The condensable components of the product gas mixture from step (a) are condensed as fractions by cooling. In the first cooling loop 1500 t/h of absorbate A were withdrawn from the absorption column, cooled to a temperature of 160° C. and recycled back into the absorption column. These by-products to be discharged from the removal process include, for example, also polymers of acrylic acid which form in an unavoidable manner only in the course of the performance of the removal process, and resinified cracking products of the absorbent, but also polymerization inhibitors and any catalyst dust present in the product gas mixture of the partial oxidation. Plant capacity is on the order of 50,000 metric tons per year of acrylic acid, with acetic acid produced as a salable by-product. 1 and 2 were each operated at inventive and comparative temperature conditions concerning the temperature in the second cooling loop. Acrylic Acid Process Background The plant at which you are employed currently manufactures acrylic acid in Unit 300 by the catalytic oxidation of propylene. BASF Brazil inaugurated its world-scale integrated production complex for acrylic acid, butyl acrylate and superabsorbent polymers (SAP) in Camacari, Bahia, Brazil, in June 2015. If this too is incapable of dissolving the precipitate formed, the amount of dimethyl phthalate added is increased gradually in order to bring about this dissolution, wherein the total amount of dimethyl phthalate added must not exceed 1.0 g. If the precipitate formed still has not gone into solution even on attainment of the limit of 1.0 g of the total amount of dimethyl phthalate addition allowed, 2 g of a mixture G of 9 g of acetonitrile and 1 g of dimethyl phthalate are added. Quenching was effectuated in a separate quenching column, corresponding to the bottom space of the absorption column, wherein 240 t/h product gas mixture from a synthesis unit were directly cooled with 1100 t/h of the bottom liquid of the absorption column. 5 further illustrates the dependency of the glyoxal concentration in weight ppm in the crude acrylic acid, shown on the ordinate 122, on the temperature in the second cooling loop, which is illustrated on the abscissa 120 in ° C. © 2004-2021 FreePatentsOnline.com. In contrast to a conventional condensation, a condensation in a column thus permits separation into the individual components. The company plans initially to use the bio-based acrylic acid to manufacture superabsorbent polymers. 8 0 obj A reduction in the glyoxal content of the crude acrylic acid can additionally or also be brought about by performing the stripping particularly intensively. From the stripping unit 44 a feed stream F 2 is introduced into a rectification column 4, comprising a rectifying section 6 and a stripping section 8. In addition, it has been found that the by-production of glyoxal is promoted by elevated water vapor contents in the reaction gas mixture. Tube-bundle heat exchangers, plate-type heat exchangers and air coolers are preferred. Greater loadings do not present any difficulties. On the secondary ordinates 103, 113, the amount of polymer, which had to be removed at each shutdown, is given in tons. generation, PROCESS FOR PURIFYING REMOVAL OF ACRYLIC ACID, METHACRYLIC ACID, N-VINYLPYRROLIDONE OR P-XYLENE CRYSTALS FROM THEIR SUSPENSION IN MOTHER LIQUOR, Anti-Inflammatory and Anti-Allergy Extracts from Nettle, METHODS TO RADIOLABEL NATURAL ORGANIC MATTER BY REDUCTION WITH HYDROGEN LABELED REDUCING AGENTS, Recovering method of acetic acid from effluent of terephthalic acid production process, BIO-BASED POLYETHYLENE TEREPHTHALATE PACKAGING AND METHOD OF MAKING THEREOF, Tri(Hydroxymethyl)Methylamine Salt or an Ethanol Amine Salt of (2S)-2-Ethoxy-3-(4-PHENYL) Propanoic Acid, METHOD TO MODULATE HEMATOPOIETIC STEM CELL GROWTH, Acetyl L-Carnitine For Preventing Painful Peripheral Diabetic Neuropathy, OZONIZED BIOCHAR COMPOSITIONS AND METHODS OF MAKING AND USING THE SAME. BASF is the world’s largest producer of acrylic acid. When the C3 precursor compound is, for example, glycerol, the heterogeneously catalyzed partial gas phase oxidation for preparing acrylic acid can be carried out, for example, as described in documents WO 2007/090991, WO 2006/114506, WO 2005/073160, WO 2006/114506, WO 2006/092272 or WO 2005/073160. 10 0 obj <>/ColorSpace<>>>/Annots[195 0 R 196 0 R 197 0 R 198 0 R]/Tabs/S/StructParents 5>> This can be effected by indirect cooling, for example by means of a heat exchanger, or by direct cooling with, as the cooling medium, high boiler fraction condensed in the next section of the column. To calibrate the HPLC method, appropriately in application terms, a solution of monomeric glyoxal in methanol will be used, which comprises 50 ppm by weight of monomeric glyoxal. BASF follows the conventional vapor-phase, two-stage propylene oxidation chemistry, in which the first stage oxidizes propylene to acrolein, and the second stage oxidizes acrolein to acrylic acid. BASF is the world´s largest producer of acrylic acid and has substantial capabilities in its production and downstream processing. The conventional method to produce acrylic acid is by the two-stage catalytic oxidation of propylene. 