Abstract: The present invention comprises a hydrocarbon-conversion process using an improved MgAPSO-31 molecular sieve which demonstrates a favorable combination of conversion and selectivity in aromatics conversion. The sieve has a specific combination of crystal configuration, being limited in diameter and length, specified crystallinity as measured by an X-Ray Diffraction Index (XRDI), and a narrow range of magnesium content.

Abstract: The present invention comprises a hydrocarbon-conversion process using an improved MgAPSO-31 molecular sieve which demonstrates a favorable combination of conversion and selectivity in aromatics conversion. The sieve has a specific combination of crystal configuration, being limited in diameter and length, specified crystallinity as measured by an X-Ray Diffraction Index (XRDI), and a narrow range of magnesium content.

Abstract: A process for preparing crystalline alumino-silicate compositions has been developed. The process involves preparing a charge density mismatch reaction mixture comprising sources of aluminum, silicon, optionally an E metal and at least one charge density mismatch (CDM) template. The CDM template is an organic nitrogen containing template, in the hydroxide form, e.g. tetraethylammonium hydroxide and is characterized in that it is incapable of inducing crystallization. To this mixture there is added a solution comprising a second templating agent termed a crystallization template (CT). The CT can be an organic template different from the CDM template, an alkali metal, an alkaline earth metal and mixtures thereof.

Abstract: A method is provided for converting a hydrocarbon feedstock in the naphtha boiling range to light olefins. The method includes contacting the hydrocarbon feedstock with a zeolitic material having a crystal size from 50 to 300 nanometers, having a silica to alumina ratio greater than 200 and where the zeolitic material has a silicalite structure.

Abstract: Applicants have synthesized a new crystalline aluminosilicate zeolite identified as UZM-4M. This new zeolite is obtained by treating a UZM-4 zeolite with a fluorosilicate salt to obtain a zeolite having the empirical formula: M1an+Al1-xExSiyOz where M1 is an alkali metal, alkaline earth metal, rare earth metal, hydronium ion or ammonium ion, E can be gallium, iron, boron, indium and mixtures thereof and has a Si/Al ratio of 1.5 to about 10.

Abstract: Applicants have synthesized a new crystalline aluminosilicate zeolite identified as UZM-4M.

Abstract: Applicants have synthesized a new aluminosilicate zeolite identified as UZM-4. This new zeolite has the BPH morphology and is structurally related to zeolite Q. UZM-4 has en empirical formula of Mmn+Rrp+Al1−xExSiyOz where M is an alkali or alkaline earth metal ion, R can be a quaternary ammonium ion and E can be gallium, iron, boron, chromium, indium and mixtures thereof. The Si/Al ratio can range from 1.5 to about 4.

Abstract: Applicants have prepared a novel zeolite identified as LZ-281. This zeolite has the framework topology of zeolite EMT. The LZ-281 zeolite is prepared by removing framework aluminum atoms from EMC-2 zeolite while simultaneously replacing the aluminum atoms with extraneous silicon atoms. This increases the SiO2/Al2O3 ratio versus the starting EMC-2 zeolite and results in the LZ-281 zeolite having increased thermal stability, increased number and/or strength of acid sites and increased activity in hydrocarbon processes requiring strong acid sites.

Abstract: Applicants have prepared a novel zeolite identified as LZ-281. This zeolite has the framework topology of zeolite EMT. The LZ-281 zeolite is prepared by removing framework aluminum atoms from EMC-2 zeolite while simultaneously replacing the aluminum atoms with extraneous silicon atoms. This increases the SiO.sub.2 /Al.sub.2 O.sub.3 ratio versus the starting EMC-2 zeolite and results in the LZ-281 zeolite having increased thermal stability, increased number and/or strength of acid sites and increased activity in hydrocarbon processes requiring strong acid sites.

Abstract: Molecular sieve compositions have been synthesized which are resistant to the loss of framework atoms. Specifically, the molecular sieves of the invention have the empirical formulamA: (M.sub.w Al.sub.x Si.sub.y)O.sub.2where A is at least one rare earth metal, M is chromium or titanium and "m", "w", "x" and "y" are the mole fractions of A, M, Al and Si respectively. Applicants have discovered that the rare earth metals prevent loss of chromium and titanium from the framework and degradation of the molecular sieve. Along with the composition, a process for preparing the composition and processes using the composition are disclosed and claimed.