomic ratios of their respective elements, with 0<a<0.7, 0<b<0.3, 0<c<0.7, 0?d<0.3, 0<f<0.1; e is a number determined by oxidation states of the other elements than oxygen.

Abstract: A process for the production of carboxylic acids by oxidation of a hydrocarbon by oxygen or a gas containing oxygen and notably to the oxidation of cyclohexane to give adipic acid; the subject process entails a stage of oxidation of the hydrocarbon and at least one stage for extracting the dicarboxylic acids formed from the reaction medium and optionally recycling the unconverted hydrocarbon with oxidation by-products, such as alcohols and ketones, and which also includes a stage of conversion, removal or extraction of the ?,?-hydroxycarboxylic compounds formed during the oxidation stage and converting these compounds into diacids.

Abstract: Disclosed is a process for producing unsaturated aldehydes and/or unsaturated acids from olefins or alkanes in a fixed bed shell-and-tube heat exchanger-type reactor by catalytic vapor phase oxidation. A heat exchanger-type reactor for use in such a process is also disclosed. The process utilizes at least one first-step reaction zone and a second-step reaction zone that is divided into two or more shell spaces by at least one partition. The process may be applied to a single-step process for producing unsaturated acids from alkanes or alkenes.

Abstract: A process for preparing acrolein, or acrylic acid or a mixture thereof as a target product from propane, in which propane is partially dehydrogenated under heterogeneous catalysis in a reaction zone A, molecular hydrogen thus formed is incinerated partly to water and the product gas A thus formed in reaction zone A is used without secondary component removal to charge a reaction zone B in which propylene present in product gas A is partially oxidized to the target product. From the product gas B formed in reaction zone B, the target product is removed and the residual gas I remaining after an aftertreatment comprising a CO2 scrubbing and a partial discharge thereof is recycled into reaction zone A.

Abstract: The invention relates to a method for preparing acrylic acid from propylene, comprising the oxidation of propylene to acrolein and a second step comprising the oxidation of acrolein to acrylic acid, including a glycerol dehydration step preformed in the presence of a gas containing propylene and, more specifically, in the presence of the reaction gas originating from the propylene to acrolein oxidation step. The inventive method enables the use, in part, of renewable raw material, while increasing acrylic acid production.

Abstract: A method for quickly starting up a reactor and a reactor system therefor are provided. A shell-and-tube reactor in the system is adapted to circulate a heat medium having a solid point in the range of 50-250° C. to the outside of the reaction tubes and characterized by initiating temperature elevation of the reactor by introducing a gas of a temperature in the range of 100-400° C. to the reaction tubes' side and then circulating the heat medium in a heated state to the outside of the reaction tubes. By introducing a gas of an elevated temperature preparatorily to the reaction tubes, it is made possible to prevent the heat medium after circulation from being solidified again and enable the reactor to be quickly started up.

Abstract: A process for the preparation of a dicarboxylic acid, comprising the steps of (a) contacting a conjugated diene with carbon monoxide and water in the presence of a catalyst system including a source of palladium, a source of an anion and a bidentate phosphine ligand, to obtain a mixture comprising an ethylenically unsaturated acid product; (b) reacting the mixture obtained in step (a) further with carbon monoxide and water to obtain the dicarboxylic acid in admixture with the ethylenically unsaturated acid; (c) separating the dicarboxylic acid from a liquid filtrate comprising the catalyst system; and (d) recycling at least part of the obtained liquid filtrate to step (a).

Abstract: An improved process for the production of unsaturated carboxylic acids and unsaturated nitriles from their corresponding C3 to C5 alkanes, or mixtures of C3 to C5 alkanes and alkenes, that involves oxidation in the presence of a supported Mo-V-based mixed metal oxide catalyst in a multi-stage reaction system which employs both separation of the oxidation product from one or more intermediate effluent streams, as well as feeding additional oxygen to reaction zones subsequent to the first reaction zone.

Abstract: Provided herein are processes for conversion of methane to acetic acid. In one embodiment, the processes are for direct, selective conversion of methane to acetic acid in a single step.

Abstract: Alkenes, unsaturated saturated carboxylic acids, saturated carboxylic acids and their higher analogues are prepared cumulatively from corresponding alkanes utilizing using a multi-staged catalyst system and a multi-stage process which comprises steam cracking of alkanes to corresponding alkenes at flame temperatures and at short contact times in combination with one or more oxidation catalysts for catalytically converting the corresponding alkenes to further corresponding oxygenated products using short contact time reactor conditions.

