The present invention relates to the use of haloapatites as catalysts of the dehydration reaction of -hydroxylated carboxylic acids or acid esters, in particular of lactic acid or of methyl lactate, and also to a process for producing unsaturated carboxylic acids or acid esters, in particular acrylic acid or methyl acrylate, in the gas phase in a stainless steel reactor, in the presence of such a catalyst.

Hydrotreating catalysts are provided having one or more phosphorus components carried on a composite support of a titanium-loaded binder component and post-framework modified ultra-stable Y-type zeolite. The support comprises the titanium-loaded binder component and a post-framework modified ultra-stable Y-type (USY) zeolite in which a portion of aluminum atoms constituting a zeolite framework thereof is substituted with zirconium atoms and/or titanium atoms and/or hafnium atoms. The active components including the phosphorous active component and one or more hydrocracking metals active components loaded on the support.

Hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof are dehydrated using a catalyst and a method to produce bio-acrylic acid, acrylic acid derivatives, or mixtures thereof. A method to produce the dehydration catalyst is also provided.

Hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof are dehydrated using a catalyst and a method to produce bio-acrylic acid, acrylic acid derivatives, or mixtures thereof. A method to produce the dehydration catalyst is also provided.

Catalysts for dehydrating hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof to acrylic acid, acrylic acid derivatives, or mixtures thereof with high yield and selectivity, short residence time, and without significant conversion to undesired side products, such as, for example, acetaldehyde, propionic acid, and acetic acid, are provided. The catalysts are mixed protonated monophosphates. Methods of preparing the catalysts are also provided.

Hydrotreating catalysts are provided having one or more phosphorus components carried on a composite support of a titanium-loaded binder component and post-framework modified ultra-stable Y-type zeolite. The support comprises the titanium-loaded binder component and a post-framework modified ultra-stable Y-type (USY) zeolite in which a portion of aluminum atoms constituting a zeolite framework thereof is substituted with zirconium atoms and/or titanium atoms and/or hafnium atoms. The active components including the phosphorous active component and one or more hydrocracking metals active components loaded on the support.

A method of producing an ethylenically unsaturated carboxylic acid or ester, preferably an , ethylenically unsaturated carboxylic acid or ester. The method includes contacting formaldehyde or a suitable source thereof with a carboxylic acid or ester in the presence of a catalyst and optionally in the presence of an alcohol. The catalyst includes a nitrided metal oxide having at least two types of metal cations, M.sup.1 and M.sup.2, wherein M.sup.1 is selected from the metals of group 2, 3, 4, 13 (called also IIIA) or 14 (called also IVA) of the periodic table and M2 is selected from the metals of groups 5 or 15 (called also VA) of the periodic table.

Processes for the catalytic dehydration of hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof to acrylic acid, acrylic acid derivatives, or mixtures thereof with high yield and selectivity and without significant conversion to undesired side products, such as, acetaldehyde, propanoic acid, and acetic acid, are provided. The processes can be carried out either in a gas phase or in a liquid phase.

Catalysts for dehydrating hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof to acrylic acid, acrylic acid derivatives, or mixtures thereof with high yield and selectivity, short residence time, and without significant conversion to undesired side products, such as, for example, acetaldehyde, propionic acid, and acetic acid, are provided. The catalysts are mixed protonated monophosphates. Methods of preparing the catalysts are also provided.

Hydroxypropionic acid, hydroxypropionic acid derivatives, or mixtures thereof are dehydrated using a catalyst and a method to produce bio-acrylic acid, acrylic acid derivatives, or mixtures thereof. A method to produce the dehydration catalyst is also provided.