3969 results about "Dimethyl ether" patented technology

The invention relates to a process for the production of acetic acid by carbonylation of methanol, and reactive derivatives thereof, in a reaction mixture using a rhodium-based catalyst in low water conditions. The process is used to achieve reaction rates of at least 15 g mol/l/hr. The high rate reactions proceed at water concentrations of less than 2.0 wt. %. Under certain conditions, the water concentration in the reaction mixture of the process is maintained at a desired concentration by at least one process step including adding a compound such as methyl acetate, dimethyl ether, acetic anhydride, or mixtures of these compounds to the reaction system. The process step of adding the components to the reaction mixture may be combined with other process steps for controlling water concentrations in reaction mixtures for the carbonylation of methanol.

The invention relates to a system and a process for preparing aromatic hydrocarbon by converting methanol or dimethyl ether and belongs to the technical field of aromatic hydrocarbon production. The methanol or the dimethyl ether serving as a raw material firstly reacts in an aromatization reactor; a reaction product is separated; H2, methane, mixed C8 aromatic hydrocarbon and partial C9s + hydrocarbons serving as products are output from the system; and C2+ non-aromatic hydrocarbon and aromatic hydrocarbons except the mixed C8 aromatic hydrocarbon and the partial C9s + hydrocarbons are take as a circular material flow and return to corresponding reactors for further aromatization reaction. By separating and recycling the product obtained in the process of aromizing the methanol or the dimethyl ether, the system and the process improve the yield and selectivity of the aromatic hydrocarbon; and moreover, the process is flexible, and target products can be changed according to market demands.

Improved processing for the production of light olefins via oxygenate conversion processing is provided. Synthesis gas conversion such as to produce an effluent including at least methanol can be integrated with oxygenate conversion processing such as to produce an oxygenate conversion reactor effluent including at least light olefins and dimethyl ether. At least a portion of the oxygenate conversion reactor effluent can be contacted with such produced methanol to effect recovery of dimethyl ether from the oxygenate conversion reactor effluent.

There is provided a process for converting methanol and/or dimethyl ether to a product containing C2 to C4 olefins which comprises the step of contacting a feed which contains methanol and/or dimethyl ether with a catalyst comprising a porous crystalline material, said contacting step being conducted in the presence of an aromatic compound under conversion conditions including a temperature of 350 DEG C. to 480 DEG C. and a methanol partial pressure in excess of 10 psia (70 kPa), said porous crystalline material having a pore size greater than the critical diameter of the aromatic compound and the aromatic compound being capable of alkylation by the methanol and/or dimethyl ether under said conversion conditions.

There is provided a catalyst and a process for converting methanol or dimethyl ether to a product containing C2 to C4 olefins. The catalyst comprises a porous crystalline material having a Diffusion Parameter for 2,2-dimethylbutane of about 0.1-20 sec-1 when measured at a temperature of 120 DEG C. and a 2,2-dimethylbutane pressure of 60 torr (8 kPa). In addition, the catalyst is characterized by a hydrothermal stability such that, after steaming the catalyst at 1025 DEG C. for 45 minutes in 1 atmosphere steam, the catalyst exhibits a methanol conversion activity of at least 50% when contacted with methanol at a methanol partial pressure of 1 atmosphere, a temperature of 430 DEG C. and 0.5 WHSV. The porous crystalline material is preferably a medium-pore zeolite, particularly ZSM-5, which contains phosphorus and has been severely steamed at a temperature of at least 950 DEG C.

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.

Improved processing for the production of light olefins is provided involving synthesis gas conversion to form an effluent including product dimethyl ether, subsequent separation of the product dimethyl ether and conversion thereof to the desired light olefins. The synthesis gas conversion effluent may also desirably include methanol and at least a portion of such methanol may be employed to effect the separation of the product dimethyl ether.

A process for preparing low-carbon olefin from methanol or dimethyl ether includes loading its raw material and silicon aluminium phosphate (SAPO34) molecular sieve as catalyst into gas-solid parallel down-flowing fluidized bed reactor, super-short contact, reaction, fast gas-solid separation to separating resultant from catalyst to prevent secondary reaction, and regerating catalyst for cyclic use. Its advantages include high output rate (93%), high conversion rate of raw material, and less by-product.

An environmentally clean dual fuel for an internal combustion engine, comprising acetylene as a primary fuel and a combustible fuel, such as one or more fluids selected from an alcohol such as ethanol, methanol or any other alcohol or alcohols from the group comprising C1-C20 carbon chains, ethers such as from the group comprising dimethyl ether, diethyl ether, methyl t-butyl ether, ethyl t-butyl ether, t-amyl methyl ether, di-isopropyl ether and the like, low-molecular-weight esters such as from the group comprising methyl formate, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate and the like, or other suitable combustible fluid such as mineral spirits and the like, as a secondary fuel for operatively preventing early ignition and knock arising from the primary fuel. The dual fuel, internal combustion system, which generally utilizes a two-stage process for start-up and operation and can be operated with air- or liquid-cooling, is environmentally clean with hydrocarbon, CO, NOx, and SOx emissions substantially eliminated.

