Provided are the following: an MWW type zeolite which has many Brnsted acid sites when in the form of a proton type and which is highly suitable as a cracking catalyst for cumene; a method for producing same; and an application of same. The present invention provides an MWW type zeolite in which the ratio (B/A) of the peak intensity (B) attributable to tetracoordinate aluminum relative to the peak intensity (A) attributable to hexacoordinate aluminum is 2 or more in .sup.27Al MAS NMR, when measured as an ammonium type. The present invention also provides a method for producing an MWW type zeolite, the method having a step for carrying out a hydrothermal synthesis reaction in the presence of: a seed crystal of an MWW type zeolite containing no organic structure-directing agent; and a reaction mixture containing a silica source, an alumina source, an alkali source, an organic structure-directing agent, and water. The reaction mixture satisfies the following molar ratio: X/SiO.sub.2<0.15 (here, X denotes the number of moles of the organic structure-directing agent).

The present disclosure relates to a process for producing a mono-alkylated aromatic compound, such as, for example, ethylbenzene or cumene, in which an alkylatable aromatic compound stream, such as, for example, benzene, and an alkylation agent stream, such as, for example, poly-ethylbenzene or poly-isopropylbenzene, are contacted in the presence of a transalkylation catalyst and under at least partial liquid phase transalkylation conditions. The transalkylation catalyst comprises a zeolite having a framework structure selected from the group consisting of FAU, BEA*, MOR, MWW and mixtures thereof. The zeolite has a silica-alumina molar ratio in a range of 10 to 15. The transalkylation catalyst composition has an external surface area/volume ratio in the range of 30 cm.sup.1 to 85 cm.sup.1.

Catalyst compositions comprising a zeolite and a mesoporous support or binder are disclosed. The mesoporous support or binder comprises a mesoporous metal oxide having a particle diameter of greater than or equal to 20 m at 50% of the cumulative pore size distribution (d50). Also disclosed are processes for producing a mono-alkylated aromatic compound (e.g., ethylbenzene or cumene) which exhibit improved yield of the mono-alkylated aromatic compound using alkylation catalysts comprising one or more of these catalyst compositions.

Methods for removing impurities from a hydrocarbon stream using a guard bed material are disclosed. The guard bed material includes compositions which comprises a zeolite and a mesoporous support or binder. The zeolite has a Constraint Index of less than 3. The mesoporous support or binder comprises a mesoporous metal oxide having a particle diameter of greater than or equal to 20 m at 50% of the cumulative pore size distribution (d.sub.50), a pore volume of less than 1 cc/g, and an alumina content of greater than 75%, by weight. Also disclosed are processes for producing mono-alkylated aromatic compounds (e.g., ethylbenzene or cumene) using impure feed streams that are treated by the disclosed methods to remove impurities which act as catalyst poisons to downstream alkylation and/or transalkylation catalysts.

The invention relates to a process for dehydration of a mono-alcohol, or of a mixture of at least two mono-alcohols, having at least 2 carbon atoms and at most 7 carbon atoms into olefins having the same number of carbons, wherein the process uses a catalyst composition that comprises a modified crystalline aluminosilicate has an acidity between 350 and 500 mol/g that comprises, and further wherein the catalyst composition is obtained by a process comprising the steps of providing a crystalline aluminosilicate having a Si/Al framework molar ratio greater than 10; and steaming said crystalline aluminosilicate, or said shaped and/or calcined crystalline aluminosilicate at a temperature ranging from 100 C. to 380 C.; and under a gas phase atmosphere, without liquid, containing from 5 wt % to 100 wt % of steam; at a pressure ranging from 2 to 200 bars; at a partial pressure of H.sub.2O from 2 bars to 200 bars; and said steaming being performed during at least 30 min and up to 144 h.

Processes are described for isomerizing one or more C.sub.14-C.sub.24 alpha olefins to produce an isomerization mixture comprising one or more C.sub.14-C.sub.24 internal olefins comprising contacting an olefinic feed comprising the one or more C.sub.14-C.sub.24 alpha olefins with a catalyst under isomerization conditions, wherein the catalyst comprises a microporous crystalline aluminosilicate having an MWW framework. The resulting isomerization mixture typically exhibits a low pour point with maintained biodegradability properties as compared to the olefinic feed, and is particularly useful in drilling fluid and paper sizing compositions.

The present disclosure relates to a process for producing a mono-alkylated aromatic compound using a treated catalyst made by a method of this invention is disclosed. The method comprises the steps of heating an untreated catalyst in the presence of a gaseous stream having a dew point temperature less than about 5 C. to form a treated catalyst. The treatment is effective to improve the activity and selectivity of the catalyst.

Described herein is a process for producing a zeolitic material having an MWW framework structure containing YO.sub.2 and B.sub.2O.sub.3, in which Y stands for a tetravalent element. The process includes the steps of (i) preparing a mixture containing one or more sources for YO.sub.2, one or more sources for B.sub.2O.sub.3, one or more organotemplates, and seed crystals, (ii) crystallizing the mixture obtained in (i) for obtaining a layered precursor of the MWW framework structure, and (iii) calcining the layered precursor obtained in (ii) for obtaining the zeolitic material having an MWW framework structure. Also disclosed herein are synthetic boron-containing zeolites obtain by the process and uses thereof.

Process for the preparation of a catalyst and a catalyst comprising enhanced mesoporosity is provided herein. Thus, in one embodiment, provided is a particulate FCC catalyst comprising 2 to 50 wt % of one or more ultra stabilized high Si02/A1203 ratio large pore faujasite zeolite or a rare earth containing USY, 0 to 50 wt % of one or more rare-earth exchanged large pore faujasite zeolite, 0 to 30 wt % of small to medium pore size zeolites, 5 to 45 wt % quasi-crystalline boehmite 0 to 35 wt % microcrystalline boehmite, 0 to 25 wt % of a first silica, 2 to 30 wt % of a second silica, 0.1 to 10 wt % one or more rare earth components showiomg enhanced mesoporosity in the range of 6-40 nm, the numbering of the silica corresponding to their orders of introduction in the preparation process.

The disclosure relates to a process for continuously producing polyoxymethylene dimethyl ethers at low temperature, pertains to the technical field of polyoxymethylene dimethyl ether preparation processes, and solves the technical problem of continuous production of polyoxymethylene dimethyl ether. A membrane separation element with precisely controlled pores in membrane is used to realize a direct separation of the feedstocks from the catalyst within the reactor, and effectively reduce the permeation resistance of the separation membrane tube. By oppositely switching the flowing direction of liquid reaction materials, the adhesion of the catalyst to the separation membrane tube is inhibited, and some particles stuck in separation membrane tube are removed, which ensures the continuous operation of the reaction process and allows a molecular sieve catalyst to exhibit its advantage of long catalytic life.