Patented Sept. 12, 1933 1926,642 UNITED STATES PATENT of FICE 1926,642 PROCESS OF OBTAINING REACTION PRODUCTS OF RETENE Charles O. Young and George H. Reid, South Charleston, W. Wa, assignors to Carbide & Carbon Chemicals. Corporation, a corporation of New York No Drawing. Application December 2, 1930 Serial No. 502,005 8 Claims. (C. 260-06) The invention is an improved process of mak plied in any desired manner, for example the ap ing reaction products of ketene (CH2=C-O). In paratus for quenching the hot vapors may take general, the process of our invention comprises the form of a packed tower scrubber, spray-scrub thermally decomposing a substance which will ber or any other suitable means for rapidly cool form ketene, and rapidly cooling the hot gaseous ing the hot vapors in intimate contact with the 80 products of this pyrolysis in intimate contact with abSOrbing medium. a reacting absorbing medium. The absorption or quenching means may be The principal object of the invention is to pro operated at ordinary temperatures, and in such Wide a method of making ketene and reaction a case the resultant liquid will contain the reac 0 products thereof which will result in the forma tion product of ketene and the absorbing medium, 65 tion of a maximum amount of valuable product excess absorbing medium and condensed un and which will minimize losses of the ketene changed acetone. The liquid may be circulated formed. until Sufficiently reacted with ketene and then sep In the manufacture of ketene by the pyrolysis arated from the diluent acetone, or it may be oth 15 of organic compounds, e.g., acetone, two primary erwise treated for the separation or recovery of O difficulties in Securing useful quantities of ketene its several constituents. - have been encountered, namely; ketene decom The process may be successfully practiced by poses easily at its formation temperature, and at Operating the quenching device at a temperature ordinary temperatures it polymerizes rapidly in which will not cause the acetone to condense, but 20 both the pure state and in inert solvents, yielding which will permit the unconverted acetone to 75 products from which it cannot easily be regen pass off as a gas where it may be easily recov erated. - ered. This procedure is preferable in certain The first of the above enumerated objections instances, inasmuch as it avoids dilution of the has been largely overcome in the prior art by im absorbing medium with acetone. 25 proved technique in manipulating the pyrolysis. The invention is not limited to the formation 80 The second, although equally as important, has of reaction products from ketene produced in the received little or no attention. In all cases where manner set forth, but includes the utilization, by it has been proposed to utilize ketene in an ab the method described herein, of ketene which is sorption system to form reaction products thereof, produced by any equivalent means. 30 the hot vapors from the pyrolytic operation are We claim: N. 85. condensed to remove acetOne or other unchanged 1. A process of obtaining reaction products of starting material, and the ketene is then passed ketene which comprises immediately passing sub - to an absorption train. In this way a large stances formed by pyrolysis of organic substances amount of ketene dissolves in the condensed sub which yield decomposition products including ke 35 stance and rapidly polymerizes into a dark tarry tene, into a quenching stream of an absorbing 90 mass. Further losses may be caused by polymeri medium which is reactive with ketene. zation in the conduit which conveys the ketene to 2. A process of obtaining reaction products of the absorption train. ketene which comprises thermally decomposing Our improved process obviates these prior difi Organic compounds which yield Substances in 95 40. culties, hence, its advantages will be apparent. cluding ketene and rapidly cooling the products We prefer to practice our invention as follows: of pyrolysis in intimate contact with an absorb Ketene is formed by the pyrolysis of acetone in ing medium which is reactive with ketene. a converter and the vapors from this converter 3. A process of obtaining reaction products of are immediately quenched in a stream of the ab ketene which comprises immediately passing the OO 45 sorbing medium with which it is desired to have substances formed by the pyrolysis of acetone the ketene react. It is primarily essential to the into a quenching stream of an absorbing medium process that the time elapsing between the re which is reactive with ketene. moval of the hot vapors from the converter and 4. A process of obtaining reaction products of their contact with the quenching medium beVex ketene, which, comprises pyrolytically treating 105 50 tremely short. acetone and rapidly cooling the products obtained The quenching medium may be any reagent thereby in intimate contact with an absorbing with which it is desired to have the ketene react, medium which is reactive with ketene. for example antline, acetic acid, ethylene glycol 5. A process of obtaining the acetate of ethyl monoethyl ether, alcohol or water may be used. ene glycol monoethyl ether which comprises im 55 This quenching or absorbing medium may be sup mediately passing the substances formed by the O 2 i,926,642 pyrolysis of acetone into a quenching stream of stances formed by the pyrolysis of acetone into ethylene glycol monoethyl ether. a quenching stream of acetic acid. 6. A process of obtaining the acetate of ethyl 8. A process of obtaining acetic anhydride ene glycol monoethyl ether which comprises in which comprises immediately passing the Sub mediately passing the substances formed by the stances formed by the pyrolysis of acetone into pyrolysis of acetOne into a quenching stream of a quenching stream of acetic acid at a tempera ethylene glycol monoethyl ether at a tempera ture such as to cause any unchanged acetone in ture Such that any unchanged acetone in the the mixture to remain in the gaseous state. mixture will remain in the gaseous state. 0 7. A process of obtaining acetic anhydride CHARLES O. YOUNG. 85 which comprises immediately passing the sub GEORGE B, RED.

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