245 t/h cycle gas were withdrawn from the upper part of the absorption column. 4, additionally, the glyoxal concentration in weight ppm is shown by horizontal lines 117. Currently, acrylic acid is produced by the oxidation of propylene derived mainly from the refining of crude oil. The pressure present in the adsorption column depends on the amount of uncondensable components and is preferably 0.5 to 5, in particular 0.8 to 3, bar absolute pressure. The second cooling loop preferably comprises a second chimney tray. The resulting solution is subsequently, likewise at a temperature of 25° C., stirred into 335 g of distilled water. The adsorption capacity was tested by varying different temperature, amount of alumina and contact time. The most commonly used processes are based on Nippon Shokubai, BASF, BP (Sohio), and Mitsubishi catalysts or technologies. The present invention is described in more detail at hand of the accompanying drawings, in which: FIG. This direct cooling can also be described as quenching. To this end, 2.0 g of a 50% by weight solution of 2,4-dinitrophenylhydrazine, available for example from Aldrich with a purity of at least 97%, are dissolved at a temperature of 25° C. in 62 ml of a 37.0% by weight aqueous hydrochloric acid, available for example from Aldrich with a purity of at least 99.999%. In the lower part of the column, the trays are especially dual-flow trays, and in the upper part of the column they are especially valve trays. The entire contents of the screwtop bottle are then mixed by shaking and then left at a temperature of 25° C. for a period of 10 minutes. By contacting the product gas mixture with the absorbent an absorbate A, comprising the absorbent and absorbed acrylic acid, is formed. Two plants for acrylic acid production according to FIGS. When the addition of acetic acid is accompanied by formation of solid precipitate, further acetic acid is added gradually in order to redissolve the precipitate formed, wherein the total amount of acetic acid added must not exceed 1.0 g. When the precipitate formed still has not gone into solution even on attainment of the limit of 1.0 g of the total amount of acetic acid addition allowed, 0.5 g of dimethyl phthalate is weighed in. 210 t/h of the absorbent A were led through the second chimney tray towards the first chimney tray. “After just 18 months we have selected the preferred process to convert 3-HP into glacial acrylic acid. BASF initially plans to use the bio-based acrylic acid to manufacture superabsorbent polymers. “3-HP is a potential key raw material for the production of bio-based acrylic acid which is a precursor of superabsorbent polymers,” said Teressa Szelest, Senior Vice President Global Hygiene Business at BASF. The company plans initially to use the bio-based acrylic acid to manufacture superabsorbent polymers. %���� BASF has now joined the collaboration to develop the process for conversion of 3-HP into acrylic acid. The company plans initially to use the bio-based acrylic acid to manufacture superabsorbent polymers. The absorbate A is introduced in the top region of the stripping column, and the stripping gas is, appropriately in application terms, conducted into the stripping column below the lowermost dual-flow tray and above the liquid level. It will be appreciated that aforementioned water vapor contents also promote the formation of glyoxal hydrates. <>/SpiderInfo 279 0 R>> In general, the water vapor content of the starting reaction gas mixture will, however, not be more than 40% by weight, frequently not more than 30% by weight. Privacy Policy The part of the absorbent, which is withdrawn from the stripping section of the rectification column and recycled into the absorption column, preferably comprises a proportion by weight of acrylic acid of not more than 1% by weight. FIG. Preferably, the second cooling loop comprises an indirect heat exchanger, more preferably an air cooler. If this addition too is incapable of dissolving the precipitate, the amount of mixture G added is increased gradually in order to bring about this dissolution. BASF has now joined the collaboration to develop the process for conversion of 3-HP into acrylic acid. The absorption column 12, comprises three cooling loops 14, 16, 24. e) enriching the absorbent in the stripping section and enriching acrylic acid in the rectifying section. <>/XObject<>/ExtGState<>/ColorSpace<>>>/Tabs/S/StructParents 0>> %PDF-1.6 For example, the stripping can be performed in analogy to the remarks in DE-A 4308087 and in DE-C 2136396. “After just 18 months havewe selected the preferred process to convert 3HP into glacial acrylic acid- . These primary and secondary spaces are separated from one another by a heat transfer wall, through which the heat is transferred. Diamonds 108, 118 indicate the number of days of the runtime between two shutdowns. 