Methods of using combinations of a lipase and an oxidant for pitch control in paper making processes and products thereof
A method is provided for controlling deposit-forming contaminants that comprise pitch or other fiber components which can interfere with the processing of the fibers, reduce paper quality, or both in papermaking systems. The method includes contacting fibers with a lipase and at least one peroxide source-free oxidant, and optionally nonionic surfactant, to liberate the organic contaminants from the fibers. Paper products of the method are also provided.
1. A method for controlling deposition of organic contaminants from fibers in paper making systems, comprising treating an aqueous suspension containing fibers with at least one lipase and at least one peroxide source-free oxidant, wherein the organic contaminants comprise one or more pitch components, and the at least one peroxide source-free oxidant comprises a haloamine, a halamine sulfonamide, an alkali hypohalite salt, an alkaline earth hypohalite salt, a hypohalous acid, chlorine dioxide, a diatomic halogen, a halogenated hydantoin, a halogenated isocyanurate, a halo-oxazolidinone, or any combinations thereof.
2. The method of claim 1 , wherein the treating is for a sufficient time and in sufficient amount to provide treated fibers from which organic contaminants liberate from the fibers in greater amount than where the fibers are treated with the lipase and without the at least one peroxide source-free oxidant, wherein the organic contaminants comprise one or more pitch components.
3. The method of claim 1 , wherein the at least one peroxide source-free oxidant is a halogen-containing oxidant.
4. The method of claim 1 , wherein the at least one peroxide source-free oxidant is a haloamine, a halamine sulfonamide, an alkali hypohalite salt, an alkaline earth hypohalite salt, a hypohalous acid, chlorine dioxide, a diatomic halogen, a halogenated hydantoin, a halogenated isocyanurate, a halo-oxazolidinone, or any combinations thereof.
5. The method of claim 1 , wherein the lipase is a triacylglycerol (TAG) lipase.
6. The method of claim 1 , wherein the lipase is derived from a strain of Candida.
7. The method of claim 1 , wherein the fibers comprise virgin cellulosic fibers.
8. The method of claim 1 , wherein the treating removes at least 50% by weight of total pitch components present in the fibers prior to the treating.
9. The method of claim 1 , wherein the lipase and the at least one peroxide source-free oxidant are added to the aqueous suspension in an amount providing from about 0.01 ppm by weight to about 500 ppm by weight lipase and from about 0.05 ppm by weight to about 1000 ppm by weight at least one peroxide source-free oxidant in the aqueous suspension.
10. The method of claim 1 , further comprising treating the aqueous suspension with at least one nonionic surfactant in combination with the lipase and the at least one peroxide source-free oxidant.
11. The method of claim 10 , wherein the nonionic surfactant is a poloxamer.
12. The method of claim 10 , wherein the nonionic surfactant is a poloxamer having an HLB value of 16 or more.
13. The method of claim 10 , wherein the lipase, the at least one peroxide source-free oxidant, and the non-ionic surfactant are added in an amount providing from about 0.01 ppm to about 500 ppm by weight lipase and from about 0.05 ppm to about 1000 ppm by weight at least one peroxide source-free oxidant, and from about 0.001 to about 5.0 lb./ton dry fiber nonionic surfactant, in the aqueous suspension.
14. The method of claim 10 , further comprising forming the fibers into a paper product.
15. The method of claim 10 , wherein said at least one lipase and said at least one nonionic surfactant are added separately from any peroxide-free oxidant, and said at least one peroxide source-free oxidant is added separately from any lipase and nonionic surfactant, to said aqueous suspension containing fibers.
16. The method of claim 10 , wherein the nonionic surfactant is a PLURONIC® copolymer.
17. The method of claim 16 , wherein the PLURONIC® copolymer comprises PLURONIC® F38, PLURONIC® F68, PLURONIC® F88, PLURONIC® F98, PLURONIC® F87, PLURONIC® P105, or PLURONIC® F127.
18. The method of claim 16 , wherein the PLURONIC® copolymer comprises PLURONIC® F108.
19. The method of claim 1 , wherein the lipase is added in an amount providing from about 0.1 pound to about 1.5 pounds lipase per ton of dry fiber.
20. The method of claim 1 , wherein the aqueous suspension is a pulp.
21. The method of claim 1 , wherein the lipase and the at least one peroxide source-free oxidant are added to the aqueous suspension prior to a pulping stage.
22. The method of claim 1 , wherein the lipase and the at least one peroxide source-free oxidant are added to the aqueous suspension during a pulping stage.
23. The method of claim 1 , wherein the aqueous suspension is a papermaking stock.
24. The method of claim 1 , wherein the lipase and the at least one peroxide source-free oxidant are added to the aqueous suspension during or before a stock preparation stage.
