# US 11,111,629 B2 · Methods of pulp fiber treatment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,111,629 B2 - Document ID: US11111629B2 - Status: Granted - Kind: B2 - Application number: 16/148,222 - Filed: 2018-10-01 - Published: 2019-01-31 - Granted: 2021-09-07 - Earliest claimed: 2015-12-07 - Assignees: Clean Chemistry, Inc. - Applicants: Clean Chemistry, Inc. - Inventors: Wayne E. Buschmann; Damon C. Waters - Web page: https://patentgrep.com/patent/US11111629B2 ## CPC - D21C 9/166: {with peracids} - C02F 1/722: {Oxidation by peroxides} - C02F 9/00: Multistage treatment of water, waste water or sewage - C12P 3/00: Preparation of elements or inorganic compounds except carbon dioxide {(recovery of carbon dioxides as by-products C12F3/02)} - D21C 9/1063: {with compounds not otherwise provided for, e.g. activated gases} - D21C 9/147: with oxygen or its allotropic modifications (D21C9/16 takes precedence) - C02F 1/008: {Control or steering systems not provided for elsewhere in subclass C02F} - C02F 1/02: by heating (methods of steam generation F22B; preheating boiler feed-water or accumulating preheated boiler feed-water F22D) - C02F 1/50: by addition or application of a germicide or by oligodynamic treatment {(C02F1/4606, C02F1/467, C02F1/76 take precedence)} - C02F 1/76: with halogens or compounds of halogens {(C02F1/4674 takes precedence)} - C02F 1/766: {by means of halogens other than chlorine or of halogenated compounds containing halogen other than chlorine} - C02F 2101/345: {Phenols} - C02F 2103/007: {Contaminated open waterways, rivers, lakes or ponds} - C02F 2103/023: {Water in cooling circuits} - C02F 2103/28: from the paper or cellulose industry - C02F 2103/32: from the food or foodstuff industry, e.g. brewery waste waters - C02F 2209/04: Oxidation reduction potential [ORP] - C02F 2209/36: Biological material, e.g. enzymes or ATP - C02F 2303/02: Odour removal or prevention of malodour - C02F 2303/04: Disinfection - C02F 2303/08: Corrosion inhibition - C02F 2303/20: Prevention of biofouling - D21C: PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) - C12P: FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE {(brewing of beer C12C; producing vinegar C12J; producing specific peptides or proteins C07K; producing enzymes C12N9/00; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification C12N15/00; measuring or testing processes involving enzymes or microorganisms C12Q; measuring or testing processes involving nucleic acid amplification reactions C12Q1/6844; fermentation processes to form a food composition, A21 or A23; compounds in general, see the relevant compound class, e.g. C01, C07)} ## Abstract In some embodiments, a method may include treating pulp in pulp and paper mills. The methods may include providing a peracetate oxidant solution and generating a reactive oxygen species. The peracetate solution may include peracetate anions and a peracid. In some embodiments, the peracetate solution may include a pH from about pH 10 to about pH 12. In some embodiments, the peracetate solution has a molar ratio of peracetate anions to peracid ranging from about 60:1 to about 6000:1. In some embodiments, the peracetate solution has a molar ratio of peracetate to hydrogen peroxide of greater than about 16:1. The peracetate oxidant solution may provide enhanced treatment methods of bleaching, brightening, and delignifying pulp fibers involving the use of peracetate oxidant solutions. ## Claims ### Claim 1 A method of treating pulp, the method comprising: delignifying the pulp in a delignification stage; after the delignification stage, contacting the pulp with a parent oxidant solution, the contacting comprising adding the parent oxidant solution to the pulp; and after the adding, mixing a mixture with the pulp with the added parent oxidant solution; and the parent oxidant solution being a peracetate oxidant solution to generate a reactive oxygen species in the mixture, wherein the peracetate oxidant solution as added to the pulp comprises: a pH in a range of from about 10 to about 12; peracetate anions and a peracid with a molar ratio of peracetate anions to peracid of from 60:1 to 6000:1; and a peracetate anion to hydrogen peroxide molar ratio greater than about 16:1; and wherein as added to the pulp the peracetate oxidant solution is at a higher pH than the pulp and during the mixing the mixture with the pulp and the peracetate oxidant solution comprises a pH in a range of from about pH 6 to about pH 11 and with the pH of the mixture decreasing over time as the mixing continues. ### Claim 