Abstract:
The process utilizes the adsorbent column system as a treatment after chemical refining or before physical refining rather than water or filtration, respectively, to remove soaps and other impurities entrained in a crude triacylglycerol. The CDTAG or ORTAG is contacted with an adsorbent packed into a column, or multiple columns in series, for a sufficient amount of time to remove impurities such as, but not limited to, soaps, metals, chlorophyll, and many of the other compounds that reduce the stability of the TAG. The resulting TAG exiting the column(s) is ready for the deodorization process. Once the adsorbent no longer removes the desired amount of impurities, it is regenerated for reuse. Such a continuous regenerable adsorbent refining process substantially reduces the amount of fresh water required and the amount of waste water generated to purify TAG and reduces the amount of solid waste produced.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/102,038, filed Oct. 2, 2008, the entirety of which is hereby incorporated by reference into this application. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to purification of edible oils and in particular, triacylglycerol, more particularly, to a process for continuous purification of edible oils using an adsorbent material contained in one or more columns and regeneration of the adsorbent material for re-use. 
     2. Description of the Related Art 
     Animal and vegetable fats and oils are an essential and popular component of a healthy diet. These oils and fats provide essential nutrients and energy while making many other essential components of a healthy diet more palatable. In 2008 alone, the world-wide consumption of vegetable oils alone was almost 140 million short tons. These oils and fats must be refined in order to remove undesirable impurities that accelerate spoilage and reduce palatability and stability. Impurities to be removed include free fatty acids (FFA), metals, chlorophyll, and phosphatides and gums along with other trace compounds that reduce shelf-life, performance and palatability in the finished oil of fat. 
     A conventional edible oil refinery uses vast amounts of fresh water to refine its products and produces a corresponding amount of effluent requiring wastewater treatment or disposal into rivers, lakes, or other bodies of water. Additionally, the refinery uses substantial quantities of filter aid or treating media which once used requires disposal by landfill. It is desirable to utilize a process that minimizes the use of fresh water and treating media in order to reduce processing costs, effluent and solid waste. 
     Oils and fats, which are comprised of triacylglycerols (TAG), must be refined in order to remove undesirable impurities. During the processing of vegetable TAGs, extraction of crude TAG from the oilseed typically involves the use of a non-polar solvent. The conventional solvent most widely used for this process is hexane. Crude TAG is highly soluble in hexane thus allowing for a highly effective extraction of crude TAG from the oilseed. The resulting mixture of crude TAG and hexane can be separated, typically by distillation. The hexane is then recycled for reuse in the solvent extraction process while the crude TAG is further processed and refined by either a “Chemical Refining Process” or a “Physical Refining Process” as described below. 
     Regardless of the choice of refining method, the TAG should be “degummed” prior to moving forward with the process. The degumming process involves the use of water to remove water soluble phosphatides (gums) from the TAG. The water portion is removed from the TAG by centrifugation. General steps involved for each refining method are described below. 
     Chemical Refining Process: 
     A conventional process of chemical refining begins with a crude degummed triacylglycerol (TAG). The crude degummed TAG is subjected to an alkaline solution (typically, sodium hydroxide) to neutralize free fatty acids (FFA) and form a corresponding soap molecule (e.g., sodium oleate). These soaps are removed from the TAG. Centrifugation is used to remove some of the soaps. However, some of the soaps formed during the neutralization are not readily removed by this step and the residual soaps can be removed by further processing. 
     Residual soaps are removed via different methods. In a first conventional method, water wash is used to remove residual soaps: Since residual soaps are soluble in water, a series of water washing steps can be utilized to remove residual soaps from the TAG. This involves the addition of water to the TAG and soap mixture followed by centrifugation to separate and remove the soap-stock. While this process is efficient for removing the majority of the soaps from the TAG, there are still residual soap molecules remaining in the TAG that must be removed. In addition, there are other impurities present that are not water soluble and thus are not removed using the water washing method. Therefore, further processing of the TAG is required. 
     In a second conventional method, silica gel treatment using filtration is used to remove soaps from the TAG. The silica gel treatment method has been developed as an attempt to minimize waste effluent streams from the process. A silica gel is added to the TAG to remove soaps and it also removes metals that may be present. This process is highly efficient, but is done in batches, requires filtration, and can produce large amounts of waste filter cake requiring disposal. 
