US3446696A - Method of de-inking with a non-ionic detergent - Google Patents

Description

May 27, 1969 DETERGENT R. H. ILLINGWORTH METHOD OF DE-INKING WITH A NON-IONIC DETERGENT,

Filed May 9, 1962 WATER SOURCE REACTOR CHEST DILUTION WASTE PAPER WASHER a. THICKENER (3-STAGE) ACIDIFICATIONI WASTE EFFLUENT THICKENER WEB FORMING ROBERT H.

ACID

INVENTOR. ILLJ NG WORTH ATTCDRN EYS United States Patent 3,446,696 METHOD OF DE-INKING WITH A NON-IONIC DETERGENT 1 Robert H. Illingworth, Madison, N.J., assignor, by mesne assignments, to Evening News Publishing Company, Newark, N.J., a corporation of New Jersey Continuation-impart of applications Ser. No. 84,908, Jan. 25, 1961, Ser. No. 95,722, Mar. 14, 1961, and Ser. No. 95,723, Mar. 14, 1961. This application May 9, 1962, Ser. No. 193,448

Int. Cl. D21c /02, 3/20 US. Cl. 162-5 32 Claims This application is a continuation-in-part of the following applications, now abandoned: Ser. No. 84,908 filed Jan. 25, 1961; Ser. No. 95,722 filed Mar. 14, 1961; and Ser. No. 95,723 filed Mar. 14, 1961.

This invention relates to a process for recovering waste cellulosic material, and more particularly to an improved process for de-inking printed waste cellulosic stock.

Converting waste newspaper, magazine, and other types of printed waste cellulosic stock to a product capable of re-use in forming paper or other cellulosic products has been a much sought after goal. Although many processes for de-inking such printed cellulosic material have been proposed, in general, these have not proved commercially satisfactory. Many of these processes, for example, when tried on a commercial scale with the general run of waste newspaper and junk, fail to yield a pulp suitable for reuse as newsprint, magazine or book stock. The failure may be attributable to the fact that many of these processes drive a significant portion of the ink particles into the cellulosic fibers, thereby rendering the pulp gray and unsatisfactory for use except for the manufacture of low grade paper materials, for example, low grade packaging cartons. Other of these processes are so expensive, timeconsuming, laborious and complicated that they may not be carried out economically.

It is an object of the present invention to provide an improved method for de-inking printed cellulosic material so as to render such paper re-usable, for example, in the making of paper or other cellulosic products.

It is another object of the present invention to provide an improved process for de-inking waste paper that produces a pulp at least substantially equal, and often superior, in brightness, color and strength to that of the original pulp.

Other objects of the present invention will in part be clear and will in part appear hereinafter.

These and other objects are achieved by treating waste printed cellulosic material with an aqueous solution consisting essentially of water, and a non-ionic detergent of the alkyl phenol-ethylene oxide condensation product type. No particular care need be exercised in selecting the water employed. Thus, hard water having a carbonate hardness of 20 to 350 p.p.m. or even higher may be used without resorting to softening. It is one of the advantages of this invention that hard water may be used, thereby eliminating the costly, time-consuming water softening and water purification techniques ordinarily resorted to in previous de-inking processes.

If so desired, the water used may be treated to soften it. An example of soft water is water having a carbonate hardness of less than 15 p.p.m. and preferably less than 5 p.p.m., or between about 0 and 5 p.p.m. In producing such a soft Water, a harder water may either be treated with zeolite to reduce the hardness to the values indicated, or, alternatively, a sufficient amount of suitable softening agents may be added to reduce the carbonate hardness of the water to the indicated levels. Typical of such softeners are the phosphate salts of sodium, such as trisodium phosphate, tetrasodium pyro- 3,446,696 Patented May 27, 1969 phosphate, sodium hexametaphosphate, and the like. When water softening agents of the type described are employed, the treating solution consists essentially of water, softening agent, and a non-ionic detergent, the solution containing enough softening agent to reduce the carbonate hardness of the Water to below about 15 p.p.m., and preferably below 5 p.p.m., or between about 0 and 5 p.p.m.

