Title of Invention	A METHOD OF PURIFYING CAPRYLIC ACID
Abstract	A method of purifying Caprylic acid comprising fractional distillation of fatty acids at temperatures from 70- 115 ° C and corresponding pressures of 0 - 15 mm of Hg so as to selectively remove non-fatty acid material resulting in purified Caprylic acid, substantially free from non-fatty acid material

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FORM 2 THE PATENTS ACT, 1970 (39 OF 1970) & THE PATENT RULES, 2003 SPECIFICATION [SECTION 10 AND RULE 13] "A METHOD OF PURIFYING CAPRYLIC ACID" APPLICANT: GODREJ CONSUMER PRODUCT LTD. NATIONALITY: COMPANY INCORPORATED UNDER THE COMPANIES ACT, 1956 ADDRESS: PIROJSHANAGAR, EASTERN EXPRESS HIGHWAY, VIKHROLI, MUMBAI- 400 079, MAHARASHTRA STATE, INDIA THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE NATURE OF TfflS INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED: The present invention envisages a method of purifying Caprylic acid comprising the steps of distillation. This invention relates to a method of distilling Caprylic acid and more particularly to a method of preliminarily purifying Caprylic acid prior to being distilled. Distillation In the prior art, a process for the nondegenerative distillation of C 6- C 24 fatty acids, of the type obtained by splitting natural fats and oils is known. The crude product is thermally dried under reduced pressure, the dried and heated crude product is subjected to fractional evaporation in falling-film evaporators, optionally in the presence of superheated steam, and the various vapour fractions are deposited in condensers. This process specifically includes fractionating an undistilled whole cut "Laurie" oil fatty acid having 8-20% C 10 or less, 40-52% C 12, 13-19% C 14, 7-12% C 16, and 6-26% C 18's (includes C 18=1 & C 18=2) carbon chain links to form a top cut of C 6- C 12 carbon links followed by an intermediate of C 12 - C 18 carbon links. The C 12 - C 18 is then straight distilled. Further, fractionation or fractional distillation is practiced to separate the whole cut fatty acid, in either distilled or undistilled form, into particular chain lengths. This is accomplished by distilling over only the desired chain length (s) based on their different boiling points. This can be done to varying degrees of purity of separation up to 99%. The resulting fractionated fatty acid will then contain only the specific chains desired for a product application. This can have improvements in odour, colour, viscosity & product performance. 2 The Fatty Acids The fatty acids include fatty acids having about 6-20 carbon atoms dependent on the natural distribution of the hydrocarbons in the oil feedstock. They are obtained by the hydrolysis of natural fats and oils such as vegetable fats and oils. These fatty acids are referred to as whole-cut fatty acids. The resulting whole cut fatty acid is made by "splitting" the oil into fatty acid and glycerine in a hydrolyzer or kettle. The whole cut fatty acid will have the same distribution of carbon chain length molecules as the oil. As is commonly known and as exemplified in Bailey's industrial Oil and Fat Products, Formo et at, Volume 1, Fourth Edition, pages 315 and 318, "Laurie" oils include the following approximate fatty acid chain length distributions: Composition Coconut Oil Fatty Acid Palm Kernel Oil Fatty Acid CIO and less 11-20% 6-12% C12 44-52% 40-52% C 14 13-19% 14-18% C16 8-12% 7-9% C18 6-14% 13-26% Non- Fatty Acid Material Fatty acids derived from the hydrolytic splitting of natural fats or of oils on an industrial scale still contain unsplit fatty acid glycerides and substances of the type which accompany fats, such as sterols, phosphatides, polymerized fatty acids and 3 other decomposition products, and also further impurities. In order to remove the undesirable discoloration, poor colour stability and an unpleasant odour of the products, split fatty acids are subjected to distillation. It has also been known for a long time that, in the straight-run distillation of fatty acids, the quality of the fatty acids obtained from the main distillation stage can be improved, i.e., the amount of undesirable components therein such as carbohydroxides, aldehydes, ketones and peroxides reduced, if these precut (lower boiling) components are separated out of the crude fatty acid in a preliminary step prior to reaching the main distillation stage. The lower boiling components result from oxidative and / or thermal conditions to which the crude fatty acids are subjected prior to and during the distillation thereof such as during oil and fat removal steps, cleaning storage and separation steps. During these procedures, the oxidative and thermally sensitive acid components which are more or less unsaturated, are exposed to high thermal and/or oxidative conditions even when the treatment apparatus is well sealed, and small amounts of cleavage products result. This is especially true with crude fatty acids which are very unsaturated, i.e., they have more than one double bond in the molecule, and specifically when the acids are subjected to high temperatures in the distillation apparatus. These cleavage products undesirably appear in the main condensate in prior art processing systems. The Equipment Fractionation of whole cut fatty acids is conventionally accomplished by means of a distillation unit commonly referred to as a "fractionator". The feed stream is heated to a temperature which allows some