Abstract: A shell-and-tube type heat exchanger of the smallest possible length necessary for heat exchange is disclosed which is capable of obtaining uniform distribution of flow of a shell side fluid and substantially eliminating the structural restriction imposed on the shell side. This shell-and-tube type heat exchanger is provided with one annular conduit furnished with not less than two partitions concurrently serving as an expansion joint for introducing and discharging a shell side fluid and allowing the flow path for said shell side fluid to be separated into an introducing part and a discharging part and which comprises a place having no array of heat-transfer tubes in the flow path for said shell side fluid. It prevents the equipment from necessitating an unnecessary enlargement due to the structural restriction on the shell side and enables the shell side fluid to produce a uniform flow.

Abstract: This invention relates to a process for converting a hydrocarbon reactant to a product comprising an oxygenate or a nitrile, the process comprising: (A) flowing a reactant composition comprising the hydrocarbon reactant, and oxygen or a source of oxygen, and optionally ammonia, through a microchannel reactor in contact with a catalyst to convert the hydrocarbon reactant to the product, the hydrocarbon reactant undergoing an exothermic reaction in the microchannel reactor; (B) transferring heat from the microchannel reactor to a heat exchanger during step (A); and (C) quenching the product from step (A).

Abstract: A process for preparing (meth)acrylic acid by heterogeneously catalyzed gas phase partial oxidation of a saturated hydrocarbon precursor compound, in which the charging gas mixture contains from 5 to 25% by volume of steam and the molar ratio of molecular oxygen present in the charging gas mixture to saturated hydrocarbon precursor compound present in the charging gas mixture is from 1.5:1 to 2.5:1.

Abstract: A method for producing acrylic acid by using an acrylic acid-containing solution of high concentration without azeotropic distillation is provided. This method of producing acrylic acid comprises introducing an acrylic acid-containing gas obtained by catalytic gas phase oxidation reaction into an absorption column and supplying the acrylic acid-containing solution to crystallization step thereby separating the solution into acrylic acid and residual mother liquid, and distilling at least part of the residual mother liquid and circulating the distillate obtained by the distillation to the absorption column.

Abstract: A multimetal oxide material contains the elements Mo, V and Te and/or Sb and at least one of the elements Nb, Ti, W, Ta and Ce and promoters and has a specific X-ray diffraction pattern. Moreover, such a multimetal oxide material is used as a catalyst for heterogeneously catalyzed gas-phase partial oxidations of hydrocarbons.

Abstract: A process for the oxidation of a C2 to C4 alkane to produce the corresponding alkene and carboxylic acid which process comprises contacting in an oxidation reaction zone, said alkane, molecular oxygen-containing gas, and the corresponding alkene and optionally, water, in the presence of at least one catalyst active for the oxidation of the alkane to the corresponding alkene and carboxylic acid, to produce a product stream comprising alkene, carboxylic acid and water, wherein in said process the molar ratio of alkene to carboxylic acid produced in said oxidation reaction zone is adjusted or maintained at a pre-determined value by controlling the concentrations of the alkene and optional water in said oxidation reaction zone and optionally by also controlling one or more of the pressure, temperature and residence time of the oxidation reaction zone. Such an oxidation process may be used in an integrated process, such as for the manufacture of vinyl acetate or ethyl acetate.

Abstract: A continuously operated heterogeneously catalyzed gas-phase partial oxidation of at least one organic compound in an oxidation reactor is operated safely by a process in which an explosion diagram for the feed gas mixture is deposited as the basis of a cut-out mechanism in a computer.

Abstract: The present invention relates to a process for oxidizing hydrocarbons, in particular branched or unbranched saturated aliphatic hydrocarbons, cycloaliphatic or alkylaromatic hydrocarbons to acidic or polyacidic compounds. The invention relates more particularly to the oxidation, with an oxidizing agent containing molecular oxygen, of cyclohexane to adipic acid, in the presence of organic acid of lipophilic nature and in the absence of adipic acid. The separation and recycling of the unoxidized cyclohexane, the oxidation intermediates and the catalysts are easier than in the presence of acetic acid.

Abstract: A process for preparing a multimetal oxide material which contains the elements Mo, V and Te and/or Sb and at least one of the elements Nb, Ti, W, Ta and Ce and if desired promoters and has a specific X-ray diffraction pattern, in which process the last process step comprises washing with acidic liquids. In addition, a multimetal oxide material obtainable in such a way is used as a catalyst for heterogeneously catalyzed gas-phase partial oxidations and/or ammoxidation of hydrocarbons.