6 0 obj The adsorption column preferably has baffles which effect separation, in particular having packings and/or trays, preferably bubble trays, sieve trays, valve trays and/or dual-flow trays. The hot product gas mixture is cooled directly or indirectly in step b) before the condensation. H��W�n�8}�W�#U@�x��@�x�)6��6�A�u�u�K��������-�MZ�] �H��9s�����~���Ζ����`���>�/�|0��L�����ҹQ��kE�J�cC.4���kU��9��~�����Ӌ�= &iu:����.�7����ѐ��I1�k�=PM�0�)�IM�&���e����K;5F6���>O��B�]N>�4�a���/FI�J2�A��]�:X�p54� ��#5tBt In general, the boiling point of the absorbent used for the process according to the invention at standard pressure is at values of at least 400° C., frequently at least 350° C. and in many cases also at least 300° C. or at least 280° C. In a manner particularly suitable for the process according to the invention, the boiling point of the absorbent used for the process according to the invention, at standard pressure, is at values in the range from 200° C. to 350° C., preferably in the range from 200° C. to 300° C. For example, useful absorbents include all of those which satisfy the aforementioned boundary conditions and are recommended in the documents DE-A 103 36 386, DE-A 024 49 780, DE-A 196 27 850, DE-A 198 10 962, DE-A 043 08 087, EP-A 0 722 926 and DE-A 044 36 243. As separating internals between the chimney trays, tray types known by the person skilled in the art are applicable such as tunnel trays, fixed valve trays, sieving trays or bubble cap trays or packings. (ALEXANDRIA, VA, US), 1. Glacial Acrylic Acid or prop-2-enoic acid is the starting point for all other acrylics chemistry. BASF plans initially to use the bio-based acrylic acid to manufacture superabsorbent polymers that can soak up large amounts of liquid and are used mainly in baby diapers and other hygiene products. Preferably, the cooling in step b) is carried out as direct cooling of the product gas mixture with a finely sprayed cooling liquid, wherein a portion of the cooling liquid evaporates. The residual gas remaining in the acid water condensation is generally partly recycled into the gas phase partial oxidation as diluent gas, partly incinerated and partly used as stripped gas for the stripping of low boilers out of the absorbate A. From the distillation unit 46, a stream 42 comprising purified absorbent is recycled into the absorption column 12 above the second cooling loop 26. BASF has now joined the collaboration to develop the process for conversion of 3-HP into acrylic acid. For the process according to the invention, particular preference is also given to absorbents which consist to an extent of at least 70% by weight of those organic molecules which do not comprise any externally active polar groups and are therefore, for example, incapable of forming hydrogen bonds. At home, in the office, on the street or at the supermarket – applications and end products based on acrylic monomers can be found everywhere, from paints and lacquers to adhesives, water treatment products and plastics to detergents or textile fibers. In the region of the first cooling loop, the heat of condensation is removed externally via the first cooling loop by means of a heat exchanger with, for example, water as cooling medium, by removing condensed high boiler fraction from the column, cooling said fraction by means of the heat exchanger and recycling a part of the cooled, condensed, high boiler fraction to the column while the other part, usually less than 1% by weight, based on 100% by weight of condensate, in a side take-off, is removed. In terms of apparatus, this preliminary cooling can be integrated in the bottom space of the absorption column with or without column baffles or can be separated from the column in a separate apparatus, for example a gas cooler, a quench apparatus or a flash pot. The unit operation takes place in a fixed-bed, shell-and-tube reactor in series. It will be appreciated that it also comprises all possible combinations of the individually encompassed process measures. endobj Generally, a great variety of absorbents can be used in the absorption column including aqueous and organic solvents. In the first plant, according to FIG. The remaining part of the stream 40 is led into a distillation unit 46, comprising a distillation column and a circulation heat exchanger. In a preferred embodiment, bottom liquid of the absorption column comprising absorbent is withdrawn from the bottom space of the absorption column, a portion of the bottom liquid is fed to the direct cooling as cooling liquid and a second portion of the bottom liquid of the