EP0915734A1 - Procede enzymatique d'elimination des contaminants d'une resine d'echange d'ions et de fractionnement - Google Patents

Procede enzymatique d'elimination des contaminants d'une resine d'echange d'ions et de fractionnement

Info

Publication number
EP0915734A1
EP0915734A1 EP97936972A EP97936972A EP0915734A1 EP 0915734 A1 EP0915734 A1 EP 0915734A1 EP 97936972 A EP97936972 A EP 97936972A EP 97936972 A EP97936972 A EP 97936972A EP 0915734 A1 EP0915734 A1 EP 0915734A1
Authority
EP
European Patent Office
Prior art keywords
resin
enzymes
enzyme
treatment
optimum
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP97936972A
Other languages
German (de)
English (en)
Inventor
John Slade
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Novozymes North America Inc
Novo Nordisk Biochem Inc
Original Assignee
Novo Nordisk Biochem North America Inc
Novo Nordisk Biochem Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Novo Nordisk Biochem North America Inc, Novo Nordisk Biochem Inc filed Critical Novo Nordisk Biochem North America Inc
Publication of EP0915734A1 publication Critical patent/EP0915734A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J49/00—Regeneration or reactivation of ion-exchangers; Apparatus therefor
    • B01J49/50—Regeneration or reactivation of ion-exchangers; Apparatus therefor characterised by the regeneration reagents
    • B01J49/57—Regeneration or reactivation of ion-exchangers; Apparatus therefor characterised by the regeneration reagents for anionic exchangers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J49/00—Regeneration or reactivation of ion-exchangers; Apparatus therefor
    • B01J49/50—Regeneration or reactivation of ion-exchangers; Apparatus therefor characterised by the regeneration reagents
    • B01J49/53—Regeneration or reactivation of ion-exchangers; Apparatus therefor characterised by the regeneration reagents for cationic exchangers

