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 .
Status of the Claims
Claims 1-6 are pending.
Response to Arguments
Applicant’s arguments filed 31 July 2025 have been fully considered but they are not persuasive.
Applicant’s argue that Horton and Wang do not disclose the limitations as recited in the previously presented claims. These arguments have been considered but are not persuasive for the reasons set forth in the response to arguments below.
In response to applicant’s arguments throughout the remarks filed on 31 July 2025, specifically on pages 3-4, that “the Horton et al. '549 reference is not directed to the standalone purification of acetic acid” and “is directed to processes for producing a highly purified water stream in the process of producing ethanol from acetic acid (claim 1 of Horton et al. '549)”. ““The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain.” In re Heck, 699 F.2d 1331, 1332-33, 216 USPQ 1038, 1039 (Fed. Cir. 1983) (quoting In re Lemelson, 397 F.2d 1006, 1009, 158 USPQ 275, 277 (CCPA 1968)). A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments. Merck & Co. v. Biocraft Labs., Inc. 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir. 1989), cert. denied, 493 U.S. 975 (1989).” see MPEP 2123.
In this case, instant base claim 1 states “producing purified acetic acid from a mixed solution containing acetic acid, an organic solvent, and water”. Horton’s method for the production, separation, and purification of ethanol and water also teaches a process for the separation of acetic acid from a mixed solution containing acetic acid, organic solvents, and water, see Horton Tables 1 and 2. The mixed solution is sent to an acid separation distillation column to obtain a solution comprising primarily about 100 wt.% acetic acid, see Horton, Table 3; Paras. [0053];[0057]. As stated on page 4 of the remarks filed on 31 July 2025, “[i]n Example 3 of Horton et al. '549, the residue from the first distillation column (line 116) contains approximately 98.2 wt.% acetic acid, 3.7 wt.% water, and 0.04 wt.% ethanol.” Since the method of Horton is not limited to the production, separation, and purification of ethanol and water, and is relevant as prior art for all it contains, Horton specifically teaches the base claim 1 limitation of “producing purified acetic acid from a mixed solution containing acetic acid, an organic solvent, and water”. For the reasons indicated above, applicants above arguments are not persuasive.
In response to applicant’s arguments throughout the remarks filed on 31 July 2025, specifically on page 4, that “Horton et al. '549 reference is primarily focused on removing trace organics and impurities from the water stream (paragraphs [0006] and [0010]) and does not aim to produce glacial or commercially marketable acetic acid”. It is noted that “glacial or commercially marketable acetic acid” are not recited in the rejected claim(s) and are therefore not given patentable weight.
As stated on page 4 of the remarks filed on 31 July 2025, “Horton et al. '549 expressly state, “[s]ome or all of the residue may be returned and/or recycled back to reaction zone 101 via line 116” (paragraph [0057]), confirming that the acetic acid stream is intended for internal reuse.” Horton, Para. [0057] teaches the recycle of the acetic acid “may improve efficiencies of the process while reducing byproducts” and Para. [0088] teaches the process is a commercial industrial process. Therefore, the acetic acid of Horton is used in a commercial process. For the reasons indicated above, applicants above arguments are not persuasive.
In response to applicant’s arguments throughout the remarks filed on 31 July 2025, specifically on pages 5-6, that “Horton et al. '549 do not disclose or suggest a process for the external purification of acetic acid”, “[t]he acetic acid stream in Horton et al. '549 is already sufficiently pure for internal recycling, and Horton et al. '549 provide no disclosure or motivation to further purify the acetic acid stream”. It is noted that “external purification of acetic acid” is not recited in the rejected claim(s) and is therefore not given patentable weight.
Horton teaches the recycle acetic acid stream 116 from the acid separation column 107 is sent to a vaporizer 110 to further purify the acetic acid stream removing “the amount of heavies” in the acetic acid stream, see Horton, Paras. [0050];[0053];[0057]; Fig. 1. Therefore, Horton teaches the further purification of the acetic acid from the acid separation column. As stated above, Horton teaches purification of heavies from acetic acid by vaporization and only some or all of the acetic acid may be recycled, i.e., may be implies may not be recycled, see Horton, Para. [0057]. Horton, Para. [0043] also teaches “acetic acid in vapor form may be taken directly as crude product from the flash vessel of a methanol carbonylation unit”, i.e., an external purification. For the reasons indicated above, applicants above arguments are not persuasive.
In response to applicant’s arguments throughout the remarks filed on 31 July 2025, specifically on pages 4-6, that “Wang et al. '668 relate to a fundamentally different technical goal (i.e., production of glacial acetic acid)” and “[o]ne of ordinary skill in the art would have no proper reason, rationale, or motivation to combine Horton et al. '549 and Wang et al. '668”, the test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art, see In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). As stated above Horton teaches the internal and external further purification of acetic acid by vaporization, and the acetic acid may not be recycled. Wang teaches the purification of acetic acid by pervaporation membrane separation, see Wang, Paras. [0005]-[0006];[0070].
