摘要:
The present invention discloses a high stability rare earth zeolite Y with high rare earth and the preparation process thereof, which zeolite has a content of rare earth of 4-15 wt %, a unit cell constant of 2.450-2.458 nm, a differential thermal collapsed temperature of 1000-1056null C., a silica to alumina ratio of 8.3-8.8, and a content of sodium oxide less than 1.0 wt %. Said zeolite is prepared by drying a rare earth-containing zeolite Y, introducing gaseous silicon tetrachloride carried by dry air and reacting at a temperature of 150-600null C. for 10 min to 6 h. then purging with dry air and washing with de-cationized water to remove the soluble by-products. The rare earth zeolite Y possesses high activity and selectivity for cracking the heavy oils, high activity for hydrogen transfer, has good coke selectivity, can effectively increase the yield of light oils, and improve the quality of gasoline and thus can directly serve as an active component for preparing various hydrocarbon cracking catalysts.
摘要:
A zeolite A or an A/X mixture having an LCC>70 g liquid/100 g zeolite (hydrated) and a cold water CER>200 mg CaCO3/gram anhydrous zeolite (hydrated). The zeolite product may have a crystal size of 0.1-0.7 microns, a bulk density of 0.19-0.37 g/ml, and a median particle size of 1-5 microns. A process for making zeolite A or A/X mixtures is also claimed, including mixing a sodium silicate solution, a sodium aluminate solution, and an amorphous aluminosilicate initiator gel in a mixing vessel to create an aluminosilicate synthesis gel, and crystallizing the aluminosilicate synthesis gel to form zeolite crystals. The sodium aluminate solution may be added gradually to at least the sodium silicate solution at a rate of about 1-5% of the total batch alumina per minute, and/or a percentage of the total batch alumina may be added as alumina trihydrate (ATH) powder. The amount of total batch alumina added as an undissolved source of soluble alumina and the presence or absence of initiator or nullseednull gel determines whether the resulting zeolite product is an A/X mixture or only zeolite A. A process to augment the yield of a synthesis mixture is also claimed, comprising providing undissolved alumina in substantial excess of stoichiometric requirements in a primary crystallization step, yielding a slurry of crystalline zeolite A in an alumina-enriched mother liquor, and then adding soluble silicate to initiate a second stage of very rapid crystallization. Detergents containing zeolites of this invention are claimed.
摘要:
The present invention relates to an improved process for obtaining sodium silicate alkali solution depleted of sodium salt and enriched in silica from a mother liquor recovered after isolation of molecular sieves and more particularly, the present invention relates to a process for recycling mother liquor obtained after the isolation of molecular sieves for the preparation of fresh molecular sieves or as a binder for producing Fluid Catalytic Cracking (FCC) catalyst.
摘要:
The present invention is directed to certain catalyst compositions and processes that are capable of reducing sulfur compounds normally found as part of the gasoline fraction streams of fluid catalytic cracking processes. The present invention requires an equilibrium cracking catalyst composition comprises at least one Y-type zeolite having kinetic conversion activity of at least about 3 in combination with a Lewis acid containing alumina composite present in at least 50 weight percent of the composition. The resultant equilibrium catalyst composition has a kinetic conversion activity of at least about 2.
摘要:
Applicant has developed an improved adsorbent useful in removing contaminants from various hydrocarbon streams. The adsorbent contains a zeolite, an alumina and a metal component. The metal component (Madd) is present in an amount at least 10 mole % the stoichiometric amount of metal (M) (expressed as the oxide) needed to balance the negative charge of the zeolite lattice. In a specific application an adsorbent comprising zeolite X, alumina and sodium is used to purify an ethylene stream in order to remove CO2, H2S, methanol, and other Snull and Onull containing compounds.
摘要:
A molecular sieve is made by reacting an ammonium-exchanged low silica X-type zeolite precursor with lithium hydroxide, at a pressure of about 200 millibar or less, and at a temperature of about 60null or less. The zeolite precursor is preferably an X-type zeolite, in which the silicon to aluminum atomic ratio is less than about 1.02. The lithium is provided in an amount which is stoichiometrically equivalent to the amount of ammonium present. The molecular sieve is especially useful in separating air into components using PSA or VPSA processes, and has improved productivity and yield as compared with materials of the prior art. The advantages of the molecular sieve enable it to be provided in the form of beads having relatively large diameter, which reduces the pressure drop across the adsorber bed, and reduces required energy consumption.
摘要:
A zeolite of the faujasite structure having a silica to alumina molar ratio (bulk) of greater than about 13, a unit cell size in the range of from 24.10 to 24.40 null, and a surface area of at least about 875 m2/g as measured by the BET method and ASTM D4365-95 with nitrogen adsorption at p/po values of 0.02, 0.03 and 0.04, is prepared by a combination of hydrothermal and dealumination techniques, and finds use as, for example, an adsorbent for polar and non-polar materials.
摘要:
A fluid catalytic cracking catalyst made from microspheres that initially contain kaolin, a dispersible boehmite alumina and a sodium silicate or silica sol binder. The kaolin portion contains hydrous kaolin and a particular kaolin which has been calcined through its characteristic exotherm and which produces a catalyst having a novel morphology comprising a macroporous matrix and crystallized zeolite freely coating the walls of the pores of the matrix. Calcination of the hydrous kaolin to metakaolin and formation of in-situ zeolite by treatment with sodium silicate yields a catalyst containing Y-faujasite and transforms the dispersible boehmite into a transitional alumina. The catalyst can be used to crack resid or resid-containing feeds as the alumina phase formed from the dispersible boehmite passivates nickel and vanadium contaminants.
摘要:
Zeolite microsphere FCC catalysts having a novel morphology comprising a macroporous matrix and crystallized zeolite freely coating the walls of the pores of the matrix. The catalysts are formed from microspheres containing a metakaolin and kaolin calcined through its exotherm, the latter calcined kaolin being derived from a kaolin having a high pore volume. Kaolin having a high pore volume can be a pulverized ultrafine kaolin or a kaolin which has been pulverized to have an incipient slurry point less than 57% solids.
摘要:
This invention discloses a catalyst and process for removing nitrogen oxides from exhaust streams under lean burn conditions using hydrocarbons as the reductant. Catalysts consists of two phases, a metal exchanged molecular sieve and a stabilizing metal oxide associated with the molecular sieve.