| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 562600000 | Purification or recovery per se | 42 |
| 20080281124 | Method For Purifying (Meth)Acrylic Acid Obtained By Oxidizing a Gaseous Substrate - The present invention relates to a method for purifying (meth)acrylic acid obtained by catalytic or redox oxidation of a gaseous substrate constituting propane, propylene, acrolein, isobutane, isobutene, tert-butyl alcohol and/or (meth)acrolein or mixtures thereof by sending the gaseous reaction mixture to the bottom of a countercurrent absorption column (C | 11-13-2008 |
| 20080281125 | Process for Preparing Enantiopure E-(2S)-Alkyl-5-Halopent-4-Enoic Acids and Esters - A process for preparing enantiopure E-(2S)-alkyl-5-halopent-4-enoic acids and their esters of the formula (I), | 11-13-2008 |
| 20090192332 | Method for Preparing Isoprenyl Cysteine Compounds and Analogs Thereof - Methods of preparing isoprenyl cysteine compounds by coupling a cysteine compound with an activated (i.e. halogenated) lipid are disclosed. Also disclosed, among other things, are methods of making activated (i.e. halogenated) lipids, and methods of purifying isoprenyl cysteine compounds. | 07-30-2009 |
| 20090203938 | USE OF PHOSPHORIC ESTERS AS DEPOSIT CONTROL AGENTS DURING THE SYNTHESIS, PURIFICATION OR REGENERATION OF (METH)ACRYLIC MONOMERS - The compounds of formula (I) are provided as deposition inhibitors which prevent the deposition of compounds of polymeric nature or resulting from addition reactions to (meth)acrylic double bonds during operations for the synthesis or purification or regeneration of (meth)acrylic monomers. | 08-13-2009 |
| 20090253934 | Process for Producing Acrylic Acid - The process for the distillation of a gas mixture comprising (meth)acrylic acid obtained from the gas-phase oxidation of at least one (meth)acrylic acid precursors is improved through the use of coupled distillation columns. In a first column, the gaseous mixture is dehydrated while in a second column, the dehydrated gaseous mixture is distilled into product, overhead and bottoms streams. | 10-08-2009 |
| 20090270652 | PROCESS FOR TRANSFERRING HEAT TO A LIQUID COMPRISING DISSOLVED MONOMERIC ACRYLIC ACID, MICHAEL ACRYLIC ACID OLIGOMERS AND ACRYLIC ACID POLYMER - A process for transferring heat to a liquid F comprising dissolved monomeric acrylic acid, Michael acrylic acid oligomers, and acrylic acid polymer with the aid of an indirect heat exchanger to which are supplied the liquid F with a temperature T | 10-29-2009 |
| 20090299095 | Method for production of aqueous (meth)acrylic acid - The present invention relates to recovery of aqueous (meth)acrylic acid by condensation of a (meth)acrylic acid-containing stream to produce aqueous (meth)acylic acid having a higher concentration of (meth)acrylic acid and a lower concentration of formaldehyde, i.e., not more than 0.1 weight %, than the aqueous (meth)acrylic acid produced using hithertofore known separation methods. The (meth)acrylic acid-containing stream may be the raw product stream of catalytic oxidation at least one C | 12-03-2009 |
| 20100228053 | METHOD FOR EXTRACTING METHACRYLIC ACID - Disclosed is a method for extracting methacrylic acid, in which an extraction solvent is added to a methacrylic acid aqueous solution for transferring methacrylic acid to the extraction solvent. In this method, a solvent containing t-butyl methacrylate is used as the extraction solvent. | 09-09-2010 |
| 20110172462 | CONTROL OF A PROCESS FOR THE PURIFICATION OF (METH)ACRYLIC ACID USING ON-LINE, NEAR IR ANALYSIS - An improved process for the manufacture of technical grade (meth)acrylic acid, e.g., acrylic acid, the process comprising producing a hydrated reaction product from the gas-phase oxidation of at least one (meth)acrylic acid precursor, e.g., propylene, followed by first dehydrating and then concentrating the reaction product, the improvement comprising controlling at least one of the water, acetic acid and (meth)acrylic acid content of the reaction product during the purification of the reaction product using on-line, near IR spectroscopy. | 07-14-2011 |
| 20110201842 | METHOD FOR RECOVERING CARBOXYLIC ACIDS FROM DILUTE AQUEOUS STREAMS - Improvement in separating lower carboxylic acids from aqueous streams via liquid-liquid extraction with pressurized liquefied propylene and/or propane, wherein carboxylic acid is transferred from the aqueous phase into the liquid solvent phase (extract). | 08-18-2011 |
