153 results about "Durene" patented technology

The invention discloses a craft for producing pyromellitic dianhydride catalyzed by a carrier-type poly-oxometalate, including melting the pyromellitic dianhydride by the groove, feeding to the mixing machine for evapouration after pre-heating with a feed concentration of 15.0-19.5g/m3, mixing with the air, entering into the fixed bed reactor for a oxidation, oxidating with an airspeed of 4500-6500 h-1, cooling the produced air, then condensing in the collector, getting coarse pyromellitic dianhydride. At 300-340 DEG C, the catalyzer is mostly poly-oxometalate which is fixed on the catalyst bed after loading. The mass ratio of the catalyzer to pyromellitic dianhydride is 0.2-1%. The invention has the durene in the C10 heavy aromatics as raw material, produces the pyromellitic dianhydride by oxidation in air, makes the C10 heavy aromatics be with a higher added value, uses the current resource and industrial equipments as more as possible, exploits the catalysis and synthesis path of the pyromellitic dianhydride. The invention has a low pollution and production cost, a wide development prospect and is suitable for commercial process.

Synthetic fuels are produced from synthesis gas in a four-stage reactor system with a single recycle loop providing the requisite thermal capacity to moderate the high heat release of the reactions and to provide the reactants and reaction environments for the efficient operation of the process. The first stage converts a portion of the synthesis gas to methanol, the second stage converts the methanol to dimethylether, the third stage converts the methanol and dimethylether to fuel and the fourth stage converts the high melting point component, durene, and other low volatility aromatic components such as tri- andtetra-methylbenzenes to high octane branched paraffins. The four-stage catalyst used for hydrotreating is resistant to CO poisoning. The reactions i produce water as a side product that is carried through to a high pressure separator after the fourth stage. The streams from the separator are a liquid fuel stream, a water stream and a gaseous stream that contains light hydrocarbon gases and the unreacted synthesis gas. The larger part of this gas stream is recycled to the inlet of the first stage and mixed with the fresh synthesis gas stream. Alternatively, the fresh synthetic gas stream is mixed with the product of the second stage. The smaller part of the gas stream from the separator is sent to hydrocarbon recovery and to fuel gas used for providing preheat of various streams. The liquid fuel is sent for blending into fuel products, such as gasoline, jet fuel, or diesel, and the water stream can be sent, for example, to the synthesis gas producing plant for steam generation.

The present invention discloses a method for jointly preparing a series of products of an aromatic solvent, petronaphthalene and durene from a C10 heavy aromatics material, belonging to the C10 heavy aromatics complex utilization technical field. The method comprises the following steps of: A) separating the C10 heavy aromatics material; B)refrigerating and crystallizing an enrichment solution of durene; C)refrigerating and crystallizing an enrichment solution of naphthalene; D) gas phase catalytically oxidizing durene; and E) preparing technical grade PMA, technical grade PMDA and electronic grade PMDA from a crude product. The method has the advantages that the method can carry out joint production to obtain the series of products of aromatic solvent, petronaphthalene and durene by the C10 heavy aromatics material so that the C10 heavy aromatics material obtains sufficient utilization, thereby contributing to resource economizing.

The molecular sieve catalyst for synthesizing methanol into durene is ZSM-5 type with molar Si/Al ratio of 13-50, strong/weak acid ratio of 1.03-1.30, adsorption amount to cyclohexane of 5.95-6.25 wt%, said adsorption amount to n-hexane of 8.95-9.15 wt%. The hydrogen-type molecular sieve, assistant and nitric acid are mixed and kneaded, and the mixture is formed, stoved, crushed, roasted, soakingin acid solution, stoved and roasted to obtain the catalyst. The present invention has the advantages of simple preparation process, high selectivity of the catalyst, and the durene content in the product as high as 20%.

The invention provides a catalyst and a preparation method and application thereof, and a preparation method for durene. The catalyst is mainly prepared from the following components by weight: 45 to 85% of a beta-molecular sieve, 10 to 55% of a binder and 0 to 10% of a modified element, wherein the binder is one or more selected from a group consisting of alumina, alumina sol and silica sol, and the modified element is one or more selected from a group consisting of zinc, iron, magnesium, calcium and rare earth elements. The catalyst has high catalytic activity to alkylation and can substantially improve the conversion rate of pseudocumene in preparation of durene from pseudocumene and methanol.