Abstract: A carboxylic acid is produced by oxidative cleavage of a cycloalkane with oxygen and performs a reaction in the presence of a catalyst including an imide compound and a metallic compound, the imide compound having a cyclic imide skeleton represented by the following Formula (I): wherein X is an oxygen atom or an —OR group, and wherein R is a hydrogen atom or a hydroxyl-protecting group, under conditions of a reaction temperature of 80° C. or higher and a concentration of the cycloalkane of 21% by weight or more.

Abstract: The present invention provides a process in which, when an unsaturated aldehyde and/or an unsaturated carboxylic acid are produced by carrying out a catalytic gas phase oxidation reaction by using a fixed-bed multitubular reactor which is packed with a molybdenum-containing catalyst, the deterioration of the catalyst as located at a hot spot portion can be suppressed; so that the reaction can be continued for a long time while a high yield is maintained, regardless of where the hot spot portion occurs and also even if the concentration of a raw gas is high.

Abstract: Organic compounds are prepared by heterogeneously catalyzed partial gas-phase oxidation of precursor compounds by a process in which a portion of the reaction gas starting mixture is brought from a low initial pressure to a higher final pressure by means of a radial compressor.

Abstract: In a process for preparing acrylic acid, an acrylic acid-containing product gas mixture obtained by catalytic gas phase partial oxidation of a C3 precursor of acrylic acid, after direct cooling with a quench liquid, is fractionally condensed in a separating column provided with internals, rising into itself with sidestream takeoff of crude acrylic acid, and the acrylic acid oligomers which form are dissociated and the resulting dissociation gas is subjected to a countercurrent rectification before it is recycled.

Abstract: A process prepares methacrylic acid from isobutane by subjecting isobutane to a partial catalytic dehydrogenation in the gas phase and charging an oxidation zone with the isobutenic product gas mixture after the components other than isobutane and isobutene have been substantially removed from the product gas mixture. The oxygen required to charge the oxidation zone is introduced accompanied by nitrogen.

Abstract: In producing a catalyst used for synthesis of an unsaturated aldehyde and an unsaturated carboxylic acid by a gas-phase catalytic oxidation, there is used a step of packing an additive-containing catalyst precursor of the catalyst into a tubular reactor, passing a gas through the tubular reactor, and elevating, in this state, the temperature of the additive-containing catalyst precursor so that a temperature of the gas at an outlet of the catalyst precursor layer becomes higher than a temperature of the gas at an inlet of the catalyst precursor layer. The step makes possible easy and highly reproducible production of a high-performance catalyst which is small in the reduction in catalytic performance caused by, for example, the thermal decomposition of the additive contained in the catalyst precursor.

Abstract: An object of this invention is to provide a method for producing acrylic acid that enables to suppress adverse influence of byproducts during distillation and to accomplish long-term continuous operation of the acrylic acid production apparatus. This invention is directed to a method for producing (meth)acrylic acid comprising the step of isolating (meth)acrylic acid from a liquid containing (meth)acrylic acid by distillation wherein the liquid contains glyoxal (including its hydrate) in a concentration of 0.1 mass % or less.

Abstract: The invention relates to a method for producing acrylic acid by the heterogeneously catalysed gas-phase oxidation of propane on a multi-metal oxide mass, said mass containing the elements Mo, V, Te and/or Sb and having a specific X-ray diffractogram.

Abstract: Acrylic acid is prepared by heterogeneously catalyzed partial oxidation of propane by a process in which the steam content of the reaction gas starting mixture is reduced in the course of the process.

Abstract: The invention relates to a process for manufacturing acrylic acid from propane. According to this process, a gas mixture, which is free from molecular oxygen and comprises propane, steam as well as, optionally, an inert gas, is passed over a solid composition of formula (I) Mo1VaTebNbcSidOx  (I) in which: a is between 0.006 and 1, including the end points; b is between 0.006 and 1, including the end points; c is between 0.006 and 1, including the end points; d is between 0 and 3.5, including the end points; and x is the quantity of oxygen bound to the other elements, and depends on their oxidation states, in order to oxidize the propane according to the following redox reaction (1): SOLIDoxidized+PROPANE→SOLIDreduced+ACRYLIC ACID  (1).