The non-ionic detergents suitable for use are condensation products of an alkyl phenol and ethylene oxide. Especially suitable are compounds having the formula:

where R is an alkyl phenol radical having between 9 and 19 carbon atoms in the alkyl chain and n is an integer between 4 and 30 and preferably 8 to 15.

An especially suitable non-ionic detergent of the type described which may be used with both hard and soft water is an ethylene oxide adduct of dodecylphenol and has a formula corresponding to that indicated above. Another example of a non-ionic detergent which has been found particularly useful is the condensation product of nonylphenol and ethylene oxide and has the formula:

It will be clear from the foregoing that the weight percent of ethylene oxide Will vary with the value of n' and the length of the alkyl chain on the phenol. Thus, when the alkyl chain on the phenol contains 9 carbon atoms, i.e., nonyl phenol, the percent ethylene oxide will be about 50 percent when n equals 4, and about 70 percent when n equals 11. When the alkyl phenol contains 9 carbon atoms in the alkyl chain and n is 4, the minimum values for the alkyl chain length and n specified supra, the percent ethylene oxide will also be a minimum. Thus, the alkyl phenolethylene oxide condensation products disclosed supra will have at least 50 percent ethylene oxide.

The amount of non-ionic detergent employed should be carefully controlled. In terms of weight of dry paper being treated, the amount of this material may vary between about 1 and 2.5 percent, and preferably between about 1.5 and 2.0 percent. Especially good results are obtained when the amount of non-ionic wetting agent is at least about 1.5 percent by Weight of dry paper, and this amount appears to represent the optimum lower limit.

When softening agents are employed, the amount used will, of course, depend on the type of water employed. Generally, amounts of the softening agents varying between about 0.1 and 4 percent and usually between about 1.5 and 2.0 percent by weight of the dry cellulosic material will be suflicient.

The temperature of the treating solution may vary anywhere from room temperature, e.g., 40 to 70 R, up to the cloud point or volatilization temperature of the nonionic detergent. Although good results are achieved at room temperature, the de-inking has been found to pro ceed more rapidly when the treating solution is between about and F., and this temperature range is preferred.

If so desired the de-inking compositions of this invention may have incorporated therein an anionic detergent. Suitable synthetic anionic organic detergents useful in accordance with this invention are the water-soluble alkyl aryl sulfonates having relatively long chain alkyl groups. Generally, the alkyl chains may contain from about 9 to 19 carbon atoms. Such organic sulfonates are available commercially, especially as alkali alkyl aryl sulfonates having builders incorporated therein. By builders are meant additives which improve the performance of the sulfonates in their cleaning action, such as, for example, the various alkali phosphates and polyphosphates, alkali sulfates and the like.

When a non-ionic detergent is used in combination with an anionic detergent, the amount of each of these materials may vary between about 0.1 and 2 percent, and referably between about 0.25 and 0.75 percent. Especially good results are obtained when about 0.5 percent by weight of dry paper or dry pulp of each material is employed, and this amount is optimum.

Best results are achieved with the de-inking solutions described herein when they are alkaline in pH and it, therefore, is desirable that an alkali be included therein. Although any suitable alkali or alkaline earth metal hydroxide or salt may be employed, the alkali metal hydroxides and salts, such as sodium hydroxide, potassium hydroxide, soda ash and the like are preferred. Enough of the alkali should be added to bring the pH of the aqueous solution up to a pH of between about 7.0 and 10, or even higher, and preferably between about 8.5 and 9.5. Particularly good results are achieved when the pH is about 9.2 and this value appears to be optimum.

In preparing the treating solution water, either heated or at room temperature, as indicated above, is charged to the reactor or pulper and the non-ionic detergent added. The detergent is preferably added to the water prior to the addition of the waste paper or junk. If it is desired that soft water be used, when the water used has not been previously treated to reduce its hardness to the value indicated above for soft Water, the water softening agents herein described may be added with the detergent, or at any other suitable time, as indicated hereinabove.