The invention relates to a technique for reforming a C10 arene to produce a durene, the reforming to the C10 arene undergoes steps of continuous rectification, freezing crystallization and separation by three rectification towers for separating out the durene front low-boiling fraction, rectifying out the durene liquid rich mother liquor and then extracting out the product before 205 DEG C by rectification; and the durene rich mother liquor is cooled to the temperature of between -5 and -10 DEG C through a refrigerating kettle, the durene in the rich liquid is saturated and separated out of a crystalline solid, and a solid durene product is obtained through fractional crystallization and pressure filtration. The product of the invention has the yield reaching 80 percent and the purity reaching 99 percent; and the technique is environment-friendly and energy-saving and will not produce smoke gas by applying the coal gas produced by itself. The technique has advantages of reducing the amount of freezing materials, increasing the freezing temperature and obviously saving the power, and has broad application prospect.

The invention relates to a method and a device for extracting durene from methanol synthetic oil. The device comprises a fractionating tower, a dividing wall tower crystallization system and a plurality of pumps, wherein condensers and return tanks are arranged at the tops of the fractionating tower and the dividing wall tower; reboilers are arranged at the bottoms of the towers; a partition plate is arranged inside the dividing wall tower; the dividing wall tower is partitioned into a distillation zone I, a feeding zone II, an intermediate product zone III and an extraction zone IV; a raw material enters the fractionating tower, and is connected to a dividing wall tower feeding zone II from a discharge pipeline at the bottom of the fractionating tower; the intermediate product zone III of the dividing wall tower is arranged in an opening of a dividing wall tower discharge pipe; and the opening of the dividing wall tower discharge pipe is connected to the inlet of the crystallization system by adopting a production line. The functions of lightly cutting, heavily cutting and gathering and refining the durene are integrated into the dividing wall tower to achieve after naphtha and the like in the synthetic oil are removed, and the equipment such as a rectifying tower, attached condensers and reboilers thereof and the like can be removed. Thus, energy consumption and equipment investment in the process are reduced, and the energy consumption in the process can be reduced by over 10% by adopting the dividing wall tower technology.

The invention provides an oil-gas coupling poly-generation method in the coal chemical engineering industry. The oil-gas coupling poly-generation method comprises the following steps of: treating and dividing coal tar into heavy oil fraction, crude phenol, dephenolized oil, crude naphthalene, naphthalene-removed oil and washing oil by virtue of a normal-pressure distillation system and a chemical-removing system; discharging the crude phenol and the washing oil; feeding the heavy oil fraction, the washing oil, the dephenolized oil and the naphthalene-removed oil to an oil-gas coupling system; treating the coal gas to obtain LPG (Liquefied Petroleum Gas), petrol, durene and dealkylation heavy oil by virtue of a methanol conversion system and an MTG (Methanol To Gasoline) system; discharging the LPG, the petrol and the durene; feeding the dealkylation heavy oil to the oil-gas coupling system and carrying out coupling hydrogenation treatment in the oil-gas coupling system to obtain naphtha and diesel oil. According to the oil-gas coupling poly-generation method in the coal chemical engineering industry disclosed by the invention, the tar and the coal gas are effectively coupled, so that the resource waste is avoided; the high-additional value oil and chemicals including phenol, naphthalene, aromatic hydrocarbon and the like are generated, so that the direct emission of coal gas and the car is prevente, and therefore, the environment pollution is reduced and the method is more friendly to the environment.

The invention provides a process for the preparation of hydrocarbons comprising the steps of:

• (a) contacting a mixture of carbon monoxide and hydrogen at an elevated temperature and pressure with a mixture of a methanol synthesis catalyst and a methanol conversion catalyst thereby forming C₅⁺ hydrocarbons;
• (b) separating at least part of the C₅⁺ hydrocarbons as obtained in step (a) into a light stream and a heavy durene-rich stream;
• (c) subjecting at least part of the heavy durene-rich stream to a hydrodealkylation treatment in the presence of hydrogen to obtain a stream of hydrocarbons having a reduced durene content; and
• (d) mixing at least part of the light stream as obtained in step (b) with at least part of the stream of hydrocarbons having a reduced durene content as obtained in step (c).