Definitions

  • the present invention is directed to the broad field of enzyme process technology. More specifically the present invention is directed to a method for removing contaminants from resins, particularly ion exchange and fractionation resins by use of enzyme treatment. The present invention also is directed to a method of producing purified corn sweeteners, particularly corn syrup and high fructose corn syrup by use of resins previously cleaned with enzymes.
  • Resins provide a powerful tool in analytical chemistry for separation of organic or inorganic ionic or nonionic species.
  • the resins are typically contained within a column or vessel.
  • Resins are manufactured from substances such as cross linked polystyrene, which have been chemically cross linked together, also known as DVB (di-vinyl benzene), in both macroporous (large holed) and gel (small holed) forms. Additional resins used in food processing are formed from acrylates. Resins can typically be reused by regenerating the resin. Deactivation or fouling of the resin by contaminants can destroy the resin. In addition to thermal instability (desulfonation or loss of functionalization) ionic, particulate (sludge) and polymeric materials cause fouling.
  • An ion exchange resin is a synthetic organic polymer, often based on cross- linked polystyrene, that has been derivatized by the addition of charged groups to produce materials that will exchange counterions when suspended in aqueous solutions.
  • Cationic exchange resins have fixed acidic substituents based on, for example, sulfonic acid which is a strong acid exchanger or carboxylic acid which is a weak acid exchanger.
  • Anionic exchange resins have fixed substituents based on for example, quaternary ammonium or ethoxyamine groups or amines which are weak base exchangers. Other functional groups may be attached to the resin skeletin to provide more selective behavior.
  • the degree of derivatization and the extent of cross-linking of the resin determines the overall capacity for ion exchange.
  • a technique called chromatography is used to separate mixtures of substances based on their ability to partition between a liquid and solid phase.
  • Ion-exchange chromatography is defined as a type of chromatography in which a solid support is an ion- exchange material used to separate mixtures of charged molecules or ions. This can be carried out on a preparative scale or as a modifcation of High Pressure Liquid Chromatography.
  • Chromatographic separations depend on differences in exchange potential, elution agent, column length and loading, flow rate particle size and temperature. Chromatographic separations can be used for a wide variety of uses including the purifcation of corn sweeteners such as corn syrup (CSU) and High fructose corn syrup (HFCS). Corn sweeteners are manufactured by hydrolyzing corn starch. A dextrose equivalent (D.E.) number is given to the finished ingredient depending on the degree of conversion allowed in the reaction. The lower the number, the lower the degree of conversion. Higher numbers indicate more complete conversion with 92 D.E. indicating complete conversion from corn starch to dextrose (Corn Sugar). High fructose corn syrup can be enzyme converted to 97 D.E.
  • CSU corn syrup
  • HFCS High fructose corn syrup
  • Corn sweeteners have been used in ice-cream and yogurt fruit preparations for years. Two reasons dominate the list of reasons for corn sweetener incorporation. First, corn sweeteners can give desirable body or "chewiness" to finished products that sucrose alone can't provide. Second, certain corn sweeteners impart more sweetness per pound than sucrose so they are less expensive to use. Obviously, because of the great value of corn sweeteners an improved method to regenerate resins which can be used to prepare purified corn sweeteners would be of great benefit. Currently, Ion Exchange and fractionation chromatography are the methods of choice in purifying corn sweeteners, however, the columns or vessels which contain the resin frequently become contaminated and are difficult to clean.
  • the current method of choice used for regeneration of resins involves the use of chemicals.
  • the chemicals typically used include but not limited to: hydrochloric acid (HC1), sodium hydroxide (NaOH), ammonium hydroxide (NH 4 OH) and sodium carbomate (Na 2 CO 3 ).
  • HC1 hydrochloric acid
  • NaOH sodium hydroxide
  • NH 4 OH ammonium hydroxide
  • Na 2 CO 3 sodium carbomate
  • the present invention is especially well-suited for cleaning ion exchange and fractionation resins used to purify corn sweeteners.
  • the present invention relates to an enzymatic method used to clean resins, particularly ion exchange and fractionation resins.
  • the method can be used alone or in combination with chemical methods.
  • the method allows for improved production of liquids that contain contaminants as for example proteins, carbohydrates, lipids, and residual unconverted starches that require fractionation or ion exchange treatment.
  • the invention also relates to a the use of resins for the production of corn sweeteners, in particular, corn syrup and high fructose corn syrup.
  • the present invention is directed to an enzymatic method of removing contaminants from resins, in particular ion-exchange and fractionation resins.
  • the enzymes are exposed to the contaminated resin and optionally recirculated through the resin for a particular time designated.
  • the amount of time the enzyme is recirculated is a production factor. The shorter the time allotted for treatment of the resin the larger the enzyme dose necessary to clean the resin.
  • the present invention can incorporate the novel use of enzymes in combination with traditional chemical treatment means to remove contaminants from resins.
  • Enzymes have a characteristic optimum pH at which their activity is maximal.
  • the pH-activity profiles of enzymes reflect the pH at which important proton-donating or proton-accepting groups in the enzyme catalytic site are in their required state of ionization.