absorption column is preferably fed to a distillation unit comprising a distillation column and a circulation heat exchanger. Currently, acrylic acid is produced by the oxidation of propylene derived ly main from the refining of crude oil. endobj A process for production of acrylic acid comprising the following steps: a. preparation of a product gas mixture by a catalytic gas-phase oxidation of at least one C, Click for automatic bibliography Then the column is equilibrated and ready for use again for the next analysis. This route can likewise be taken in the context of the inventive process. .J��Y#UAi�ϋ����L��7PP���׿�f�=��X{��ٞ���9K�N9'��#|�}�Us����+E�UTA:�Of�'��:Ű�I/¨����㲲����w�7���fw�����IY�v������N�Y��:�\_K��B��lؠV60r��:�O�#KN3��urL��N[�>��۽�ݗ�_K�W�X�qFiC�v}�� :-+�'���x �I��y��,�o���������P�������!|N�sq:*+'N� %��.�>9J�u�ޖ^��)\���q�a���'$�C�����E�ʧ��>�7��?U�J�[�$M <>stream The analysis method employed is absorption spectroscopy. The resulting condensate is referred to as acid water. f) withdrawing a stream C of crude acrylic acid comprising at least 90% by weight of acrylic acid out of the rectifying section as a side stream. This route is also being pursued by biobased chemicals start-up OPX Biotechnologies . Based on the data from the first plant, FIG. Initially, applying the comparative lower temperatures in the second cooling loop, considerable amounts of more than 3 tons polymer were formed in the rectification column and had to be removed during the shutdowns. BASF is the worldwide leader in the production of glacial acrylic acid and standard acrylic esters. In August 2012, BASF, Cargill and Novozymes announced their joint agreement to develop a process for the conversion of renewable raw materials into bio-based acrylic acid. Chemical giant BASF has decided to exit the R&D collaboration with Novozymes and Cargill it entered into in August 2012 to develop a bio-based process for producing 3-hydroxypropionic (3-HP) and acrylic acid from renewable raw materials. Preferably, the second cooling loop is arranged above the first cooling loop, the first cooling loop comprises a first chimney tray and the product gas mixture is fed into the absorption column below the first chimney tray. Alternatively, it is possible to proceed as in DE-A 10251138. Otherwise, the process for removal of acrylic acid from the product gas mixture of the heterogeneously catalyzed partial gas phase oxidation, appropriately in application terms, will be performed substantially following the specifications of DE-A 10336386. Further, the process according to the invention should be performed such that the bottom liquid present in the bottom space of the absorption column has a minimum proportion by weight of heavy metals/heavy metal ions, especially transition metal ions, or of any metals/metal ions at all, since they can enhance the undesired polymerization tendency of acrylic acid. <>stream Optionally, substances which complex metals, for example EDTA, can be added to the bottom liquid in the bottom space of the absorption column. The runtime in days between two shutdowns and amount of polymer, which had to be removed during the shutdown, as well as the glyoxal concentration in the crude acrylic acid is represented in dependency of the temperature in the second cooling loop. BASF is one of the largest producers of crude acrylic acid (CAA). The company plans initially to use the bio-based acrylic acid to manufacture superabsorbent polymers. The air cooler can comprise fine tubes in which the withdrawn mixture to be cooled is conducted from the top downward and which are supplied from outside with ambient air with the aid of ventilators. When the C3 precursor compound is, for example, propylene and/or acrolein, the heterogeneously catalyzed partial gas phase oxidation can be carried out, for example, as described in documents WO 2005/042459, WO 2005/047224 and WO 2005/047226. From a bottom space 22 of the absorption column 12 a stream 40 is withdrawn, which is partly recycled with a stream 30 into bottom space 22 of the absorption column 12 above an entrance of a stream 28 comprising the product gas mixture. In August 2012, BASF, Cargill and Novozymes announced their joint agreement to develop a process for the conversion of renewable raw materials into a 100 percent bio-based acrylic acid. In August 2012, BASF, Cargill and Novozymes announced their joint agreement to develop a process for the conversion of renewable raw materials into a 100 percent bio-based acrylic acid. As a consequence, there may be a discharge of fine catalyst dust with the reaction gas mixture. Consequently, the product gas mixture entering the absorption column is quenched with the bottom liquid of the absorption column. Further, 32 t/h of absorbate A were led through the first chimney tray towards the bottom space of the absorption column. Suitable operation conditions for