US3458394A - Pulping wood chips with peracetic acid and chlorine dioxide - Google Patents
Pulping wood chips with peracetic acid and chlorine dioxide Download PDFInfo
- Publication number
- US3458394A US3458394A US494272A US3458394DA US3458394A US 3458394 A US3458394 A US 3458394A US 494272 A US494272 A US 494272A US 3458394D A US3458394D A US 3458394DA US 3458394 A US3458394 A US 3458394A
- Authority
- US
- United States
- Prior art keywords
- wood
- chlorine dioxide
- chips
- lignin
- peracetic acid
- 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.)
- Expired - Lifetime
Links
- 239000002023 wood Substances 0.000 title description 49
- OSVXSBDYLRYLIG-UHFFFAOYSA-N dioxidochlorine(.) Chemical compound O=Cl=O OSVXSBDYLRYLIG-UHFFFAOYSA-N 0.000 title description 40
- KFSLWBXXFJQRDL-UHFFFAOYSA-N Peracetic acid Chemical compound CC(=O)OO KFSLWBXXFJQRDL-UHFFFAOYSA-N 0.000 title description 26
- 239000004155 Chlorine dioxide Substances 0.000 title description 20
- 235000019398 chlorine dioxide Nutrition 0.000 title description 20
- 238000004537 pulping Methods 0.000 title description 16
- 238000000034 method Methods 0.000 description 33
- 229920005610 lignin Polymers 0.000 description 26
- 230000008569 process Effects 0.000 description 26
- 239000000243 solution Substances 0.000 description 21
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 18
- 239000001301 oxygen Substances 0.000 description 12
- 229910052760 oxygen Inorganic materials 0.000 description 12
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 11
- 229920002678 cellulose Polymers 0.000 description 9
- 239000001913 cellulose Substances 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 7
- -1 organic peroxide compound Chemical class 0.000 description 7
- 230000001590 oxidative effect Effects 0.000 description 6
- 239000011122 softwood Substances 0.000 description 6
- 241000894007 species Species 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 150000001875 compounds Chemical class 0.000 description 5
- 239000000835 fiber Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 229920002488 Hemicellulose Polymers 0.000 description 4
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 4
- 239000003513 alkali Substances 0.000 description 4
- 239000000460 chlorine Substances 0.000 description 4
- 230000029087 digestion Effects 0.000 description 4
- 239000011121 hardwood Substances 0.000 description 4
- TXXHDPDFNKHHGW-UHFFFAOYSA-N muconic acid Chemical compound OC(=O)C=CC=CC(O)=O TXXHDPDFNKHHGW-UHFFFAOYSA-N 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 241001070947 Fagus Species 0.000 description 3
- 235000010099 Fagus sylvatica Nutrition 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 229920001131 Pulp (paper) Polymers 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 238000005470 impregnation Methods 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 230000003381 solubilizing effect Effects 0.000 description 3
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 2
- TXXHDPDFNKHHGW-CCAGOZQPSA-N Muconic acid Natural products OC(=O)\C=C/C=C\C(O)=O TXXHDPDFNKHHGW-CCAGOZQPSA-N 0.000 description 2
- 241000218657 Picea Species 0.000 description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 2
- 241000592342 Tracheophyta Species 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000000908 ammonium hydroxide Substances 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- 238000010411 cooking Methods 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 239000007800 oxidant agent Substances 0.000 description 2
- 230000036284 oxygen consumption Effects 0.000 description 2
- 239000000123 paper Substances 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 150000004965 peroxy acids Chemical class 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 229910000029 sodium carbonate Inorganic materials 0.000 description 2
- 238000005063 solubilization Methods 0.000 description 2
- 230000007928 solubilization Effects 0.000 description 2
- 239000011885 synergistic combination Substances 0.000 description 2
- 235000007173 Abies balsamea Nutrition 0.000 description 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- 235000018185 Betula X alpestris Nutrition 0.000 description 1
- 235000018212 Betula X uliginosa Nutrition 0.000 description 1
- 241000219495 Betulaceae Species 0.000 description 1
- 241000218645 Cedrus Species 0.000 description 1
- 229920003043 Cellulose fiber Polymers 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 241000218631 Coniferophyta Species 0.000 description 1
- 241000218922 Magnoliophyta Species 0.000 description 1
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 1
- 241000018646 Pinus brutia Species 0.000 description 1
- 235000011613 Pinus brutia Nutrition 0.000 description 1
- 241000183024 Populus tremula Species 0.000 description 1
- 241000219492 Quercus Species 0.000 description 1