To the resulting solution is added the printed paper, scrap or junk. The junk or newspaper waste may, if desired, be shredded by appropriate means prior to treatment. This, however, is not necessary, and the waste material may be added to the treating solution without shredding or without any subdivision in size whatsoever. It is one of the advantages of this invention that costly shredding or pulping techniques prior to de-inking need not be employed. Thus, the waste material to be de-inked is preferably added to the treating solution in its naturally dry condition, i.e., without being subjected to moisture or water other than that which is normally present in the atmosphere. Although de-inking will occur if the waste material is first slurried or pulped in water, in general it has been found that the results achieved are inferior to those obtained when the waste material is added to the treating solution in its naturally dry condition, i.e., in equilibrium with its natural atmospheric environment. Although not wanting to be restricted to this interpretation, it appears that wetting the waste material with water prior to subjecting it to the chemical treatment described herein has a tendency to set the ink and make it more difficult to remove from the cellulosic fibers.

The amount of the scrap or junk added to the treating solution should be controlled. In general, the percent of cellulosic material by weight of the aqueous treating solution should be below 10 percent and preferably below 6.0 percent, or between about 4.0 and 6.0 percent. Good results are obtained when the de-inking solution contains about 5 to 5.5 percent by weight of paper and this value appears to be optimum, The scrap is retained in the treating solution until substantial defiberization takes place. Depending upon the degree of agitation in the reactor, the time in the reactor may vary between about and 50 minutes, and is usually between about 20 and 40 minutes. When the de-inking composition contains an anionic detergent a shorter time may be used, e.g. 10 to 30 minutes.

Following treatment, the defibered material is dropped to a chest or other suitable reservoir, after which it is diluted with water to a solid content of between about 0.5 and 1.5 percent, preferably about 1.0 percent, based upon the solution weight.

Following dilution, the pulp is separated from the solution and washed and thickened by well known methods. The resulting pulp is then acidified to a pH of between about 4 and 6.5, preferably between about 4.5 and 5.5, thickened and then formed in o a Web.

This acidification step has been found to significantly increase the brightness of the paper produced from the recovered pulp, and also avoids the necessity of bleaching the pulp. Moreover, it has been discovered that acidification tends to set any residual ink particles which may be present, thereby preventing such particles from coming off on the felts and rolls during the web forming step. Such residual ink particles in the past have been found to create considerable difficulty and aggravation during web forming.

The recovered stock may be blended with fresh virgin sulfate or sulfite stock, or with additional recovered stock to make cellulosic articles, such as newspaper, and so forth.

A suitable arrangement for carrying out the de-inking process is illustrated in the accompanying drawing, which is a flow-sheet of the steps in a particularly suitable process.

As indicated in the drawing, water from an appropriate source is charged to a suitable reactor or pulper. The reactor or pulper used in the process is equipped with a stirrer or agitator of any appropriate shape which will agitate and defiber the cellulosic material. If desired, baffle plates may be attached to the interior of the reactor to assist the agitating action. When the solution is used at elevated temperature, the reactor is preferably equipped with a cover to retain heat in the receptacle. Also, suitable heat exchange means, such as coils, jackets, and so forth, may be provided if the solution is to be employed at the elevated temperatures indicated. As will be clear from the following description, pulping or defiberization, as well as separation of the ink particles, takes place in the reactor.

After the water has been charged to the reactor, the non-ionic detergent and where desired, the water softening agents and/ or anionic detergent are added and agitation continued until the materials are dissolved.

Waste paper, junk, or other printed cellulosic material is then added to the reactor.

