摘要:
This invention is directed to a molecular sieve composition or a catalyst containing molecular sieve which has a relatively high residual silica index, preferably at least about 1.5. The molecular sieve or catalyst can be made by contacting a template-containing molecular sieve with a silicon containing material having an average kinetic diameter that is larger than the average pore diameter of the sieve or catalyst, and heating to leave residual silica at the sieve or catalyst surface. The molecular sieve or catalyst is particularly effective in making an olefin product from an oxygenate feedstock.
摘要:
Disclosed is a method and system for reducing the formation of metal catalyzed side-reaction byproducts formed in the feed vaporization and introduction system of a methanol to olefin reactor system by forming and/or coating one or more of the heating devices, feed lines or feed introduction nozzles of/with a material that is resistant to the formation of metal catalyzed side reaction byproducts. The invention also may include monitoring and/or maintaining the temperature of at least a portion of the feed vaporization and introduction system and/or of the feedstock contained therein below about 400° C., 350° C., 300° C., 250° C., 200° C. or below about 150° C. The temperature can be maintained in the desired range by jacketing at least a portion of the feed vaporization and introduction system, such as at least a portion of the feed introduction nozzle, with a thermally insulating material or by implementing a cooling system.
摘要:
The present invention provides a method for converting a feed containing oxygenates to olefins and comprises the following steps: providing a feed including an oxygenate; contacting the feed in a reactor apparatus with a catalyst including a molecular sieve, the contacting taking place under conditions effective to convert the oxygenate to a product including a light olefin, the conditions including a gas superficial velocity of at least two meters per second at least one point in the reaction zone; and recirculating a first portion of the catalyst to recontact the feed.
摘要:
A method for converting oxygenates to light olefins. The method comprises contacting, in a reactor, a feedstock comprising oxygenates with a molecular sieve catalyst under conditions effective to convert the feedstock to a product including light olefins and by-products, the contacting causing carbonaceous deposits to form on at least a portion of the molecular sieve catalyst producing deactivated catalyst; removing a portion of the deactivated catalyst from the reactor; regenerating the portion of the deactivated catalyst under conditions effective to remove at least a portion of the carbonaceous deposits from the deactivated catalyst to form an at least partially regenerated catalyst; exposing at least a portion of the at least partially regenerated catalyst to at least a portion of the by-products to selectivate the portion of the at least partially regenerated catalyst to form light olefins; and contacting the selectivated portion of the at least partially regenerated catalyst with the feedstock to form the product.
摘要:
The invention concerns a method for reactive separation of mixtures containing hydrocarbons and oxygenated hydrocarbons, by contacting a mixture of hydrocarbons such as C.sub.2 to C.sub.26 hydrocarbons and mixtures thereof and oxygenated hydrocarbons, such as C.sub.2 to C.sub.40 oxygenated hydrocarbons and mixtures thereof to form a mixture of hydrocarbons and lower molecular weight oxygenated hydrocarbons and heating the mixture in water at temperature typically from about and pressure sufficient to cleave the oxygenated hydrocarbons to lower molecular weight products to form a liquid layer containing water soluble reaction products and an organic layer containing primarily hydrocarbons.
摘要:
The present invention provides for a simplified process for converting ethers into their corresponding alcohols comprising forming an aqueous mixture of the ether and at least about 50% by weight water and heating the mixture under autogeneous pressure at a temperature of from about 250.degree. to 450.degree. C., more preferably from about 250.degree. C. up to the critical temperature of water which is about 374.degree. C. Heating is continued for a period of time sufficient to convert at least about 20% by weight of the ether, usually from about 5 up to about 120 minutes, depending on temperature and the amount of water present, and the identity of the starting ether feedstock.The process may be characterized as an aquathermolysis reaction wherein the reaction proceeds in water primarily through ionic routes rather than through free radical routes. Accordingly, relatively high conversion rates and good yields of alcohol and other reaction by-products may be obtained without the necessity of using a catalyst in the process.