Abstract: A catalyst in the form of extruded bodies is disclosed, which consists of an inert binding agent and a catalytically active phase of a silica/alumina gel. The catalyst is particularly active in acid-catalysed reactions.

Abstract: The present invention relates to a mesoporous gel comprising an alumina matrix in which one or more oxides selected from silica, boron oxide, phosphorus oxide, oxides of metals of groups VIII and VIB, may be uniformly dispersed. The present invention also relates to a process for the preparation of this gel and its uses as carrier, as catalyst for acid-catalyzed reactions and as hydrotreating catalyst.

Abstract: A process is described for the production of D-&agr;-amino acids by the stereospecific conversion of racemic mixtures of 5-substituted hydantoins using a microorganism transformed with a plasmid which expresses an enzymatic system which converts the hydantoins into the corresponding D-&agr;-amino acids without the requirement for inducers. Also described is a plasmid containing genes encoding the enzymatic system, and a microorganism transformed with the plasmid.

Abstract: The present invention provides a nickel cermet, which includes: 35% to 70% by weight of a nickel phase, and 65% to 30% by weight of zirconium oxide phase, wherein the zirconium oxide is stabilized in cubic form by 5 to 20 moles of yttrium oxide for each 100 moles of said zirconium oxide, and the metal nickel and zirconium oxide phases, upon X ray diffraction analysis are distinct and homogeneously distributed; and is prepared by a process that includes: a) dispersing zirconia stabilized by yttria having a particle size of between 1 and 40 &mgr;m , in demineralized water to prepare a suspension; b) dissolving a hydrosoluble and thermodecomposable nickel salt in demineralized d water to prepare a solution; c) mixing the nickel solution with the suspension and homogenizing the resulting dispersion by magnetic stirring for a time of between 5 and 40 minutes; d) eliminating the water from the dispersion by a system capable of operating without, or almost without, decomposition phenomena to obtain a solid th

Abstract: The invention relates to a new asporogenous strain of Bacillus subtilis which has been deposited at the Centraalbureau Voor Schimmelcultures under the number CBS 432.90. This strain, which shows a frequency of reversion to the formation of spores of less than about 10−8 and good plasmid stability, is suitable as a host in a host-vector system for the preparation of heterologous products of interest.

Abstract: Process for preparing porous spherical silica particles substantially consisting in emulsifying an acidic silica sol in a dispersing media, gelifying the microdrops of the sol in the emulsified state and submitting the resulting gel to thermal treatment in the presence of the emulsifier liquid and of sol gelation base.

Abstract: A synthetic, crystalline, porous material is disclosed, together with the related preparation process. Such material of zeolitic nature containing oxides of silicon, titanium and gallium corresponds, in the calcined and anhydrous state, to the following empyrical formula:pHGaO.sub.2 .multidot.qTiO.sub.2 .multidot.SiO.sub.2,wherein p has a value greater than zero and smaller than or equal to 0.050, and q has a value greater than zero and smaller than or equal to 0.025, and the H.sup.+ of HGaO.sub.2 can be at least partially replaceable or replaced by cations.

Abstract: The present invention relates to a process for the catalytic reduction of nitrogen oxides contained in exhaust gases from combustion, which process comprises bringing said exhaust gases into contact with a Beta Zeolite exchanged with suitable amounts of cobalt salts, in the presence of a light hydrocarbon as the reducing agent. The present invention relates also to a catalyst for such a process, which catalyst comprises a Beta Zeolite exchanged with cobalt salts, characterized by a Co:zeolite Al molar ratio of <0.5.

Abstract: The present invention relates to a process for the preparation of a micro-meso porous material which comprises:a) preparing a mixture starting from a tetraalkylorthosilicate, a C.sub.3 -C.sub.6 alkyl alcohol or dialcohol, a tetraalkylammonium hydroxide having the formula R.sub.1 (R.sub.2).sub.3 N--OH wherein R.sub.1 is a C.sub.3 -C.sub.7 alkyl and R.sub.2 is a C.sub.1 or C.sub.3 -C.sub.7 alkyl, optionally in the presence of one or more metal compounds, in which the molar ratios are within the following ranges:alcohol/SiO.sub.2 <or equal to 20;R.sub.1 (R.sub.2).sub.3 N--OH/SiO.sub.2 =0.05-0.4;H.sub.2 O/SiO.sub.2 =1-40;metal oxides/SiO.sub.2 =0-0.02;b) subjecting this mixture to hydrolysis and subsequent gelation at a temperature of between 20.degree. C. and a temperature close to the boiling point of the alcohol or mixture of alcohols present;c) subjecting the gel obtained to drying and calcination.

Abstract: A superacid catalyst comprising zirconium oxide having a purely tetragonal crystalline phase structure and whose surface has sulfate groups thereon in a quantity corresponding to the total coverage of the surface of the zirconium oxide by a monolayer of said sulfate groups, the zirconium oxide having a porosimetric distribution consisting of at least 70% of pores having a diameter ranging from 1-4 nm.