25. The method of claim 1 , wherein the lipase and the at least one peroxide source-free oxidant are added prior to introduction of the aqueous suspension to a paper machine headbox.
26. The method of claim 1 , wherein the lipase and the at least one peroxide source-free oxidant are added to paper machine white water.
27. The method of claim 1 , wherein the aqueous suspension containing the lipase and the at least one peroxide source-free oxidant is in contact with the fibers for a time of from about 30 minutes to about 48 hours.
28. The method of claim 1 , further comprising forming the fibers into a paper product.
29. The method of claim 28 , wherein the paper product is paper, linerboard, tissue, corrugated paperboard, or any combinations thereof.
30. The method of claim 1 , wherein said at least one lipase is added separately from any peroxide-free oxidant, and said at least one peroxide source-free oxidant is added separately from any lipase, to said aqueous suspension containing fibers.
31. The method of claim 1 , wherein the at least one peroxide source-free oxidant is a haloamine.
32. The method of claim 31 , wherein the haloamine is monochloramine (NH 2 Cl), dichloramine (NHCl 2 ), trichloramine (NCl 3 ), monobromamine (NH 2 Br), dibromamine (NHBr 2 ), tribromamine (NBr 3 ), monoiodamine (NH 2 I), diiodamine (NHI 2 ), triiodamine (NI 3 ), or any combination thereof.
33. The method of claim 1 , wherein the at least one peroxide source-free oxidant is an N-halamine sulfonamide.
34. The method of claim 33 , wherein the N-halamine sulfonamide comprises chloramine T (sodium-N-chloro-p-toluenesulfonamide), dichloramine-T (N,N-dichloro-p-toluenesulfonamide), or both.
35. The method of claim 1 , wherein the at least one peroxide source-free oxidant is an alkali hypohalite.
36. The method of claim 35 , wherein the alkali hypohalite comprises sodium hypochlorite (NaOCl), potassium hypochlorite (KOCl), lithium hypochlorite (LiOCl), sodium hypobromite (NaOBr), potassium hypobromite (KOBr), lithium hypobromite (LiOBr), sodium hypoiodite (NaOI), potassium hypoiodite (KOI), lithium hypoiodite (LiOI), sodium hypofluorite (NaOF), potassium hypofluorite (KOF), lithium hypofluorite (LiOF), or any combination thereof.
37. The method of claim 1 , wherein the at least one peroxide source-free oxidant is an alkaline earth hypohalite.
38. The method of claim 37 , wherein the alkaline earth hypohalite comprises calcium hypochlorite (Ca(ClO) 2 ), calcium hypobromite (Ca(BrO) 2 ), calcium hypoiodite (Ca(IO) 2 ), calcium hypofluorite (Ca(FO) 2 ), magnesium hypochlorite (Mg(ClO) 2 ), magnesium hypobromite (Mg(BrO) 2 ), magnesium hypoiodite (Mg(IO) 2 ), magnesium hypofluorite (Mg(FO) 2 ), or any combination thereof.
39. The method of claim 1 , wherein the at least one peroxide source-free oxidant is a hypohalous acid.
40. The method of claim 39 , wherein the hypohalous acid comprises hypochlorous acid (HOCl), hypobromous acid (HOBr), hypoiodous acid (HOI), hypofluorous acid (HOF), or any combination thereof.
41. The method of claim 1 , wherein the at least one peroxide source-free oxidant is chlorine dioxide (ClO 2 ).
42. The method of claim 1 , wherein the at least one peroxide source-free oxidant is a diatomic halogen.
43. The method of claim 42 , wherein the diatomic halogen comprises chlorine (Cl 2 ), bromine (Br 2 ), iodine (I 2 ), fluorine (F 2 ), or any combination thereof.
44. The method of claim 1 , wherein the at least one peroxide source-free oxidant comprises a halogenated isocyanuric acid.
45. The method of claim 44 , wherein the halogenated isocyanuric acid comprises dichloroisocyanuric acid and its sodium and potassium salts, and trichloroisocyanuric acid, or any combination thereof.
46. The method of claim 1 , wherein the at least one peroxide source-free oxidant is a chlorinated or brominated hydantoin.
47. The method of claim 46 , wherein the chlorinated or brominated hydantoin is 1,3-dibromo-5,5-dimethylhydantoin.
48. The method of claim 1 , wherein the at least one peroxide source-free oxidant is a halo-oxazolidinone.
49. The method of claim 48 , wherein the halo-oxazolidinone comprises an N-halo-2-oxazolidinone, an N,N′-dihalo-2-imidazolidinone, or both.
50. The method of claim 1 , wherein the lipase comprises Resinase NT, Resinase HT, NovoCor® ADL, Greasex 50L, Optimyze®, Buzyme® 2515, or Buzyme® 2517.
51. The method of claim 1 , wherein the lipase comprises Resinase A2X.