Systems and methods are provided for catalytically dewaxing a diesel boiling range feed. In some aspects, catalytic dewaxing can be performed at low hydrogen treat gas rates and/or low hydrogen purity conditions. In other aspects, the systems and methods can allow for distillate dewaxing while reducing or minimizing the amount of equipment required.

Catalyst systems are provided, along with corresponding methods, for single stage conversion of synthesis gas to fuel boiling range products with increased selectivity for either naphtha production (C.sub.5-C.sub.9) or distillate production (C.sub.10-C.sub.20). The increased selectivity for naphtha production or distillate production is provided in conjunction with a reduced selectivity for higher boiling range components (C.sub.21+).

Methods are provided for using a molecular sieve catalyst for dewaxing formed using a synthesis mixture comprising a morphology modifier. The catalyst may be used, for example, for production of a lubricant base stock. For example, ZSM-48 crystals formed using the morphology modifier (and/or formulated catalysts made using such crystals) can have an increased activity and/or can provide an improved yield during catalytic dewaxing of lubricant base stocks.

A molecular sieve has a silica/alumina molar ratio of 100-300, and has a mesopore structure. One closed hysteresis loop appears in the range of P/P.sub.0=0.4-0.99 in the low temperature nitrogen gas adsorption-desorption curve, and the starting location of the closed hysteresis loop is in the range of P/P.sub.0=0.4-0.7. The catalyst formed from the molecular sieve as a solid acid not only has a good capacity of isomerization to reduce the freezing point, but also can produce a high yield of the product with a lower pour point. The process for preparing the catalyst involves steps including crystallization, filtration, calcination, and hydrothermal treatment.

Catalysts including at least one microporous material (e.g., zeolite), an organosilica material binder, and at least one catalyst metal are provided herein. Methods of making the catalysts, preferably without surfactants and processes of using the catalysts, e.g., for aromatic hydrogenation, are also provided herein.

A family of new crystalline molecular sieves designated SSZ-91 is disclosed, as are methods for making SSZ-91 and uses for SSZ-91. Molecular sieve SSZ-91 is structurally similar to sieves falling within the ZSM-48 family of molecular sieves, and is characterized as: (1) having a low degree of faulting, (2) a low aspect ratio that inhibits hydrocracking as compared to conventional ZSM-48 materials having an aspect ratio of greater than 8, and (3) is substantially phase pure.

The invention relates to a process for combined ethylbenzene reforming and xylene isomerisation comprising contacting a hydrocarbon feedstock containing ethylbenzene and xylene with a catalyst comprising a catalyst carrier and one or more metal(s) supported on the catalyst carrier, wherein the catalyst carrier is an extrudate comprising (i) a ZSM-48 and/or EU-2 type zeolite and (ii) an alumina binder, the extrudate having a shape with a C/A value of at least 3, where C is the circumference of the extrudate and A is the cross-sectional area of the extrudate. The metal may be platinum and the alumina may be a wide-pore alumina. The process displays high conversion rates whilst maintaining low levels of side-product formation.

Disclosed are a catalyst system and its use in a process for the conversion of a feedstock containing C.sub.8+ aromatic hydrocarbons to produce light aromatic products, comprising benzene, toluene and xylene. The catalyst system comprises (a) a first catalyst bed comprising a first catalyst composition, said first catalyst composition comprising a zeolite having a constraint index of 3 to 12 combined (i) optionally with at least one first metal of Group 10 of the IUPAC Periodic Table, and (ii) optionally with at least one second metal of Group 11 to 15 of the IUPAC Periodic Table; and (b) a second catalyst bed comprising a second catalyst composition, said second catalyst composition comprising (i) a meso-mordenite zeolite, combined (ii) optionally with at least one first metal of Group 10 of the IUPAC Periodic Table, and (iii) optionally with at least one second metal of Group 11 to 15 of the IUPAC Periodic Table, wherein said meso-mordenite zeolite is synthesized from TEA or MTEA and having a mesopore surface area of greater than 30 m.sup.2/g and said meso-mordenite zeolite comprises agglomerates composed of primary crystallites, wherein said primary crystallites have an average primary crystal size as measured by TEM of less than 80 nm and an aspect ratio of less than 2.

A process for reducing haze in a heavy base oil includes: obtaining a first effluent oil by contacting a hydrocarbon feedstock with a first catalyst including a zeolite of the ZSM-12 family; and obtaining a second effluent oil by contacting the first effluent oil with a second catalyst including a zeolite of the ZSM-48 family. A hydroisomerization catalyst system having reduced haze includes: a first catalytic region having a first catalyst disposed therein, the first catalyst including a zeolite of the ZSM-12 family; and a second catalytic region having a second catalyst disposed therein, the second catalyst including a zeolite of the ZSM-48 family. The first catalytic region is disposed upstream of the second catalytic region.

The invention relates to a process for combined ethylbenzene reforming and xylene isomerisation comprising contacting a hydrocarbon feedstock containing ethylbenzene and xylene with a catalyst comprising a catalyst carrier and one or more metal(s) supported on the catalyst carrier, wherein the catalyst carrier is an extrudate comprising (i) a ZSM-48 and/or EU-2 type zeolite and (ii) an alumina binder, the extrudate having a shape with a C/A value of at least 3, where C is the circumference of the extrudate and A is the cross-sectional area of the extrudate. The metal may be platinum and the alumina may be a wide-pore alumina. The process displays high conversion rates whilst maintaining low levels of side-product formation.