- 241000218685 Tsuga Species 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 125000002252 acyl group Chemical group 0.000 description 1
- 229910001854 alkali hydroxide Inorganic materials 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 150000004676 glycans Chemical class 0.000 description 1
- 159000000011 group IA salts Chemical class 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 239000002655 kraft paper Substances 0.000 description 1
- 239000012978 lignocellulosic material Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 150000001451 organic peroxides Chemical class 0.000 description 1
- 150000004967 organic peroxy acids Chemical class 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229920001282 polysaccharide Polymers 0.000 description 1
- 239000005017 polysaccharide Substances 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 229910052979 sodium sulfide Inorganic materials 0.000 description 1
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 238000006277 sulfonation reaction Methods 0.000 description 1
- 239000006228 supernatant Substances 0.000 description 1
- 230000002522 swelling effect Effects 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 239000010875 treated wood Substances 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C3/00—Pulping cellulose-containing materials
- D21C3/003—Pulping cellulose-containing materials with organic compounds
Definitions
- This invention pertains to pulping of lignocellulosic materials contained in the stems of vascular plants, and, more specifically, to the pulping of wood whereby syngeristically coacting liquor components are used to defiber cellulosic fibers with heretofore unobtaiued yield.
- this invention pertains to pulping of softwoods and hardwoods by means of an organic peroxygen solution which has been modified by the addition of chlorine dioxide. The products of the process are within the scope of the invention.
- Conventional wood pulping methods may be divided into two general classes: first, those dependent upon the reaction between lignin and sulfite solution in which the solubilization of lignin is accomplished by sulfonation and cleavage of the lignin molecule.
- the second class consists of the methods dependent upon reaction of lignin with alkali, preferably in the presence of sodium sulfide with solubilization resulting from highly polar groups of the lignin moiety so for-med.
- the chemical reactions in conventional pulping are carried out under rather drastic conditions of temperature, pressure and time.
- the normal conditions are 140 C. to 160 C., 90 to 110 p.s.i. and 6 to 10 hours.
- the normal conditions are 170 C. to 176 C., 100 to 135 psi and 2 to 4 hours.
- the present invention may be better understood by referring to the major components of wood and the stems of other vascular plants. These components are cellulose, hemicellulose and lignin. Cellulose component of wood is most resistant to chemical attack. In general, this greater resistance is the basis of present pulping methods. In order to loosen and disintegrate the wood structure, the removal of lignin is normally essential. However, the lignin component, if it could be rendered useful in paper manufacture would give higher yields.
- the hemicellulose component of the wood is a polysacice charide and is a colorless material similar to cellulose except for being more swellable in water. It is acceptable as an ingredient of paper pulp and for some purposes it has superior paper-making properties.
- the novel and surprising feature resides in the observation that exposure of wood, and especially softwood, to relatively small quantities of an oxidizing agent, such as organic peroxide compound in combination with a synergistically coacting chlorine dioxide, results in yields up to 89% based on wood and active oxygen consumption of less than that when either an organic peroxide or chlorine dioxide is used to defiber cellulose to a given and equal percent yield when employing either of the components by itself. Moreover, the novel results are achieved with reduced liquor-towood ratios.
- an oxidizing agent such as organic peroxide compound in combination with a synergistically coacting chlorine dioxide
- pulp obtained by the novel process is a chemical pulp and will likewise. use an insignificant amount of energy to liberate the cellulose fibers (when compared to mechanical or semi-chemical pulp). Liberation of the pulp in the present process is accomplished by using a dilute alkali solution on .the treated wood.
- An additional advantage of this process is a by-product which appears to be a dicarboxylic compound in nature, and is believed at this stage to be a muconic acid.
- the novel process described above has been accomplished by impregnating wood chips of the sizes normally employed in commercial pulp processes such as from about 0.05 to about A with a suflicient amount of an aqueous solution containing an organic peroxygen compound and chlorine dioxide.