| 20110319661 | PROCESS FOR PRODUCING (METH) ACRYLIC ACID - A process for producing (meth)acrylic acid of the present invention comprises the steps in the following order: a crystallization step of supplying a cooling medium cooled by a heat source device to a crystallizer to obtain a (meth)acrylic acid crystal from a crude (meth)acrylic acid solution; an adjustment step of returning the cooling medium discharged from the crystallizer to the crystallizer without cooling; a sweating step of supplying a heating medium to the crystallizer to partially melt the (meth)acrylic acid crystal, thereby obtaining a melted liquid, and discharging the melted liquid from the crystallizer; and a melting step of supplying the heating medium to the crystallizer to melt the (meth)acrylic acid crystal, thereby obtaining purified (meth)acrylic acid. According to the present invention, purified (meth)acrylic acid with high purity can be obtained. | 12-29-2011 |
| 20120046495 | PROCESS FOR PRODUCTION OF (METH) ACRYLIC ACID - The objective of the present invention is to provide a process for producing highly pure (meth) acrylic acid stably and efficiently with crystallization. The process for production of (meth)acrylic acid according to the present invention is characterized in comprising the steps of cooling a crude (meth)acrylic acid solution in a crystallization apparatus until the temperature of a cooling medium discharged from the crystallization apparatus is stabilized in the range of higher than the solidification point of the crude (meth)acrylic acid solution in the crystallization apparatus and not more than the solidification point plus 5° C.; then bringing the crude (meth)acrylic acid solution in the crystallization apparatus to a supercooled condition by setting the temperature of a cooling medium supplied to the crystallization apparatus at the temperature of not more than the solidification point of the crude (meth)acrylic acid solution minus 1° C.; and crystallizing (meth)acrylic acid from the crude (meth)acrylic acid solution. | 02-23-2012 |
| 20120083624 | PROCESS FOR PRODUCTION OF (METH)ACRYLIC ACID - The objective of the present invention is to provide a process for production of (meth)acrylic acid with improved production efficiency by efficiently shifting from heating procedure to cooling procedure for a crystallizer. A process for production of (meth)acrylic acid according to the present invention is characterized in comprising the steps of crystallizing (meth)acrylic acid from a crude (meth)acrylic acid solution by using a batch type crystallizer, and melting the obtained (meth)acrylic acid crystal to obtain a (meth)acrylic acid melted liquid; wherein preliminary cooling of the crystallizer for the next crystallization step is started during transferring the (meth)acrylic acid melted liquid from the crystallizer. | 04-05-2012 |
| 20120088932 | PROCESS FOR PRODUCING (METH) ACRYLIC ACID - A process for producing (meth)acrylic acid, comprising the step of repeating a crystallization operation “n” times (providing “n” is an integer 2 or more) to produce purified (meth)acrylic acid from crude (meth)acrylic acid, wherein a (meth)acrylic acid solution is crystallized and the crystallized (meth)acrylic acid is melted to obtain a (meth)acrylic acid melt in the crystallization operation; wherein a constant amount A | 04-12-2012 |
| 20120108847 | DEVICE AND PROCESS FOR CRYSTALLIZING (METH) ACRYLIC ACID - The objective of the present invention is to provide a crystallization device and a crystallization process for obtaining (meth)acrylic acid with higher purity without causing leakage of a crude solution by preventing complete clogging in a crystallization tube from occurring. The device for crystallizing (meth)acrylic acid according to the present invention is characterized in comprising a crude (meth)acrylic acid solution supply part, a crystallization tube, a heat medium supply tube, a heat medium discharge tube, a storage part of a crude (meth)acrylic acid solution passed through the crystallization tube, a tube for circulating and supplying the crude (meth)acrylic acid solution to the supply part from the storage part, and a pump for circulating and supplying the crude (meth)acrylic acid solution to the supply part from the storage part; and further comprising a pressure meter in the circulate-supply tube; wherein the device is used for carrying out dynamic crystallization in a batch manner by circulating the crude (meth)acrylic acid solution to flow the crude solution downward along the inner wall of the crystallization tube in a coating film-like state. | 05-03-2012 |