After a suitable period of time in the reactor, the mixture is dropped to a storage chest which is preferably equipped with a suitable agitator. If desired, water may be charged to the chest to reduce the solid content of the mixture therein. The mixture from the chest is then diluted to the solid content indicated hereinabove, and washed and thickened in a well known manner as, for example by a Lancaster three-stage washer and thickener equipped with a 45 mesh wire screen. The pulp may be thickened to about a 5 percent solid consistency, or between about a 3 to 8 percent solid consistency in this manner. Co-current or counter-current washing, alone or in combination, may be used. The resulting pulp is then acidified to the pH indicated hereinabove by addition thereto of a dilute solution of a suitable acid, as for example, sulfuric acid, SO and so forth. The resulting pulp may be finally thickened and formed into a web. The number of thickening and washing steps preceding the acidification step, it should be understood, is not critical, and the number of such treatments will be governed largely by economics. Good results have been achieved, for example, by repeating the washing and thickening steps three times. Also, if desired, the pulp may be bleached, using a suitable bleaching agent following acidification. in this event, the pulp should be washed following bleaching. Ordinarily, however, bleaching is not required. When only acidification is used, the pulp need not be, and preferably is not, washed following acidification.

The nature of the present invention will be clear from the following examples:

Example 1 City water having a carbonate hardness of 119 ppm. is heated to F. and charged to the reactor. The reactor is an eight foot diameter hydrapulper, arranged for batch operation, and equipped with a 36 inch diameter rotor for operation at 247 r.p.rn. by a 40 HP. motor and one inch diameter extraction blades. It is also equipped with a hood to retain heat and with a steam line to retain a temperature of 130 F. Based on the weight of newspaper, 1.6 percent of an ethylene oxide adduct of dodecyl phenol is charged to the reactor and permitted to dissolve.

To the resulting solution is added about 5 percent by weight, based upon the weight of the solution, of nonshredded, dry newspaper scrap and junk.

The temperature of the resulting mixture is maintained at 135 F., and pulping is continued with stirring for 35 minutes. The pulp is then dropped to a chest, after which it is diluted with Water to give a mixture comprising about 1 percent by weight of pulp. The pulp is then thickened and washed by a Lancaster three-stage washer and thickener equipped with a 45 mesh wire screen. The solid content of pulp drawn off the Lancaster machine is about 5.0 percent by weight. The pulp is then acidified to a pH of 5.0 by addition of S gas. Following acidification, the pulp is again thickened and formed into a web.

The resulting pulp had a substantially white appearance and was of a quality suitable for blending with fresh virgin sulfate or sulfite stock to make newsprint.

Following the third wash, the pulp has a pH of 6.5. Samples of the pulp at this point were withdrawn from the process and formed into paper sheets. T.A.P.P.I. Standard brightness tests were run on the paper sheets. The sheets had an average T.A.P.P.I. Standard brightness of 56.

Paper sheets were also prepared from the pulp following acidification. Average T.A.P.P.I. Standard brightness on these sheets was 58.

Example 2 City water having a pH of 7.9 and a carbonate hardness of 119 p.p.m. is heated to 130 F. and charged to the reactor. The reactor is an eight foot diameter hydrapulper, arranged for batch operation, and equipped with a 36 inch diameter rotor for operation at 247 r.p.m. by a 40 HP. motor and one inch diameter extraction blades. It is also equipped with a hood to retain heat and with a steam line to retain a temperature of 130 F. Based on the weight of newspaper, 1.6 percent of an ethylene oxide adduct of nonyl phenol and 1.5 percent tetrasodium pyrophosphate are charged to the reactor and permitted to dissolve.

To the resulting solution is added about 5 Weight percent based upon the weight of the solution of nonshredded, dry newspaper scrap and junk.

The temperature of the resulting mixture is maintained at 135 F., and pulping is continued with stirring for 35 minutes. The pulp is then droppd to a chest, after which it is diluted with water to give a mixture comprising about 1 percent by weight of pulp. The pulp is then thickened and washed by a Lancaster three-stage washer and thickener equipped with a 45 mesh wire screen. The solid content of pulp drawn off the Lancaster machine is about 5.0 percent by weight. The pulp is then acidified to a pH of 5.0 by addition of S0 gas. Following acidification, the pulp is again thickened and formed into a Web.

The resulting pulp had a substantially white appearance and was of a quality suitable for blending with fresh virgin sulfate or sulfite stock to make newsprint.

