Abstract: A plasma source comprises a thermionic emitter (2) heated by an induction coil (7), which also provides radiofrequency energy within an electrically insulated cylindrical former (1). A cylindrical anode (10) is concentric with emitter (2) and axially displaced therefrom, generating a potential difference between anode (10) and emitter (2). The potential difference between anode (2) and ground and axial magnetic fields causes the plasma to be extracted from the source. Emitter (2) is held at negative potential via a conductive support (5). Process gas is introduced near emitter (2) and a secondary gas injected in the anode space. Radiofrequency excitation of emitter (2) generates electrons via thermionic and field effects, resulting in efficient plasma generation. Both electron generation effects contribute to a broad energy spectrum of electrons, providing effective neutralization of the plasma.

Abstract: A retaining component comprises first and second end walls and a third wall between the first and second end walls. The first and second end walls each have a first edge adjacent to the third wall and a second edge remote from the third wall. The first and second end walls extend to one side of the plane of the third wall. The retaining component has at least one lug projecting from the second edge of each of the first and second end walls. Each lug has a transverse hole whereby the retaining component can be connected to a like or similar component by passing an elongate member through aligned holes in lugs of the two components.

Abstract: Apparatus (10) for treating a substrate, comprising: a vacuum chamber (12); a substrate carrier (14) adapted to carry a substrate (16) to be treated; a source material holder (22) for holding a source material (34) with which the substrate (16) is to be treated; and vaporising or sputtering means (20) for vaporising/sputtering the source material (34); wherein the source material holder (22) includes a positioning means (24) for relatively moving the source material (34) towards the substrate carrier (14).

Abstract: A process useful in steam cracking is disclosed for selectively converting a feed comprising C4+ dienes and oxygenate to a product comprising increased C2+ monoolefins and para-xylene levels by contacting said feed under diolefin conversion conditions with a catalyst comprising a porous crystalline material having a Diffusion Parameter for 2,2-dimethylbutane of about 0.1-100 sec−1 when measured at a temperature of 120° C. and a 2,2-dimethylbutane pressure of 60 torr (8 kPa), a temperature of 430° C. and 0.5 WHSV.

Abstract: This invention relates to a new synthetic porous crystalline material, designated MCM-67, a method for its preparation and use thereof in catalytic conversion of organic compounds. MCM-67 appears to be closely related in structure to VPI-8 and SSZ-41 but is synthesized without zinc and in the presence of manganese and/or cobalt ions.

Abstract: Incorporation of zirconium, nickel and/or copper into M41S results in selective sorption of bulky organic molecules. Zirconium, nickel and/or copper may be incorporated into M41S by exchange or impregnation.

Abstract: This invention provides a method of producing an aromatics alkylation catalyst comprising the steps of:(a) synthesizing a layered oxide material MCM-56 in the presence of alkali and/or alkaline earth metal cations;(b) prior to any calcination of the MCM-56, subjecting the MCM-56 produced in step (a) to ammonium ion exchange so as to at least partially replace the alkaline or alkaline earth metal cations associated with the MCM-56 with ammonium ions; then(c) heating the ammonium-exchanged MCM-56 to decompose the ammonium cations and convert the MCM-56 into the hydrogen form; and(d) after step (b), forming the MCM-56 into catalyst particles.The resultant catalyst exhibits enhanced activity in the alkylation of benzene with ethylene and propylene.

Abstract: This invention relates to a new synthetic porous crystalline material, designated MCM-68, a method and novel polycyclic organic cation for its preparation and its use in catalytic conversion of organic compounds. The new crystalline material exhibits a distinctive X-ray diffraction pattern and has a unique crystal structure which contains at least one channel system, in which each channel is defined by a 12-membered ring of tetrahedrally coordinated atoms, and at least two further, independent channel systems, in each of which each channel is defined by a 10-membered ring of tetrahedrally coordinated atoms, wherein the number of unique 10-membered ring channels is twice the number of 12-membered ring channels.

Abstract: There is provided a catalyst and a process for converting methanol or dimethyl ether to a product containing C.sub.2 to C.sub.4 olefins. The catalyst comprises a porous crystalline material having a Diffusion Parameter for 2,2-dimethylbutane of about 0.1-20 sec.sup.-1 when measured at a temperature of 120.degree. C. and a 2,2-dimethylbutane pressure of 60 torr (8 kPa). In addition, the catalyst is characterized by a hydrothermal stability such that, after steaming the catalyst at 1025.degree. C. for 45 minutes in 1 atmosphere steam, the catalyst exhibits a methanol conversion activity of at least 50% when contacted with methanol at a methanol partial pressure of 1 atmosphere, a temperature of 430.degree. C. and 0.5 WHSV. The porous crystalline material is preferably a medium-pore zeolite, particularly ZSM-5, which contains phosphorus and has been severely steamed at a temperature of at least 950.degree. C.

Abstract: There is provided a process for converting methanol and/or dimethyl ether to a product containing C.sub.2 to C.sub.4 olefins which comprises the step of contacting a feed which contains methanol and/or dimethyl ether with a catalyst comprising a porous crystalline material, said contacting step being conducted in the presence of an aromatic compound under conversion conditions including a temperature of 350.degree. C. to 480.degree. C. and a methanol partial pressure in excess of 10 psia (70 kPa), said porous crystalline material having a pore size greater than the critical diameter of the aromatic compound and the aromatic compound being capable of alkylation by the methanol and/or dimethyl ether under said conversion conditions.

