113results about "Preparation from carbon monoxide and oxygen" patented technology

An environmentally beneficial method of producing methanol from varied sources of carbon dioxide including flue gases of fossil fuel burning powerplants, industrial exhaust gases or the atmosphere itself. Converting carbon dioxide by electrochemical reduction produces formic acid acid and some formaldehyde and methanol mixtures. The formic acid can be used as source of carbon as well as hydrogen to produce methanol, dimethyl ether and other products.

A process for the preparation of an aromatic carbonate is disclosed. The process entails reacting in the presence of a catalyst system an aromatic hydroxy compound with carbon monoxide and oxygen, and optionally in one or more solvents to produce a liquid phase. At least a portion of the liquid phase is subjected to a treatment to obtain a treated liquid phase. The treatment entails at least one of (a) heating to a temperature that is at most mean reaction temperature without passing oxygen thereto, and (b) adding one or more protic compounds thereto, and (c) passing through it one or more inert or reducing gases. Solid metallic catalyst constituents are then separated from the treated liquid phase.

Unexpected corrosion of downstream sections of a dialkyl carbonate manufacturing apparatus has been traced to alkyl chloroformate impurities, which slowly decompose to yield hydrochloric acid. An improved process and apparatus for dialkyl carbonate synthesis reduce corrosion by physically removing or chemically decomposing the alkyl chloroformate impurities within the corrosion-resistant upstream sections of the apparatus.

The invention discloses a preparation method of a high-efficiency nitrogen-doped carbon nanotube. The preparation method comprises the following steps: adding a multiwalled carbon nanotube into a nitric acid solution; closing the solution in an autoclave; pressurizing to 0.4 to 1.0 MPa, and stirring; then heating to 120 to 200 DEG C and keeping for 1 to 4 hours; finally, cooling to room temperature by the autoclave; washing to neutral and carrying out suction filtration and drying; mixing the carbon nanotube with a melamine solid according to the mass ratio being 1 to (1 to 4), and uniformly grinding by using mortar; and carrying out high-temperature sintering in nitrogen, washing to neutral and then drying to obtain the nitrogen-doped carbon nanotube. The nitrogen doping amount of the high-efficiency nitrogen-doped carbon nanotube disclosed by the invention is 4.6 to 10.3 weight percent.

Unexpected corrosion of downstream sections of a dialkyl carbonate manufacturing apparatus has been traced to alkyl chloroformate impurities, which slowly decompose to yield hydrochloric acid. An improved process and apparatus for dialkyl carbonate synthesis reduce corrosion by physically removing or chemically decomposing the alkyl chloroformate impurities within the corrosion-resistant upstream sections of the apparatus.

Unexpected corrosion of downstream sections of a dialkyl carbonate manufacturing apparatus has been traced to alkyl chloroformate impurities, which slowly decompose to yield hydrochloric acid. An improved process and apparatus for dialkyl carbonate synthesis reduce corrosion by physically removing or chemically decomposing the alkyl chloroformate impurities within the corrosion-resistant upstream sections of the apparatus.

The invention relates to a silicon dioxide loaded copper-dipyridyl catalyst and its preparation method. The catalyst carrier is dipyridyl modified silicon dioxide, and the active component is copper; the mole ratio of the dipyridyl modified silicon dioxide to copper is 0.3-3.5: 1 and weight of Cu of catalyst is 4-6 wt% of the total weight of catalyst. In application of preparing dimethyl carbonate, the selectivity of dimethyl carbonate reaches 99.9%, and yield of dimethyl carbonate exceeds 53%.

The invention discloses a catalyst for synthesizing dimethyl carbonate by methanol liquid-phase oxidative carbonylation and methods. The catalyst comprises a copper halide and an ionic liquid; the mass ratio of the copper halide to the ionic liquid is 1:(1-10); a cation of the ionic liquid is an imidazole cation, a quaternary ammonium salt cation or a pyridine cation; and an anion of the ionic liquid is a halogen ion. The catalyst disclosed by the invention has relatively high methanol conversion ratio and high dimethyl carbonate selectivity and has an industrial application prospect. In addition, due to the addition of the ionic liquid, corrosion to stainless steel reaction equipment can be relieved.

The invention relates to an intelligent reaction system and process for synthesizing dimethyl carbonate through liquid-phase oxidative carbonylation of methanol. The intelligent reaction system comprises a reaction tower, a buffer tank, micro-interface generators and an intelligent control unit. Oxygen and carbon monoxide are crushed to form micron-scale bubbles, so the reaction rate of oxygen andcarbon monoxide with liquid-phase methanol is increased; meanwhile, a gas-liquid emulsion is conveyed back to a reaction area through a second micro-interface generator for opposite impacting with agas-liquid emulsion output by a first micro-interface generator, and therefore, the retention time of the micron-scale bubbles in the reaction area is prolonged, gas and liquid phases are subjected toa secondary reaction, and the conversion rate of liquid-phase methanol is increased; and through the intelligent control unit, a worker can know the real-time situation of all data sent back by an intelligent sensing module at any time through a mobile device, and the inner temperature and the inner pressure of the whole reaction tower can be accurately controlled by changing preset values, so reaction efficiency is further improved.