Following the third wash, the pulp has a pH of 6.5. Samples of the pulp at this point were withdrawn from the process and formed into paper sheets. T.A.P.P.I. Standard brightness tests were run on the paper sheets. The sheets had a T.A.P.P.I. Standard brightness of 57.5.

Paper sheets were also prepared from the pulp-following acidification. T.A.P.P.I. Standard brightness on these sheets was 60.0.

Example 3 Example 2 is repeated with the exception that an ethylene oxide adduct of dodecyl phenol is substituted for the ethylene oxide of nonyl phenol as the non-ionic detergent. Similar results are obtained.

Example 4 Example 3 is repeated with the exception that the water used to prepare the de-inking solution is first treated with zeolite to reduce its carbonate hardness to 0.0 p.p.m. No water softener is employed in the de-inking solution.

The T.A.P.P.I. Standard brightness of paper sheets produced from pulp withdrawn from the process following the third Water Wash is 57.5 Paper sheets prepared from the pulp subjected to acidification to pH had a T.A.P.P.I. Standard brightness of 60.0.

Example 5 Purified water having less than one part per million of iron is heated to a temperature of to 0., care being taken that the maximum temperature indicated is not exceeded. Enough sodium hydroxide is added to give a pH of about 9.2. The amount of sodium hydroxide required to give this pH is about 0.5 percent, based on the weight of dry paper added.

There are then added to the heated alkali aqueous solution in an amount of 0.5 percent by weight respectively, an alkyl aryl sulfonate with an inorganic binder, and a non-ionic surface active agent which may be described as an ethylene oxide adduct of dodecyl phenol, e.g., a polyethylene ether of dodecyl phenol.

To the resulting alkaline solution is added about 5 percent by weight based upon the weight of the solution of newspaper scrap and junk.

The temperature of the resulting mixture is maintained between 110 and 140 F., and pulping is continued with stirring for 15 minutes. The pulp is then dropped to a chest, after which it is diluted with water to give a mixture comprising about 1 percent by weight of pulp. The pulp is then thickened on a 45-mesh screen and washed with water, following which it is acidified to a pH of 4.8 to 5.2 by treatment with a dilute solution of sulfuric acid. Following acidification, the pulp is again thickened after which it is formed into a web. The resulting pulp has a substantially white appearance and is of a quality suitable for blending with fresh virgin sulfate or sulfite stock, or with additional recovered stock, to make newsprint.

Example 6 Example 2 is repeated with the exception that the following chemicals are employed:

Pounds per ton Results similar to those of Example 2 are obtained.

Although in the description hereinabove the non-ionic detergent is added to the water, it should be understood that this material (and water softener and/or anionic detergent) may also be introduced into the water in association with the waste cellulosic material, as for example, by spraying the Waste material with the non-ionic detergent prior to introduction of the waste newspaper into the pulper or reactor.

Although in the above example a batch, or more properly, a semi-batch process is indicated, it should be understood that the de-inking may be carried out using a continuous process, as will be obvious to those skilled in the art.

The invention in its broader aspects is not limited to the specific compositions, steps and methods described, but departures may be made therefrom within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.

What is claimed:

1. The method of removing coloring matter from printed cellulosic material which comprises pulping the printed cellulosic material for a period of between about and 50 minutes in an aqueous solution consisting essentially of a non-ionic detergent of the alkylphenol-ethylene oxide condensation type, 1 to 2.5 percent based on the weight of cellulosic material, and the remainder hard water having a carbonate hardness of at least about p.p.m., the temperature of said solution being between about 110 and 140 F., and the amount of cellulosic material in said solution being between about 4.0 and 10.0 percent by weight of the aqueous solution.