     Regardless of which conventional chemical refining method is chosen, the next step in the process is a bleaching step. During the bleaching step, the TAG is contacted with a bleaching clay to remove chlorophyll and other impurities that cause stability problems in finished TAG. Bleaching clays are traditionally used for this process due to their efficacy for removing chlorophyll pigments and other trace impurities present in the TAG. Bleaching clays can also remove residual soaps that may not have been removed during the previous processing step. The use of bleaching clay is typically done in batches, requires filtration, and results in large amount of waste filter cake requiring disposal. 
     The final step in the conventional chemical refining process involves subjecting the refined and bleached TAG to a deodorizing process. The deodorizing process uses steam and vacuum to remove any residual FFA and other volatile impurities that cause odor and color problems in finished TAG. The resulting finished oil from the process is referred to as refined, bleached, deodorized (RBD) TAG. 
     Conventional chemical refining processes include many variations of the above described methods, such as combining of the silica gel and bleaching clay treatments in one filtration cycle. This allows for faster processing of the TAG. Another conventional process uses a combination of water washing and silica treatment to displace one or more of the water washing steps. Conventional chemical refining of TAGs has the shortcoming of using large amounts of water and generating large amounts of waste effluent and/or solid filter cake waste, depending on the process used. 
     Physical Refining Process: 
     The conventional process of physical refining begins with a crude degummed triacylglycerol (TAG). The crude degummed TAG is first subjected to a bleaching clay and/or a silica gel to remove phosphorus compounds and other metals, chlorophyll and other contaminants that cause stability problems in TAGs. The physical refining process generates large amounts of solid filter cake waste that require disposal. 
     After the bleaching step, the TAG is subjected to the use of steam to remove the majority of FFA present in the TAG. Depending on the condition of the TAG, this step may be performed in a similar fashion to the deodorization step described above in the chemical refining process. If the TAG has a high FFA content, the use of steam to strip the majority of the FFA may be performed prior to a final deodorization step. The final TAG is referred to as refined, bleached, deodorized (RBD) TAG. 
     Conventional physical refining processes include many variations of the above described process. Conventional physical refining of TAG has the shortcoming of using large amounts of solid filter media and generating large amounts of solid waste requiring disposal. 
     Typically, whether a chemical refining or physical refining process is chosen depends on the condition of the crude degummed triacylglycerol (CDTAG). CDTAG that contains a high amount of FFA (&gt;1.5%) is typically processed using physical refining. This is primarily because the risk of forming soap emulsion increases as the FFA content of a CDTAG increases. The more soap that is formed in the refining step, the greater the chance of emulsification, which results in increased processing difficulties and higher yield loss. 
     The following patents describe the use of an adsorbent to remove impurities from triacylglycerol compounds. U.S. Pat. No. 1,745,952 discloses a method for decolorizing fatty substances with adsorbents. U.S. Pat. No. 3,955,004 addresses a process for treating edible glyceride oil to improve color and storage properties using silica and aluminas. U.S. Pat. No. 2,401,339 describes a process to treat oils and waxes to remove impurities through the use of a solid adsorbent and distillation. U.S. Pat. No. 4,781,864 discloses a process for the removal of chlorophyll, color compounds and phospholipids using acid-treated silica type adsorbents. 
     U.S. Pat. No. 5,231,201, U.S. Pat. No. 5,248,799, U.S. Pat. No. 5,264,597, U.S. Pat. No. 5,928,639, U.S. Pat. No. 6,248,911, European Patent No. 0295418 B1, European Patent No. 0566224 A2, and U.K. Patent No. GB 2058121 A all relate to a process by which a refined glyceride oil is treated with an amorphous silica to remove impurities during chemical and/or physical refining. 
     U.K. Patent Application No. GB 2122588 A describes a process for regenerating spent adsorbents used for refining fatty materials, comprising contacting the spent adsorbent first with a polar organic solvent to remove adsorbed impurities and then with a non-polar organic displacing agent to remove the solvent adsorbed and reactivate the adsorbent. 
     None of aforementioned patents describe a complete system employing a continuous purification process using columns in combination with regeneration of the adsorbent. None of the prior art of which applicant is aware provides the feature of a continuous, regenerable adsorbent system that can be used to effectively and economically remove impurities when using chemical or physical refining methods. A purification system employing this feature is desirable in order to conserve and efficiently use scarce resources. Such a system dramatically reduces or eliminates the need for fresh water and the treatment or disposal or effluent and/or solid waste. 
