Progress of the Chemistry of Papermaking - Industrial & Engineering

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April,

1912

T H E JOLR.VAL OF I L ~ 7 D U S T R I AA-YD L E-VGI-YEERI.YG C H E A I I I S T R l ’ .

307

CURRENT INDUSTRIAL NEWS

1

B Y W. A. HAMOR.

PROGRESS OF THE CHEMISTRY O F PAPERMAKING. Arthur D . Little presented a full report on this subject a t the Thirtyfifth Annual Meeting of the -4merican Paper and Pulp -4ssociation, February I j , 1912 (see Paper 6, S o . I O , p. 25), from iyhich the folloxing material is taken. As in a number of other industries-c. g., in glass manufacture -paper-making in the United States is still too frequently regarded as a hereditary art, while in Germany i t has become a science. The extent to which the industry has established itself upon a scientific basis is evidenced in the special number of the Papicrjabyikaizt, published in June, 1911, and “the publication as a whole cannot fail to impress any thoughtful American paper-maker with the seriousness of the competition which he will ultimately be called upon to meet.” Further evidence of the status of paper-making in Germany is had from the 1911 Proceediiigs of thc T-crein dev Zcllstoff w i d Papier Chemiker, wherein abstracts of 305 scientific studies covering almost the whole field of pulp- and paper-making are given, and “at least one other volume will be required to complete the record for the year.” The report of LVilliam Raitt, cellulose expert to the India Provinces Exhibition of 1910, published in 1911, contains results of studies on about forty specimens of wood to determine their suitability for pulp-making. These investigations included trial cooks by the standard chemical processes, and Riatt found the sulphate process most generally effective. Riatt concluded t h a t the following species offer the most promising fields for further investigation: Picea moriiida (spruce) : Abies pindrow (silver fir) ; BoinEax inalabaricuna ; Trewia zudifiora ; Salix tetrasperma (willow); and Butea froiidosa. His study of the Indian grasses s h o m that several of these are available in large quantity and furnish excellent sources of paper stock; and he also found t h a t the sulphate process, a t any rate with certain species, is adapted for the reduction of bamboo, yielding pulp of such good color t h a t it is immediately available for halfbleached papers. The subject of bamboo as a substitute for wood is to be exhaustively studied a t the Indian Forest Research Institute, Dehra Doon. This is of especial interest to Americans in t h a t Richmond has called attention to Philippine bamboo as one of the most promising substitutes for wood for papermaking. Richmond prefers the soda process for its treatment and reports the yield to be 45 per cent. The straw paper industry, which is highly developed in France, has been described by Abadie. Many different kinds of paper are produced from straw, and in the Limousin paper is made from this material without cooking. Manufacturers in the southwest of France cook the stran- in rotary digesters for about four hours with milk of lime. American paper-makers have been urged t o give a more general consideration of esparto, which, according to the experience of English paper-makers, stands in a class by itself as a raw material for the manufacture of high-grade book papers. Great quantities of esparto remain untouched in Algeria for lack of a market. The fiber from the inner bark of the baobab or monkeybread tree is also “deserving of more general utilization.’’ Among other materials, cottonwood is said to yield about 43 per cent. of absolutely dry fiber by the sulphite process. The most important development of 1911 in connection with paper-making is considered to be the prospect opened out by the new Simmons sugar process of obtaining bagasse or waste sugar cane fiber in great quantities and in a form particularly available as a ran- material for paper-making. The large supply of waste fiber obtained under the new process is substantially free from pith, is reduced very easily by the soda process, and yields a pulp suitable for the manufacture of book and printing

papers. Cornstalk or maize fiber is said to still have its advocates. The year marks no notable technical advance in the manufacture of sulphite fiber, but nevertheless considerable attention has been given to the problem of the utilization of waste sulphite liquors. The most important development in this direction is a process introduced in Sweden wherein a n impure grade of ethyl alcohol is produced by fermentation of the waste liquor after neutralization with lime. However, this process holds out no hope of avoiding the nuisance created by the waste liquors, since distillery-slop is far more objectionable than the original waste liquor, owing to the presence in it of large quantities of dead yeast. I n Germany, attempts are being made to utilize concentrated lyes, after eliminating the sulphurous acid, for cattle feed, but such utilization has not so far been found profitable. The employment of a concentrated liquor for tanning in connection with tannin extracts continues to a certain extent. A4method of utilization entitled to careful study is t h a t of Vogel, who recommended t h a t the waste liquor be evaporated, mixed with coal, and then burned. “Saduyn,” prepared from the waste lyes of sulphite mills, treated a t about 100’ C. with sodium chloride, is said t o be used in the form of a solution for saturating porous material for the absorption of the vapors of acrolein and other gases in the exhaust of motor cars. Two kg. of the powder is stated to be sufficient for a’motor vehicle run of 600 km. The chemistry of the sulphate process was discussed by Klason 2nd Segerfelt (Papieufabrikant, September, 19I I). These authors point out that the yields of fiber by the sulphate method are about 5o.per cent., while those by the soda process are 37 per cent. With regard to the formation of mercaptan in the sulphate process, i t has been proposed t h a t this compound be destroyed by nitrous gases. At Skutskar, Sweden, the Rinman soda process is in use; soda is recovered by precipitating the organic matter from the waste liquor by means of carbon dioxide in the presence of sodium chloride, and the precipitated material is distilled for the production of acetone and wood alcohol. It has been proposed that Epsom salt be substituted for alum in rosin sizing. Pauli and also Klemm conclude that, although magnesium sulphate is not to be regarded as a complete substitute for alum, it may replace a considerable proportion of the alum used when used concurrently therewith. Little points out in this connection that in most mills much more alum than is necessary is commonly used. I n coloring, indanthrene blue has been introduced as a substitute for ultramarine. When this dye is employed, i t is said to be possible to obtain a back water free from color. I t has been pointed out by Lehman that the waste water loss from paper mills frequently amounts to IO per cent. of the materials used, and t h a t of this loss fully 90 per cent. is recoverable, even by simple sedimentation methods. Little urges the establishment of a school ofjpaper-making in this country. It is stated that the matter has been taken up by the Boston Paper Trade Association.

RECENT INVESTIGATIONS ON ALLOYS. Advance proofs of papers to be presented before the Institute of Metals, issued January, 1912, contain much of interest to the industrial chemist. Abstracts of several of thcse follow. Rosenhain, in a discussion on the “Nomenclature of Alloys,” directs attention to the confusion which exists at present in the naming of alloys, especially in the use of the terms “brass” and “bronze,” which are sometimes employed in contradiction. A system is suggested in which the class name “brass” includes all alloys whose principal constituents are copper and zinc, and “bronze” those containing copper and tin; and when other