This invention provides processes for forming light olefins from methanol and/or from syngas through a dimethyl ether intermediate. Specifically, the invention is to converting methanol and/or syngas to dimethyl ether and water in the presence of a first catalyst, preferably comprising γ-alumina, and converting the dimethyl ether to light olefins and water in the presence of a second catalyst, preferably a molecular sieve catalyst composition.

A process for producing high octane fuel from carbon dioxide and water is disclosed. The feedstock for the production line is industrial carbon dioxide and water, which may be of lower quality. The end product can be high octane gasoline, high cetane diesel or other liquid hydrocarbon mixtures suitable for driving conventional combustion engines or hydrocarbons suitable for further industrial processing or commercial use. Products, such as dimethyl ether or methanol may also be withdrawn from the production line. The process is emission free and reprocesses all hydrocarbons not suitable for liquid fuel to form high octane products. The heat generated by exothermic reactions in the process is fully utilizes as is the heat produced in the reprocessing of hydrocarbons not suitable for liquid fuel.

The present invention relates to a method of producing methanol from a methane source by oxidizing methane under conditions sufficient to a mixture of methanol and formaldehyde while minimizing the formation of formic acid and carbon dioxide. The oxidation step is followed by treatment step in which formaldehyde is converted into methanol and formic acid which itself can further be converted into methanol via catalytic hydrogenation of intermediately formed methyl formate.

The disclosed invention relates to a process for conducting an equilibrium limited chemical reaction in a microchannel reactor. The process involves the use of active heat exchange and is suitable for conducting exothermic and endothermic reactions. The process is particularly suitable for synthesizing methanol and dimethyl ether.

A catalyst for an integrated supported carbon modular sieve comprises an integrated beehive cordierite, a carbon-nano tube and an HZSM-5 modular sieve, wherein the carbon-nano tube takes 7-20 proportions, HZSM-5 takes 10-30 proportions, and cordierite tales 60-80 proportions. The preparation method is that: carbon-nano tube is produced in situ on the integrated beehive cordierite by using chemical vapor deposition firstly, and the carbon-nano tube is taken as carrier, then the ZSM-5 modular sieve is developed on the carrier by using a secondary growth method. The catalyst for an integrated supported carbon-modular sieve can be used for the gas-phase synthesis of dimethyl ether DME by the dehydration of methanol.

The present invention is directed to a method of making a ligand which can be used to form an ansa-metallocene. Further, the present invention is directed to a method of making the ansa-metallocene. In both methods the process steps employed to form the ligand are conducted in the presence of tetrahydrofuran, a substituted tetrahydrofuran, tetrahydropyran, a substituted tetrahydropyran or ethylene glycol dimethyl ether.

The invention provides a method for continuous production of polyformaldehyde dimethyl ether. The method is characterized by comprising the following steps: a) feeding dimethoxymethane and hot-melted paraformaldehyde into a fixed bed reactor and adopting an acidic resin catalyst, so as to prepare polyformaldehyde dimethyl ether (DMM3-8), wherein the reaction temperature is 120-180 DEG C and the pressure is 0.1-10 MPa; b) cooling the reaction product, and then performing adsorptive separation through a dehydrating tower, so as to obtain polyformaldehyde dimethyl ether of which most water, cytidine glycol and hemiacetal are desorbed; c) feeding the polyformaldehyde dimethyl ether subjected to desorption into a distillation tower for separation, wherein most of a low-boiling component (dimethoxymethane (DMM)), poly-di-formaldehyde dimethyl ether (DMM2), a by-product (methanol) and triformol are extracted first, and then the materials in a tower kettle are fed into a rectifying tower in the next step, so as to extract the rest of the DMM2 and the triformol; and d) returning the low-boiling component (dimethoxymethane (DMM)), the methanol, the DMM2 and the triformol, which are evaporated out by the distillation tower and the rectifying tower in the last step, into the fixed bed reactor to continue to react to prepare polyformaldehyde dimethyl ether.

The present invention relates to a method for synthesizing dimethyl ether by high-effectively cleanly utilizing biomass. It utilizes the gasified gas produced by catalytic gasification of biomass air-water vapor, and makes the gasified gas undergo the process of methane reformation to prepare synthetic gas, and utilizes the synthetic gas to directly synthesize clean fuel dimethyl ether.