Mar., 1921
T H E JOURNAL OF IiVDUSTRIAL A N D ENGINEERING CHEMISTRY RECOVERING NEWSPRINT11 By Charles Baskerville and Reston Stevenson
spectively. T h e results obtained on analyzing the fermented cultures are given in detail in Table IV. TABLB IV-FERMENTATIONO F SUCCESSIVE ACID EXTRACTS O F CORNCOBS (Products per 100 g . of Air-Dry Cobs) Total Volatile Volatile Total Non- Nonvolatile Acid as Acid from volatile Acid AcTd from Culture Extract Acetic Fermentation as Lactic Fermentation Number Number Grams Grams Grams Grams Control First 0 . 2 100 .... 0,3600 1 18-8 First 1.0020 0.7920 1.2150 0.8550 .... 1.5525 Control Second 1.9647 8.9002 6.9355 9.8235 8.2710 41-11 Second 9 . 0 0 21 7.0374 9,4738 7.9213 11 8-8 Second 9.1853 8.5841 7.2206 10.1366 1 18-8 Second AVERAGE.. . 9 . 0 2 9 2 7.0645 9.8113 8.2588 Control Third 1.0282 0,6426 .... 41-11 Third 4.6573 3.6291 5.4625 4.8195 118-8 Third 4.8838 3.8556 118-8 Third 4.8654 3.8373 5.2418 4:5992 AVERAGE. .4.8022 3 . 7 740 5.3520 4.7094 Total of Three 14.8334 13.8232 12.6315 16.3783 Extracts
.... ....
....
....
....
.....
The total acetic acid obtained is 14.8 g., of which 12.6 g. were produced b y the pentose fermenters. I n the case of t h e lactic acid the total amount is 16.4 g., of which 13.8 g. result from fermentation processes. Of the total sugar present, about 86 per cent is accounted for by these two products. Analysis of t h e fermented solutions shows only slight traces (0.1 t o 0.2 g.) of unfermented xylose, and strengthens the evidence for almost quantitative conversion of the sugar into these two products. Although this fermentation process has not yet been tested on a large scale, i t apparently offers a profitable means of utilizing corncobs. SUMMARY
Corncobs offer a promising raw material for the commercial production of acetic acid and lactic acid. These acids are obtained b y fermenting a sirup made from corncobs hydrolyzed with dilute sulfuric acid. This hydrolysis is easily brought about and yields from 30 t o 40 per cent of xylose. Crude xylose sirup is rapidly fermented b y certain rnicrobrganisms, for instance, Lactobacillus pentoaceticus 12. s p . , with the production of the above acids. The fermentation is almost quantitative, since 85 t o 90 per cent of the xylose can be accounted for b y the two acids. During the month of January 1921, thirty-two chemical concerns with an authorized capital of $50,000 or greater were organized, with a total investment of $22,295,000. Three concerns had an authorized capital of more than $1,000,000 : the Oselda Corporation, the American Chemical & Drug Co., and Breinig Brothers, as compared with two companies of such capitalization in December, two in November, and m e in October. The following table shows the authorized capital of new chemical, drug, and dye companies organized since 1915:
................................. ................................. ................................ ................................ ............................... .............................
1915 1916 1917. 1918. 1919.. 1920....
$ 65,565,000 99,314,000 146 160 000 73: 403 :OOO 112,173,000 487,148.900
The New York Central Lines have made a series of tests on corrosion of tie plates and the best method of reducing the amount of corrosion. The tests have been made over a period of six years on special steel, Bessemer steel, high carbon Bessemer steel, open-hearth steel, pure iron, and malleable iron, and it has been shown that the corrosion is least with a steel containing 10.25 per cent copper.
213
COLLEGEOR THE CITY O F N E W YQRK,N E W YORK,N. Y.
