Jan., 1913
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SOAP LYE AND SAPONIFICATION CRUDE GLYCERINS The following standard specifications were drawn up by the British Executive Committec on Crude Glycerin Analysis, and approved a t a general meeting of Crude Glycerin Makers, Buyers and Brokers, held in London o n October 3 , 1912 (C‘lzmn. i\‘ews, 106, 242) : Soap Lyes Crude Glycerin Analysis to bc made in accordancc with the International Standard Methods, 1911. Glycerol.-The standard shall be 80 per cent. glycerol. Any crude glycerin tendered, which tests 81 per cent. glycerol or over, shall be paid for at a p i - o rutu increase, calculated as from the standard of 80 per cent. Any crude glycerin which tests under 80 per cent. glycerol, but is 78 per cent. or over, shall be subject to a reduction of one and a half times the shortage, calculated a t pro rata price as from 80 per cent. If the test falls below 78 per cent., the buyer shall have the right of rejection. Ash.-The standard shall be I O per cent. In the event of the percentage of ash exceeding 10 per cent., but not exceeding 10.5 per cent., a percentage dcduction shall be made for the excess calculated as from I O per cent. a t pro ~ u t uprice; and if the percentage of ash exceeds 1 0 . j per cent., but does not exceed I I per cent., an additional percentage deduction shall be made equal to double the amount in :xcess of 10.5 per cent. If the amount of ash exceeds I I per cent., the buyer shall have the right to reject the parcel. Organic Residue.-The standard shall be 3 per cent. A percentage deduction shall be madt. of three timcs the amount in excess of the standard o f 3 pcr cent., calculated a t pro ratu price. The buyer shall h a w the right to reject any parcel lrhich tests over 3.75 per cent. Sapo)iijicatioii Crude G‘Iyceriri Analysis to be made in accordance with the International Standard Methods, 191I . Glj~cerol.-’I’he standard shall be 88 per cent. Any crude glycerin tendered, which tests 89 per cent. or over, shall be paid for a t a pro rata increase, calculated as from the standard of 88 per cent. Any crude glycerin which tests under 88 per cent., but is 86 per cent. or over, shall be subject to a reduction of one and a half times the shortage, calculated a t pro rata price as from 88 per cent. If the test falls below 86 per cent., the buyer shall have the right of rejection. , Ash.-The standard shall be 0.5 per cent. I n the event of the percentage of ash exceeding 0 . j per ccnt., but not exceeding 2.0 per cent., a percentage deduction shall be made equal to double the amount in excess of 0.5 per cent. If the amount of ash exceeds z per cent., thc buyer shall have the right to reject the parcel. Orgaizic Residue.-The standard shall be I per cent. A percentage deduction shall be made of twice the amonnt in excess of the standard of I per cent., calculated a t pro rata price. The buyer shall have the right to reject any parcel which tests over z per cent. THE PRODUCTION AND EMPLOYMENT O F DEXTRIN Parow (2. Spiritusind., 35, 5 0 7 , 519) discusses the production of dextrin and its use. The yearly production of dextrin in Germany amounts to about 30,000 tons; in 1911, thc quantity exported was 7,000 tons, although this was a poor year for potatoes. Dextrin is used as a substitute for gum acacia and gum arabic, in photography, as an excipient for dry extracts, for thickening mordants in printing fabrics, in the manufacture ol paper, in printing tapestries, for preparing felt, in the manufacture of printing rolls and printers’ halls, in the production o f inks, etc. Dextrin, which is produced from the starch of potatoes, corn, cassava and wheat, occurs in commerce in three fornis: a powder
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preserving the structure of the starch grains, agranular amorphous form, and a thick, milky liquid. Thc powdered form is obtained by heating starch meal alone or with 0 . I to 0.j per cent. of acid. In manufacturing liquid dextrins and “crystal gum” some producers use roasted dextrin instead of boiling the starch with dilute acids, as the dry heating of starch gives less sugar than boiling with acids. LVhen dry starch is roasted without the addition of aclds, temperatures of from tooo to z,joOC. arc cmployed, depending upon the desired color and solubility. If the starch is “prepared,” the roasting is conducted far I to 1’1, or z hours at I O O O to I25O C . , depending upon whether the product is to be white or yellowish. The preparation of thc starch consists in mixing with o . z ~ j - o . z oper cent. of hydrochloric or nitric acid, and subsequent drying and pulverization. Thc acid, diluted with water, may be introduced into a drum in which the starch is kcpt well agitated. After breaking up any lumps, the product is stored for about one day to permit of thorough impregnation of the acid, and then well dried, ground, sifted, and fed to the roasting apparatus. If suitable mixing plant is employed, the starch meal can, however, be acidified in the dry state and roasted immediqtely. For example, in Blunienthal’s apparatus, the meal is kept well agitated in a rotating drum, and the acid is injected in steam; in the method of Wulkan and Neumann, thc whole amount of acid is first mixed with G t o 8 per cent. of the starch, and this substantially dry mixture is then thoroughly mixed with the rest of the starch; Fielding completely dries the starch a t i o 0 to 80° C. before adding the acid; and Uhladd acidifies undried starch by allowing it, in the form of very fine flakes, to fall down a shaft into xhich the acid is injected in spray form, the product being again wcll mixed and dried. An easy control of the tcmperature is of vital importance, and is best attained by using roasting pans heated by oil, air or steam. I n the production of white dextrin, the product should be cooled very rapidly, and apparatus for this purpose has been invented by Uhland. I n a process devised by Pieper in 1894 a current of ozonized air is conducted through the roasting apparatus while the starch is being heated; and in Harweg’s process the starch powder, moistened with a sal1 solution, is exposed to an electric current. “Crystal gum,” or “Arabin,” is made by dissolving slightly darkened dextrin, obtained by roasting, in hot water, decolorizing with animal charcoal, filtering, evaporating to dryness, and grinding. Commercial dextrin generally contains I O to 1 2 per cent. of moisture, j per cent. of dextrose, and 0 . 2 per cent. of ash; it possesses an acidity corrcsponding to 3 cc. .V/r sodium hydroxide per roo grams. SOME ASPECTS OF THE FRENCH TURPENTINE INDUSTRY An account of some aspects of the resin and wood-pulp industries of France and the United States is given by J. F. Briggs in The Chemical TVorld, I , No. I I , 369, from which the following material relating to the French turpentine industry is taken. The French turpentine industry is confined to a triangular district called the “Landes,” about 3,500,ooo acres in extent, with Bordeaux as its principal town. About half this area, 1,750,000 acres, is forest-planted with the maritime pinc, and the yield of crude turpentine is about IOO,OOO tons annually. I n the United States, forests of long-leaf pinc ( P . palustris) and of certain other varieties occupy a strip about 125 miles wide along the coast of the Atlantic and Gulf of Mexico, cxtending on both sides of Florida to Virginia in the north and Texas in thc west. The forest districts represent about 7O,o