     It is desirable to eliminate batch processing and provide a continuous process for the purification of edible oils. It is also desirable to provide an environmentally friendly “green” process that greatly reduces or eliminates the large volumes of fresh water conventionally required and waste water produced to refine edible oils and fats, as well as, the energy and space required to produce, transport, and landfill solid waste. It is further desirable to provide a process that once charged with an adsorbent comprises a closed system requiring no fresh water or new adsorbent for operation while generating no effluent or solid waste that needs to be treated or disposed of. 
     SUMMARY OF THE INVENTION 
     The continuous regenerable adsorbent process of the present invention is an environmentally friendly “green” refining process for the continuous purification of TAG using a powdered, granulated, or extruded adsorbent which can be used in conjunction with either chemical or physical refining processes. The adsorbent is contained in a column or suitable filtration system and is regenerated for reuse. The process substantially reduces the need for fresh water, treatment of waste effluent, and disposal of solid waste. 
     The process utilizes an adsorbent column system as a treatment rather than a conventional water wash step and/or batch filtration step to remove soaps and other impurities entrained in a crude degummed triacylglycerol (CDTAG) in a chemical and/or physical refining process. In the chemical refining process, the CDTAG is first refined to remove FFA, forming a once refined triacylglycerol (ORTAG), and then contacted with an adsorbent packed into column(s) prior to deodorization. In the physical refining process, the CDTAG is contacted with an adsorbent packed into column(s) prior to the removal of FFA and deodorization steps. 
     The CDTAG or ORTAG is contacted with a sufficient amount of adsorbent and for a sufficient amount of time to remove impurities, such as soaps, metals, chlorophyll, and many of the other impurities that reduce the stability of finished TAG. The life cycle of the adsorbent in the column(s) depends on the level of impurities in the incoming CDTAG or ORTAG, the quantity and adsorptive capacity of the adsorbent in the column(s), and the flow rate of the CDTAG or ORTAG through the column system. TAG so treated results in a product acceptable to proceed into a deodorization step without the need for water washing or batch adsorptive treatment with filtration. 
     Once the TAG exiting the column(s) no longer meets required parameters for the next step in the process, the adsorbent column(s) in the system are regenerated for reuse. This regeneration of the adsorbent makes the system of the present invention both economical and environmentally friendly. Regeneration and reuse of the adsorbent eliminates large amounts of waste water and/or solid filter cake waste produced in conventional chemical and physical refining processes. The regeneration of the adsorbent, as opposed to disposal of the adsorbent, reduces the production of solid waste. Reclamation by distillation of solvents used in the regeneration process of the present invention further enhances economics of the process and its environmental benefits. 
     There are several different embodiments that can be used to regenerate the adsorbent depending upon the process being utilized to refine and process the TAG. In a first embodiment which can be used with edible oil purification in either a chemical or physical refining process, the first step in the regeneration of the adsorbent involves reclaiming residual TAG absorbed by the adsorbent with a non-polar solvent (NPS), such as hexane, which is typically used in a solvent extraction process of crude TAG. The NPS is passed through the adsorbent column to strip the absorbed TAG, which is soluble in the NPS, from the adsorbent. 
     When the system of the present invention is used in an oil seed processing plant, specifically in the oil extraction process, the resulting NPS and TAG mixture exiting the adsorbent column can be added directly into the NPS and TAG from the TAG extraction step in the oil extraction process. The NPS from this first step of the adsorbent regeneration is reclaimed, typically by distillation, for reuse along with the NPS from the solvent extraction of the crude TAG from the oilseed. Alternatively, if there is no upstream TAG extraction step, the NPS and TAG mixture can be separated by distillation and the residual TAG can be sent downstream to the next step in the process for further processing, typically deodorization or FFA steam stripping, and the NPS can be reclaimed and reused in the regeneration process. If the resulting TAG from the separation process does not meet required parameters or specifications it can be sent back upstream to the adsorbent column(s) for reprocessing. 
     During a second step of the regeneration of the adsorbent, a polar solvent (PS), such as methanol or ethanol, is mixed with an acid, such as sulfuric acid, and is passed through the adsorbent column to remove the adsorbed impurities contained in and on the adsorbent. The PS and acid solution is passed through the column until such time as there are no significant quantities of impurities in the resulting PS and acid solution filtrate. The regenerated adsorbent is then ready to be reused in the purification process. The adsorbent can be reused multiple times until such time as it loses adsorptive capacity or is physically degraded to such an extent that it can no longer be used. 
