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.

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.

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.

Processes for the purification of bio-based acrylic acid to crude and glacial acrylic acid are provided. The bio-based acrylic acid is produced from hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof. The purification includes some or all of the following processes: extraction, drying, distillation, and melt crystallization. The produced glacial or crude acrylic acid contains hydroxypropionic, hydroxypropionic acid derivatives, or mixtures thereof as an impurity.

Processes for the purification of bio-based acrylic acid to crude and glacial acrylic acid are provided. The bio-based acrylic acid is produced from hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof. The purification includes some or all of the following processes: extraction, drying, distillation, and melt crystallization. The produced glacial or crude acrylic acid contains hydroxypropionic, hydroxypropionic acid derivatives, or mixtures thereof as an impurity.

The invention relates to the conversion of paraffinic hydrocarbon to oligomers of greater molecular weight and/or to aromatic hydrocarbon. The invention also relates to equipment and materials useful in such conversion, and to the use of such conversion for, e.g., natural gas upgrading. Corresponding olefinic hydrocarbon is produced from the paraffinic hydrocarbon in the presence of a dehydrogenation catalyst containing a catalytically active carbonaceous component. The corresponding olefinic hydrocarbon is then converted by oligomerization and/or dehydrocyclization in the presence of at least one molecular sieve catalyst.

The invention relates to the conversion of paraffinic hydrocarbon to oligomers of greater molecular weight and/or to aromatic hydrocarbon. The invention also relates to equipment and materials useful in such conversion, and to the use of such conversion for, e.g., natural gas upgrading. Corresponding olefinic hydrocarbon is produced from the paraffinic hydrocarbon in the presence of a dehydrogenation catalyst containing a catalytically active carbonaceous component. The corresponding olefinic hydrocarbon is then converted by oligomerization and/or dehydrocyclization in the presence of at least one molecular sieve catalyst.

Catalysts, catalytic forms and formulations, and catalytic methods are provided. The catalysts and catalytic forms and formulations are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane. Related methods for use and manufacture of the same are also disclosed.

Catalysts, catalytic forms and formulations, and catalytic methods are provided. The catalysts and catalytic forms and formulations are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane. Related methods for use and manufacture of the same are also disclosed.

A two or particularly three-phase process, and corresponding apparatus, desulfurizes sour hydrocarbon gas, e.g., natural gas, generally better than known, using a fixed-bed, two-phase processes in terms of the amount of H.sub.2S scavenged and the breakthrough time of H.sub.2S. The three-phase process is effective in scavenging H.sub.2S at ambient temperature and pressure, using a copper salt catalyst impregnated on alumina or other generally inert support, which is regenerable.