Abstract: Low temperature hydrothermal treatment of an LTL zeolite-producing mixture produces a colloidal suspension of the zeolite; the suspension may be used as seeds in Al-- and Ga--LTL zeolite manufacture.

Abstract: The invention relates to zeolites which have high substitution levels of element with regard to aluminium content and in particular such zeolites where the substitute to silicon ratio is also high. A method for producing such zeolites by presenting the substitute material in tetrahedral oxo-anion form is also provided.

Abstract: Binderless particles of zeolite L of very high mechanical strength are prepared by a process which comprises forming a mixture by reacting substantially binderless particles of zeolite L, preferably as shaped particles such as extrudates, with an aqueous alkaline solution containing sources of alkali metal, at least 50 mole % of which is potassium, and aluminium to obtain the desired particles of very high mechanical strength. The zeolite L thus obtained can form part of a dehydrocyclisation and/or isomerisation catalyst.

Abstract: A method is disclosed for preparing crystalline aluminosilicate zeolite L from a reaction mixture containing only sufficient water to produce zeolite L. In one embodiment, the reaction mixture is self-supporting and may be shaped if desired. In the method, the reaction mixture is heated at crystallization conditions and in the absence of an added external liquid phase, so that excess liquid need not be removed from the crystallized product prior to drying the crystals.

Abstract: Zeolite L containing caesium having enhanced catalytic properties is prepared by a process in which said zeolite L is crystallized from a synthesis mixture with a molar composition (expressed as oxides) of:______________________________________ K.sub.2 O/SiO.sub.2 0.22 to 0.30 K.sub.2 O/Cs.sub.2 O 5 to 12 H.sub.2 O/K.sub.2 O 50 to 90 and SiO.sub.2 /Al.sub.2 O.sub.3 6.0 to 7.0 ______________________________________and containing 0.5 to 20 ppm (by weight) of divalent metal cations, e.g. Mg ions. The zeolite L can form part of a dehydrocyclization and/or isomerisation catalyst.

Abstract: ECR-31 is a new zeolite having a 12-ring channel. It may be expected to have similar properties to other 12-ring channel zeolites in catalysis and separations.

Abstract: Binderless zeolite L particles are prepared by a method in which particles are formed from silica and from 0 to 95 wt % preformed zeolite L crystallites, and the particles are thereafter reacted with an alkaline solution comprising a source of alumina to convert the silica binder to zeolite L. These particles may comprise cylindrical zeolite L crystallites with a mean diameter of at least 0.05 micron in a zeolite L matrix and may be used as catalyst. Also acyclic hydrocarbons are dehydrocyclized and/or isomerized by contacting them at a temperature of from 370.degree. C. to 600.degree. C. with this catalyst incorporating at least one Group VIII metal having dehydrogenating activity to convert at least part of the acyclic hydrocarbons into aromatic hydrocarbons.

Abstract: Molecular sieve compositions are prepared by extracting aluminum and substituting chromium and/or tin for extracted aluminum to give molecular sieve products containing framework chromium and/or tin atoms. The process of preparing the chromium and/or tin-containing molecular sieves involves contacting a starting molecular sieve with a solution or slurry of at least one of a fluoro salt of chromium or a fluoro salt of tin under effective process conditions to provide for aluminum extraction and substitution of chromium and/or tin.

Abstract: Binderless zeolite L particles are prepared by a method in which particles are formed from silica and from 0 to 95 wt % preformed zeolite L crystallites, and the particles are thereafter reacted with an alkaline solution comprising a source of alumina to convert the silica binder to zeolite L. These particles may comprise cylindrical zeolite L crystallites with a mean diameter of at least 0.05 micron in a zeolite L matrix and may be used as catalyst. Also acyclic hydrocarbons are dehydrocyclized and/or isomerized by contacting them at a temperature of from 370.degree. C. to 600.degree. C. with this catalyst incorporating at least one Group VIII metal having dehydrogenating activity to convert at least part of the acyclic hydrocarbons into aromatic hydrocarbons.

Abstract: The crystal size and shape of zeolite KL can be improved by forming the zeolite from a synthesis mixture in which the molar ratio of K.sub.2 O/SiO.sub.2 is 0.18 to 0.36, and in which the synthesis mixture comprises iron preferably in an amount such that the molar ratio of Fe.sub.2 O.sub.3 /Al.sub.2 O.sub.3 is 0.015 to 0.3.

Abstract: Molecular sieve compositions are prepared by extracting aluminum and substituting chromium and/or tin for extracted aluminum to give molecular sieve products containing framework chromium and/or tin atoms. The process of preparing the chromium and/or tin-containing molecular sieves involves contacting a starting molecular sieve with a solution or slurry of at least one of a fluoro salt of chromium or a fluoro salt of tin under effective process conditions to provide for aluminum extraction and substitution of chromium and/or tin.

Abstract: The reaction of premade gels with KOH in aqueous ammonia solvents yields highly crystalline but ultrasmall particulate, colloidal, products having major advantages in catalytic and sorption process.

Abstract: Zeolite L with flat basal planes, and reduced crystallite size is prepared in a synthesis modified by the addition of small amounts of additional metal such as magnesium, calcium, barium, cobalt, zinc, chromium, manganese or nickel. The addition of these metals also suppresses unwanted zeolite W formation even when the synthesis would otherwise form this zeolite.