     The mixture resulting from the second step of the regeneration process contains PS, acid, alkyl soaps, metals, chlorophyll and other impurities. The PS from the mixture of PS and acid and impurities can be reclaimed for reuse using distillation. The distillation process involves subjecting the mixture of PS and acid and impurities to heat and/or vacuum so that only the PS volatilizes and is then collected and reclaimed for reuse in the adsorbent regeneration process. The remaining residue not volatilized by the distillation process can be either disposed of or, preferably, further processed into a value added product. 
     In a second embodiment which can be used in a chemical refining process, the regeneration can be accomplished using a single solvent. A polar solvent (PS), such as methanol or ethanol, is mixed with an acid, such as sulfuric acid, and is passed through the adsorbent column to remove impurities contained in and on the adsorbent. The solution of PS and acid is passed through the adsorbent column until such time as there are no significant quantities of impurities in the resulting PS and acid solution filtrate. 
     The regenerated adsorbent is then ready to be reused in the purification process. The adsorbent can be reused multiple times until such time as it loses adsorptive capacity or is physically degraded to such an extent that it can no longer be used. 
     The mixture resulting from the regeneration process contains PS, acid, alkyl soaps, metals, chlorophyll, TAG, and other impurities which can be further processed to recover the residual TAG and PS. The PS can be reclaimed for reuse using distillation. 
     The distillation process involves subjecting the mixture of PS, acid and TAG impurities to heat and/or vacuum so that only the PS volatilizes and is then collected and reclaimed for reuse in the adsorbent regeneration process. The remaining residue not volatilized by the distillation process can be either disposed of or, preferably, further processed to recover the residual TAG. 
     To recover the residual TAG, the residue not volatilized by the distillation process which contains alkyl soaps, metals, chlorophyll, residual TAG and other impurities can be added back upstream into the process at the point at which the alkaline solution is added to the CDTAG. This CDTAG will then be centrifuged and the impurities from the regeneration process will be separated from the residual TAG. This recovered TAG is combined with the ORTAG after the centrifugation. The recovered TAG then becomes part of the ORTAG which is then further processed by passing through the adsorbent column(s) as described above. 
     In a third embodiment which can be used in a physical refining process, the regeneration can be accomplished using a single solvent. A polar solvent (PS), such as methanol or ethanol, is passed through the column to remove impurities contained in and on the adsorbent. The PS is passed through the adsorbent column until such time as there are no significant quantities of impurities in the resulting PS filtrate. 
     The regenerated adsorbent is then ready to be reused in the purification process. The adsorbent can be reused multiple times until such time as it loses adsorptive capacity or is physically degraded to such an extent that it can no longer be used. 
     The mixture resulting from the regeneration process contains PS, alkyl soaps, metals, chlorophyll, and residual TAG which can be further processed to recover the PS and possibly other constituents. The PS can be reclaimed for reuse using distillation. 
     The distillation process involves subjecting the mixture of PS, TAG and impurities to heat and/or vacuum so that only the PS volatilizes and is then collected and reclaimed for reuse in the adsorbent regeneration process. The remaining residue not volatilized by the distillation process can be further processed to yield value added products or disposed of. 
     Regardless of which method is chosen for the regeneration process, after the regeneration process, the adsorbent will still have some residual solvent remaining absorbed in it. The amount of solvent remaining in the column will depend on how well the column is dried after the regeneration process. Once the flow of crude TAG is restarted through the regenerated adsorbent column, residual solvent from the adsorbent will become entrained in the TAG first passing through the column. The TAG exiting the column with entrained solvent may be sent directly to the deodorization step in the refining process, a step that will strip the solvent from the TAG. Alternatively, the TAG exiting the column with entrained solvent may be sent to a separate evaporation step to strip the solvent from the TAG prior to being sent to the deodorization step in the refining process. 
     The invention will be more fully described by reference to the following drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is schematic diagram of a system for purification of animal and vegetable oils using an adsorbent column purification method in a chemical refining application in accordance with the teachings of the present invention. 
         FIG. 2  is a schematic diagram of an alternative embodiment of the system for purification of animal and vegetable oils in a chemical refining application using multiple adsorbent columns is accordance with the teachings of the present invention. 
         FIG. 3  is a schematic diagram of a system for purification of animal and vegetable oils using an adsorbent column purification method in a physical refining application in accordance with the teachings of the present invention. 
         FIG. 4  is a schematic diagram of an alternative embodiment of the system for purification of animal and vegetable oils in a physical refining process using multiple adsorbent columns in accordance with the teachings of the present invention. 