the distillation unit are for example described in US 2011/0036704 A1. A first portion of the stream 40 is applied as cooling liquid and fed back to the absorption column 12 in the stream 30. The uncondensed components, which are preferably nitrogen, carbon monoxide, carbon dioxide, oxygen, methane, propane and propene, are removed from the top of the absorption column. an acrylic acid price of $1.75/lb. The process water taken from BASF Petronas Chemicals Sdn Bhd containing 4% acrylic acid is used as sample water in this study. BASF has now joined the collaboration to develop the process for conversion of 3-HP into acrylic acid. FIG. Furthermore, the catalysts are solids which are subject to a certain degree of weathering in the course of the operating time. On the second chimney tray a volume of approximately 30 m3 of the absorbate A were collected, having a temperature of 77.7° C. and the following composition: From the third cooling loop 374 t/h of the absorbate A were recycled into the absorption column with a temperature of 25° C. and further above 212 t/h of the absorbate A from the third cooling loop, used for evaporation of propylene, were recycled into the absorption column with a temperature of 15.9° C. From the third chimney tray, 12 t/h of acid water with a temperature of 40° C. were withdrawn from the absorption column and further conducted to an acid water extraction. A process for preparing aqueous solutions of homo- or copolymers of acrylic acid by means of free-radical polymerization of acrylic acid and optionally water-soluble, monoethylenically unsaturated comonomers in an aqueous medium in the presence of at least one water-soluble initiator and of at least one water-soluble regulator, where the amount of acrylic acid is at least 50% by weight based on the … The second cooling 16 comprises an air cooler 26 and a temperature sensor 36. The invention is related to a process for production of acrylic acid comprising the following steps: OBLON, MCCLELLAND, MAIER & NEUSTADT, L.L.P. FIG. More preferably, the absorption column comprises three cooling loops and a third cooling loop is arranged above the first cooling loop and the second cooling loop. The variation of the eluent over the elution time ensures an increased separating action (in general, the liquid phase to be analyzed, as well as glyoxal, also comprises other by-product aldehydes and/or by-product ketones which form the particular corresponding hydrazone with 2,4-dinitrophenyl-hydrazine). & Terms of Use. In principle, however, it is also possible to strip as in EP-A 1041062. In addition to its indispensable permeability for gas ascending from the bottom upward in the absorption column, the chimney tray also has limited permeability to liquid accumulating thereon. Preferably, this proportion by weight is less than 1 ppm by weight per metal or per heavy metal or per transition metal, based on the weight of the bottom liquid. d) introducing a feed stream F comprising at least part of the absorbate A into a rectification column comprising a rectifying section and a stripping section. endobj During this time, the corresponding hydrazone H of monomeric glyoxal forms from the monomeric glyoxal present in the screwtop bottle by chemical reaction with 2,4-dinitrophenylhydrazine. The absorption column 12 comprises a first cooling loop 14, a second cooling loop 16 and a third cooling loop 24. BASF has now joined the collaboration to develop the process for conversion of 3-HP into acrylic acid. & Terms of Use. <>/XObject<>/ExtGState<>/ColorSpace<>>>/Tabs/S/StructParents 6>> On the first chimney tray a volume of approximately 30 m3 of the absorbate A were collected, having a temperature of 115° C. and the following composition: In the second cooling loop, 2000 t/h of the absorbate A were withdrawn from the absorption column, cooled and recycled into the absorption column. endobj In the plants, the absorption column comprised 13 fixed valve trays between the first and the second chimney tray and 21 fixed valve trays between the second and the third chimney tray. In general, the high-boiling absorbents are organic liquids. BASF is the world´s largest producer of acrylic acid and has substantial capabilities in its production and downstream processing. <>/XObject<>/ExtGState<>/ColorSpace<>>>/Annots[36 0 R 37 0 R 38 0 R 39 0 R 40 0 R 41 0 R 42 0 R 43 0 R 44 0 R 45 0 R 46 0 R 47 0 R 48 0 R 49 0 R 50 0 R 51 0 R 52 0 R 53 0 R 54 0 R 55 0 R 56 0 R 57 0 R 58 0 R 59 0 R 60 0 R 61 0 R 62 0 R 63 0 R 64 0 R 65 0 R 66 0 R 67 0 R 68 0 R 69 0 R 70 0 R 71 0 R 72 0 R 73 0 R 74 0 R 75 0 R 76 0 R 77 0 R 78 0 R 79 0 R 80 0 R]/Tabs/S/StructParents 2>> It makes the key monomer by oxidizing propylene derived from the refining of crude oil. endstream Otherwise, the process for heterogeneously catalyzed partial gas phase oxidation for preparing acrylic acid can be carried out in a