Appeal No. 97-3640
Application No. 08/406,272
1. Rejection of claims 1-5 under 35 U.S.C. § 102(b) as anticipated by Skraba
Skraba describes a process for steam cracking an alkane hydrocarbon stream wherein alkane
1, 2 feeding through a vaporizer 3 has steam 4 added thereto and the admixture is then fed into a
cracking furnace 8 where the feed is heated to ethylene production conditions. The furnace effluent 11
containing ethylene, propylene, carbon dioxide, steam and other materials is passed to prequench zone
12 to decrease the temperature of the effluent 11 so coking and deposition is minimized in subsequent
equipment. The prequenched effluent is passed to transfer line exchanger 16 from which the cooled
mass is passed to final quench 18 and then to aqueous caustic washer 23 (for CO removal). From
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caustic washer 23 the mass is passed to fractionation 26 for recovery of wanted products. (col. 2, line
67 to col. 3, line 42; col. 4, lines 22-25, "Furnace Effluent (11)"; and, the Figure)
The appellant argues (a) steam is added to a saturated hydrocarbon, e.g., ethane/propane, not
to an olefin, at line 4; (b) adding steam to a gas which is not an olefin and is to be thermally cracked at
1500E to 1600E F is not what is being claimed; and, (c) water is added to the transfer line exchanger
16, not to the olefin. Since Skraba excludes the step (1) of the claimed invention of adding water to a
fluid to form a water-containing fluid comprising at least one C -C olefin and CO and step (2) that2 6 2
said water-containing fluid is contacted with..., Skraba cannot anticipate claims 1-5 (Br. page 7).
The examiner states "the position of the final rejection is: that what transpires in cracking furnace
8 of Skraba, constitutes exactly a step of 'adding water to an olefin-containing fluid to form a water-
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