DETAILED ACTION
Response to Amendment
The Examiner acknowledges the Applicant’s response on January 2, 2026 containing remarks and amendments to the claims. The amendments are sufficient to overcome the previous 112 rejection but are not sufficient to overcome the prior art.
A Final Rejection follows.
Final Rejection
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-9 and 11-15 are rejected under 35 U.S.C. 103 as being unpatentable over Valladares Barrocas et al. US Patent 4,232,179 in view of Kuechler et al. US Patent 7,678,953.
Regarding claim 1, Valladares Barrocas teaches a dehydration process of converting ethanol into ethylene (column 10 lines 15-20) using a heat carrying fluid comprising steam (column 3 lines 27-31).
Valladares Barrocas teaches that the steam may be supplied by an external source (column 3 line 31) but does not explicitly teach the steam is sourced from an oligomerization process.
Kuechler teaches an oligomerization process where steam is supplied to the reactor 30 overhead through heat exchanger 26 preceding the oligomerization reactor 26 (column 18 lines 38-40). A side stream of steam is recovered through line 34 and may be used in further applications (column 18 lines 43-54).
It would have been obvious to one having ordinary skill in the art at the time of filing to use the steam generated from the oligomerization of Kuechler as the carrying fluid for the dehydration reaction in Vallardes Barrocas because the combination would provide an integrated process converting an alcohol into an oligomer. Kuechler teaches the feed for their oligomerization may derive from the conversion of an oxygenate (column 6 lines 66-67), thus suggesting integration with an ethanol dehydration process. Therefore, one having ordinary skill in the art would find it conventional to combine the Kuechler oligomerization process with Valladares Barrocas and expect a reasonable amount of success. One would further be motivated to use the steam generated from Kuechler’s oligomerization because it is expected that the steam recovered from the oligomerization process would be nearly pure steam as the heavier hydrocarbons and impurities would be easily condensed out. Thus, it is obvious to one having ordinary skill in the art to use the steam from Kuechler in the dehydration process of Valladares Barrocas to provide a renewable and efficient means for the dehydration carrier fluid.
Regarding claim 2, Kuechler implies that water is obtained as a byproduct from a process (Example 5) and may be treated and used as the source for steam. The water is submitted to heat exchanger 26, connected to the oligomerization reactor 28, where it is heated to steam (column 18 line 52). As noted in the combination above, it is obvious to use the steam generated here as the carrying fluid in Valladares Barrocas’s dehydration process.
Regarding claim 3, a portion of boiling water is carried down through the heat exchanger 26 (column 18 lines 46-47).
Regarding claim 4, Kuechler teaches a hydrogenation step in Example 4. Since hydrogenation is strongly exothermic, one would expect steam to be generated from the carrying fluid. Thus, the recovered steam would be an obvious source to use for the dehydration process in Valladares Barrocas. Valladares Barrocas teaches that the steam may be supplied by an external source (column 3 line 31), thus a byproduct steam from hydrogenation would be an obvious source.
Regarding claim 5, the combination teaches an integrated dehydration and oligomerization process where steam heat exchange step occurs on the effluent before oligomerization. Kuechler teaches the olefin recycle (analogous to the oligomerization feedstream and dehydration effluent) should be cooled to no greater than 182 ⁰C (column 7 line 23). Thus, since this range overlaps with the claimed range, a prima facie case of obviousness exists.
Regarding claim 6, Valladares Barrocas teaches that the ratio between steam and feed is in the range of 0.2:1 to 20:1, thus overlapping with the claimed range of about 0.3 to about 0.5 wt/wt.
Regarding claims 7 and 8, Kuechler appears to teach the heat exchanger accepts a mixed feed, however one would expect that the heat exchanger would function the same on a sole steam/water feed absent any evidence to the contrary. Further repeating a heat exchange step is considered obvious to one having ordinary skill in the art. One would be motivated to do so in order to meet the needed temperature for oligomerization.
Regarding claims 9, Kuechler teaches that the oligomerization reactor and heat exchanger can be repeated in series (column 3 line 66). Thus, Kuechler suggests an arrangement where a plurality of steam generators 26 are used to make steam.
Regarding claims 11-15, Kuechler teaches that the oligomerization reactor and heat exchanger can be repeated in series (column 3 line 66). Thus, Kuechler suggests an arrangement where a plurality of steam generators 26 are used to make steam and function as an intercooler steam generator that removes heat from the oligomerization effluent obtained from the prior reactor and/or bed before passing to the next reactor/bed.
Claims 16-20 are rejected under 35 U.S.C. 103 as being unpatentable over Valladares Barrocas et al. US Patent 4,232,179, evidenced by Valladares Barrocas et al. US Patent 4,396,789 (hereinafter Barrocas ‘789) in view of Kuechler et al. US Patent 7,678,953.
Regarding claims 16, 17, and 20 Valladares Barrocas teaches a dehydration process of converting ethanol into ethylene (column 10 lines 15-20) using a heat carrying fluid comprising steam (column 3 lines 27-31).
Valladares Barrocas teaches that the products are recovered (column 8 line 59). Barrocas ‘789 teaches that cooling a dehydration effluent to condense out water is well known in the art (column 3 lines 55-68).
Valladares Barrocas teaches that the steam may be supplied by an external source (column 3 line 31) but does not explicitly teach the steam is sourced from an oligomerization process.