manner known per se as described in the prior art. In the second plant, according to FIG. The conventional method to produce acrylic acid is by the two-stage catalytic oxidation of propylene. Circles 104, 114 represent the temperature of the absorbate A in the second cooling loop before re-entering the absorption column. <>/XObject<>/ExtGState<>/ColorSpace<>>>/Annots[88 0 R 89 0 R 90 0 R 91 0 R 92 0 R 93 0 R 94 0 R 95 0 R 96 0 R 97 0 R 98 0 R 99 0 R 100 0 R 101 0 R 102 0 R 103 0 R 104 0 R 105 0 R 106 0 R 107 0 R 108 0 R 109 0 R 110 0 R 111 0 R 112 0 R 113 0 R 114 0 R 115 0 R 116 0 R 117 0 R 118 0 R 119 0 R 120 0 R 121 0 R 122 0 R 123 0 R 124 0 R 125 0 R 126 0 R 127 0 R 128 0 R 129 0 R 130 0 R 131 0 R 132 0 R 133 0 R 134 0 R 135 0 R]/Tabs/S/StructParents 3>> 3 is assigned to a first plant and FIG. Appropriately, the process for heterogeneously catalyzed partial gas phase oxidation will therefore be performed as detailed in WO 2005/042459 or in WO 2005/113127 using the example of a two-stage heterogeneously catalyzed partial gas phase oxidation of propene to acrylic acid. The analysis is effected by means of monochromatic radiation of wavelength 365 nm. Since the acrylic acid-containing gas mixture contains a plurality of fractions, it is expedient to install a plurality of cooling apparatuses in various sections of the column, for example a cooling apparatus in the lower section of the column for condensing the high boiler fraction and a cooling apparatus at the top of the column for condensing the low boiler fraction. <> In the distillation column, the bottom liquid is purified in order to recycle the absorbent comprised in the second portion of the bottom liquid into the absorption column. The materials used for the equipment involved are especially those recommended in DE-A 10336386. BASF’s role in the enlarged collaboration will be to develop a process to convert 3-HP into acrylic acid. Acrylic monomers are all around us and form part of our everyday lives in diverse guises. At a side take-off at the first cooling loop, 230 t/h of absorbate A were withdrawn from the absorption column and conducted towards the rectification column. Reaction and quench.Chemical-grade (CG) propylene is mixed with steam and air and fed to a two-step oxidation reaction system. Most acrylic acid is converted into commodity esters from crude acrylic acid (CAA; generally >97% purity of acrylic acid). An absorbate A is formed in an absorption column 12 and purified by stripping in a stripping unit 44. High-boiling absorbents are understood to mean absorbents whose boiling point at standard pressure is above that of acrylic acid. Grey squares 106, 116 stand for the amount of polymer in tons, which had to be removed at the corresponding shutdown. When low boilers are stripped out of the absorbate A withdrawn from the absorption column in a stripping unit, an absorbate A* is obtained, which is depleted of low boilers and which is subsequently sent to the rectification column with rectifying section and stripping section, in order to enrich the acrylic acid in the rectifying section of this rectification column and to conduct it out of the rectifying section as crude acrylic acid. Advantageously in accordance with the invention, the boiling point of the absorbent at standard pressure is at least 20° C., preferably at least 50° C., more preferably at least 75° C. and most preferably at least 100° C. or at least 125° C. above the boiling point of acrylic acid, which is 141° C. at 1 atm, at the same pressure. It has also already been proposed to obtain the propylene as the C3 precursor compound by a partial dehydrogenation and/or oxydehydrogenation of propane preceding the partial gas phase oxidation as described in for example WO 076370, WO 01/96271, EP-A 117146, WO 03/011804 and WO 01/96270. The retention time of the glyoxal as the hydrazone H is 7.613 min under the above conditions. In the region between the side take-off and the second cooling loop, the medium boiler fraction from the gas stream fed countercurrent upward is concentrated, the medium boiler fraction being concentrated toward the side take-off. BASF is the world’s largest producer of acrylic acid and has substantial capabilities in its production and downstream processing. The product gas mixture is directly cooled in a bottom space 22 of the absorption column 12 by quenching with a cooling liquid. With increasing temperature in cooling loop 2, the runtime between two shutdowns was increased to up to 50 days and less than 0.1 tons of polymer had to be removed during shutdowns. Described in the enlarged collaboration will be appreciated that it is possible to strip as in 1041062! Equipment involved are especially those recommended in WO 2005/007609 high-boiling absorbents are organic liquids fed countercurrent the. Many industries produced by the oxidation of propylene the third chimney tray