vaporization to occur upon entry into the vessel. The residual liquid flows down through stripping stages consisting of structured 4 packing to a still pot. The pot temperature is raised to the boiling point of the desired bottoms (longer chain length) product. A portion of the still pot liquid is vaporized. All of the vapour is condensed in the top section, with a portion of this liquid, the reflux, returning to the tower. This reflux is distributed over the upper sections of structured packing which act as rectifying stages. Longer chains are continuously condensed, purified and removed from the pot. Any impurities such as unsplit oil are removed with bottoms. The shorter chains are continuously vaporized, purfied and then condensed and removed in the top section of the tower. The entire process neither creates nor destroys the individual chain lengths present in the feed. The distillate and the bottoms material, if it contains multiple chain lengths, can be accumulated and reprocessed for further subdivision in a separate pass. The yield of specific cuts out of the process is directly proportional to the percentage in the whole cut fatty acid. The specific process conditions for fractionating fatty acids are well known in the art and need not be described in detail. Prior art The specific process conditions for fractionating fatty acids are well known in the art and need not be described in detail. On an industrial scale, distillation is generally carried out at 2 to 10 mm of Hg and at temperatures of 112 'C to up to about 260 °C. (Ullmanns Enzyklopadie der technischen Chemie, Vol 11 pages 533 et seq., Verlag Chemie Weinheim, 1976). Further, in the process of fractional distillation, the concentration of the lower boiling fractions at the head and of the higher boiling fractions in the sump of the column requires a certain number of separation stages. 5 Baffles in the form of plates or column packings are normally used for forming these separation sub-stages. The process of fractional distillation comprises: (a) heating the dried crude product to tan initial bottom temperature of 120 °C to 125 °C under a pressure of 5 mm of Hg to evaporate the lower boiling fraction, (b) passing the vapours through a rectification column, whose packings are S. S, wire mesh and a packing height of 61 cm, (c) controlling the temperature of the column to preferentially condense out single or selectively mixed fraction of fatty acid/s selectively so as to get a high purity fraction (> 90%), (d) distilling the liquid at the reflux head with a reflux ratio set at partial withdrawal & partial recirculation, (e) maintaining the rate of distillation giving sufficient time for the selective separation process ranging from 2-3 hours depending upon the quantities of fatty acid taken, (f) cooling the vapours of the distillate (8TC.) at the head with a water cooled condenser, (g) drawing off the distillate into the sidearm from the reflux head, (h) collecting the distillate in holding vessel also maintained at the same reduced pressure, (i) monitoring the progress of the process by chemical and instrumental analysis, (j) and finally, stopping the distillation after the desired fraction has been collected as monitored by the analysis of the intermediate or residue as the case may be. U. S. Patent No. 4519952 describes a process for separating a fatty acid from a mixture comprising a fatty acid and an unsaponifiable compound, wherein the process 6 comprises contacting the mixture at separation conditions with a molecular sieve comprising a crystalline silica having a silica to alumina mole ratio of at least 12, thereby selectively retaining the fatty acid. The fatty acid is recovered from the molecular sieve by displacement at displacement conditions with a displacement fluid soluble in the feed mixture and having a polarity index of at least 3.5. The said patent does not use any fractional distillation. Moreover, it uses molecular sieves for separating the fatty acids. U. S. Patent No. 5215630 discloses a method of purifying eicosapentaenoic acid and esters of eicosapentanoic acid, comprising (a) fractionally distilling a starting mixture containing eicosapentaenoic acid or esters of eicosapentaenoic acid, wherein the pressure in the distillation columns is maintained at 10 Torr or below and wherein the bottom temperature of the distillation columns is maintained at 210.degree. C. or below. U. S. Patent No. 5024787 describes a process for preparing fatty acid or hydroxy fatty acid esters of an isopropylidene derivative of a polyglycerol. comprising the steps of: (a) reacting a C.sub.l -C.sub.4 -alkyl ester of a C.sub.6 -C.sub.22 -fatty acid or mono- or polyhydroxy fatty acid, in alkaline medium, with one or more hydroxyl-containing isopropylidene derivatives of a polyglycerol, at a temperature in the range of about 140 °C to about 220 °C, 20°C to 120 °C, preferably 40°C to 80 °C, and at a pressure of 950-5 mbar, and removing the resultant C.sub.l -C.sub.4 alcohol by distillation; and (b) recovering the resultant isopropylidene polyglycerol fatty acid or hydroxy fatty acid esters. 