| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 562887000 | Carboxylic acid anhydrides (i.e., compounds having the -C(=O)-O-C(=O)- group) | 10 |
| 20090234161 | METHOD FOR THE PRODUCTION OF (METH)ACRYLIC ANHYDRIDE - The present invention relates to an improved method for manufacturing (meth)acrylic anhydride by transanhydrization between (meth)acrylic acid and acetic anhydride, in the presence of air and in the presence of at least one polymerization inhibitor, characterized in that the polymerization inhibitor is chosen from the group formed from (a) metal salts of thiocarbamic or dithiocarbamic acid and their mixtures with a phenolic derivative or phenothiazine and its derivatives, and (b) N-oxyl compounds as a mixture with 2,6-di-tert-butyl-4-methylphenol taken alone or in the presence of 2,4-dimethyl-6-tert-butylphenol. | 09-17-2009 |
| 20140005435 | METHOD FOR PRODUCING (METH)ACRYLIC ANHYDRIDE, METHOD FOR STORING (METH)ACRYLIC ANHYDRIDE, AND METHOD FOR PRODUCING (METH)ACRYLATE | 01-02-2014 |
| 562888000 | Processes of forming the -C(=O)-O-C(=O)- group | 8 |
| 20100069666 | IMPROVED METHOD FOR THE PRODUCTION OF UNSATURATED CARBOXYLIC ACID ANHYDRIDES - The invention provides an improved process for preparing unsaturated carboxylic anhydrides of the general formula I | 03-18-2010 |
| 562890000 | Carbon monoxide or metal carbonyl reactant | 3 |
| 20130197267 | Processes for Preparing Acetic Anhydride - In one embodiment, the invention is to a process for producing acetic anhydride. The process includes at least a step of carbonylating methanol and/or a methanol derivative with carbon monoxide to form acetic acid, and contacting ketene with the acetic acid to form a crude acetic anhydride product stream and a vent stream having unreacted ketene. The process further comprises a step of directing at least a portion of the vent stream to a liquid ring vacuum compressor having a ring seal fluid comprising acetic acid The unreacted ketene in the portion of the vent stream contacts the ring seal fluid to form supplemental acetic anhydride. | 08-01-2013 |
| 562891000 | Ether or carboxylic acid ester reactant | 2 |
| 20090177007 | PROCESS FOR PRODUCING CARBOXYLIC ACID ANHYDRIDES - The present invention relates to a process for producing carboxylic acid anhydrides, in which a carboxylic acid ester, derived from an alcohol and a carboxylic acid, and carbon monoxide containing a small amount of hydrogen are used as raw materials and subjected to a carbonylation reaction in a liquid reaction medium in the presence of a Group VIII B catalyst to produce a carboxylic acid anhydride. The reaction medium comprises the Group VIII B catalyst, an organic halide, the carboxylic acid ester, an alkali metal salt, at least one organic promoter, the carboxylic acid anhydride and the carboxylic acid, wherein the organic promoter is selected from at least one of the following structural forms (I), (II) and (III). According to the process of the present invention, the reaction rate of the carbonylation reaction is increased by the use of the specified organic promoters. | 07-09-2009 |
| 20100145098 | PROCESS FOR PRODUCING CARBOXYLIC ACID ANHYDRIDES - A process for producing carboxylic acid anhydrides by the carbonylation reaction of a carboxylic acid ester, derived from an alcohol and a carboxylic acid, with carbon monoxide containing a small amount of hydrogen in a liquid reaction medium in the presence of a Group VIII B catalyst to produce a carboxylic acid anhydride. The reaction medium comprises the Group VIII B catalyst, an organic halide, the carboxylic acid ester, an alkali metal salt, the carboxylic acid anhydride, the carboxylic acid, and at least one ionic liquid consisting of a cation and an anion where the cation of the ionic liquid has a nitrogen-containing heterocyclic structure. The ionic liquid has at least one of the following structural forms: | 06-10-2010 |
| 562892000 | Ketone or ketene reactant | 2 |
| 20130072718 | HIGH SHEAR SYSTEM AND PROCESS FOR THE PRODUCTION OF ACETIC ANHYDRIDE - A method for producing acetic anhydride that includes operating a high shear device at a shear rate of greater than about 20,000 s | 03-21-2013 |
| 20140066653 | Processes For Purifying Acetic Anhydride and Method of Making Same - In one embodiment, the invention is to a process for purifying acetic anhydride. The process includes the steps of feeding a liquid crude acetic anhydride stream directly to a distillation column and separating the liquid crude acetic anhydride stream to produce a light ends stream, a sidedraw and a residue stream. The sidedraw comprises substantially pure acetic anhydride product. The distillation column is operated at a pressure less than 101 kPa. The substantially pure acetic anhydride product comprises greater than 98 wt. % acetic anhydride, has a permanganate time of greater than 10 minutes, and has an APHA color of less than 10. | 03-06-2014 |
| 562893000 | Ether or carboxylic acid ester reactant | 1 |
| 20100317892 | METHOD FOR PREPARING (METH)ACRYLIC ANHYDRIDE - The present invention relates to an improved method for preparing (meth)acrylic anhydride (A(M)A | 12-16-2010 |
| 562895000 | Dehydration of two like or different molecules of carboxylic acid | 1 |
| 20160122273 | PROCESS FOR THE PREPARATION OF HALOGENATED CARBOXYLIC ANHYDRIDES - The present invention relates to a process for the preparation of halogenated carboxylic anhydrides, e.g. for the preparation of trifluoroacetic anhydride. The preparation is achieved by reacting a halogenated carboxylic acid, e.g. trifluoroacetic acid, with sulfuric acid, oleum and/or disulfuric acid. | 05-05-2016 |