| 20120226074 | PROCESS FOR PRODUCING ACRYLIC ACID - The process for the distillation of a gas mixture comprising (meth)acrylic acid obtained from the gas-phase oxidation of at least one (meth)acrylic acid precursors is improved through the use of coupled distillation columns. In a first column, the gaseous mixture is dehydrated while in a second column, the dehydrated gaseous mixture is distilled into product, overhead and bottoms streams. | 09-06-2012 |
| 20130085301 | Processes for Producing Acrylic Acids and Acrylates - In one embodiment, the invention is to a process for producing an acrylate product. The process comprises the step of providing a crude product stream comprising the acrylate product, an alkylenating agent, and water. The process further comprises the step of contacting at least a portion of the crude product stream or a derivative thereof with an extraction agent mixture to form an extract stream and a raffinate stream. The extract stream comprises acrylate product and extraction agent. The raffinate stream comprises alkylenating agent and water. Preferably, the extraction agent mixture comprises at least two extraction agents. | 04-04-2013 |
| 20130085302 | Processes for Producing Acrylic Acids and Acrylates - In one embodiment, the invention is to a process for producing an acrylate product. The process comprises the step of providing a crude product stream comprising the acrylate product and an alkylenating agent. The process further comprises the step of separating at least a portion of the crude product stream to form an alkylenating agent stream and an intermediate product stream. The process further comprises the step of recovering high purity acrylate product using precipitation. The alkylenating agent stream comprises at least 1 wt % alkylenating agent and the intermediate product stream comprises acrylate product. | 04-04-2013 |
| 20130085303 | Processes for Producing Acrylic Acids and Acrylates - In one embodiment, the invention is to a process for producing an acrylate product. The process comprises the step of providing a crude product stream comprising the acrylate product, an alkylenating agent, light ends, and non-condensable gases. The process further comprises the step of separating the crude product stream to form a cooled vapor stream and at least one condensed crude product stream without the addition of heat. The process further comprise the step of separating at least a portion of the condensed crude product stream to form an alkylenating agent stream comprising at least 1 wt. % alkylenating agent and the intermediate product stream comprises acrylate product. | 04-04-2013 |
| 20130165695 | PROCESS CONDITIONS FOR PRODUCING ACRYLIC ACID - In one embodiment, the invention is to process for producing acrylics. The process includes the steps of contacting a crude product stream with an extraction agent mixture. The weight ratio of the extraction agent mixture to the crude product stream is greater than 0.25:1. | 06-27-2013 |
| 20130253224 | Process for Producing Acrylic Acids and Acrylates - In one embodiment, the invention is to process for producing acrylics. The process includes the steps of contacting a crude product stream with an extraction agent mixture and diluting the crude product stream with at least one diluent. | 09-26-2013 |
| 20130274518 | Purification Of Bio Based Acrylic Acid To Crude And Glacial Acrylic Acid - 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. | 10-17-2013 |
| 20130274519 | THERMAL SEPARATION PROCESS - A thermal separation process between a gas ascending in a separating column and a liquid descending in the separating column, which comprise (meth)acrylic monomers, wherein the separating column comprises a sequence of crossflow mass transfer trays, the crossflow mass transfer trays of which have passage orifices for the ascending gas in crossflow direction both in front of and beyond a downcomer for the descending liquid, and such crossflow mass transfer trays and one such crossflow mass transfer tray in a sequence of crossflow mass transfer trays present in a separating column. | 10-17-2013 |
| 20130274520 | Purification Of Bio Based Acrylic Acid To Crude And Glacial Acrylic Acid - 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. | 10-17-2013 |