  • the optimum pH of an enzyme is not necessarily identical with the pH of the normal surroundings, which may be just above or below the optimum pH.
  • the present invention can be served with exhisting proteases, lipases, carbohydrases and alpha amylases which operate at a p.H. of 1-9, more preferably between
  • Beta Glucanase (Finizym, Cereflo)
  • Lipase (Palatase, Lipozyme) Alpha Amylase (BAN, Termamyl Type L)
  • Multi-enzyme complexes include but are limited to: Alpha Amylase, Beta Glucanase, Protease (Ceremix) Carbohydrases (Viscozyme)
  • Protease/ Peptidase is defined as a class of enzymes which hydrolyze (breakdown) proteins into short chains, soluble peptides and amino acids.
  • Beta Glucanase is defined as a class of enzymes which hydrolyze beta glucans
  • the 1 ,4-beta and 1,3-beta designations refer to the chemical bonding between the carbon atoms in the molecule upon which the class of enzymes act upon.
  • Oligosaccharides are defined as short chains of dextrose molecules chemically bonded together. These chains are typically 3-5 glucose units in length.
  • Disaccharides are defined as two dextrose units linked together. These are only formed in minor amounts with beta glucanases.
  • Lipases are defined as a class of enzymes which hydrolyze both short and long chain fatty acids, from the 1,3-ester chemical bonding sites, into mono-or diglycerides and fatty acids.
  • Short chain triglycerides refer to triglycerides with sidechains with twelve carbon molecules or less, i.e. esters of lauric acid and below.
  • Long chain fatty acids refer to fatty acids with more than twelve carbon molecules i.e. esters above lauric acid.
  • Alpha amylases are defined as a class of enzymes which act at random to hydrolyze the alpha- l,4glucosidic lingages in amylose and amylopectin, resulting in the formation of soluble dextrins and oligosaccharides.
  • Alpha- 1 ,4-glucosidic linkage refers to the chemical bonding between the glucose molecules which compose starch. The number 1 carbon in one glucose molecule is bonded to the number 4 carbon of the adjoining carbon.
  • Amylose is strictly composed of alpha- 1 ,4-glucosidic linkages and is decomposed by alpha amylase.
  • Amylopectin is the second type of starch and is composed of both alpha- 1,4-glucosidic, and alpha- 1 ,6-glucosidic bonds.
  • Alpha amylases cannot break down 1,6 bonding, so amylopectin is more difficult to hydrolyze by alpha amylase.
  • Carbohydrase is defined as a broad class of enzymes which hydrolyze non- starch polysaccharides (beta- l ,4-alpha-l,4-alpha- 1,5). This class of enzymes includes: arabanasc, cellulase, beta-glucanase, hemi-cellulase, and xylanase.
  • Arabanase hydrolyzes arabans into oligoarabans and arabanose.
  • Cellulase hydrolyzes cellulose into oligocelluloses and cellubiose.
  • Hemi-cellulase hydrolyzes hemi-cellulose into oligopentosans and pentosans.
  • Xylanase hydrolyzes xylans into oligoxylans and xylose.
  • the optimum pH and temperature of each enzyme to be used is checked and, if possible, the enzymes are added in combination as a multienzyme complex.
  • the two enzymes are used in combination it is rare that both enzymes are used at their optimum pH and temperature. In this case a "common" overlap area where both enzymes have a relatively high activity is used. If the pH and temperature optimum of the two or more enzymes vary greatly then they are added successively. Typically, the two or more enzymes will be used in approximately the same ratio as the contaminant or contaminants.
  • multienzyme complexes include but are not limited to: Carbohydrases, including arabanase, cellulase, beta-glucanase, hemi- cellulase, and xylanase (Viscozyme) Alpha Amylases, Beta Glucanases, Proteases (Ceremix)
  • the contaminant is identified prior to enzymatic treatment.
  • this step is not an absolute requirement for cleaning to occur it will save money, time, and eliminate the use of ineffective enzymes and unsuccessful cleanings.
  • enzymes typically have a high degree of specificity for their substrates, ideally, the selection of the enzyme or enzyme mixture that is used to treat the resin is conducted after the contaminant or contaminants are identified.
  • the selection of enzymes must sometimes be conducted without knowledge of contaminants.
  • the resin prior to the treatment of the one or more enzymes the resin is pH adjusted to reside within the optimum pH range of the chosen enzyme(s). If a cation resin is to be treated, then the resin capacity should be completely exhausted using either NaOH or Na-,CO 3 until the pH reaches a level of 6-8, optimally 6.5-7.5. If is used to exhaust the resin care must be taken as CO 2 will form in the unit, increasing the overall pressure in the vessel.
  • a weak or strong base anion resin is ready to be treated after sweetening off. If the pH in the vessel is greater than 7.5, HCl should be used to complete the exhaustion of the resin.
  • the resin is thoroughly rinsed with a washing agent, as for example water, prior to tratment with one or more enzymes to remove an initial concentration of contaminant still undergoing a reaction, as for example undergoing ion-exchange.
  • a washing agent as for example water
  • sweetening off is defined as the rinsing of syrups, sugars, liquors, or other carbohydrate based liquids from the resin and vessel prior to chemical and/or enzymatic treatment, until the total amount of organic carbon in the vessel or unit is below 3500 parts per million (ppm), more preferably 2500 ppm.
  • Residual syrup is defined as syrup which remains in a vessel after 'sweetening off” has occurred.
  • Initial concentration of contaminant is defined as a level of contaminant greater than 2500 ppm, more preferably 1000 ppm and still more preferably 100 ppm.
  • Residual level of contaminant is defined as a level of contaminant less than 2500 ppm, more preferably 1000 ppm, and still more preferably 100 ppm.
  • the washing agent i.e. water
  • the washing agent i.e. water
  • salt can be added to the water to aid in the