- an organic peroxygen compound and chlorine dioxide Of the organic compounds, the peracids are preferred. These consist of performic, peracetic, perbutyric and perbenzoic. Of the acids, the peracetic is preferred because of its behavior and exhibited properties.
- a liquor-to-wood ratio of wood on a bone-dry basis is of from about 0.5 to about 1 and up to about to l.
- a preferred liquor-to-wood (L/W) ratio is of from 3:1 to 5:1.
- the chips are brought into contact with a solution under pressure. Thereafter excess liquor is removed to the extent that the liquor-to-wood ratio is reduced to about 1:1, the chips heated for about hour to about 1, or about 50 C. to 90 C., and washed with hot water. The washed chips are then treated with of from 1% to 5% sodium hydroxide solution at about 2:1 up to :1 liquor-to-wood ratios, but preferably at a ratio of from 2:1 to 5:1, for about /2 hour to about 1 /2 hours at a temperature from about 50 C. to about 125 C., preferably about 50 C. Thereafter, the digested chips are disintegrated in a distintegrator to obtain a pulp.
- Peroxygen compounds which are useful in the present process are those that are water soluble and stable or capble of stabilization at up to 50 C., but preferably up to 100 C. and consist generally of alkyl hydroperoxides, alkylperoxides, acyl hydroperoxides, acyl peroxides, acyl alkylperoxides, hydroxy alkylhydroperoxides, hydroxy alkylperoxides, ozonides, oxozonides, and alkylidene peroxides.
- those of short carbon atom chains in the alkyl moiety are preferred and especially those which are stable at the process conditions and in the impregnation environment used, and most preferably, those that have a high percentage of active oxygen in reference to their molecular Weight.
- the acyl hydroperoxides such as the performic, peracetic, perbutyric and perpropionic, pervaleric, percaproic, etc., are the preferred subgroup of compounds. Of these, peracetic acid is the most preferred species.
- the present process sequence is accomplished by the use of a solution of peracetic acid as the preferred species in conjunction with a chlorine dioxide 4 brought up is from about 30 C. to start and about 90 C. at the termination, but preferably at about C. at the termination of the digesting or oxidizing step when this temperature is maintained for about 15 minutes to about 120 minutes.
- a water washing step may follow the oxidizing step.
- an alkaline solution such as a solution of sodium hydroxide, potassium hydroxide and the soluble alkaline earth hydroxides may be employed at a concentration of from about 1% to about 5%, but preferably below 3%, to remove the lignin derivative material, e.g., muconic acid and other solubilized inconstants.
- Sodium hydroxide solution is preferred.
- Wood chips derived from softwoods (derived from some gymnosperms) and hardwoods (derived from some angiosperms) are useful in the present process.
- softwoods the coniferous species such as spruce, pine, hemlock, fir, cedar, etc.
- hardwoods those useful in the present pulping process are alder, aspen, beech, oak, gum, birch, etc.
- sodium hydroxide solutions are most suitable.
- Ammonium hydroxide and other alkali hydroxides and their alkaline salts such as sodium carbonate, sodium carbonate, etc., are applicable, but the cost factor and efficiency are not as great.
- Other materials similarly suitable for solubilizing lignin may be used for their specific properties such as ammonium hydroxide, because of its ease of recovery, and other amines for their solubility.
- Example 1 In Table I below, several pulp runs are illustrated using spruce wood in the form of chips. The first cook shows that when using no chlorine dioxide and effecting the cellulose impregnation without it, the total oxygen consumption and the yields are considerably lower when compared with cook No. 6. The same comparison applies when chlorine dioxide is used by itself in cook No. 2. This chlorine dioxide run also illustrates the inherent problems associated with chlorine dioxide solubility. In all the runs, a small amount of mechanical energy is needed to separate the fibers.
- a process for pulping lignincontaining wood chips comprising the steps of:
- step (a) is less than about :1, and wherein the liquor-to-wood ratio in step (c) is less than about 1.6:1.
- the liquors in all of the above cases are black and upon being acidified give a brown precipitate and brown supernatant liquor.
- the precipitate may be obtained by using the washed liquor from the first stage.