| 20130281737 | METHOD FOR REDUCING EQUIPMENT FOULING IN (METH)ACRYLIC ACID PRODUCTION PROCESS - The present invention provides a method for reducing fouling of equipment during separation and purification steps of (meth)acrylic acid production by early removal of aldehyde impurities by adding a hydrazide compound well upstream of the separation and purification steps. In particular, carbodhydrazide may be added as an aldehyde scavenging agent to aqueous (meth)acrylic acid prior to dehydration and purification steps. | 10-24-2013 |
| 20140066652 | PROCESS FOR PRODUCING (METH)ACRYLIC ACID - A process for producing (meth)acrylic acid comprising the step of repeating a crystallization operation “n” times to produce purified (meth)acrylic acid from crude (meth)acrylic acid, wherein: the each crystallization operation comprises a crystallizing step and a melting step; a polymerization inhibitor is not added to a (meth)acrylic acid melt obtained in the melting step of the first to n−1 | 03-06-2014 |
| 20140187817 | PREPARATION OF METHACRYLIC ACID - The invention relates to a process for preparation of methacrylic acid, comprising process steps a) providing a crude methacrylic acid-comprising aqueous solution comprising at least one impurity at least partially dissolved therein; b) precipitation of at least a part of the at least one impurity from the crude methacrylic acid-comprising aqueous solution to form at least one solid impurity and a mother liquor; c) separation of at least a part of the at least one solid impurity from the mother liquor to obtain a purified methacrylic acid-comprising aqueous solution and a solid impurity; d) separation of methacrylic acid from the purified methacrylic acid-comprising aqueous solution. | 07-03-2014 |
| 20140200366 | METHOD FOR REDUCING FOULING DURING PURIFICATION OF (METH)ACRYLATE ESTERS - The present invention provides a method for reducing accumulation of solid materials when manufacturing a (meth)acrylic acid ester having low biacetyl content (less than 2 ppm) by adding an aromatic diamine under conditions which provide sufficient residence time and thorough mixing to react up to 100% by weight of the biacetyl in the crude (meth)acrylic acid ester stream, prior to separation and purification. A feedback method is also provided for reducing solids accumulation in the separation and purification equipment of such processes by measuring the biacetyl content and adjusting the aromatic diamine addition rate so that excess aromatic diamine can be minimized. A third embodiment provides a method for reversing an accumulation of solid materials during such processes, while still producing a (meth)acrylic acid ester having low biacetyl content (less than 2 ppm), by reducing or ceasing the addition rate of aromatic diamine for a period of time. | 07-17-2014 |
| 20140221686 | METHOD OF RECOVERING CARBOXYLIC ACIDS FROM DILUTE AQUEOUS STREAMS - Improvement in separating lower carboxylic acids from aqueous streams via liquid-liquid extraction with pressurized liquefied propylene and/or propane, wherein carboxylic acid is transferred from the aqueous phase into the liquid solvent phase (extract). The extracted carboxylic acids are recovered as a liquid concentrate by evaporating off the propylene and/or propane solvent from the extract at mild temperatures. | 08-07-2014 |
| 20140221687 | PROCESS FOR RECLAIMING METHACRYLIC ACID FROM A HIGH-BOILER PHASE AND AN AQUEOUS PHASE - The invention relates to a process for reclaiming methacrylic acid from a high-boiler phase in a heterogeneously catalysed gas phase oxidation of a C4-compound to methacrylic acid comprising the following steps a) Providing a high-boiler phase from a heterogeneously catalysed gas phase oxidation of a C4-compound to methacrylic acid b) Providing an aqueous phase, preferably organically loaded, from a heterogeneously catalysed gas phase oxidation of a C4-compound to methacrylic acid c) Mixing of components a) and b) optionally followed by filtration or centrifugation d) Adding an extraction media to the mixture from c) e) Subjecting the multiple-phase mixture from d) to at least one mixer-settler extraction process f) Recycling the organic phase from the last mixer-settler process back into the C4-process. | 08-07-2014 |
| 20140364646 | METHOD FOR PURIFYING METHACRYLIC ACID - Provided is a crystallization method by which a highly-pure methacrylic acid crystal can be produced with high productivity. The method for purifying methacrylic acid according to the present disclosure involves using crude methacrylic acid having a maleic acid concentration of 2000 ppm by mass or less and an acrylic acid concentration of 2000 ppm by mass or less and setting the slurry temperature to −10 to 10° C. in order to crystallize methacrylic acid. A suspension-type jacket-cooling-system crystallization vessel is used as the crystallization apparatus, and an absolute value of the difference between a crystallization temperature and a temperature of a cooling medium in the jacket is preferably 15° C. or less. | 12-11-2014 |