  • the water should be softened or, if available, condensate water recovered from evaporators should be used. In carbon and corn wet milling industries, condensate water is the water of choice.
  • TOC total organic carbon
  • the rinsing agent also allows one skilled in the art to adjust the temperature of the resin before the treatment of the contaminant with one or more enzymes.
  • the temperature of the rinsing agent used should be within or slightly greater than the chosen enzyme(s) optimum range for temperature since the pH adjustment will reduce the temperature in the vessel.
  • the enzyme solution is rinsed with a solution, typically water, until the enzyme concentration in the vessel is exhausted.
  • the resin is regenerated using well-known chemical procedures. Typical concentration and chemicals used for regeneration include: For a weak base anion type resin 4% NaOH solution at 96-1 12 kg/m 3 and 5% Na-,CO 3 solution at 112-1 18 kg/m 3 is recirculated for 30-60 minutes at 40 C. For a strong base anion resin, 4% NaOH solution at 112-120 kg/m 3 and 7% Na 2 CO 3 solution at 80-96 kg/m3 is recirculated for 30-60 minutes at 40 C.
  • concentration and chemicals used for regeneration include: For a weak base anion type resin 4% NaOH solution at 96-1 12 kg/m 3 and 5% Na-,CO 3 solution at 112-1 18 kg/m 3 is recirculated for 30-60 minutes at 40 C. For a strong base anion resin, 4% NaOH solution at 112-120 kg/m 3 and 7% Na 2 CO 3 solution at 80-96 kg/m3 is recirculated for 30-60 minutes at 40 C.
  • Analysis for protein can be accomplished using the Kjeldahl method from Standard Analytical Methods of the members of the Corn Refiners Association. Inc. ; Corn
  • Beta-glucan (corn fiber) can be accomplished using the Crude Fiber method from Standard Analytical Methods of the Members of the Corn Refiners Association. Inc. ; Feedstuffs, Method G-12. There are other variations of this procedure but this method is the most applicable
  • Beta-glucan can be accomplished using the Crude Fiber method from Standard Analytical Methods of the . Members of the_ Corn Refiners Association, Inc. ; Feedstuffs, Method G-12. There are other variations of this procedure but this method is the most applicable Analysis for beta-glucan (corn fiber) can be accomplished using the Crude
  • the contaminant or contaminant is identified by the method of Example 1. Although this is not a requirement it allows for the appropriate choice of an enzyme or enzymes for treatment as well as proper selection of chemical treatment for the contaminant.
  • the total amount of contamination is estimated by and is expressed as a percentage of the total weight of resin plus contaminant.
  • the resin is rinsed (Sweetened off) in the ion exchange vessel with a rinsing agent, as for example water, until the residual contaminant or contaminant concentration (substance undergoing ion exchange), as for example corn syrup or high fructose corn syrup is brought down to an acceptable level, typically, 1000-2500ppm total organic carbon. Although lower levels are even more desirable.
  • the pH of the resin is adjusted to reside within the pH range of the chosen enzyme or enzymes.
  • the pH range is 5-9 , more preferably pH 5.5-7.5 and and temperature range is 20-75 C, more preferably 40-60 C.
  • a botanical protease is chosen such as Papain a pH range is between 2.5-10 more preferably 3-9.5 and a temperature range is between 30-60 C, more preferably 38-55 C.
  • the chemicals used to adjust the pH include but are not limited to NaOH, HCl, NH 3 and Na 2 CO 3 .
  • the appropriate enzyme is mixed with water and added to the contaminant. The dose is dependent on the type and level of contamination.
  • the enzyme is recirculated through the ion exchange vessel for an appropriate time. The recirculation time is dependent upon the enzyme used, adherence to optimum enzyme conditions and extent of contamination. The circulation time is typically in the range of 1-24 hours.
  • After treatment is complete the enzyme solution is rinsed with a solution typically water until the enzyme concentration in the vessel is exhausted.
  • the resin can now optionally be regenerated using standard chemcal procedures. Typical concentration and chemicals used for regeneration include: For a weak base anion type resin 4% NaOH solution at 96-112 kg/m 3 and 5%
  • N-t-CO j solution at 1 12-118 kg/m3 is recirculated for 30-60 minutes at 40 C.
  • 4% NaOH solution at 1 12-120 kg/m3 and 7% Na2CO3 solution at 80-96 kg/m3 is recirculated for 30-60 minutes at 40 C.
  • CONTAMINANT The present example illustrates the method used to remove the contaminant corn gluten protein from cation and anion ion exchange resin that could not be removed with either chemical treatment or water.
  • the resin is rinsed (Sweetened off) using water, adjusted to the optimum enzyme operating temperature.
  • the pH of the vessel is adjusted to 6.8 using a 5% sodium carbonate solution, which is near the enzyme optimum pH.
  • the enzyme used is a 0.5L peptidase (Neutrase). Thirty kg of peptidase is added per 1500 ft 3 of resin. This amount of enzyme is estimated to be 1% of the total amount of contaminant.
  • the enzyme is added via suction through the cation and anion vessels. The solution is recirculated through the vessels for a total time of four hours. The enzyme is then rinsed from the vessel. Samples of the enzyme rinse is analyzed for total protein content by standard methods. (Kjeldahl analysis (Standard Analytical Methods of the Members of the Corn Refiners Association, Method B-48). The analyzed solutions are obtained after each hour of circulation with the following results. The amount of enzyme present in the sample which would be measured as protein is subtracted.
  • the solution in the vessels become milky brown in appearance within five minutes of enzyme addition.
  • the values are extremely significant as prior to enzyme treatment, the protein present in the vessels could be seen through sight glasses on the vessels.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Preparation Of Compounds By Using Micro-Organisms (AREA)