         FIG. 5  is a schematic diagram of dual solvent regeneration of adsorbent in both chemical and physical refining processes with non-polar solvent and polar solvent with acid. 
         FIG. 6  is a schematic diagram of single solvent regeneration of adsorbent in a chemical refining process using a polar solvent with acid. 
         FIG. 7  is a schematic diagram of single solvent regeneration of adsorbent in a physical refining process using a polar solvent. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in greater detail to a preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts. 
       FIG. 1  is a schematic diagram of continuous edible oil purification by adsorbent system  10  in accordance with the teachings of the present invention. In a first embodiment, single adsorbent column  12  packed with adsorbent material  14  is used to purify once refined triacylglycerol (ORTAG) from a chemical refining process  16 . ORTAG  16  is contacted with a sufficient amount of adsorbent material  14  and for a sufficient amount of time to remove impurities, such as soaps, chlorophyll, metals, phosphorous, phosphatides, gums, free fatty acids (FFA), flavor compounds, odor compounds, and color compounds and other impurities that reduce the stability of finished TAG. Suitable adsorbent materials  14  include carbon, silica, zeolite, metal silicate, metal oxide, silica gel, activated alumina, bleaching clay and activated bleaching clay. Adsorbent material  14  can be a powder, granulated or extruded or otherwise processed to facilitate flow through adsorbent column  12 . In preferred embodiments, adsorbent material  14  is magnesium silicate, synthetic magnesium silicate, silica gel, activated alumina, bleaching clay or activated bleaching clay. 
     Purified TAG  17  exiting adsorbent column  12  is suitable to proceed to deodorization process  18  without the need for water washing or a batch adsorptive filtration treatment. Deodorization process  18  can use steam and vacuum to remove any residual FFA and other volatile impurities. Refined, bleached, deodorized (RBD) TAG  19  results from deodorization process  18 . 
     In this embodiment of a chemical refining process, crude degummed TAG (CDTAG)  20  is refined using caustic refining step  22 . In caustic refining step  22 , CDTAG  20  is subjected to an alkaline solution, for example a solution of sodium hydroxide, for neutralizing free fatty acids and forming a corresponding soap molecule. Separation of soapstock step  26  results in soapstock  28  being removed to provide ORTAG  16 . Separation of soapstock step  26  can be performed with centrifugation to remove soapstock  28 . 
     During the column adsorption purification step, ORTAG  16  flows through adsorbent column  12  until such time as adsorbent material  14  no longer removes sufficient impurities from ORTAG  16 . This is determined by comparing the level of impurities in ORTAG  16  entering adsorbent column  12  to those in purified TAG  17  exiting adsorbent column  12 . At such time as purified TAG  17  exiting adsorbent column  12  no longer meets the required specification or desired parameters, a regeneration of adsorbent material  14  is performed as described below. 
     In a second embodiment of continuous edible oil purification by adsorbent system  100 , a plurality of adsorbent columns  12   a - 12   b  packed with adsorbent material  14  are used in series to purify ORTAG from the chemical refining process  16 , as shown in  FIG. 2 . The use of multiple adsorbent columns allows for a continuous process. After the chemical refining process and separation of soapstock step  26 , ORTAG  16  is contacted with adsorbent material  14  in lead adsorbent column  12   a . Purified TAG  17   a  exiting adsorbent column  12   a  is contacted with adsorbent material  14  in lag adsorbent column  12   b  packed with adsorbent material  14  to remove impurities remaining in purified TAG  17   a.    
     ORTAG  16  and purified TAG  17   a  are contacted with a sufficient amount of adsorbent material  14  and for a sufficient amount of time to remove impurities, such as soaps, chlorophyll, metals, and many of the impurities that reduce the stability of finished TAG. ORTAG so treated will result in refined and purified TAG without the need for water washing or batch adsorptive filtration treatment, prior to deodorization process  18 . 
     During the column adsorption purification step, ORTAG  16  and purified TAG  17   a  flows through the columns until such time as adsorbent material  14  no longer removes sufficient impurities. This is determined by comparing the level of impurities in ORTAG  16  and/or purified TAG  17   a  entering both lead adsorbent column  12   a  and lag adsorbent column(s)  12   b  to those in the purified TAG  17   a  and purified TAG  17   b  exiting respective lead adsorbent column  12   a  and lag adsorbent column  12   b . At such time as the purified TAG  17  exiting adsorbent columns  12  no longer meets the required specifications or desired parameters for the next step in the process as determined appropriate for each column, a regeneration of the lead column is performed as described below. 