T h e patent literature a n d a recent book3 on waste paper recovery describe processes for de-inking paper without discriminating between newsprint stock and bookstock. T h e known processes which give satisfactory results for bookstock are not necessarily applicable t o old newspapers, primarily on account of t h e notable proportion of ground wood present in newsprint stock. This communication presents a process b y which t h e ink and binder and oil are removed from old newspapers with minimum injury t o t h e fiber, and the pulp is furnished ready for use again for newsprint. I n our experiments we used a laboratory pulper with electrically driven propeller, a wooden box with brass gauze bottom as washer, a brass disk-maker with brass gauze bottom, a book press, and air drying. This was according t o t h e practice familiar t o a paper mill laboratory. T h e following conclusions give t h e result of about seven hundred experiments. When printed papers, e . g., old newspapers, are mixed with water, and pulped and washed, t h e ink is partly removed. T h e greater p a r t of the ink remains, because : ( I ) The binder of the ink is not removed ( 2 ) The carbon of the ink is entrapped in the pulp (3) The carbon of the ink adheres t o the pulp A well-known method for bringing t h e binder into solution or emulsiqn, or a t least removing i t from t h e fiber, is t o treat t h e pulped paper with a water solution of a n alkali. Too little alkali does not entirely dissolve or emulsify t h e binder, nor does it liberate completely t h e pigment of t h e ink; on t h e other hand, too much alkali is harmful in t h a t i t yellows wood pulp, which is a prominent constituent in newspaper stock. Also, too excessive alkali tends t o mercerize t h e fiber, and too much alkali makes t h e carbon remain in t h e pulp in such a condition t h a t i t does not wash out. We have determined t h a t 60 lbs. of caustic soda per t o n of old newspapers is t h e optimum concentration of alkali. We have found t h a t 2 0 0 lbs. of soda ash per t o n of old newspapers gives as good, if not better, results, especially in regard t o t h e yellowing of t h e paper. T h e soda ash is much more easily handled. T h e use of alkali alone is not sufficient t o liberate t h e ink so t h a t i t can be washed away. We have worked out a method which completely frees t h e pulp from t h e ink, binder, oil, and pigment. It consists essentially in t h e addition t o t h e alkaline solution of American fuller’s earth, which remains in suspension or in colloidal solution. We have found t h a t approximately I O O lbs. of this earth t o a ton e
1 Presented before the Division o€ Industrial and Engineering Chemistry a t the 60th Meeting of the American Chemical Society, Chicago, Ill., September 6 to 10, 1920. * Patent applied for. 8 Strachan, “The Recovery and Re-manufacture of Waste Paper,” The Albany Press, Aberdeen, 1918,
214
T H E J O U R N A L OF I N D U S T R I A L A N D EIVGINEERING C H E M I S T R Y
of old newspapers i s sufficient, but if used in greater proportion, the effect is slightly better. T h e effect of the suspended material appears t o be a double one: i t removes t h e oils of t h e binder, and i t attracts the carbon away from t h e pulp and holds it. Upon subsequent washing with water t h e pulp may be retained b y a gauze or screen, a n d t h e minute particles of suspended material which hold t h e finely dispersed carbon and some oil are washed away. The best temperature for the procedure is about 5 0 ’ C. The less t h e concentration of t h e pulp, while t h e ratio of chemicals t o old papers remains constant, the greater is the de-inking effect. For practical reasons, a pulp is rarely less t h a n 2 per cent. T h e alkali and suspended material should be placed in t h e pulping machine with the water and heated t o s o o C. before the addition of t h e old newspapers. T h e paper must be perfectly pulped, which may be accomplished by various machines within a period of less t h a n one hour. The pulp must be thoroughly washed, requiring about one-fourth less water t h a n f o r bookstock. The resulting product is free from carbon and oil, and has only a faint yellow coloration. I t is ready for immediate use for making newspaper. The product obtained described in t h e last paragraph may be bleached by treatment with a solution of sulfur dioxide, which gives a product as white, if not whiter, t h a n t h e original unprinted paper. I n practice t h e bleaching has been accomplished in ~j min. b y the use of 20 lbs. of sulfur dioxide in cord water, per ton of old papers. The United States Civil Service Commission has announced examinations for metallurgists a t $3000 to $3600 per year and assistant metallurgists a t $2000 