- the elfect of chlorine dioxideand peracetic acid results in an increase of pulp yield which is still obtained by a chemical defibering mechanism.
- the consumption of active oxygen to achieve a certain yield is reduced in both the hardwoods and softwoods.
- Novel papers obtained by the present process have the tensile properties depicted in Table I as measured by TAPPI methods T 205 M-58 and T 404 08-61.
- the pulp produced by this process has tensile properties varying with the yield. A very strong sheet can be obtained if the yield is around 70% but a less strong sheet if the yield is 90%. This process has the obvious advantage of yielding pulps of variable strength depending on the operating conditions employed.
- step (c) is in the range from about 0.8:1 to about 1.621.
Landscapes
- Paper (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US49427265A | 1965-10-08 | 1965-10-08 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3458394A true US3458394A (en) | 1969-07-29 |
Family
ID=23963806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US494272A Expired - Lifetime US3458394A (en) | 1965-10-08 | 1965-10-08 | Pulping wood chips with peracetic acid and chlorine dioxide |
Country Status (3)
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3709778A (en) * | 1971-01-12 | 1973-01-09 | Atlantic Richfield Co | Method for bleaching groundwood pulp with tertiary butyl hydroperoxide |
| WO1986005529A1 (en) * | 1985-03-22 | 1986-09-25 | Oy Keskuslaboratorio - Centrallaboratorium Ab | Process for preparing bleached pulp out of lignocellulosic raw material |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2492047A (en) * | 1946-03-30 | 1949-12-20 | Du Pont | Bleaching wood pulp |
| US2494542A (en) * | 1946-05-02 | 1950-01-17 | Niagara Alkali Company | Method of bleaching pulp |
| US2799580A (en) * | 1953-11-25 | 1957-07-16 | M H Treadwell Co Inc | Process for the disincrustation of fibrous vegetable materials |
| US2939813A (en) * | 1956-04-25 | 1960-06-07 | Columbia Cellulose Company Ltd | Pulping of lignocellulosic material |
| US3020197A (en) * | 1960-08-05 | 1962-02-06 | Allied Chem | Method for production of high brightness high strength wood pulps |
| US3085039A (en) * | 1960-08-23 | 1963-04-09 | Fmc Corp | Process for the treatment of wood |
| US3193445A (en) * | 1962-07-16 | 1965-07-06 | Pittsburgh Plate Glass Co | Method of bleaching cellulosic materials with hydrogen peroxide |
-
1965
- 1965-10-08 US US494272A patent/US3458394A/en not_active Expired - Lifetime
-
1966
- 1966-09-09 NO NO164661A patent/NO119509B/no unknown
- 1966-10-03 SE SE13322/66A patent/SE341653B/xx unknown
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2492047A (en) * | 1946-03-30 | 1949-12-20 | Du Pont | Bleaching wood pulp |
| US2494542A (en) * | 1946-05-02 | 1950-01-17 | Niagara Alkali Company | Method of bleaching pulp |
| US2799580A (en) * | 1953-11-25 | 1957-07-16 | M H Treadwell Co Inc | Process for the disincrustation of fibrous vegetable materials |
| US2939813A (en) * | 1956-04-25 | 1960-06-07 | Columbia Cellulose Company Ltd | Pulping of lignocellulosic material |
| US3020197A (en) * | 1960-08-05 | 1962-02-06 | Allied Chem | Method for production of high brightness high strength wood pulps |
| US3085039A (en) * | 1960-08-23 | 1963-04-09 | Fmc Corp | Process for the treatment of wood |
| US3193445A (en) * | 1962-07-16 | 1965-07-06 | Pittsburgh Plate Glass Co | Method of bleaching cellulosic materials with hydrogen peroxide |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3709778A (en) * | 1971-01-12 | 1973-01-09 | Atlantic Richfield Co | Method for bleaching groundwood pulp with tertiary butyl hydroperoxide |
| WO1986005529A1 (en) * | 1985-03-22 | 1986-09-25 | Oy Keskuslaboratorio - Centrallaboratorium Ab | Process for preparing bleached pulp out of lignocellulosic raw material |
Also Published As
| Publication number | Publication date |
|---|---|
| NO119509B (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | 1970-05-25 |
| SE341653B (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | 1972-01-10 |
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