     In a third embodiment of continuous edible oil purification for a physical refining process by adsorbent system  200 , a single adsorbent column  12  packed with adsorbent material  14  is used to purify crude degummed triacylglycerol (CDTAG)  20 , as shown in  FIG. 3 . After the crude TAG is degummed and centrifuged to separate the water soluble gums, such as phosphatides, CDTAG  20  is contacted with a sufficient amount of adsorbent material  14  and for a sufficient amount of time to remove impurities, such as soaps, chlorophyll, metals, and many other impurities that reduce the stability of purified TAG. A CDTAG so treated will result in processed TAG without the need for additional batch adsorptive treatment with filtration. At this point, purified TAG  17  is ready for the steam stripping process  50  to remove the majority of the FFA which is then further processed by deodorization process  18  to provide refined, bleached, deodorized (RBD) TAG  19 . 
     During the column adsorption purification step, CDTAG  20  flows through adsorbent column  12  until such time as adsorbent material  14  no longer removes sufficient impurities from CDTAG  20 . This is determined by comparing the level of impurities in CDTAG  20  entering adsorbent column  12  to those in purified TAG  17  exiting adsorbent column  12 . At such time as the purified TAG  17  exiting adsorbent column  12  no longer meets the required specification or desired parameters for the next step in the process, a regeneration of adsorbent material  14  is performed. When regeneration is performed, the use of a second column may be employed for the purification process while the first column is being regenerated as described above. This allows for a continuous process. 
     In a fourth embodiment, a plurality of adsorbent columns  12   a - 12   b  packed with adsorbent material  14  are used in series to purify a crude degummed triacylglycerol (CDTAG)  20  for a physical refining process, as shown in  FIG. 4 . The use of multiple columns allows for a continuous process. After the crude TAG is degummed and centrifuged to separate the water soluble gums, such as phosphatides, CDTAG  20  is contacted with adsorbent material  14  in lead adsorbent column  12   a  and lag adsorbent column(s)  14   b  packed with adsorbent material  14  to intercept impurities from CDTAG  20 . 
     CDTAG  20  is contacted with a sufficient amount of adsorbent and for a sufficient amount of time to remove impurities, such as soaps, chlorophyll, metals, and impurities that reduce the stability of finished TAG. CDTAG so treated will result in processed TAG without the need for additional batch adsorptive treatment with filtration. At this point, purified TAG  17   b  is ready for the steam stripping process  50  to remove the majority of the FFA which is then further processed by deodorization process  18 . 
     During the column adsorption purification step, CDTAG  20  flows through column  12   a  and column(s)  12   b  until such time as the adsorbent no longer removes sufficient impurities from CDTAG  20 . This is determined by comparing the level of impurities in CDTAG  20  and/or purified TAG  17   a  entering both lead adsorption column  12   a  and lag adsorbent column(s)  12   b  to those in purified TAG  17   a  and purified TAG  17   b  exiting the columns. At such time as the purified TAG  17  exiting the columns  12  no longer meets the required specifications or desired parameters for the next step in the process as determined appropriate for each column, regeneration of the lead column is performed as described below. 
     During regeneration in a chemical refining processes or physical refining processes shown in  FIGS. 1-4 , feed to adsorbent column  12  to be regenerated is stopped from adsorbent column  12  and adsorbent material  14  within adsorbent column  12  is regenerated. Non-polar solvent (NPS)  34  from non-polar solvent tank  33  is passed through adsorbent column  12  to be regenerated, as shown in  FIG. 5 . One suitable NPS  34  is hexane. NPS  34  is passed through adsorbent column  12  to strip absorbed TAG which is soluble in NPS  34  from adsorbent material  14 . NPS and TAG mixture  35  exiting adsorption column  12  can be optionally sent to a NPS and TAG extraction step  36 . Decision module  401  determines if the process includes a solvent extraction step. If the process includes an solvent extraction step, NPS and TAG mixture  35  is added upstream to the solvent extraction step (which is prior to step  20  as shown in  FIG. 1-4 ). If the process does not include an extraction step, NPS and TAG mixture  35  is forwarded to NPS distillation  37  for reclamation of reclaimed TAG  38  and reclaimed NPS  39 . Decision module  402 , determines if reclaimed TAG  38  meets required parameters or specifications. If reclaimed TAG  38  meets required parameter or specifications, reclaimed TAG  38  can be forwarded to deodorization process  18 . If reclaimed TAG  38  does not meet required parameters or specifications, reclaimed TAG  38  can be sent to adsorbent column  12  for reprocessing. Reclaimed NPS  39  can be reused by adding reclaimed NPS  39  to non-polar solvent tank  33 . 
     During a second step of the regeneration of adsorbent material  14 , polar solvent  40  is mixed with acid  41  in polar solvent and acid tank  42 . A suitable polar solvent is an alcohol, such as methanol or ethanol. A suitable acid is sulfuric acid. Polar solvent and acid mixture  43  is passed through adsorption column  12  to remove adsorbed impurities contained in and on adsorbent material  14 . Polar solvent and acid mixture  43  is passed through adsorption column  12  until such time as mixture  45  exiting adsorption column  12  contains an impurity level of zero, indicating that most if not all impurities have been stripped from the adsorbent  14  with the polar solvent solution. Mixture  45  contains the polar solvent, acid, alkyl soaps, metals, chlorophyll and other impurities. Polar solvent distillation  46  can be used for reclaiming reclaimed polar solvent  47  from soap and other impurities  48 . Polar solvent distillation  46  can subject mixture  45  to heat and/or vacuum to provide reclaimed polar solvent  47 . Reclaimed polar solvent  47  can be reused by adding reclaimed polar solvent  47  to polar solvent and acid tank  42 . 
