摘要:
A method for converting starting material to olefins comprising contacting the starting material with a small pore non-zeolitic molecular sieve catalyst under effective conditions to produce olefins, wherein the non-zeolitic molecular sieve has been prepared in-situ or modified after synthesis by incorporation using an alkaline earth metal compound, wherein the alkaline earth metal ion is selected from the group consisting of strontium, calcium, barium, and mixtures thereof.
摘要:
The addition of a small amount of a second epoxide to the copolymerization of ethylene oxide or propylene oxide with carbon dioxide can give a melt processable polyalkylene carbonate terpolymer which can be processed without extensive thermal decomposition. This invention has particular utility in thermoplastic applications such as injection molding, blow molding, and film manufacture.
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 at least one point in the reaction zone; and recirculating a first portion of the catalyst to recontact the feed.
摘要:
Mixed vanadium-titanium-tin oxides catalysts having intrinsic surface areas before surface modification, greater than about 40 m.sup.2 /gram are disclosed. These catalysts are suitable for use in the preparation of acetic acid by gas-phase oxidation of butenes.
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:
Discrete, non-agglomerating particles of polyalkylene carbonate are produced by solvent/non-solvent precipitation using certain solvent/non-solvent systems. The free-flowing particles obtaine are from 30 to 3000 microns in diameter and are suitable for use in a variety of applications, particularly the preparation of foamed articles.
摘要:
The evaporative casting of molten metals has been shown to produce castings having smooth surfaces without any sign of carbon deposits thereon by using a terpolymer polycarbonate prepared from cyclopentene oxide or cyclohexene oxide, ethylene oxide, propylene oxide, or butylene oxide, and carbon dioxide in making patterns for the lost foam casting process.
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; and recirculating a first portion of the catalyst to recontact the feed.
摘要:
This invention is directed to a molecular sieve having acid catalyst sites and a method of maintaining the acid catalyst sites of a template-containing silicoaluminophosphate molecular sieve. The method comprises providing a template-containing silicoaluminophosphate molecular sieve and heating the molecular sieve in an oxygen depleted environment under conditions effective to maintain or preserve the number of acid catalyst sites. The heated molecular sieve exhibits at least one peak in the infrared region in a range of from 3630 cm−1 to 3580 cm−1. Preferably, the heated molecular sieve exhibits a combined peak area in the 3630 cm−1 to 3580 cm−1 range of at least 10% of a total peak area of all peaks in an infrared region between 4000 cm−1 to 3400 cm−1.
摘要:
This invention is directed to a molecular sieve having acid catalyst sites and a method of maintaining the acid catalyst sites of a template-containing silicoaluminophosphate molecular sieve. The method comprises providing a template-containing silicoaluminophosphate molecular sieve and heating the molecular sieve in an oxygen depleted environment under conditions effective to maintain or preserve the number of acid catalyst sites. The heated molecular sieve exhibits at least one peak in the infrared region in a range of from 3630 cm−1 to 3580 cm−1. Preferably, the heated molecular sieve exhibits a combined peak area in the 3630 cm−1 to 3580 cm−1 range of at least 10% of a total peak area of all peaks in an infrared region between 4000 cm−1 to 3400 cm−1.