July,
1912
T H E J O U R N A L OF I N D U S T R I A L AAYD ESGI,YEERIi\'G
some water to insure overflow of the entire froth mass. The separated froth is subjected to a cleansing operation which consists i n , reagitating the concentrated material to free impurities entrapped therewith and permit the concentrates to
I
CHE41/IISTRY .
553
MANUFACTURE OF ISOPRENE. U. S. Patent No. 1,022,338, to Oswald Silberrad, of Buckhurst Hill, England. This is a process for the depolymerization of turpentine oil for the production of isoprene. The invention consists in subjecting turpentine oil vapor to the action of heat having the pressure in the apparatus considerably below atmospheric pressure. The apparatus, in which the process is carried out, consists of a heating coil, a , inside a heating chamber, 6, heated by the products of combustion from a number of gas burners, c, using electric pyrometers, d , d , to determine the temperature. From
again form a froth. This froth is overflowed without any free flowing water and the settled impurities and the part of the froth not carried into the overflow is returned to the part of the pulp which is undergoing the separation treatment. METHOD OF RECOVERING RESIN FROM WASTE PRODUCTS. U. S. Patent No. 1,022,194, to Frank L. Huggins, of Wilmington, N. C., Assignor of one-half to John P. Moore, Jr., of Wilmington, N. C. This process as carried out continuously is as folloas: The material is placed in the digestor I and a solvent, such as gasolene, is admitted from a solvent tank 11 to submerge the charge which is then heated. Steam is then admitted to thc upper part of the digestor t o expel the solvent through pipes 16 and 17 back to the tank 11. The residue in the digestor I
is then removed and a fresh supply of material placed in thc digestor and subjected to the action of the previously used solvent. This solvent is again forced back into the tank 1 1 and a supply of fresh solvent from tank IO admitted. This after a heating operation is forced back into tank IO. Steam is then passed through the residue which is then ready for removal. The solvent is distilled from time to time in the still 21 to separate the resin.
the heating coil, a pipe, e, leads to a water-cooling coil, f,situated in a water chamber. The hydrocarbons condensed in the coil f pass into a vessel, h, and the uncondensed vapors pass through a pipe, k, provided mith amercurygage, I , into another condensing chamber, m , from which further hydrocarbons are collected in the vessel n. The vacuum is produced by means of the vacuum and compressing pump o, and the vapors passing the pump pass through a cooling coil, p , immersed in brine. Isoprene is condensed in the coil p , and is collected in the chamber 7 . From the chamber r , the uncondensed vapor passes by the pipe s to the chamber t , immersed in brine. 4 blow-off valve, v , is provided from the top of this last condensing chamber. PROCESS O F TREATING NATURAL GAS. U. S. Patent No. 1,023,783, to Isaac N. Knapp, of Ardmore, Pa., Assignor to The United Gas Improvement Company of Philadelphia, Pa. The purpose of the process is to make acetylene from natural gas. Natural gas containing approximately g z per cent. to 97 per cent. of methane or marsh gas, CH,, is passed through a bed of coke or coal from which air is excluded and which is maintained a t a heat higher than t h a t of ordinary or atmospheric combustion. The marsh gas is converted into acetylene, C,H,, the reaction being represented by the equation CH,+3C = zC,H,.