     During regeneration of a multiple column system, as shown in  FIGS. 2 and 4 , the first lag column  12   b  in the series becomes the new lead column and any subsequent lag column(s) are moved up in the order of contact in the column treatment process. Adsorbent material  14  in the original lead column is regenerated for reuse and becomes the new last lag column in the system. 
     In an alternate embodiment, a single solvent regeneration can be used in a chemical refining process as shown in  FIGS. 1-2 . As shown in  FIG. 6 , feed to adsorbent column  12  to be regenerated is stopped from adsorbent column  12  and adsorbent material  14  within adsorbent column  12  is regenerated. Polar solvent  40  is mixed with acid  41  in polar solvent and acid tank  42 . A suitable polar solvent is an alcohol, such as methanol or ethanol. A suitable acid is sulfuric acid. Polar solvent and acid mixture  43  is passed through adsorption column  12  to remove adsorbed impurities contained in and on adsorbent material  14 . Polar solvent and acid mixture  43  is passed through adsorption column  12  until such time as mixture  45  exiting adsorption column  12  contains an impurity level of zero, indicating that most if not all impurities have been stripped from the adsorbent with the polar solvent solution. Mixture  60  contains the polar solvent, acid, alkyl soaps, residual TAG and other impurities. Polar solvent distillation  62  can be used for reclaiming reclaimed polar solvent  67 . Polar solvent distillation  62  can subject mixture  60  to heat and/or vacuum to provide reclaimed polar solvent  67 . Reclaimed polar solvent  67  can be reused by adding reclaimed polar solvent  67  to polar solvent and acid tank  42 . Residual TAG and other impurities  64  can be added back upstream into the process at the point at which the alkaline solution is added to the CDTAG in step  22 , as shown in  FIGS. 1 and 2 . 
     In an alternate embodiment, a single solvent regeneration of adsorbent can be used in a physical refining process, as shown in  FIGS. 3-4 . Polar solvent  40  is passed through adsorption column  12  to remove adsorbed impurities contained in and on adsorbent material  14 , as shown in  FIG. 7 . Polar solvent  40  is passed through adsorption column  12  until such time as mixture  70  exiting adsorption column  12  contains an impurity level of zero, indicating that most if not all impurities have been stripped from adsorbent material  14  with polar solvent solution filtrate. Mixture  70  contains the polar solvent, soaps, residual TAG and other impurities. Polar solvent distillation  72  can be used for reclaiming reclaimed polar solvent  77 . Polar solvent distillation  72  can subject mixture  70  to heat and/or vacuum to provide reclaimed polar solvent  77 . Reclaimed polar solvent  77  can be reused by adding reclaimed polar solvent  77  to polar solvent  40 . In step  74 , remaining residue  73  not volatilized by distillation process  72  can be further processed or disposed of. Remaining residue  73  can include the residual TAG, soaps or other impurities. 
     The invention can be further illustrated by the following examples thereof, although it will be understood that these examples are included merely for purposes of illustration and are not intended to limit the scope of the invention unless otherwise specifically indicated. All percentages, ratios, and parts herein, in the Specification, Examples, and Claims, are by weight and are approximations unless otherwise stated. 
     Example 1 
     Dual Column Purification Using Synthetic Magnesium Silicate 
     ORTAG was passed through a two column system, as shown in  FIG. 2  in series containing 2 g synthetic magnesium silicate (D-SOL D60 from The Dallas Group of America, Whitehouse, N.J.). Two different flow rates were tested using the same adsorbent with the same ORTAG feedstock. A summary of the results obtained from this test is shown in Table 1. The ORTAG was passed through the column until such time that the soap content of the ORTAG exiting the column was greater than 5 ppm. The initial soap concentration of the ORTAG was between 80-130 ppm. 
     Additionally, various samples were analyzed for chlorophyll a. These results are shown in Table 2. The initial ORTAG contained approximately 1.8 ppm Chlorophyll a. 
     At such time that the TAG exiting the column contained more than 5 ppm soap, the column treatment was stopped and the synthetic magnesium silicate in the lead column was regenerated, as shown in  FIG. 5 . A solution of hexane was first passed through the column to remove any residual TAG remaining in and on the column. After this was completed, a solution containing 0.10% sulfuric acid (93%) in ethanol was passed through the column until such time that the ethanol/sulfuric acid mixture exiting the column contained a soap value of zero. 
     After the regeneration of the product, the lag column became the new lead column and the regenerated lead column was placed back in series as the new lag column. Thereafter, ORTAG was passed through the column system. 
     