Kuechler teaches an oligomerization process where steam and water are supplied to the reactor 30 overhead through heat exchanger 26 preceding the oligomerization reactor 26 (column 18 lines 38-40). A side stream of steam is recovered through line 34 and may be used in further applications (column 18 lines 43-54).
It would have been obvious to one having ordinary skill in the art at the time of filing to use the steam generated from the oligomerization of Kuechler as the carrying fluid for the dehydration reaction in Vallardes Barrocas because the combination would provide an integrated process converting an alcohol into an oligomer. Kuechler teaches the feed for their oligomerization may derive from the conversion of an oxygenate (column 6 lines 66-67), thus suggesting integration with an ethanol dehydration process. Therefore, one having ordinary skill in the art would find it conventional to combine the Kuechler oligomerization process with Valladares Barrocas and expect a reasonable amount of success. One would further be motivated to use the steam generated from Kuechler’s oligomerization because it is expected that the steam recovered from the oligomerization process would be nearly pure steam as the heavier hydrocarbons and impurities would be easily condensed out. Thus, it is obvious to one having ordinary skill in the art to use the steam from Kuechler in the dehydration process of Valladares Barrocas to provide a renewable and efficient means for the dehydration carrier fluid.
Therefore, the combination of Kuechler and Valladares Barrocas teach:
1. Adding steam as the carrying fluid to a dehydration feed (Valladares Barrocas column 3 line 31)
2. Dehydrating the feedstream to produce a dehydration effluent (Valladares Barrocas column 10 lines 15-20);
3. Removing the product from the byproducts by cooling thus recovering water (Valladares Barrocas column 8 line 59 and Barrocas ‘789 column 3 lines 55-68); and
4. Producing steam from the separated water/steam (column 18 lines 38-40)
Regarding claim 18, Kuechler implies that water is obtained as a byproduct from a process (Example 5) and may be treated and used as the source for steam. The water is submitted to heat exchanger 26, connected to the oligomerization reactor 28, where it is heated to steam (column 18 line 52). As noted in the combination above, it is obvious to use the steam generated here as the carrying fluid in Valladares Barrocas’s dehydration process.
Regarding claim 19, Valladares Barrocas and Kuechler teach the combination above. Kuechler further teaches that water recovered is combined with an olefin stream in mixing drum 22 and sent to heat exchanger 26 to generate steam (column 18 lines 33-37).
Response to Arguments
Applicant's arguments filed January 2, 2026 have been fully considered but they are not persuasive.
Applicant argues in the Remarks that:
Barrocas does not teach adding steam to a feed stream. Instead, Valladares Barrocas teaches the indirect heating of the feed. Since the steam is not being added to the feed of Valladares Barrocas, the combination of a teaching of sending steam from an oligomerization reactor such as that taught by Kuechler even when combined would not result in the claimed invention as set forth in claim 1 where the steam from an oligomerization reactor is sent directly to the feed. Even if the steam from Kuechler could be used for any purpose, there is no suggestion that the steam could be used in a dehydration reaction.
In response the Examiner respectfully disagrees. In column 3 lines 24-33 of Valladares Barrocas, “..the necessary heat to maintain the temperature of the catalyst bed at levels compatible with the desired conversion is supplied by the simultaneous introduction of the feed and the sensible heat carrying fluid. The heat carrying fluids mostly desired for the present process may be selected from: part of the effluent from the reactor used as recycle stream; steam supplied by an external source...” (emphasis added by the Examiner). Thus, Valladares Barrocas does teach that an amount of steam is added to the feed to the dehydration reactor.
The Examiner does acknowledge that the source of this steam carrier fluid is not explicitly from an oligomerization reaction. However, Valladares Barrocas does explicitly state that the steam may be supplied from an external source. Steam is recovered from an oligomerization process in Kuechler and is used for other applications. “The steam generated in the heat exchanger reactor 26 may be used, for example, to provide heat in fractionation tower reboilers or to make electricity in turbogenerators.” (Kuechler column 18 lines 50-54).
Thus, Kuechler teaches the recovery of steam generated in an oligomerization reactor system and further teaches that such steam may be used for additional plant applications. Valladares Barrocas teaches that steam supplied from an external source may be used as a heat-sensible carrying stream introduced simultaneously with the feed to the dehydration reactor. Thus, one having ordinary skill in the art would find it obvious to use a recovered steam stream from Kuechler’s oligomerization as the heat-sensible carrying stream in Valladares Barrocas because doing so represents a predictable and conventional integrated process step for improving efficiency.
In response to the Applicant’s argument that there is no suggestion that the steam in Kuechler can be used for dehydration processes, the Examiner respectfully disagrees does not find the argument persuasive. The examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In this case, Kuechler teaches that steam generated in the oligomerization section may be recovered and used for additional applications, thereby identifying a reusable steam source within the oligomerization process. Valladares Barrocas teaches introducing steam from an external source as a sensible heat-carrying stream in an ethanol dehydration reaction. Therefore, it would have been obvious to one having ordinary skill in the art to utilize the recoverable steam stream in Kuechler as the external steam source of Valladares Barrocas as a predictable process-integration measure for providing process heat.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/SHARON PREGLER/Primary Examiner, Art Unit 1772