2. The method of de-inking printed paper which comprises establishing an aqueous solution consisting essentially of a non-ionic detergent of the alkylphenol-ethylene oxide condensation type, in which the alkyl radical attached to the phenyl group has between 9 and 19 carbon atoms, in an amount of between 1 and :2.5 percent by weight of the dry paper added to the solution and the remainder hard water, the temperature of the solution being between about 110 and 140 F.; charging the dry printed paper to the aqueous solution in an amount of less than about 10 percent by weight of the aqueous solution; pulping the printed paper in said solution for a period of between about 10 and 50 minutes; diluting the resulting mixture to between about an 0.5 and 1.5 percent solid basis by addition of water thereto; washing and thickening the resulting pulp; and forming the resulting pulp into a web.

3. The method of de-inking printed paper which comprises establishing an aqueous mixture consisting essentially of water having a carbonate hardness of about 20 to 350 p.p.m. and :a non-ionic detergent which is a condensation product of ethylene oxide with dodecylphenol, in an amount of between 1 and 2.5 percent by weight of the dry paper added to the solution; the temperature of the solution being between about 110 and 140 F.; charging dry printed paper to the aqueous solution in an amount of between about 4.0 and 10.0 percent by weight of the aqueous solution; pulping the printed paper in said solution for a period of between about 10 and 50 minutes; diluting the resulting mixture to between about an 0.5 and 1.5 percent solid basis by addition of water thereto; thickening and washing the pulp; and forming the pulp into a web.

4. The method of claim 3 including acidifying the pulp to a pH of about 4.0 to 6.5 following washing.

5. The method of claim 3 wherein the amount of nonionic detergent in the solution is at least about 1.5 percent by weight of the dry paper added to the solution.

6. The method of claim 3 wherein the amount of printed paper added to the solution is between about 4.0 and 6.0 percent by weight of the solution.

7. The method of claim 1 wherein there is included in the aqueous solution enough of a water softening agent to reduce the carbonate hardness of the water below 15 p.p.m.

R. The method of claim 1 wherein there is included in the aqueous solution a water softener which is a member selected from the group consisting of trisodium phosphate, tetrasodium phosphate, sodium hexarnetaphosphate, and mixtures of the foregoing, in an amount of between about 0.1 to 4 percent by weight of the printed cellulosic material.

9. The method of claim 1 wherein an alkali is present in the aqueous solution in an amount suflicient to provide :a pH of between about 7.0 and 10.0.

10. The method of claim 9 wherein the pH is about 9.2.

11. The method of claim 9 wherein the alkali is a member selected from the group consisting of alkali metal hydroxide and soda ash.

12. The method of claim 1 wherein there is included in the aqueous solution between about 0.1 and 2 percent based on the weight of paper, of an alkyl aryl Sulfonate anionic detergent.

13. In a process for de-inking waste printed paper, the improvement which comprises treating the waste printed paper for between about 10 and 50 minutes in an aqueous alkaline solution having a pH of between about 7.0 and 10 and containing as the active de-inking agent about 1 to 2.5 percent by weight, based upon the weight of paper, of a non-ionic detergent corresponding to the formula:

wherein R is a radical of an alkyl phenol having 9 to 19 carbon atoms in the alkyl chain and n is an integer between 4 and 30, the temperature of the treating solution being between about room temperature and the cloud point of the non-ionic detergent.

14.,The method of claim 13 wherein R is a radical of dodecyl phenol and n is an integer between 8 and 15.

15. The method of claim 13 wherein said compound corresponds to the formula:

16. The method of claim 3 wherein there is included in the aqueous solution enough of a water softener to reduce the carbonate hardness of the water below about 15 p.p.m.

17. The method of claim 3 wherein there is included in the aqueous solution a water softener which is a member selected from the group consisting of trisodium phosphate, tetrasodium phosphate, sodium hexametaphosphate, and mixtures of the foregoing, in :an amount of between about 0.1 to 4 percent by weight of the printed cellulosic material.

18. The method of de-inking printed paper which comprises establishing an aqueous mixture consisting essentially of water having a carbonate hardness of :about 20 to 36 p.p.m. and a non-ionic detergent which is a condensation product of ethylene oxide with nonyl phenol, in an amount of between 1 and 2.5 percent by weight of the dry paper added to the solution; charging dry printed paper to the aqueous solution in an amount of between about 4 and 10 percent by weight of the aqueous solution; pulping the printed paper in said solution for a period of between about 10 and 50 minutes at a temperature of about to F.; diluting the resulting mixture to between about an 0.5 and 1.5 percent solid basis by addition of water thereto; thickening and washing the pulp; and forming the pulp into a web.