| 20140371488 | DIVIDED WALL DISTILLATION COLUMN FOR PRODUCING HIGH PURITY ACRYLIC ACID AND FRACTIONAL DISTILLATION METHOD USING THE SAME - There are provided a dividing wall distillation column for producing high-purity acrylic acid, and a fractional distillation method using the same. The dividing wall distillation column includes a condenser, a reboiler and a main column having a dividing wall. Here, the main column is divided into a column-top zone, an upper feed zone, an upper outflow zone, a lower feed zone, a lower outflow zone and a column-bottom zone. Also, a crude acrylic acid raw material (F) flows in a middle inflow plate NR | 12-18-2014 |
| 20140378702 | Processes for Separating Crude Acrylic Acids and Acrylates Comprising A Michael Addition Product - In one embodiment, the present invention is directed to a process for producing an acrylate product. The process comprises the step of reacting, optionally in a reaction zone, a reaction mixture comprising an alkanoic acid and an alkylenating agent under conditions effective to form a crude acrylate product. The crude acrylate product comprises acrylate product and acetic acid. The process further comprises the step of reacting, in a separation zone, at least a portion of the acrylate product and at least a portion of the acetic acid to form an intermediate acrylate product. The intermediate acrylate product comprises a Michael addition by-product, e.g., 3-acetoxypropionic acid and/or 3-acetoxypropanoic acid. The process further comprises the step of separating at least a portion of the intermediate acrylate product to form a by-product stream and a purified acrylate product stream. | 12-25-2014 |
| 20150018576 | METHOD AND DEVICE FOR THE HYDROFORMYLATION OF ISOBUTENE AND FOR THE SEPARATION OF THE PRODUCT MIXTURE - The invention relates to a method for producing a product mixture ( | 01-15-2015 |
| 20150299107 | SELECTIVE EXTRACTION OF AN OMEGA-FUNCTIONALIZED ACID AFTER OXIDATIVE CLEAVAGE OF AN UNSATURATED FATTY ACID AND DERIVATIVES - The invention relates to a process for the selective extraction of a reaction product, derived from an oxidative cleavage of an unsaturated fatty acid or of an ester derivative or of an unsaturated nitrile derivative, said reaction product being an ω-functionalized acid from among C | 10-22-2015 |
| 20150368177 | PROCESS FOR PURIFYING (METH)ACRYLIC ACID - A process for producing a grade of (meth)acrylic acid having residual formaldehyde levels of under 100 parts per Million. | 12-24-2015 |
| 20160031793 | Purification Of Bio Based Acrylic Acid To Crude And Glacial Acrylic Acid - 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. | 02-04-2016 |
| 20160145185 | METHOD FOR CONTINUOUS RECOVERING (METH)ACRYLIC ACID AND APPARATUS FOR THE METHOD - This disclosure relates to a method of continuous recovery of (meth)acrylic acid and an apparatus used for the recovery method. The method of continuous recovery of (meth)acrylic acid according to the present invention may effectively remove scum formed in the continuous recovery process of (meth)acrylic acid, and simultaneously recover (meth)acrylic acid with excellent efficiency, thus enabling more stable operation of the continuous process. | 05-26-2016 |
| 20160200656 | PROCESS FOR CONTINUOUS RECOVERING (METH)ACRYLIC ACID AND APPARATUS FOR THE PROCESS (As Amended) | 07-14-2016 |
| 20160200657 | PROCESS FOR CONTINUOUS RECOVERING (METH) ACRYLIC ACID AND APPARATUS FOR THE PROCESS | 07-14-2016 |
| 20160376214 | PROCESS FOR CONTINUOUS RECOVERING (METH)ACRYLIC ACID AND APPARATUS FOR THE PROCESS (As Amended) - This disclosure relates to a method for continuous recovery of (meth)acrylic acid and an apparatus used for the recovery method. The method of continuous recovery of (meth)acrylic acid according to the present invention may remarkably reduce the amount of extraction solvent used and energy consumption of the total process, and minimize polymerization of (meth)acrylic acid in the recovery process, thus enabling stable recovery of (meth)acrylic acid and operation of a continuous process. | 12-29-2016 |
| 20180022680 | METHOD FOR PRODUCING ACRYLIC ACID | 01-25-2018 |