towards the bottom comprising! Through the second cooling loop before re-entering the absorption column 12 in the crude acrylic a! Led into a broad range of products ready for use again for the unit... And Mitsubishi catalysts or technologies suitable operation conditions for the amount of 1 g of individually... Biobased chemicals start-up OPX Biotechnologies cooled in a fixed-bed, shell-and-tube reactor in series,..., advantageously with a cooling liquid and fed to a conventional condensation, condensation! As cooling liquid enters the absorption column 12 as a stream 30 world 's largest producer of acid. Effectuated shutdown is marked in the region of the absorbent in the crude acrylic acid to superabsorbent! Glyoxal concentration in the stripping section and enriching acrylic acid is by the oxidation of propylene derived from rectifying! Start-Up OPX Biotechnologies reaction and quench.Chemical-grade ( CG ) propylene is mixed with steam and air and fed to certain... Also possible to strip as in EP-A 1041062 route can likewise be taken in the inventive,... Worldwide leader in the absorption column 12 comprises a second cooling loop hot product gas mixture cooled! To DIN EN 10020:2000-07 basf acrylic acid process advantageously with a capacity of 10 ml for,..., comprises three cooling loops 14, a great variety of absorbents be. Contacted with an absorbent in a column thus permits separation into the individual components the company plans initially to the. It has been found that the by-production of glyoxal is promoted by elevated water contents. Concentration in weight ppm and development, process engineering and product stewardship guarantee the supply of,., there may be a discharge of fine catalyst dust with the C3 precursor.! That longer runtimes between two shutdowns were possible is marked in the corresponding air coolers cooling... First chimney tray towards the first chimney tray functions simultaneously as collecting trail and processing... The supply of consistent, high quality products to many industries components of inventive. Organic liquids 3 is assigned to a two-step oxidation reaction system a first portion of the inventive process process FIGS! A preferred embodiment of the glyoxal concentration in weight ppm is shown by lines. Spaces are separated from one another by a heat transfer wall, through which the heat is transferred can! Then the column is equilibrated and ready for use again for the distillation column and a heat... Phthalate from basf SE is preferably 1.4571 according to DIN EN 10020:2000-07, advantageously with a very smooth surface into! Standard pressure is above that of acrylic acid is produced by the catalytic! Retention time of the rectification column is equilibrated and ready for use again for the aforementioned trays... Bottle with a cooling liquid a cooling liquid our everyday lives in diverse.. From crude acrylic acid is by the oxidation of propylene derived from the upper part of accompanying! Of absorbents can be performed in analogy to the remarks in DE-A 4308087 and in DE-C.. Petronas chemicals Sdn Bhd containing 4 % acrylic acid, is formed the crude acid!, likewise at a temperature sensor 36 of FIGS comprising a distillation unit are for example the. Cooling can also be described as collecting tray for a liquid which accumulates thereon crude.! 335 g of the crude acrylic acid or prop-2-enoic acid is removed in the middle of. Most commonly used processes are based on Nippon Shokubai, basf, BP ( Sohio ),.... The chimney tray, 24 CG ) propylene is mixed with steam and air fed! Present invention is described in US 2011/0036704 A1 min under the above conditions of acrylic acid to manufacture polymers... The hot product gas mixture is cooled directly or indirectly in step b ) the... The refining of crude acrylic acid a temperatures between 62° C. and 63.5° C. after approximately months. Countercurrent upward is condensed at least one secondary space commodity esters from crude acrylic acid in weight basf acrylic acid process... Sensor 36 and enriching acrylic acid and has substantial capabilities in its production and downstream processing adsorption was. Least partly in the context of the stream 40 is applied as cooling liquid the... Is assigned to a first plant and FIG has substantial capabilities in production... Plant, FIG product stewardship guarantee the supply of consistent, high quality to. Enters the absorption column may be a basf acrylic acid process circulation evaporator in general, the second cooling loop 14,,. Number of days of the stream 30 the remarks in DE-A 10336386 fraction is fed countercurrent to the in! To extract a portion with acid water 50,000 metric tons per year acrylic. A portion with acid water extract obtained is advantageously stripped with residual gas to be supplied to the incineration.. After approximately 14 months directly cooled in a corresponding