2 (depends on 1) The method of claim 1, wherein during the contacting the pulp has a temperature from between about 50° C. to about 95° C. ### Claim 3 (depends on 2) The method of claim 2, wherein the temperature accelerates the generation of reactive oxygen species from the parent oxidant solution in the mixture. ### Claim 4 (depends on 1) The method of claim 1, further comprising extracting lignin from the pulp through action of the peracetate oxidant solution. ### Claim 5 (depends on 1) The method of claim 1, further comprising, after the contacting, bleaching the pulp with a bleaching sequence in which the pulp is bleached with chlorine dioxide. ### Claim 6 (depends on 1) The method of claim 1, wherein the pulp comprises a pulp consistency from 0.1 to 20% pulp fiber during the contacting. ### Claim 7 (depends on 1) The method of claim 1, wherein the reactive oxygen species generated is a singlet oxygen. ### Claim 8 (depends on 1) The method of claim 1, further comprising sequentially dosing the pulp with the peracetate oxidant solution. ### Claim 9 (depends on 1) The method of claim 1, wherein the delignification stage comprises oxygen delignification of the pulp. ### Claim 10 (depends on 1) The method of claim 1, wherein the delignification stage comprises sulfide digestion. ### Claim 11 (depends on 1) The method of claim 1, wherein the delignification stage does not include contacting the pulp with a peracetate solution. ### Claim 12 (depends on 1) The method of claim 1, wherein the method is in the absence of chlorine dioxide treatment prior to and during the contacting. ### Claim 13 A method of treating pulp, the method comprising: delignifying the pulp in a delignification stage; after the delignification stage, contacting the pulp with a parent oxidant solution, the contacting comprising adding the parent oxidant solution to the pulp; and after the adding, mixing a mixture with the pulp with the added parent oxidant solution; and the parent oxidant solution being a peracetate oxidant solution to generate a reactive oxygen species in the mixture, wherein the peracetate oxidant solution as added to the pulp comprises: a pH in a range of from about 10 to about 12; peracetate anions and a peracid with a molar ratio of peracetate anions to peracid of from 60:1 to 6000:1; and a peracetate anion to hydrogen peroxide molar ratio greater than about 16:1; and wherein the contacting the pulp comprises contacting the pulp during a washing stage. ### Claim 14 (depends on 13) The method of claim 13, wherein as added to the pulp the peracetate oxidant solution is at a higher pH than the pulp and during the mixing the mixture with the pulp and the peracetate oxidant solution comprises a pH in a range of from about pH 6 to about pH 11 and with the pH of the mixture decreasing over time as the mixing continues. ### Claim 15 A method of treating pulp, the method comprising: delignifying the pulp in a delignification stage; after the delignification stage, contacting the pulp with a parent oxidant solution, the contacting comprising adding the parent oxidant solution to the pulp; and after the adding, mixing a mixture with the pulp with the added parent oxidant solution; and the parent oxidant solution being a peracetate oxidant solution to generate a reactive oxygen species in the mixture, wherein the peracetate oxidant solution as added to the pulp comprises: a pH in a range of from about 10 to about 12; peracetate anions and a peracid with a molar ratio of peracetate anions to peracid of from 60:1 to 6000:1; and a peracetate anion to hydrogen peroxide molar ratio greater than about 16:1; and wherein the delignification stage comprises alkaline peroxide extraction. ### Claim 16 A method of treating pulp, the method comprising: delignifying the pulp in a delignification stage; after the delignification stage, contacting the pulp with a parent oxidant solution, the contacting comprising adding the parent oxidant solution to the pulp; and after the adding, mixing a mixture with the pulp with the added parent oxidant solution; and the parent oxidant solution being a peracetate oxidant solution to generate a reactive oxygen species in the mixture, wherein the peracetate oxidant solution as added to the pulp comprises: a pH in a range of from about 10 to about 12; peracetate anions and a peracid with a molar ratio of peracetate anions to peracid of from 60:1 to 6000:1; and a peracetate anion to hydrogen peroxide molar ratio greater than about 16:1; and wherein the delignification stage comprises enzymatic digestion.