to $3000 per year, to fill vacancies in the Bureau of Mines a t Pittsburgh, Pa., and elsewhere. Candidates will be rated on (1) education, training and experience, and (2) writings (to be filed with the application). Applications will be received until the hour of closing business on April 5 , 1921. An examination has also been announced for laboratory assistants to fill vacanciFs in the Bureau of Standards a t $1200 to $1380 per year. Competitors will be rated in the following optional subjects : advanced general physics, electrical engineering, civil and mechanical engineering, chemical engineering, paper technology, textile technology, ceramics, physical metallurgy, physics, and chemistry, and will be rated on (1) elementary physics, chemistry, and mathematics, (2) optional subjects, and (3) general education, experience, and fitness. Applications will be received until further notice. Examinations will also be given for laboratory assistant, junior grade, a t $1000, and senior aid a t $900, to fill vacancies in the Bureau of Standards. Competitors will be rated on ( I ) physics and chemistry, (2) mathematics, (3) mechanical drawing, and (4) general education and experience. Applications will be received until further notice. Examinations have also been announced for microallalysts to fill vacancies in the Bureau of Chemistry a t $1200 to $1800 a year. Competitors will be rated on (1) education, training, and experience, and (2) thesis, reports or publications to be filed with application. Applications must be filed with the Civil Service Commission, Washington, D. C., by the hour of closing business on March 15, 1921.
VoI. 13, NQ.3
REGENERATING BOOKSTOCK’ By Charles Baskerville and C. M. Joyce COLLEGE OF THE CITY
OF
NEW YORK,N E W YORK,N. Y.
The enormously increasing output of magazines and trade journals, and a somewhat less large, b u t growing, production of books have created greater demands for book and magazine paper, which herein is collectively designated “bookstock.” With t h e exception of t h e cheaper grades of magazines, sulfite, soda, or sulfate pulp constitutes t h e larger portion of t h e cellulosic basis of the paper used. Some mechanical pulp is used in the cheap grades of magazines and light reading matter. Bookstock carries more or less filler and sizing, very variable in character and quantity. Other cellulose fibers, cotton, linen rags, esparto, etc., enter into book paper, which may become a part of a n assemblage of waste paper. Inks of various compositions and colors have been used on the collected waste. T h e economies involved in “Recovery a n d Remanufacture of Waste Paper”2 are interestingly brought out by Strachan, although he does not deal with a n important phase of t h e subject particularly of concern in t h e United States. The reworking of waste paper for t h e manufacture of box-board, roofing, etc., has developed t o a considerable industry in the United States, and t h e demand for such promises increasing growth. A marked differential for boxboard, of immaterial color, and sheets for printing mill undoubtedly always obtain, but ‘whether i t will economically carry the burden of regeneration is a question debated, but as yet unsettled, for a general policy in national conservation by some of t h e largest paper producers in this country. However, a t this particular time and for some years t o come, t h e regeneration of bookstock means conservation and profit. Various processes, either mechanical or chemical in nature, or both, have been proposed for special papers (photographic, waxed, etc.) and some of t h e m are in practical use t o a limited extent. Many of t h e processes, when tried on a commercial scale mrith the general run of waste paper, fail t o give t h e superior pulp desired for book paper. The failure is due in some instances t o t h e fact t h a t in the mechanical pulping of t h e stock the ink pigments are driven into the fibers, necessitating drastic treatment for separation, which shortens a n d weakens the fibers, as well as incurring (uneconomical) losses in washing t h e pulp. To secure t h e best results mechanically, the fibers require t o be loosened and then drawn, not torn, from the matte. Devices have been constructed t o meet the mechanical difficulty, b u t they involve time a n d power factors with mounting costs of operation. Sormally bookstock is a cellulosic fiber which has had severe chemical treatment. On t h e principle t h a t t h e binder of printing ink was a saponifiable oil, caustic solutions have been and are used t o “lift” t h e 1 Presented before the Division of Industrial and Engineering Chernistry a t the 60th Meeting of the American Chemical Society, Chicago,. 111, September 6 t o IO, 1920. 2 James Strachan, 191 8.
