Layered double hydroxides having a high surface area (at least 125 m.sup.2/g) and the formula (I)
[M.sup.z+.sub.1?xM.sup.y+.sub.x(OH).sub.2].sup.a+(X.sup.n?).sub.a/n.sub.+bH.sub.2O.c(AMO-solvent)(I)
wherein M and M are different and each is a charged metal cation (and must be present), z=1 or 2; y=3 or 4, 0<x<0.9, b is 0 to 10, c=0 to 10, X is an anion, n is the charge on the anion, and a=z(1?x)+xy?2; AMO-solvent is aqueous miscible organic solvent, may be prepared by a method which comprises a) precipitating a layered double hydroxide having the formula
[M.sup.z+.sub.1?xM.sup.y+.sub.x(OH).sub.2].sup.a+(X.sup.n?).sub.a/n.sub.+bH.sub.2O wherein M, M, z, y, x, a, b and X are as defined above from a solution containing the cations of the metals M and M and the anion X.sup.n?; b) ageing the layered double hydroxide precipitate obtained in step a) in the original solution; c) collecting, then washing the layered double hydroxide precipitate; d) dispersing the wet layered double hydroxide in an AMO solvent so as to produce a slurry of the layered double hydroxide in the solvent; e) maintaining the dispersion obtained in step d); and f) recovering and drying the layered double hydroxide. The high surface area products have low particle size and are particularly suitable for use as catalysts, catalyst supports, sorbents and coatings.

Provided is a method for producing carbon nanotibers having excellent conductivity, crystallinity and dispersibility. A method for producing carbon nanofibers, which uses an activated species mainly composed of cobalt as a catalyst, while using carbon monoxide as a carbon source. The catalyst is obtained by having a carrier, which is composed of an oxide having a specific surface area of 0.01-5 m.sup.2/g and containing magnesium, support 3-90% by mass of the activated species. By controlling the reaction temperature, the carbon monoxide partial pressure and the gas flow rate of the carbon monoxide, CNF having more excellent conductivity, crystallinity and dispersibility can be produced, thereby obtaining carbon nanofibers having excellent conductivity, crystallinity and dispersibility.

The composite of the present invention includes zeolite having a metal hydroxide supported thereon, and thus it can release moisture inside the zeolite effectively. Therefore, the warm-mix asphalt additive including the composite is not only economical but also able to lower with ease the temperatures required for mixing and compacting an asphalt mixture. Also, the asphalt mixture including the above-described warm-mix additive has a benefit of an improved adhesive strength, which leads to an excellent resistance to plastic deformation.

The composite of the present invention includes zeolite having a metal hydroxide supported thereon, and thus it can release moisture inside the zeolite effectively. Therefore, the warm-mix asphalt additive including the composite is not only economical but also able to lower with ease the temperatures required for mixing and compacting an asphalt mixture. Also, the asphalt mixture including the above-described warm-mix additive has a benefit of an improved adhesive strength, which leads to an excellent resistance to plastic deformation.

Processes and multiple-stage catalyst systems are disclosed for producing propene by at least partially isomerizing butene in an isomerization reaction zone having an isomerization catalyst to form an isomerization reaction product, at least partially metathesizing the isomerization reaction product in a metathesis reaction zone having a metathesis catalyst to form a metathesis reaction product, and at least partially cracking the metathesis reaction product in a cracking reaction zone having a cracking catalyst. The isomerization catalyst may be MgO, and the metathesis catalyst may be a mesoporous silica catalyst support impregnated with a metal oxide. The metathesis reaction zone may be downstream of the isomerization reaction zone, and the cracking reaction zone may be downstream of the metathesis reaction zone.

Processes and multiple-stage catalyst systems are disclosed for producing propene by at least partially isomerizing butene in an isomerization reaction zone having an isomerization catalyst to form an isomerization reaction product, at least partially metathesizing the isomerization reaction product in a metathesis reaction zone having a metathesis catalyst to form a metathesis reaction product, and at least partially cracking the metathesis reaction product in a cracking reaction zone having a cracking catalyst. The isomerization catalyst may be MgO, and the metathesis catalyst may be a mesoporous silica catalyst support impregnated with a metal oxide. The metathesis reaction zone may be downstream of the isomerization reaction zone, and the cracking reaction zone may be downstream of the metathesis reaction zone.

The present invention relates to a method of preparing a catalyst for oxidative dehydrogenation. More particularly, the present invention provides a method of preparing a catalyst for oxidative dehydrogenation providing superior selectivity and yield for a conjugated diene according to oxidative dehydrogenation by constantly maintaining pH of a coprecipitation solution using a drip-type double precipitation method to adjust an ?-iron oxide content in a catalyst in a predetermined range.

A catalyst comprising gold, palladium, and a porous support, in the form of at least one grain, in which: the gold content in the catalyst is in the range 0.5% to 3% by weight with respect to the total weight of catalyst; the mean particle size of the gold, estimated by transmission electron microscopy (TEM), is in the range 0.5 nm to 5 nm; the gold is distributed homogeneously in the porous support; at least 80% by weight of the palladium is distributed in an eggshell at the periphery of the porous support; the gold/palladium molar ratio is more than 2.

The present disclosure relates to chemical catalysts and methods that may be used for the production and/or interconversion of olefins. In some embodiments, methods for producing propylene from ethylene and butene comprising, (a) obtaining a catalyst composition comprising an isomerization catalyst and a disproportionation catalyst, wherein the weight ratio of the isomerization catalyst to the disproportionation catalyst is from 10:1 to 1:10; and (b) reacting butene with ethylene at a temperature from about 500? F. (260? C.) to about 650? F. (350? C.) in the presence of the catalyst composition under conditions sufficient to produce propylene are provided.

The present disclosure relates to chemical catalysts and methods that may be used for the production and/or interconversion of olefins. In some embodiments, methods for producing propylene from ethylene and butene comprising, (a) obtaining a catalyst composition comprising an isomerization catalyst and a disproportionation catalyst, wherein the weight ratio of the isomerization catalyst to the disproportionation catalyst is from 10:1 to 1:10; and (b) reacting butene with ethylene at a temperature from about 500? F. (260? C.) to about 650? F. (350? C.) in the presence of the catalyst composition under conditions sufficient to produce propylene are provided.