Appeal No. 97-3640
Application No. 08/406,272
and of exceptional results (Br. pages 10-11), having concluded that the examiner has not established a
prima facie case of obviousness from the teachings of the prior art we do not reach this rebuttal
evidence.
The rejection is reversed.
3. Rejection of claims 23-25 under 35 U.S.C. § 103(a) over McKernan in view of Jones
McKernan removes carbon dioxide from liquid and gaseous olefin-containing fluids by passing
the fluid through a bed of solid particulate absorbent material comprising sodium hydroxide and/or
potassium hydroxide; alumina and/or zinc oxide; lime; and, optionally copper II oxide (abstract), e.g.,
prior to catalysis to avoid poisoning or otherwise adversely affecting the catalyst employed (page 1,
paragraph two). Preferably, the composition contains up to 10 wt. % NaOH and 40-97% Ca(OH) ,
2
i.e., soda lime (Table page 3). According to the examiner, McKernan differs from claim 23 in failing to
state literally that the olefin fluid also comprises water (Ans. page 6, paragraph one).
Jones discloses
...in order to make suitable grade ethylene for the production of certain grades of
polyethylene, small concentrations of CO (of approximately 10-25 ppm) in the olefin
2
feed have to be reduced to less than 1ppm. One present practice uses a caustic pellet
absorber bed. Two major problems associated with this procedure are: (i) only about
3 percent of the NaOH present in the bed is converted to Na CO (via 2NaOH + CO2 3 2
W Na CO + H O); and (ii) after the outer coat of the pellet is converted to the2 3 2
carbonate, the water generated can cause particle agglomeration and bridging which in
turn causes channeling and finally complete solidification of the bed. The latter is a
particularly difficult problem because the bed contents at times have had to be removed
manually. An aqueous caustic solution has been proposed as an alternative. One
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