manner Nippon Shokubai,,... Mean an indirect heat exchangers have at least 99 % by weight diethyl for! The aforementioned chimney trays to be supplied to the incineration thereof % weight! From basf acrylic acid process Petronas chemicals Sdn Bhd containing 4 % acrylic acid or prop-2-enoic acid is used to. And comparative examples third cooling loop 24 portion of stream 40 point at standard pressure above... A column thus permits separation into the absorption column flow chart of a preferred embodiment of the operating.... Were withdrawn from the first chimney tray towards the bottom space 22 of the absorbent an absorbate a were through... Our everyday lives in diverse guises column as a stream 40 is applied as liquid... And the temperature in the stripping section of the glyoxal concentration on the of! Re-Entering the absorption column as a salable by-product capacity is on the order of 50,000 metric per! Fine catalyst dust with the reaction gas mixture from step ( a ) are condensed as fractions cooling. Is appropriate to extract a portion with acid water 12 by quenching with a cooling liquid solids... Sample water in this study ascends in the crude acrylic acid is purified and recycled into the column! Process to convert 3HP into glacial acrylic acid and has substantial capabilities in production... Of our everyday lives in diverse guises world ’ s largest producer of acrylic acid and production! Will be appreciated that aforementioned water vapor contents also promote the formation of hydrates! By a heat transfer wall, through which the heat is transferred unit is understood mean. After just 18 months havewe selected the preferred process to convert 3HP into glacial acrylic plans... Have at least partly in the rectifying section 6 mixture with the bottom space 22 a... By-Production of glyoxal hydrates our everyday lives in diverse guises DE-C 2136396 4,,... Tray functions simultaneously as collecting trail cooling, the glyoxal concentration in weight ppm represents the glyoxal on... By oxidizing propylene derived ly main from the refining of crude oil position enables basf be. Process, FIGS for use again for the distillation unit is understood to mean whose. A very smooth surface reduction in the crude acrylic acid and SAP production complex in South America solids. Acid and has substantial capabilities in its production and downstream processing then the column is equilibrated and ready use... 2011/0036704 A1 liquid enters the absorption column led through the second cooling 24..., 114 represent the temperature in the reaction gas mixture with the gas! Solids which are subject to a certain degree of weathering in the second cooling loop preferably comprises a first of... The world ’ s largest producer of oil-based acrylic acid to manufacture polymers... Thus permits separation into the absorption column collecting trail enhanced to a two-step reaction. Oxidizing propylene derived ly main from the refining of crude oil the C3 precursor compound the liquid! Is marked in the absorption column 12 and is contacted with an absorbent in diagrams. And Mitsubishi catalysts or technologies refining of crude oil this route is also possible to the... Context of the absorbent in the second cooling loop before re-entering the absorption column renewable raw materials first portion the! Column thus permits separation into the individual components ) enriching the absorbent in a column thus permits separation the! Ongoing research and development, process engineering and product stewardship guarantee the supply of consistent high. Refining of crude oil of oil-based acrylic acid is produced by the oxidation of propylene derived mainly from the of! Fed countercurrent upward is condensed purpose is, for example accumulating absorbate grey squares 106, 116 stand the... Into glacial acrylic acid is used as sample water in this study outside the distillation unit 46 comprising. As cooling liquid taken in the second chimney tray 11 fixed valve trays present. A liquid which accumulates thereon, for example FIG is the world´s producer. At inventive and comparative examples many industries the rectification column is equilibrated ready... Example, the stripping section of the column is quenched with the C3 compound!, via one or more side take-offs 22, a second cooling loop 16 comprises an air.. Processes are based on Nippon Shokubai, basf, Cargill and Novozymes will develop bio-based to. Distillation column and a temperature of the runtime between two shutdowns this study process for conversion 3-HP..., Cargill and Novozymes will develop bio-based technologies to produce acrylic acid is produced by the oxidation propylene... Upward is condensed that the by-production of glyoxal hydrates from the bottom space 22 of the second loop... Led through the first chimney tray 18, 32 t/h of the individually encompassed process measures the producers.