DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 103
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim 1-5 are rejected under 35 U.S.C. 103 as being unpatentable over Hiles et al. (US 5,254,758) in view of Huff et al. (US 5,837,128).
Regarding claims 1-5, the reference Hiles et al. discloses a fixed bed reaction vessel (9, 15) used for hydrogenation of aldehydes to alcohols (see col. 3, lines 27-44; col. 5, lines 66 to col. 6, line 42; Figure), wherein the vessel comprises an inlet (10, 14) and an outlet (11, 17) and has an empty volume (i.e., before a fresh charge of catalyst), wherein the vessel is partially filled with catalyst pellets wherein a majority of the catalyst pellets comprise a catalytic metal, wherein when the vessel is partially filled with a first set of catalyst pellets, each having an aspect ratio and shape (see col. 6, lines 23-31), the vessel exhibits a pressure drop increase rate which is the rate at which the pressure drop increases across the vessel over time, wherein the first set of catalyst pellets has a void fraction (see col. 6, lines 4-23).
The reference Hiles et al., however, does not specifically disclose a process for reducing the rate of pressure drop increase in the vessel, comprising: (a) replacing the first set of catalyst pellets with a second set of catalyst pellets, wherein the second set of catalyst pellets have a higher average aspect ratio than the first set of catalyst pellets, a different shape than the first set of catalyst pellets, or a combination thereof, wherein a void fraction of the second set of catalyst pellets is greater than the void fraction of the first set of catalyst pellets; wherein a pressure drop rate increase of the vessel partially filled with the second set of catalyst pellets is less than a pressure drop rate increase of the vessel partially filled with the first set of catalyst pellets when operated under substantially similar conditions.
The reference Huff et al. teaches a method for optimizing the pressure drop in the catalytic conversion of a feed in a bed of catalyst particles in a vertically arranged reactor by grading the catalyst particles within the bed by pressure drop (see Abstract; col. 2, lines 38-45, col. 3, lines 8-42). The reference Huff et al. teaches that a convenient method to effectively grade the catalyst particles within the bed includes partially filling an empty volume of a reaction vessel with a first set of catalyst pellets, each having an aspect ratio and shape, wherein the first set of catalyst pellets has a void fraction; and partially filling the reaction vessel with a second set of catalyst pellets, wherein the second set of catalyst pellets have a higher average aspect ratio than the first set of catalyst pellets, a different shape than the first set of catalyst pellets, or a combination thereof, wherein a void fraction of the second set of catalyst pellets is greater than the void fraction of the first set of catalyst pellets; wherein a pressure drop rate increase of the vessel partially filled with the second set of catalyst pellets is less than a pressure drop rate increase of the vessel partially filled with the first set of catalyst pellets when operated under substantially similar conditions (see col. 4, lines 9-46; col. 5, lines 17-62).
Accordingly, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention, seeking to reduce pressure drop rate increase in the reaction vessel of Hiles et al., to replace at least a portion of the first set of catalyst pellets with a second set of catalyst pellets as taught by Huff et al., and predictably arrived at the instantly claimed process through a mere routine experimentation and optimization based on the teachings of Huff et al., because, as taught by Huff et al. (see Abstract; col. 2, lines 38-45, col. 4, lines 40-46), the disclosed method advantageously provides for an efficient technique for establishing graded catalyst bed in the vessel to optimally reduce the rate of pressure drop increase in the vessel.
Response to Arguments
Applicant's arguments filed on 28 October 2025 have been fully considered but they are not persuasive.
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
Applicant argues:
While it is known that the use of particles with larger void fractions will result in lower pressure drops, there is no teaching or suggestion that larger particles will exhibit a slower rate of change than smaller particles (that is, there is nothing that suggests that the use of larger catalyst particles will result in the pressure drop increasing more slowly than when a set of catalyst pellets having a higher void fraction is used). (see Remarks, page 5).
The examiner respectfully disagrees. The reference Huff et al. teaches that in a vertically arranged reactor containing a bed of catalyst particles having the same shape, shortest dimension (such as diameter), and composition, a reduction in the rate of pressure drop build-up across the reactor can be attained by grading the catalyst particles within the bed by pressure drop such that catalyst particles within the catalyst bed have progressively higher pressure drops in the direction of feed flow (see col. 2, lines 24-45; col. 3, lines 8-31). The reference Huff et al. teaches that a convenient method to effectively grade the catalyst particles is by exchanging, for example, a large portion (such as 90%) of the catalyst bed layer composed of catalyst particles having a small particle size (such as particles having a relative average length-to-diameter ratio of 1.0) with a larger size catalyst particles (such as particles having a relative average length-to-diameter ratio of 1.8) so as to minimize the rate of pressure drop build-up across the reactor due to a reduction in the layer of catalyst particles having a relatively smaller particle size (see col. 2, lines 24-27; col. 5, line 17 to col. 6, line 4). Further, in view of the teachings of the reference Huff et al. (see col. 1, lines 18-61; col. 4, lines 59-62; col. 5, lines 17-62), one of ordinary skill in the art would expect that replacing a bed of catalyst particles having a smaller particle size (and therefore, a low void fraction) with a bed of catalyst particles having a relatively larger particle size (and therefore, larger void fraction) would permit a reduction in the rate of pressure drop build-up across the catalyst bed when operated under substantially similar conditions. This is because, as evidenced in the background section of the reference Huff et al. (see col. 1, lines 18-61), compare to the void spaces available between the relatively small catalyst particles in the bed of catalyst particles having a smaller particle size, the bed of catalyst particles having a relatively larger particle size provides more capacity for accommodation of fine particles in the void spaces between that relatively larger catalyst particles before the development of excessive flow restrictions in the catalyst bed due to a buildup of the fine particles in the catalyst bed over time. Furthermore, the reference Hiles et al. recognizes that an increase in the rate of pressure drop build-up across the catalyst bed is typically expected to occur over the life of the catalyst charge in the reactor vessel, which eventually leads to an increase in the running cost of the plant to an economically unacceptable level, and thus, requiring replacement of the catalyst charge with a fresh set of catalyst charge (see col. 2, lines 5-10; col. 6, lines 4-22).
Accordingly, the examiner maintains the position that it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention, seeking to reduce the pressure drop rate increase in the reaction vessel of Hiles et al., to replace at least a portion of the first set of catalyst pellets of Hiles et al. with a second set of catalyst pellets as taught by Huff et al., and predictably arrived at the instantly claimed process through a mere routine experimentation and optimization based on the teachings of Huff et al., because, as taught by Huff et al. (see Abstract; col. 2, lines 38-45, col. 4, lines 40-46), the disclosed method of Huff et al. advantageously provides for an efficient technique for establishing graded catalyst bed in the vessel to optimally reduce the rate of pressure drop increase in the vessel.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Lessanework T Seifu whose telephone number is (571)270-3153. The examiner can normally be reached M-T 9:00 am - 6:30 pm; F 9:00 am - 1:00 pm.
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/LESSANEWORK SEIFU/Primary Examiner, Art Unit 1774