7 The present invention differs from the aforesaid patents as the present invention describes a process of purifying Caprylic acid by selective removal of non-fatty acids by fractionally distilling the fatty acids at temperatures from 7C to 11 5 °C and corresponding pressures of 0 - 15 mm of Hg. The Inventive Step An object of the present invention is to achieve a more thorough and reliable separation of the precut or forerunnings (lower boiling components) as compared to methods described in the prior art above. This invention relates to a method of distilling fatty acids, and more particularly to a method of preliminarily purifying Caprylic acid prior to being distilled. The present invention provides a process in which fatty acids, more particularly Caprylic acid of natural origin is freed from undesirable impurities and separated from one another by distillation in high yields in a single stage carried out at low temperatures & pressures and with short residence times, the products obtained being characterized by reproducible colour quality, high colour stability and by a better odour than the fatty acid fractions obtained by known processes. The improvements made in the inventive step, include controlling the temperature of the rectification column between 70 - 115°C at corresponding pressures of 0 - 15 mm of Hg to preferentially condense out the non-fatty acid material in a single or double distillation of the non fatty acid material from a higher boiling fatty acid along with a lower boiling fatty acid whose B. P. is 65 - 110 °C at 0-15 mm of Hg which is near to that of the non-fatty acid material. Mixed fractions are then re-fractionated in the same way as described in the above process steps (a) to (h). 8 One more object of the invention includes identifying the entity to be removed, viz. the non fatty acid material having its physical properties (boiling point 86 °C at 4 mm) and then controlling the fractional distillation. However, other procedures known to those skilled in the art or disclosed herein may be employed without departing from the spirit of the invention or the scope of the appended claims. The following example is only illustrative and not limiting the scope of the above invention. Example: 2 kg. of a fatty acid blend, Palm Kernel Odour Cut rich in Caprylic Acid (approx. 50%) having about 7 - 8 % of non-fatty acid material is taken for processing. The mixture is subjected to a 2-stage fractional distillation at reduced pressure of 4mm of Hg. At that pressure, the boiling points of the fatty acids and the non-fatty acid material are as under: Fatty Acid B. P.° C at 4 mm pressure Caproic Acid C 6 83 Non-fatty Acid Material 86 Caprylic Acid C 8 110 CapricAcid C 10 133 9 In the first stage, about 55% of the material is distilled out maintaining the 0 temperature at 110 C, which is required for Caprylic acid. The distillate (1.1 kg.) contains Caproic, Caprylic, some traces of Capric Acids and all the non-fatty acid material. At the next stage of the distillation, about 15% of the product is distilled, o keeping the temperature at 86 C, so as to recover the maximum amount of Caproic Acid and the non-fatty acid material. The distillate (0.2 kg.) contains almost all the Caproic acid, non-fatty acid material and traces of Caprylic acid. The remaining product contains Caprylic acid > 90%. The samples are analysed for AV, IV, SV, UM % and GLC composition. The final yield of the pure fatty acid is 0.85 kg. having the following analysis: PKodour cut Caprylic Acid Acid Value (AV) 313.96 380.58 Saponification Value (SV) 314.87 381.39 Iodine value (IV) 7.9 1.22 Unsaponiable Matter % (UM%) 7.1 0.5 GLC Composition % Caproic 4.4 0.5 Caprylic 50.3 94.8 Capric 9.2 1.8 Laurie 18.2 1.2 Lauroleic 0.3 0.3 Myristic and above 8.5 0.0 10 This Caprylic Acid is > 90% pure and also has In addition to the said example, the following is the table showing the range of Boiling Points and their corresponding Pressures required to selectively remove the non-fatty acid material. Component Pressure 2 mm Pressure 4 mm Pressure 7 mm Pressure 10mm Pressure 15 mm B. P. in ° C B. P. in ° C B. P. in°C B. P. in ° C B. P. in ° C Caproic Acid C6 72 83 94 99 107 Non-fatty Acid Material • 76 86 97 103 112 Caprylic Acid C8 97 110 121 127 135 Capric Acid C 1O 121 133 145 151 159 The preceding specific embodiments are illustrative of the practice of the invention. It is obvious, however, that other procedures known to those skilled in the art or disclosed herein may be employed without departing from the spirit of the invention or the scope of the appended claims. 11 We Claim; 1. A method of purifying Caprylic acid comprising fractional distillation of fatty acids at temperatures from 70- 115 ° C and corresponding pressures of 0 - 15 mm of Hg so as to selectively remove non-fatty acid material resulting in purified Caprylic acid, substantially free from non-fatty acid material. 2. A method as claimed in Claim 1, wherein said fatty acids are having 6-10 carbon atoms. Dated this 20th day of June 2001 H. W. Kane Applicant's Agent 12

Documents:

239-mum-2000-cancelled pages(3-5-2005).pdf

239-mum-2000-claims(granted)-(3-5-2005).doc

239-mum-2000-claims(granted)-(3-5-2005).pdf

239-mum-2000-correspondence(12-5-2006).pdf

239-mum-2000-correspondence(ipo)-(15-4-2005).pdf

239-mum-2000-form 1(21-3-2000).pdf

239-mum-2000-form 1(3-5-2005).pdf

239-mum-2000-form 19(31-7-2003).pdf

239-mum-2000-form 2(granted)-(3-5-2005).doc

239-mum-2000-form 2(granted)-(3-5-2005).pdf

239-mum-2000-form 26(10-3-2005).pdf

239-mum-2000-form 3(21-3-200).pdf

239-mum-2000-form 3(23-7-2001).pdf

239-mum-2000-form 3(3-5-2005).pdf

239-mum-2000-form 4(20-6-2001).pdf

239-mum-2000-form 5(20-6-2001).pdf

239-mum-2000-other documents(3-5-2005).pdf

239-mum-2000-power of authority(21-3-2000).pdf