The invention discloses a preparation method of a Cu nanoparticles-embedded ordered mesoporous carbon catalyst and belongs to the field of chemical heterogeneous catalysis. The preparation method comprises the following steps: Step 1, template mesoporous silica material SBA-15 filling-rolling over; Step 2, carbonization; and Step 3, silica removal. The process of template mesoporous silica material SBA-15 filling-rolling over comprises impregnation, dispersion, drying, pre-carbonization and single repetitive operation. The problem that catalytic activity of a catalyst will decrease with the reaction process is solved. The prepared chloride-free copper-based catalyst of the invention is a nanoscale catalyst with 5-25nm copper particles embedded in pores of and on the surface of the ordered mesoporous carbon. Dispersity is good, and migration and agglomeration are not easy to occur in the reaction process. The catalyst has high reaction activity and good stability when used in an atmospheric continuous fixed bed for methanol gaseous oxidative carbonylation for synthesis of dimethyl carbonate.

The present invention is directed to a method for reactivating a deactivated carbonylation catalyst composition previously used in a carbonylation reaction involving an aromatic hydroxy compound, carbon monoxide and oxygen, such that the reactivated catalyst composition is effective at carbonylating an aromatic hydroxy compound in a subsequent oxidative carbonylation reaction.

The invention discloses an efficient and safe method for synthesizing carbonic ester by using oxidative carbonyl. The method comprises the steps of oxidative glycosylation reaction, flash separation, gas-liquid separation and product separation. The method can be used for overcoming the defects of heterogeneous catalytic system, complex process, poor recyclability and potential safety hazard of reaction process in the prior art; a novel process device is adopted; the feeding mole ratio of carbon monoxide (CO) to oxygen (O2) can be controlled; CO and O2 are taken as the reaction raw material gases; the catalyst solution is recyclable; a catalyst system applied to the reaction is a catalyst solution prepared from a solvent and a complex which is formed by homogeneous active components and ligands. The method has the advantages that the process is efficient, safe and simple, and the catalyst solution is easily recyclable; and the method has a good prospect of industrial application.

The present invention relates to a process for producing diaryl carbonates, which is to synthesize diaryl carbonates by oxidative carbonylation of phenols with carbon monoxide and oxygen, and in particular, to synthesize diphenyl carbonate from phenol. The present invention is characterized in that a catalytic system comprising a metal halide catalyst and one or more cocatalysts of nitrogenous heterocyclic compounds is used to increase the convertibility, selectivity and yield of this catalytic reaction.

The present invention is directed to a method for reactivating a deactivated carbonylation catalyst composition previously used in a carbonylation reaction involving an aromatic hydroxy compound, carbon monoxide and oxygen, so that the re-activated catalyst composition is effective at carbonylating an aromatic hydroxy compound in a subsequent oxidative carbonylation reaction.

The invention relates to a pyridine coordinated copper heterogeneous catalyst and a preparation method thereof. The carrier of the catalyst is pyridine modified silicon dioxide, and the active component is copper; the molar ratio of the pyridine modified silicon dioxide to the copper is (0.5-1.9):1; in the catalyst, the Cu accounts for 4 to 6 percent of the total weight of the catalyst. In application to preparation of dimethyl carbonate, the selectivity of the dimethyl carbonate reaches 99.9 percent and the yield of the dimethyl carbonate exceeds 54 percent.

A method of increasing the amount of diphenylcarbonate produced per amount of catalyst consumed in a phenol carbonylation process is described. Phenolic carbonylation produces water as a reaction product which reduces the turnover number (TON) of the catalyst. A mixture of a phenolic precursor, a base containing catalyst and co-catalyst components and at least one chemical additive comprising a halide or hydroxide of alkali metal or alkaline earth metal when carbonylated together under specific conditions increases the turnover number (TON) and water resistivity of a palladium catalyst. The metal halide likely makes the catalyst less susceptible to degradation by water hence increasing the reaction yield per weight of catalyst consumed.

The invention relates to a catalyst for oxidative carbonylation of ethanol to synthesize diethyl carbonate and a preparation method thereof, belonging to the technical field of oxidative carbonylation of alcohol and the gas phase synthesis catalytic technology of diethyl carbonate. The catalyst consists of uniformly distributed Cu ions, Pd ion active sites and silica carrier. The invention has the advantages that the relative distribution structure of the Cu ion and the Pd ion center is adjustable, and the electronic structure of the Cu and Pd centers is adjustable. The catalyst is used in the oxidative carbonylation of ethanol, a miniature fixed bed reactor is adopted and the conditions are mild. The catalyst has high activity and high selectivity to diethyl carbonate. Under stable conditions, the space-time conversion rate of ethanol reaches 298 mg.g/1.h-1. The selectivity of diethyl carbonate is 85.1%.

A technology for synthesizing dimethyl carbonate adopts a two-tower continuous reaction, and comprises the following steps: a raw material liquid methanol is fed from the upper part of a gas and liquid distributor of a first reactor, flows out of the gas and liquid distributor and enters the reaction section of a reactor, a raw material gas CO is introduced to the first reactor from the bottom ofthe reaction section of the reactor, O2 is divided into 2-5 passages, O2 in the 2-5 passages except one is distributed in the reaction section of the reactor, a reaction is continuously carried out under the action of a catalyst in the reaction section to generate dimethyl carbonate, a formed mixed liquid A flows into the water separation section of the first reactor, methanol and dimethyl carbonate in the mixed A go through a bottom hydrophobic membrane and continuously downwards flow into a tower bottom to form a mixed liquid B, water permeates a surrounding hydrophilic membrane, and then iscollected and discharged, the mixed liquid B in the bottom of the first reactor enters a second reactor, a crude product is extracted from the bottom of the second reactor, and non-condensable gasesCO, O2 and CO2 obtained after the reactions in the first reactor and the second reactor are discharged from the top of the reactors. The technology has the advantages of simple process, high methanolconversion rate and low energy consumption.