A method for preparing petroleum naphthalene from C10 heavy Aromatic Hydrocarbon material belongs to the preparation technical field of petroleum naphthalene, which comprises exchanging the heat of C10 heavy Aromatic Hydrocarbon material with low naphthalene with the light fraction distillate at the top of a first distillation column, leading the material into the distillation column to be distilled, exchanging the heat and condensing the light fraction at column top, feeding condensate into a reflux tank at column top, leading the top distillate as a first solvent via a pipeline, leading out rich durene solution from the first side pipeline of the first distillation column, separating out the light fraction distillate and the rich durene solution, leading the heavy fraction distillate at the column bottom into a second distillation column to be distilled, leading out the top distillate of the second distillation column as a second solvent via a pipeline, separating out the light and heavy fraction distillates in the second distillation column, leading out rich naphthalene solution from a second side pipeline of the second distillation column, cooling, crystallizing the rich naphthalene solution via a crystallization device, and separating crystallization mother liquor via a centrifugal separator, to obtain final product of petroleum naphthalene. The invention has few process, simple operation and low cost, while the whole preparation has no generation of three wastes.

The invention discloses a catalyst capable of being used for synthetizing benzenetetracarboxylic anhydride and a preparation method of the catalyst, and belongs to a catalyst technology. The catalyst comprises the main catalytic active components V and Ti; the weight ratio is (0.9 to 0.1) to (0.1 to 0.9); the total mass is 10-50% of that of an inert carrier; the total mass reference of the main catalyst is 1; the component P of a cocatalyst is 0.01-0.3; Nb is 0.01-1; and Sb is 0.01-0.3. The method comprises the following steps of: adding proper ammonium metavanadate to reflux and react in an oxalate solution; adding different cocatalysts and titanium dioxide to steep over the night; spraying prepared turbid liquid to a high-temperature spherical inert carrier; and heating and baking in a muffle furnace to obtain the catalyst. The catalyst disclosed by the invention has the advantages that the prepared material is abundant in source; use of toxic vanadium metal is reduced; the catalyst is used for synthesizing the benzenetetracarboxylic anhydride from durene air in a gas phase oxidation manner, and is good in performance; and the yield of the benzenetetracarboxylic anhydride can be effectively improved.

The invention discloses a system and a method for preparing durene by the utilization of toluene and methanol. The problems such as limited sources of raw materials, high cost of raw materials, low yield of durene, low purity of durene and the like existing in the durene preparation technologies in the prior art are solved. The prepared durene has high yield and high purity. The technical scheme comprises the following steps: preheating toluene and methanol and introducing the preheated toluene and methanol into an alkylation reactor, and reacting at the reaction temperature of 350-400 DEG C at the reaction pressure of 2.0-5.0 MPa at the mass space velocity of 1-5 h<-1> for the reaction retention time of 1-5 s by using an HZSM-5 molecular sieve catalyst as a reaction catalyst; removing moisture and dry gas by oil-water separation of the reaction liquid, removing toluene, mixed xylenes and mixed trimethylbenzenes by rectifying the oil phase, and cooling for crystallization so as to obtain pure durene.

The invention relates to a catalyst for synthesizing pyromellitic dianhydride from durene. The catalyst mainly overcomes the problem of low yield of the target product pyromellitic dianhydride due toa great number of side reactions in oxidation of durene in the prior art. According to the invention, an oxide catalyst is employed; the catalyst adopts alpha-Al2O3, silicon carbide, a ceramic ring ora mixture thereof as a carrier; and the active component of the catalyst is at least one selected from a group consisting of elemental vanadium, group-IVB elements, group-VIB elements and alkali metal elements. With such a technical scheme, the above technical problem is overcome, side reactions in oxidation of durene are reduced, and the yield of pyromellitic dianhydride is improved.

The invention provides a method for preparing durene from methanol and xylene. Xylene is mixed with a part of methanol; the mixture enters from a top main line into a reactor, and the rest methanol enters the reactor in a side-line multi-section feeding manner; the materials are converted into a mixed hydrocarbon component rich in durene under the conditions that the temperature is 250-400 DEG C and the pressure intensity is 0.5-2.0 MPa, the mixed hydrocarbon component is separated to obtain heavy aromatic hydrocarbon rich in durene, and through multi-stage freezing crystallization and centrifugal separation squeezing system, high-purity durene is obtained. Bed layer temperature rise during alkylation is controlled by adopting side line methanol multi-section feeding, reaction heat of an upper-section bed layer of the reactor is fully utilized to preserve heat of a middle-section bed layer and a tail-section bed layer, and a modified nano ZSM-5 molecular sieve catalyst is used for reducing the reaction temperature; xylene and mixed aromatic hydrocarbon thereof and methanol are continuously subjected to alkylation reaction for many times, so that the selectivity of durene in an oilphase product is improved. And the yield of durene is improved by fully utilizing reaction by-products.

