摘要:
The conversion of normal olefins such as n-butylenes can be converted to branched olefin species such as isobutylene by skeletal isomerization over zeolite-based catalysts having pore sizes of at least about 4.5 Angstroms and a pore structure characterized by intersecting 10-MR and 8 MR channels. The zeolite-based catalysts have sufficient acidity to catalyze the skeletal isomerization of normal olefins. The catalysts can be used to produce isoolefins for reaction with alcohols in integrated processes to produce alkyl tertiary alkyl ethers such as MTBE.
摘要:
The invention relates to a novel process for the synthesis of zeolites of the ferrisilicate type called ferrizeosilites, to the products obtained by this process as well as their uses. Ferrizeosilite according to the invention is characterized by (a) a chemical formula close to the following:M.sub.2/n O, Fe.sub.2 O.sub.3, x SiO.sub.2whereM represents a proton and/or a metal cationn is the valence of said cationx is a number between 40 and 1000(b) an x-ray diffraction diagram, and (c) a fluorine content between about 0.01% and 16% by weight. Uses are in processes for the conversion of methanol into hydrocarbons, alkylation of toluene with methanol and catalytic cracking of hydrocarbons.
摘要:
Dienes are prepared by dehydration of aldehydes at elevated temperatures by a method in which the dehydration is carried out using a zeolite as a catalyst.
摘要:
An improved process for the preparation of certain crystalline iron silicates particularly suitable for converting acyclic oxygen-containing hydrocarbons into aromatic hydrocarbons wherein use of high silicon content compounds together with certain amines results in silicates having unexpected catalytic stability.
摘要:
Provided are zeolite catalysts that allow reactions to proceed at temperatures as low as possible when lower olefins are produced from hydrocarbon feedstocks with low boiling points such as light naphtha, make it possible to make propylene yield higher than ethylene yield in the production of lower olefins, and have long lifetime.The zeolite catalysts are used in the production of lower olefins from hydrocarbon feedstocks with low boiling points such as light naphtha. The zeolite catalysts are MFI-type crystalline aluminosilicates containing iron atoms and have molar ratios of iron atoms to total moles of iron atoms and aluminum atoms in the range from 0.4 to 0.7. The use of the zeolite catalysts make it possible to increase propylene yield, to lower reaction temperatures, and to extend catalyst lifetime.
摘要:
A process for converting an oxygenate feed to high purity olefins such as polymer-grade propylene (C.sub.3.sup.0 /C.sub.3.sup.= .ltoreq.0.05) at a temperature of about 450.degree. C. (842.degree. F.), using a molecular sieve catalyst having a high preselected Si/Al.sub.2 ratio (such as ZSM-5, ZSM-48) or a preselected Si/Fe.sub.2 ratio (such as FeZSM-5), or SAPO-34.
摘要:
This invention relates to molecular sieve compositions and processes for using the molecular sieves. The molecular sieves have a three-dimensional microporous crystalline framework structure of tetrahedral oxide units of AlO.sub.2, SiO.sub.2, TiO.sub.2 and/or FeO.sub.2. These molecular sieves can be prepared by contacting a starting zeolite with a solution or slurry of a fluoro salt of titanium and/or iron under effective process conditions to extract aluminum from the zeolite framework and substitute titanium and/or iron. The molecular sieves can be used as catalysts in hydrocarbon conversion processes and other processes.
摘要:
A catalyst composition which contains at least one metal from Group 2b and at least one metal from Group 6b of the Periodic Table of the Elements or compounds thereof and a crystalline aluminum silicate which is obtained by crystallizing an aqueous alkaline starting mixture comprising at least one silicon compound, at least one aluminum compound, at least one compound of a metal from Group 1a of the Periodic Table of the Elements (MX) and organic nitrogen compounds at an elevated temperature until said crystalline aluminum silicate is formed and subsequently separating crystalline aluminum silicate from the mother liquor, in which starting mixture the compounds are present in the following molar ratios:RN: R.sub.4 NY=1-1000,SiO.sub.2 : R.sub.4 NY=10-5000,SiO.sub.2 : Al.sub.2 O.sub.3 =50-300,SiO.sub.2 : MX
摘要:
A process is disclosed for oligomerizing light olefins or mixtures thereof, which consists in reacting said olefins, possibly diluted with an inert gas, by means of synthetic zeolites containing oxides of silicon, titanium and iron, having, in their calcined and anhydrous state, the following empirical formula:pHFeO.sub.2. qTiO.sub.2.SiO.sub.2,wherein p has a value larger than zero and smaller than, or equal to, 0.050 and g has a value larger than zero and smaller than, or equal to 0.025, and the H.sup.+ of HFeO.sub.2 can be at least partially substitutable or substituted with cations.
摘要:
Novel crystalline silicates which in dehydrated form have the composition in terms of moles of the oxides: (1.0.+-.0.3)(R).sub.2/n O.[aFe.sub.2 O.sub.3.bAl.sub.2 O.sub.3.cGa.sub.2 O.sub.3.y(dSiO.sub.2.eGeO.sub.2)], wherein R is one or more mono- or bivalent cations and a, b, c, d, e, y and n are as defined hereinafter are disclosed. The thermally stable silicates are suitably employed as extracting agents, drying agents, ion exchange agents, catalysts and catalyst carriers.