Abstract: The invention relates to a method for catalytically oxidizing unsaturated hydrocarbons to form oxidation products, and to the production of saturated alcohols, ketones, aldehydes or carboxylic acids by subsequently hydrogenating the oxidation product. A compound of formula (I) is used as a catalyst during oxidizing in which: R1, R2═H, an aliphatic or aromatic alkoxy radical, carboxyl radical, alkoxycarbonyl radical or hydrocarbon radical, each having 1 to 20 carbon atoms, SO3H, NH2, OH, F, Cl, Br, I and/or NO2, whereby R1 and R2 signify identical or different radicals or R1 and R2 can be coupled to one another via a covalent bond, with Q1, Q2=the same or different, C, CH, N; X, Z═C, S or CH2; Y═O or OH; k=0, 1 or 2; 1=0, 1 or 2; m=1 to 100 in the presence of a radical initiator. Peroxy compounds or azo compounds can be used as radical initiators. Preferred substrates are cyclic aliphatic or aromatic compounds.

Abstract: The present invention relates to a process for the oxidation of hydrocarbons, in particular of branched or unbranched saturated aliphatic hydrocarbons, of cycloaliphatic or alkylaromatic hydrocarbons or of alcohols and/or ketones, to acid or polyacid compounds.

Abstract: A catalyst comprising a promoted mixed metal oxide is useful for the vapor phase oxidation of an alkane or a mixture of an alkane and an alkene to an unsaturated carboxylic acid and for the vapor phase ammoxidation of an alkane or a mixture of an alkane and an alkene to an unsaturated nitrile.

Abstract: A catalyst comprising an In promoted mixed metal oxide is useful for the vapor phase oxidation of an alkane, or a mixture of an alkane and an alkene, to an unsaturated carboxylic acid and for the vapor phase ammoxidation of an alkane, or a mixture of an alkane and an alkene, to an unsaturated nitrile

Abstract: A catalyst comprising a promoted mixed metal oxide is useful for the vapor phase oxidation of an alkane or a mixture of an alkane and an alkene to an unsaturated carboxylic acid and for the vapor phase ammoxidation of an alkane or a mixture of an alkane and an alkene to an unsaturated nitrile.

Abstract: A modified carrier carrying on at least a part of an inert carrier surface an oxide which is represented by the formula (1): XaYbZcOd (wherein X is at least an element selected from alkaline earth metals; Y is at least an element selected from Si, Al, Ti and Zr; Z is at least an element selected from Group IA elements and Group IIIb elements of the periodic table, B, Fe, Bi, Co, Ni and Mn; and O is oxygen; a, b, c and d denote the atomic ratios of X, Y, Z and O, respectively, where a=1, 0<b≦100, 0≦c≦10, and d is a numerical value determined by the extents of oxidation of the other elements) is provided. A catalyst formed with the use of this modified carrier carrying a complex oxide containing Mo and V is useful as a vapor-phase catalytic oxidation catalyst, and is particularly suitable as a catalyst for preparing acrylic acid through vapor phase catalytic oxidation of acrolein.

Abstract: A catalyst comprising a promoted mixed metal oxide is useful for the vapor phase oxidation of an alkane or a mixture of an alkane and an alkene to an unsaturated carboxylic acid and for the vapor phase ammoxidation of an alkane or a mixture of an alkane and an alkene to an unsaturated nitrile.

Abstract: Reactor membranes for used in oxidation reactions of hydrocarbons involving oxygen comprising a selective oxidation catalyst on a mixed conducting, oxide ion selective ceramic membrane of the composition (Sr1-xCax)1-yAyMn1-zBzO3-&dgr;, where A is Ba, Pb, Na, K, Y, an element of the lanthanide group or a combination thereof, B is Mg, Al, Ga, In, Sn, an element of the 3d or 4d period or a combination thereof, x is from 0.2 to 0.8, y is from 0 to 0.4, z is from 0 to 0.6, and &dgr; is a number, dependent on x, y and z, that renders the composition charge neutral.

Abstract: A process for the production of acetic acid, which process comprises contacting ethane and/or ethylene with a molecular oxygen-containing gas in a fluid bed reactor in the presence of a microspheroidal fluidised particulate solid oxidation catalyst, wherein at least 90% of said catalyst particles are less than 300 microns.

Abstract: A process for the heterogeneously catalyzed gas-phase partial oxidation of an organic compound over a fixed catalyst bed present in a fixed-bed reactor having a plurality of catalyst tubes, in which the reduction of the quality of the catalyst load with increasing duration of operation is restored by a partial catalyst change, is described.

Abstract: A continuously operated heterogeneously catalyzed gas-phase partial oxidation of at least one organic compound in an oxidation reactor is operated safely by a process in which an explosion diagram for the feed gas mixture is deposited as the basis of a cut-out mechanism in a computer.