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Recently, a new operational scheme for a zeolite crystallizer was reported which facilitated the experimental investigation of high silica ZSM-5 crystal growth and could be used for nucleation studies. The unique feature of the operation was that seed crystals were placed in an appropriate solution in a gently stirred tank vessel, and fresh clear reagent solution was pumped into the vessel on a continuous...
A nonequilibrium distribution of methylamines is prepared by the catalyzed reaction of methanol and/or dimethyl ether with ammonia followed by the catalytic reforming of the methylamine-containing feedstock produced. The process selectively affords a reaction product enriched in mono- and dimethylamines and low in trimethylamine, at high conversion of methanol or dimethyl ether. The low trimethylamine...
Granules of a laundry detergent composition containing surfactants, zeolite builders, enzymes, and bleaching agents are coated with a powdered secondary (2,3)-alkyl sulfate [e.g., NaC 16 secondary (2,3)alkyl sulfate] to improve the flowability of the granules.
The β-zeolites are manufactured by adding an organic templating agent (tetraethylammonium hydroxide or tetraethylammonium halides), NaOH or H 2 SO 4 , and an Al source into water glass (mol ratio SiO 2 Na 2 O = 2.0-3.7). The β-zeolites have a composition expressed in terms of oxide mol ratios: SiO 2 Al 2 O 3 = 10-infinity, (tetra-Et NH 4...
The average degree of branching of a branched olefin feedstock is reduced by skeletal isomerization in contact with a molecular sieve catalyst having a 10-membered ring pore structure, for example zeolite H-ZSM-22.
ETS-10 is a large pore titanosilicate molecular sieve with unique properties due to its peculiar pore structure and charge distributions. Extensive use of multinuclear n.m.r. in the present work has enabled elucidation of the effect of cations on the local structure and electronic environment in ETS-10. MAS 23 Na n.m.r. shows that Na + ions in NaETS-10 reside in both the 12-...
A process is described for preparing alkyl tertiary-alkyl ethers, especially methyl tertiary-butyl ether, in one step which comprises reacting tertiary-butanol and a C 1 -C 4 primary alcohol in the presence of a catalyst consisting essentially of a pentasil zeolite having a silica/alumina ratio of 50-150, optionally with a binder, at a temperature of 80-200°C and at atmospheric pressure...
Aromatic amines are prepared in high yield by treatment of phenols with NH 3 , primary amines, or secondary amines in the presence of solid acids containing F, especially zeolite H-USY, previously treated with NH 4 F and calcined.
A modified large pore zeolitic molecular sieve structure is disclosed for adsorbing alkenes emitted during internal combustion engine startup, before the catalytic converter has attained its effective operating temperature. The zeolitic molecular sieve is modified by inserting certain metal ions into its structure. In particular, a modified Y zeolite having a high adsorption capacity for propylene...
A process is described for producing dialkyl carbonates which comprises contacting an alkanol, carbon monoxide, and oxygen with a catalyst, the catalyst having been prepared by heating a solid copper compound in the presence of a zeolite (e.g., Y zeolite with a SiO 2 Al 2 O 3 molar ratio of 12:1) to form a zeolite-containing copper.
Adsorbents for carbon dioxide are sodium-containing aluminosilicates having 2-80 equivalent % of Na ion exchanged with Ba ion. The adsorbents are manufactured by immersion of sodium-containing aluminosilicates in aqueous Ba salt solution. The adsorbents are especially useful for CO 2 separation by a pressure-swing adsorption method.
A method for the conversion of light hydrocarbon raw materials containing mainly C 2-12 paraffins to lower olefins (containing major components of ethylene and propylene) and single ring aromatic hydrocarbons comprises contacting the light hydrocarbons with an intermediate pore aluminosilicate zeolite catalyst containing 0.1-10 wt% of one of transition metals selected from...
A process for the production of dialkyl carbonates such as dimethyl carbonate is described. The process involves contacting under reaction conditions an alkanol such as methanol with carbon monoxide and oxygen in the vapor phase and in the presence of a catalyst containing a copper halide, a copper oxyhalide, or a copper carboxylate halide, and a quaternary ammonium salt, on a zeolite support component...
The title process consists of treating crystalline aluminosilicate zeolites with Al removing agents in an aqueous phase at pH 4 in the presence of PO 3-4 and water-soluble silica. Optionally, the agents, PO 3-4 , and the silica are gradually added into the aqueous phase containing 0.01-0.3 mol of SiO 2 /mol of zeolite.
Zeolite NaA and sodium dinonylnaphthalenesulfonate (NaDNNS) have been used to decontaminate and recycle Zn, V, Cd, and Hg ions from textile fabric waste waters. A comparative study of the kinetics, temperature, ionic strength, and pH effects of the uptake of the above mentioned cations by the two exchangers is made. It is concluded that NaDNNS has certain advantages over zeolite NaA.
A particulate foam control agent for addition to powdered laundry detergents comprises a zeolite carrier, a siloxane (antifoaming agent), a polyoxyalkylenesiloxane that enhances the release of the siloxane upon contact with water, and a polycarboxylate binder or encapsulant.
Catalytically active phosphorus-containing zeolites, particularly ultrastable zeolite Y, are prepared by reacting an exchanged zeolite with a phosphorus compound such as H 3 PO 4 , steaming, and reacting the steamed product with additional phosphorus compound.
A cellulase is used with inorganic builders, especially zeolite NaA, in detergent compositions to inhibit graying of washed fabrics caused by soil redeposition during laundering.
This is a process for the hydroisomerization of n-paraffins in the presence of a difunctional catalyst which comprises a porous crystalline material isostructural with zeolite β selected from borosilicates or boroaluminosilicates in which the SiO 2 Al 2 O 3 molar ratio is higher than 300:1; and one or more metal(s) belonging to group VIIIA, selected from platinum and palladium...
A combined catalytic cracking and olefin production process uses a coked catalytic cracking catalyst as a dehydrogenation catalyst to dehydrogenate an alkane feed and form an olefin-rich product. Preferably the coked catalytic cracking catalyst has a carbon content of 0.2-10%. The method uses a staged back mixed regeneration system to form the dehydrogenation catalyst and to reactivate fully the...
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