The rationale to support a conclusion that the claim would have been obvious is that “a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely that product [was] not of innovation but of ordinary skill and common sense”, see MPEP 2143 I.E. Since both Horton and Wang teach vaporization separation of acetic acid, a person of ordinary skill in the art has good reason to purify any product and/or residue stream containing acetic acid by pursuing the known options within their technical grasp, such as by membrane vaporization as taught by Wang, for the benefit of removing water and trace components from a high-concentration water/acetic acid mixture with greater efficiency and cost savings in order to obtain a glacial acetic acid product, see Wang, Paras. [0004]-[0006] and MPEP 2141. For the reasons indicated above, applicants above arguments are not persuasive.
In response to applicant’s argument on page 6 of the remarks filed on 31 July 2025 that “the claimed invention exhibits particularly remarkable effects that are neither disclosed nor suggested in Horton et al. '549 or Wang et al. '668. Specifically, the claimed invention achieves a significant energy-saving effect by greatly reducing the energetic load required for water separation in the distillation step”, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious, see Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985). As stated above, since both Horton and Wang teach vaporization separation of acetic acid, a person of ordinary skill in the art has good reason to purify any product and/or residue stream containing acetic acid by pursuing the known options within their technical grasp, such as by membrane vaporization as taught by Wang, for the benefit of removing water and trace components from a high-concentration water/acetic acid mixture with greater efficiency and cost savings in order to obtain a glacial acetic acid product, see Wang, Paras. [0004]-[0006] and MPEP 2141. For the reasons indicated above, applicants above arguments are not persuasive.
In response to applicant’s arguments on pages 5-6 of the remarks filed on 31 July 2025 that the examiner’s conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant’s disclosure, such a reconstruction is proper, see In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). For all of the reasons indicated above, applicants argument regarding hindsight reasoning is not persuasive.
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.
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.
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.
Claims 1-6 are rejected under 35 U.S.C. 103 as being unpatentable over Horton et al. (US20110190549, hereinafter Horton) in view of Wang et al. (CN102285668, published 21 December 2011, hereinafter Wang, see machine translation).
Horton teaches the claim 1 limitations of a method for producing purified acetic acid by acid separation as a column 107 residue containing 60 to 100 wt.% acetic acid, see Table 3, Paras. [0053];[0057];[0063]-[0065], and Fig. 1, specifically Paras. [0096]-[0097], and Table 10, Example 3, from a crude ethanol product composition containing acetic acid, ethyl acetate, ethanol, and water, see Table 1 and Para. [0048], that has been sent to a flasher 106 to produce a liquid feed composition containing acetic acid, ethyl acetate, ethanol, and water, see Tables 2, 10, Paras. [0053];[0096], and Fig. 1, meeting a method for producing purified acetic acid from a mixed solution containing acetic acid, an organic solvent, and water in claim 1;
The Table 2 liquid feed composition 115 is separated by distillation in column 107 to obtain the Table 3 residue liquid 116 of 60 to 100 wt.% acetic acid, less than 30 wt.% water, and less than 1 wt.% ethanol, specifically 98.2 wt.% acetic acid, 3.7 wt.% water, 0.04 wt.% ethanol and no detectable levels of ethyl acetate in the residue of Table 10, the top distillate 117 containing 20 to 75 wt.% ethanol, less than 2 wt.% acetic acid, and less than 60 wt.% ethyl acetate is condensed to liquid, see Paras. [0057]-[0062];[0097]-[0098], Tables 2, 3, 10, and Fig. 1, meeting distilling the mixed solution and separating the mixed solution into a purified liquid rich in acetic acid and a separated liquid rich in an organic solvent, wherein the purified liquid has a water concentration of 4 wt.% or less in claim 1;
where the purification/separation apparatus may contain additional reactors, flashers, condensers, heating elements, and other components known to those in the art, such as various condensers, pumps, compressors, reboilers, drums, valves, connectors, separation vessels, etc., normally employed in carrying out chemical processes, see Paras. [0060]-[0061].
Horton teaches the claim 2 limitations of wherein the purified liquid has an ethyl acetate concentration of non-detectable, see Paras. [0064];[0097], and Table 10, meeting wherein the purified liquid has an ethyl acetate concentration of equal to or less than a detection limit in claim 2.
Horton teaches the claim 3 limitations of wherein the purified liquid has an organic solvent concentration of 0.04 wt.% ethanol and no detectable levels of ethyl acetate or other organic solvents in the residue, see Table 10, and the acetic acid residue solution of Table 3 comprises 100% acetic acid, see Table 3, meeting wherein the purified liquid has an organic solvent concentration of equal to or less than a detection limit in claim 3.