Abstract

La présente invention concerne un procédé enzymatique utilisé pour épurer des résines, notamment des résines d'échange d'ions et de fractionnement. On peut utiliser le procédé seul ou en combinaison avec des procédés chimiques. Le procédé permet la production améliorée de liquides contenant des contaminants par exemple des protéines, des glucides, des lipides et des amidons résiduels non convertis nécessitant un traitement de fractionnement ou d'échange d'ions. L'invention concerne également l'utilisation de résines dans la production d'édulcorants à base de maïs, notamment de sirop de maïs et de sirop de maïs à teneur élevée en fructose.
EP97936972A 1996-07-30 1997-07-03 Procede enzymatique d'elimination des contaminants d'une resine d'echange d'ions et de fractionnement Withdrawn EP0915734A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US2286796P 1996-07-30 1996-07-30
US22867P 1996-07-30
PCT/US1997/012591 WO1998004344A1 (fr) 1996-07-30 1997-07-03 Procede enzymatique d'elimination des contaminants d'une resine d'echange d'ions et de fractionnement

Publications (1)

Publication Number Publication Date
EP0915734A1 true EP0915734A1 (fr) 1999-05-19

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Application Number Title Priority Date Filing Date
EP97936972A Withdrawn EP0915734A1 (fr) 1996-07-30 1997-07-03 Procede enzymatique d'elimination des contaminants d'une resine d'echange d'ions et de fractionnement

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Country Link
EP (1) EP0915734A1 (fr)
JP (1) JP2000516709A (fr)
CN (1) CN1226843A (fr)
AU (1) AU3960197A (fr)
WO (1) WO1998004344A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3350128B1 (fr) * 2015-09-15 2020-10-21 Dow Global Technologies LLC Procédé de régénération de résine acrylique
CN105332149B (zh) * 2015-10-21 2018-05-29 泉州市新空间装饰工程有限公司 一种张力可控的储纬器
CN112844345B (zh) * 2020-12-29 2023-07-18 无锡中天固废处置有限公司 一种活性炭吸附淀粉类废水后固废的处理方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5759641A (en) * 1980-09-26 1982-04-10 Japan Organo Co Ltd Regenerating method for strong acidic cation exchange resin
ATE183943T1 (de) * 1993-02-12 1999-09-15 Filtrox Ag Verfahren zur reinigung eines filterhilfsmittels durch zusatz von enzymen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9804344A1 *

Also Published As

Publication number Publication date
JP2000516709A (ja) 2000-12-12
CN1226843A (zh) 1999-08-25
WO1998004344A1 (fr) 1998-02-05
AU3960197A (en) 1998-02-20

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