The invention relates to a durene-poly-generation technological method and production system for preparing light hydrocarbon through methyl alcohol. The technological method is adopted for the production system. The technological method includes the steps that multiple moving bed synthesis reactors connected in series form a synthesis reaction system; the methyl alcohol or the water-contained methyl alcohol serves as raw materials and is mixed with circulating gas, then the mixture is introduced into the synthesis reaction system to be subjected to a catalysis reaction, and a reaction product containing the C1-C11 light hydrocarbon is generated; an oil phase in the reaction product is further separated to prepare gasoline blending components and the high-purity durene; the circulating gas serves as heat carriers of heat generated by the reaction, and the synthesis reaction temperature is controlled to control the component distribution of the synthesis reaction product and the yield of the target product to enable the mass ratio of the durene to the hydrocarbon in the reaction product to be larger than or equal to 10%. The system comprises the corresponding synthesis reaction system and the light hydrocarbon separating system. By means of the technological method and production system, continuous production of light hydrocarbon produced through the methyl alcohol and poly-production of the durene and the like is achieved, technological conditions are stable and easy to control, and product quality is good.

The invention relates to a catalyst for preparing pyromellitic dianhydride through durene gas phase oxidation. The catalyst mainly solves the problem that the existing durene gas phase oxidation reaction produces more by-products and leads pyromellitic dianhydride yield reduction. An oxide catalyst utilizes alpha-Al2O3, silicon carbide, a porcelain ring or a mixture thereof as a carrier, and an active component comprises at least one of a vanadium element, a lanthanum element, a nonmetal element and an alkaline-earth metal element. The catalyst solves the technical problem, reduces side reactions during the pyromellitic dianhydride synthesis and improves the yield of pyromellitic dianhydride.

The invention provides a method for preparing 4, 4'-dihydroxyl diphenyl sulfone. The method comprises the following steps: adding 2,6-naphthalene disulfonic acid in a mixed solvent of mesitylene and durene, and then preparing the 4, 4'-dihydroxyl diphenyl sulfone by sulfonation and dehydration reaction between phenol and concentrated sulfuric acid, wherein the 2,6-naphthalene disulfonic acid is a by-product separated from the production of 2,7-naphthalene disulfonic acid, low in price and rich in source; the mass ratio of the 2,6-naphthalene disulfonic acid to the concentrated sulfuric acid (density of 98%) is (0.03-0.15):1; the mass ratio of the solvent to the concentrated sulfuric acid is (1.85-2.48):1; the mass ratio of the phenol to the concentrated sulfuric acid is (1.89-2.03):1; in the solvent, the mass ratio of the mesitylene to durene is (2.8-4):1; and the time of reflux dehydration reaction is 6-10h. The material of the method is excellent in suspension, high in reaction temperature and beneficial to dehydration reaction and the yield of 4, 4'-dihydroxyl diphenyl sulfone is high.

The invention discloses a method for preparing catalysts for preparing benzenetetracarboxylic anhydride from durene by means of gas-phase catalytic oxidation. The catalysts comprise spray liquid and carriers. The spray liquid mainly comprises, by weight, 3-5 parts of ammonium metavanadate, 11.2-11.4 parts of oxalic acid, 0.2-0.4 part of diammonium hydrogen phosphate, 0.1-0.3 part of trisodium phosphate anhydrous, 0.18-0.2 part of antimony oxide, 1.1-1.3 parts of ammonium molybdate, 0.98-1 part of potassium hydroxide, 0.6-0.8 part of sodium dihydrogen phosphate, 0.18-0.2 part of potassium carbonate, 0.68-0.7 part of potassium dihydrogen phosphate, 1.16-1.18 parts of potassium phosphate and 8.6-8.8 parts of titanium dioxide powder; the carriers are 78.5-78.7 parts of porcelain rings. The method includes four steps of weighing, liquid preparing, spraying and calcining. The method has the advantages that the catalysts prepared by the aid of the method are good in activity, high in selectivity, low in hotspot reaction temperature and long in service life when applied, and partial energy consumption can be reduced when the catalysts are applied.