Horton teaches the claim 6 limitations of wherein the mixed solution is derived from a liquid discharged during a process such as via methanol carbonylation, acetaldehyde oxidation, ethylene oxidation, oxidative fermentation, and anaerobic fermentation, see Para. [0039].
Horton does not teach the claim 1 limitations of supplying the purified liquid to an inlet side of a separation membrane while in a liquid state; and
separating the water from the purified liquid by the separation membrane.
Horton does not specifically teach the claim 2 and claim 3 limitations of as measured by gas chromatography.
Horton does not teach the claim 4 limitations of wherein the separation is performed by bringing the purified liquid into contact with the separation membrane under reduced pressure.
Horton does not teach the claim 5 limitations of wherein the separation membrane is one or more zeolite separation membrane(s) selected from the group consisting of A-type, FAU-type, CHA-type, MFI-type, MOR-type, and DDR-type zeolite separation membranes.
Horton does not specifically teach the claim 6 limitations of wherein the mixed solution is derived from a liquid discharged during a process of producing cellulose acetate.
Wang relates to zeolite separation membranes for the purification of acetic acid from aqueous solutions separating water from the acetic acid at a performance of 100% leading to 0% water in the purified acetic acid liquid, see Abstract and Paras. [0004]-[0008];[0070].
Wang teaches supplying an acetic acid aqueous solution via inlet (d) to a zeolite separation membrane (e), such as ZSM-5 zeolite membrane which is a MFI molecular sieve membrane and MOR zeolite membranes, under vacuum/reduced pressure conditions, such as 400 Pa, to dehydrate the acetic acid by removing water, where the composition of the raw material solution and the permeate are analyzed using an HP6890+ gas chromatograph, and the raw material acetic acid solution is derived from the production of cellulose acetate, see Paras. [0004];[0007];[0029];[0043];[0064]-[0066], and Fig. 3, meeting the limitations of:
supplying the purified liquid to an inlet side of a separation membrane while in a liquid state; and separating the water from the purified liquid by the separation membrane in claim 1;
meeting the limitations of as measured by gas chromatography in claim 2;
meeting the limitations of wherein the separation is performed by bringing the purified liquid into contact with the separation membrane under reduced pressure in claim 4;
meeting the limitations of wherein the separation membrane is one or more zeolite separation membrane(s) selected from the group consisting of MFI-type and MOR-type separation membranes in claim 5,
meeting the limitations of wherein the mixed solution is derived from a liquid discharged during a process of producing cellulose acetate in claim 6.
In reference to the above claims, it would have been obvious to one of ordinary
skill in the art, before the effective filing date of the claimed invention, to have modified
the separation process of Horton to further purify the acetic acid solution with the separation membrane teaching of Wang for the benefit of removing water and trace components from a high-concentration water/acetic acid mixture with greater efficiency and cost savings in order to obtain a glacial acetic acid product, see Wang, Paras. [0004]-[0006], with a reasonable predictability of success.
By applying “routine optimization” to select the optimal separation apparatus known in the art and separation techniques, as taught by Wang, one of ordinary skill in the art would have been motivated to make these modifications because Wang provides a finite number of identified, predictable solutions, and a person of ordinary skill in the art has good reason to efficiently produce a purified acetic acid by pursuing the known options within their technical grasp, such as through use of zeolite membrane separation, for the benefit of removing water and trace components from a high-concentration water/acetic acid mixture with greater efficiency and cost savings, see Wang, Paras. [0004]-[0006]. See also MPEP 2141.
As stated in Sakraida v. Ag Pro, Inc., 425 U.S. 273, 189 USPQ 449, reh’g denied, 426 U.S. 955 (1976), “[w]hen a work is available in one field of endeavor, design incentives and other market forces can prompt variations of it, either in the same field or a different one. If a person of ordinary skill can implement a predictable variation, § 103 likely bars its patentability. For the same reason, if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious unless its actual application is beyond his or her skill”. See MPEP 2141.
In addition, selection of a known material, such as a zeolite separation membrane, based on its suitability for its intended use supported a prima facie obviousness determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945). See MPEP 2144.07.
Further, “[t]he normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges”, such as the % organic solvent in the acetic acid residue, “is the optimum combination of percentages.” In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969). See MPEP 2144.05.
Conclusion
No claims are allowed.
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 Y. Lynnette Kelly-O'Neill whose telephone number is (571)270-3456. The examiner can normally be reached Monday-Thursday, 8 a.m. - 6 p.m., EST, with Flex Time.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Scarlett Yen-Ye Goon can be reached at (571) 270-5241. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/YO/Examiner, Art Unit 1692
/RENEE CLAYTOR/Supervisory Patent Examiner, Art Unit 1691