       
         
               
             
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Summary of Column Purification Using Synthetic Magnesium Silicate 
               
               
                 Synthetic Magnesium Silicate 
               
             
          
           
               
                 Two Columns in Series 
                 Flow Rate = 0.35 mL/min 
                 Flow Rate = 0.70 mL/min 
               
             
          
           
               
                 Total Column Loading 
                 Column Throughput (mL) 
                 % Treatment 
                 Column Throughput (mL) 
                 % Treatment 
               
             
          
           
               
                 4 g 
                 per Cycle 
                 Cumulative 
                 Cumulative 
                 per Cycle 
                 Cumulative 
                 Cumulative 
               
               
                   
               
             
          
           
               
                 Initial 
                 4101 
                 4101 
                 0.108% 
                 7402 
                 7402 
                 0.060% 
               
               
                 After 1st Regen. 
                 5513 
                 9614 
                 0.046% 
                 4803 
                 12205 
                 0.036% 
               
               
                 After 2nd Regen. 
                 6733 
                 16347 
                 0.027% 
                 1265 
                 13470 
                 0.033% 
               
               
                 After 3rd Regen. 
                 3590 
                 19937 
                 0.022% 
                 1600 
                 15070 
                 0.029% 
               
             
          
           
               
                 AVERAGE mL 
                 4984 
                 3768 
               
               
                 TOTAL mL 
                 19937 
                 15070 
               
               
                 TOTAL g 
                 17943 
                 13563 
               
               
                 % Treatment 
                 0.022% 
                 0.029% 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Results for Chlorophyll Removal using 
               
               
                 Synthetic Magnesium Silicate 
               
             
          
           
               
                 Sample # 
                 Amount through column(ml) 
                 Chlorophyll a (ppm) 
               
               
                   
               
             
          
           
               
                 Initial Cycle 
               
             
          
           
               
                 1 
                 100 
                 0.534 
               
               
                 11 
                 1171 
                 1.480 
               
               
                 21 
                 2221 
                 1.560 
               
               
                 31 
                 3191 
                 1.463 
               
               
                 41 
                 4196 
                 1.518 
               
             
          
           
               
                 After 1st Regeneration 
               
             
          
           
               
                 1 
                 110 
                 0.372 
               
               
                 12 
                 1260 
                 1.535 
               
               
                 22 
                 2270 
                 1.547 
               
               
                 32 
                 3315 
                 1.555 
               
               
                 42 
                 4340 
                 1.582 
               
               
                 52 
                 5418 
                 1.545 
               
             
          
           
               
                 After 2nd Regeneration 
               
             
          
           
               
                 1 
                 110 
                 0.763 
               
               
                 51 
                 5268 
                 0.579 
               
               
                 61 
                 6333 
                 0.604 
               
               
                 70 
                 7273 
                 0.570 
               
             
          
           
               
                 After 3rd Regeneration 
               
             
          
           
               
                 1 
                 95 
                 0.266 
               
               
                 10 
                 1040 
                 0.613 
               
               
                 20 
                 2045 
                 0.594 
               
               
                 30 
                 3070 
                 0.587 
               
               
                 40 
                 4090 
                 0.578 
               
               
                   
               
             
          
         
       
     
     Example 2 
     Single Column Purification Using Silica Gel 
     ORTAG was passed through a single column, as shown in  FIG. 1  containing 2 g Silica Gel 60 (EMD Chemicals) at a flow rate of 0.35 mL/min. A summary of the results obtained from this product is shown in Table 3. The ORTAG was passed through the column until such time that the soap content of the ORTAG exiting the column was greater than 5 ppm. The initial soap concentration of the ORTAG was between 80-130 ppm. 
     Additionally, various samples were analyzed for chlorophyll a. These results are shown in Table 4. The initial ORTAG contained approximately 1.8 ppm Chlorophyll a. 
     
       
         
               
             
               
               
               
             
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 Summary for Single Column Purification Using Silica Gel 60 
               
             
          
           
               
                   
                 SINGLE COLUMN 
                 Silica Gel 60 
               
               
                   
                 Column Loading 
                 Column Throughput (mL) 
               
               
                   
                 2 g 
                 per Cycle 
               
               
                   
                   
               
             
          
           
               
                   
                 TOTAL mL 
                 1151 
               
               
                   
                 TOTAL g 
                 1036 
               
               
                   
                 % Treatment 
                 0.193% 
               
               
                   
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
             
               
               
               
             
           
               
                 TABLE 4 
               
             
             
               
                   
               
               
                 Summary of Column Purification Using Silica Gel 60 
               
             
          
           
               
                   
                 Initial Cycle 
                   
               
               
                 Sample # 
                 Amount through column(ml) 
                 Chlorophyll a (ppm) 
               
               
                   
               
             
          
           
               
                 1 
                 120 
                 0.230 
               
               
                 11 
                 1276 
                 0.535 
               
               
                   
               
             
          
         
       
     
     It is to be understood that the above described embodiments are illustrative of only a few of many possible options for regeneration which represent applications of the principles of the invention. Numerous and varied other arrangements can be readily devised in accordance with these principles by those skilled in the art without departing from the spirit and scope of the invention.