Abstract: Solid mesoporous crystalline composition of a pyrophosphate-phosphate of a tetravalent metal, with a high surface area and narrow distribution of the mesopores, having formula (I):M(P.sub.2 O.sub.7).sub.1-z (HPO.sub.4).sub.2z (I)wherein: M is a tetravalent metal and z varies from 0.05 to 0.25.The process for its production is described together with its uses.

Abstract: The present invention provides a NOx reducing catalyst comprising BEA zeolite which is ion-exchanged with Co to have a Co/Al ratio between 0.2 and 0.6 and is loaded with at least one metal selected from among Ca, Sr, Ba, La, Mn, Ag, In, and Ni. The present invention also provides a NOx reduction process comprising the use of the catalyst of the present invention. The catalyst of this invention provides high activity, high NOx reduction selectivity and durability at low temperature in an actual exhaust gas containing water vapor and other substances disturbing catalytic activity even at low temperature and at low NOx and hydrocarbon concentration.

Abstract: The present invention relates to a catalyst for reduction of nitrogen oxides in exhaust gas containing oxygen by hydrocarbons, which comprises cobalt-loaded zeolite not showing a Raman spectral band assignable to cobalt oxide (Co.sub.3 O.sub.4).

Abstract: Process for the hydroisomerization of n-paraffins in the presence of a difunctional catalyst which comprises:(a) a porous crystalline material isostructural with beta-zeolite selected from boro-silicate (BOR-B) and boro-alumino-silicate (AL-BOR-B) in which the molar SiO.sub.2 :Al.sub.2 O.sub.3 ratio is higher than 300:1;(b) one or more metal(s) belonging to Group VIIIA, selected from platinum and palladium, in an amount comprised within the range of from 0.05 to 5% by weight.

Abstract: Disclosed is an active catalyst in the hydroisomerization of waxes (paraffins), which catalyst is constituted by a carrier of acidic nature, of silica-alumina gel, and one or more metals belonging to Group VIIIA. Also a process for preparing said catalyst is disclosed.

Abstract: Process for the consolidation of sand in a well which produces fluids, particularly oil and/or gas, comprising the following steps:1) optional preflush with an aqueous solution of inorganic salts, preferably KCl;2) injection into the formation of a consolidating agent essentially consisting of an aqueous solution of sodium silicate in water;3) flushing with an inert gas, preferably nitrogen, of the formation treated in step (2) until the excess consolidating agent and water injected in step (2) have been removed;4) subsequent introduction into the formation thus treated of an aqueous solution of an acid having a pKa at 25.degree. C. of between 3 and 10, preferably selected from ammonium chloride and acetic acid.

Abstract: A porous, crystalline material, designated ERS-10 zeolite, having in its calcined and anhydrous form a molecular composition of oxides corresponding to the formula (I):mM.sub.2/n O.zX.sub.2 O.sub.3.YO.sub.2 (1)wherein m, n, M, z, X and Y are as defined herein, the crystalline material having an X-ray diffraction spectrum shown in Table 1 herein.

Abstract: Process for the hydroisomerization of n-paraffins in the presence of a difunctional catalyst which comprises:(a) a porous crystalline material isostructural with beta-zeolite selected from boro-silicate (BOR-B) and boro-alumino-silicate (Al-BOR-B) in which the molar SiO.sub.2 :Al.sub.2 O.sub.3 ratio is higher than 300:1;(b) one or more metal(s) belonging to Group VIIIA, selected from platinum and palladium, in an amount comprised within the range of from 0.05 to 5% by weight.

Abstract: Solid mesoporous crystalline composition of diphospho-nate-phosphite of a tetravalent metal, with a limited distribution of mesopores having the formulaM?(O.sub.3 P--R--PO.sub.3).sub.1-x-y (HPO.sub.3).sub.2x (O.sub.3 P--R--PO.sub.3 H.sub.2).sub.2y !wherein: M is a tetravalent metal, R is a bivalent organic radical, x varies from 0.3 to 0.6, y varies from 0.05 to 0.3. The process for its production is described, together with its uses and a solid catalyst containing --SO.sub.3 H acid groups, active in the conversion processes of hydrocarbons, which can be obtained from said mesoporous crystalline composition by treatment with a sulfonicphosphonic or arylphosphonic acid, followed, only in the case of treatment with arylphosphonic acid, by sulfonation with a sulfonating agent.

Abstract: A synthetic, crystalline, porous material is disclosed, together with the related preparation process. Such material of zeolitic nature containing oxides of silicon, titanium and gallium corresponds, in the calcined and anhydrous state, to the following empyrical formula:pHGaO.sub.2.qTiO.sub.2.SiO.sub.2,wherein p has a value greater than zero and smaller than or equal to 0.050, and q has a value greater than zero and smaller than or equal to 0.025, and the H.sup.+ of HGaO.sub.2 can be at least partially replaceable or replaced by cations.