19. The method of claim 18 wherein there is included in the aqueous solution enough of a water softening agent to reduce the carbonate hardness of the water below about 15 p.p.m.

20. The method of claim 18 wherein there is included in the aqueous solution a water softening agent which is a member selected from the group consisting of trisodium phosphate, tetrasodium phosphate, sodium hexaimetaphosphate, and mixtures of the foregoing, in an amount of between about 0.1 to 4 percent by weight of the printed cellulosic material.

21. The process of separating the cellulosic fibers of printed paper from the ink therein contained 'which comprises the step of adding said separated printed paper in substantially dry form to a solution of water :and approximately 0.25 to 2.5% of a water soluble non-ionic surface active agent at a temperature of from about 90 to 140 F., forming a slurry thereby of from about 4% to 6% solids, substantially immediately agitating said slurry sufficiently to reduce said paper substantially to individual fibers, removing said fibers from said solution, and washing said fibers.

22. The process of claim 21 wherein said non-ionic surface active agent is an :alkyl phenyl ether of polyethylene glycol.

24. The process of claim 21 wherein said non-ionic.

surface active agent is an alkylphenolethylene oxide condensation product.

25. The process of claim 21 wherein said non-ionic surface active agent is an ethylene oxide condensate.

26. The process of claim 21 wherein said solution is maintained at about 110 to 140 F. with a concentration of non-ionic surface active agent of about 0.5%.

27. The process of making from newsprint waste a paper comprising the steps of adding printed paper in substantially dry form to :a solution of water and approximately 0.25 to 2.5% of a Water soluble non-ionic surface active agent at a temperature of from about 90 to 140 F., forming a slurry thereby of from about 4% to 6% solids, substantially immediately agitating said slurry sufficiently to reduce said paper substantially to individual fibers, removing said fibers from said solution, washing said fibers, and forming said fibers into paper.

28. The process of claim 27 wherein said non-ionic surface active agent is an alkyl phenyl ether of polyethylene glycol.

29. The process of claim 27 wherein said non-ionic surface active agent is an aryl alkyl polyether alcohol.

30. The process of claim 27 wherein said non-ionic surface active agent is an alkylphenolethylene oxide con densation product.

10 31. The process of claim 27 wherein said non-ionic surface active agent is an ethylene oxide condensate.

32; The process of claim 27 wherein said solution is maintained at about to F. with a concentration of non-ionic surface active agent of about 0.15%.

References Cited UNITED STATES PATENTS 3,069,307

OTHER REFERENCES Miskel, Surface Activity And Its Application To Paper, Tappi Sec, pages 233-238, June 29, 1944, 16215-8.

HOWARD R. CRANE, Primary Examiner.

U.S. Cl. X.R. 162-15 8

Claims (1)

1. 21. THE PROCESS OF SEPARATING THE CELLULOSIC FIBERS OF PRINTED PAPER FROM THE INK THEREIN CONTAINED WHICH COMPRISES THE STEP OF ADDING SAID SEPARATED PRINTED PAPER IN SUBSTANTIALLY DRY FORM TO A SOLUTION OF WATER AND APPROXIMATELY 0.25 TO 2.5% OF A WATER SOLUBLE NON-IONIC SURFACE ACTIVE AGENT AT A TEMPERATURE OF FROM ABOUT 90* TO 140*F., FORMING A SLURRY THEREBY OF FROM ABOUT 4% TO 6% SOLIDS, SUBSTANTIALLY IMMEDIATELY AGITATING SAID SLURRY SUFFICIENTLY TO REDUCE SAID PAPER SUBSTNTIALLY TO INDIVIDUAL FIBERS, REMOVING SAID FIBERS FROM SAID SOLUTION, AND WASHING SAID FIBERS.

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