摘要:
Mixed ketones are prepared from a mixture of carboxylic acids in a process with high selectivity by using an improved catalyst. The catalyst contains zirconium dioxide or zirconium dioxide and titanium dioxide, and a Group 1 or 2 metal silicate or phosphate salt. The new catalyst is more selective toward the formation of the mixed ketone, as opposed to a symmetrical ketone.
摘要:
Mixed ketones are prepared from a mixture of carboxylic acids in a process with high selectivity by using an improved catalyst. The catalyst contains zirconium dioxide or zirconium dioxide and titanium dioxide, and a Group 1 or 2 metal silicate or phosphate salt. The new catalyst is more selective toward the formation of the mixed ketone, as opposed to a symmetrical ketone.
摘要:
Mixed ketones are prepared from a mixture of carboxylic acids in a process with high selectivity by using an improved catalyst. The catalyst contains zirconium dioxide or zirconium dioxide and titanium dioxide, and a Group 1 or 2 metal silicate or phosphate salt. The new catalyst is more selective toward the formation of the mixed ketone, as opposed to a symmetrical ketone.
摘要:
A process for removing metal species from a composition comprising contacting: a. an oligomer mixture stream comprising the monomers of a partially aromatic polyester polymer and at least one metal species, or b. a molten polyester polymer stream comprising partially aromatic polyester polymers and at least one metal species, with a non-catalytic porous material in the presence of hydrogen to produce a treated stream containing a reduced amount of at least one metal species. There are provided compositions comprising a partially aromatic polyester polymer having an It.V. of at least 0.50 produced in a direct esterification melt phase process, from greater than 0 to less than 50 ppm antimony, and less than 40 ppm cobalt, or produced in an ester exchange melt phase process, having from greater than zero to less than 5 ppm titanium and less than 10 ppm manganese.
摘要:
Disclosed is a process for the preparation of dimethyl cyclohexanedicarboxylates by the hydrogenation of the corresponding dimethyl benzenedicarboxylate ester in the presence of supported catalysts comprising (i) a Group VIII metal and (ii) a catalyst support material selected from graphite and silicon carbide.
摘要:
A catalyst for the preparation of ketones from carboxylic acids is described. The catalyst comprises a mixture of zirconium dioxide, titanium dioxide, and one or more metal oxides from Group 1 or 2 of the Periodic Table of Elements. The catalyst can operate at a lower temperature, reduce coke formation, and provide longer lifetime.
摘要:
Disclosed are catalysts comprising copper chromite, palladium and lanthanum having hydrogenation activity. The combination of copper chromite with palladium and lanthanum enhances catalyst activity more than the presence of either palladium alone or palladium in combination with alkali or alkaline earth metals. The catalysts are useful for the preparation of methanol from carbon monoxide and hydrogen and for the hydrogenation of carbonyl compounds such as, for example, aldehydes, ketones, and esters, to their corresponding alcohols. The catalysts may be used for the preparation of cyclohexanedimethanols from dialkyl cyclohexanedicarboxylates or of ethylene glycol from alkyl glycolates.
摘要:
The present disclosure relates to the production of a 2,2,4,4-tetraalkylcyclobutane-1,3-diol. In one embodiment, the present invention relates to the production of a 2,2,4,4-tetraalkylcyclobutane-1,3-diol by hydrogenation of a 2,2,4,4-tetraalkylcyclobutane-1,3-dione in the presence of an iridium-promoted cobalt-based catalyst.
摘要:
The present disclosure relates to the production of a 2,2,4,4-tetraalkylcyclobutane-1,3-diol. In one embodiment, the present invention relates to the production of a 2,2,4,4-tetraalkylcyclobutane-1,3-diol by hydrogenation of a 2,2,4,4-tetraalkylcyclobutane-1,3-dione in the presence of an iridium-promoted cobalt-based catalyst.
摘要:
A process comprising contacting a liquid polyester stream with hydrogen in the presence of a hydrogenation catalyst comprising a metal supported on the surface of silicon carbide at a metal dispersion of at least 0.5% or graphite at a metal dispersion of at least 10% to produce a treated liquid polyester stream. The treated stream may be polycondensed in the presence of a polycondensation catalyst to produce a polyester polymer having an It.V. of at least 0.55 dL/g. The liquid polyester stream desirably has a composition comprising: a) terephthalic acid residues, isophthalic acid residues, and/or naphthalenedicarboxylic acid residues and b) an average degree of polymerization of 0.5 to 20 and c) an acid number ranging from 5 to 600.