Abstract: There is described a process and a catalyst for the hydroalkylation of an aromatic hydrocarbon, particularly benzene, wherein the catalyst comprises a first metal having hydrogenation activity and a crystalline inorganic oxide material having a X-ray diffraction pattern including the following d-spacing maxima 12.4.+-.0.25, 6.9.+-.0.15, 3.57.+-.0.07 and 3.42.+-.0.07.

Abstract: A process is described for isomerizing a feed which contains ethylbenzene and xylene, which process comprises the steps of:(a) contacting the feed under ethylbenzene conversion conditions with a particulate first catalyst component which comprises a molecular sieve having a constraint index of 1-12, the particles of said first catalyst component having a surface to volume ratio of about 80 to less than 200 inch.sup.-1 and the contacting step converting ethylbenzene in the feed to form an ethylbenzene-depleted product; and then(b) contacting the ethylbenzene-depleted product under xylene isomerization conditions with a second catalyst component.

Abstract: In a synthetic porous crystalline material having the structure of ZSM-5 and a composition involving the molar relationship: X.sub.2 O.sub.3 :(n)YO.sub.2, wherein X is a trivalent element; Y is a tetravalent element; and n is greater than about 12, the crystals have a major dimension of at least about 0.5 micron and surface framework YO.sub.2 /X.sub.2 O.sub.3 ratio which is no more than 20% less than the bulk framework YO.sub.2 /X.sub.2 O.sub.3 ratio of the crystal. The material is synthesized using an amino-acid as a directing agent.

Abstract: A method for minimizing the loss of xylenes in an ethylbenzene conversion/isomerization process by adding toluene to the feedstock. The concentration of toluene in the feedstock is increased by co-feeding toluene or by recycling toluene separated from the ethylbenzene conversion reactor effluent. The increased toluene concentration reduces the loss of xylenes during the ethylbenzene conversion reaction and under preferred operating conditions increases the amount of xylenes in the product.

Abstract: A process is provided for producing pyridine and/or alkylpyridine compounds comprising reacting a feedstream of ammonia and at least one C.sub.1-5 carbonyl reactant under conversion conditions and in the presence of a phosphorus-modified molecular sieve containing catalyst to produce a product stream having a pyridine and/or a pyridine based compound selected from alkylpyridines or polyalkylpyridines. The catalyst has improved attrition resistance without affecting catalyst activity or selectivity.

Abstract: There is provided a catalyst comprising ZSM-5, rhenium which is impregnated onto the catalyst, and a selectivating agent. The selectivating agent may be coke and/or a siliceous material. The catalyst is particularly useful for catalyzing toluene disproportionation reactions. Methods for making this catalyst and processes for using this catalyst in toluene disproportionation are also provided.

Abstract: There is provided a process for shape selective xylene disproportionation that involves contacting a feedstream which includes xylene under conversion conditions, with a molecular sieve catalyst that has been surface modified. The xylene disproportionation process has a selectivity for pseudocumene of over 85%.

Abstract: A method for increasing the efficiency of xylene isomerization by using a two stage isomerization process. In the first stage of the process, a C.sub.9.sup.+ aromatics feedstock is subjected to ethylbenzene conversion and xylene isomerization. Non-C.sub.8 aromatics are removed from the effluent, which is then processed in a second stage of the process to remove para-xylene and isomerize the para-xylene depleted effluent. The effluent from the second stage isomerization unit is then recycled into the inlet of the second stage of the process and a slip stream from the para-xylene separator is recycled to the feedstock and to the effluent of the ethylbenzene conversion unit. In this way, the production of para-xylene is maximized. In a preferred embodiment, toluene is co-fed into the feedstock to minimize the loss of xylenes during the ethylbenzene conversion reaction.

Abstract: There is provided a high efficiency base synthesis process for shape selective production of pyridine and picoline products from ammonia and C.sub.1-5 carbonyl compounds. The process includes reacting ammonia and at least one C.sub.1-5 carbonyl reactant under suitable reaction conditions of temperature, pressure, and space velocity in the presence of a catalyst comprising a molecular sieve to produce a primary product comprising pyridine or picoline products and polyalkylpyridines or other higher molecular weight aromatic species, separating and collecting the pyridine or picoline products from the polyalkylpyridines or other higher molecular weight aromatic species, and circulating the polyalkylpyridines or other higher molecular weight aromatic species to the same or another catalyst under conversion conditions to yield additional pyridine or picoline products with substantially reduced amounts of polyalkylpyridines or other higher molecular weight aromatic species.

Abstract: A composition for passivating metal contaminants in catalytic cracking of hydrocarbons includes a non-layered, ultra-large pore crystalline material with at least one peak at a position greater than about 18 Angstrom Units d-spacing with a relative intensity of 100, and a benzene adsorption capacity of greater than about 15 grams benzene per 100 grams anhydrous crystal at 50 torr and 25.degree. C., and a metal passivator incorporated within the crystalline material. A method for passivating contaminating metals uses the composition during catalytic cracking as an additive or as a component of the catalyst.