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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 06/09/2026 has been entered.
Status of the Claims
The amendment filed on 06/09/2026 has been entered. Claims 1 and 13 have been amended and claims 2-4 and 18 have been canceled. Claims 1, 5-17 and 19-20 are currently pending, claims 13-17 and 19-20 are withdrawn, and claims 1 and 5-12 are under examination.
Withdrawn Rejection
Claim 1 has been amended by narrowing the lower stream
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Patent application publication number US2018/0118651A1 (US’651; cited in IDS 11/29/2022) fails to teach every newly recited limitations and thus the 102(a)(1) rejection has been withdrawn.
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.
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 and 5-12 are rejected under 35 U.S.C. 103 as being unpatentable over Patent application publication number US2018/0118651A1 (US’651; cited in IDS 11/29/2022).
Regarding claim 1, US’651 teaches in Figs. 1 and 3, a process for separating acetaldehyde (PRC) from a first mixture 44, 43b comprising acetaldehyde, methyl iodide and water, the process comprising the steps of:
feeding the first mixture 44, 43b to a first location of a distillation column 5, wherein the first mixture has a methanol mass composition that is less than the difference based on mass between methyl iodide and water (Example 6);
distilling the first mixture into a second mixture and a lower stream 52, the second mixture being at least one stream selected from the group consisting of an overhead stream 53 and a sidedraw stream 63 being withdrawn higher than that of the first location where stream 44, 43b is fed; and
withdrawing the lower stream 52 from a second location lower than the first location;
wherein the first mixture is separated into the second mixture and lower stream without the supply of additional methanol; and
wherein the second mixture is enriched in the at least one PRC ([0121]).
The reference further exemplifies in Tables 9-13 that the lower stream 52 from a second location lower than the first location satisfies all the following conditions (i) to (iii).
Condition (i):
Tables 9-13 list specific components present in the lower stream 52, i.e. DME (dimethyl ether), AD (acetaldehyde), MeI (methyl iodide), MeOH (methanol), MA (methyl acetate), water, and AC (acetic acid). The total wt% of these components in the lower stream 52 amounts to 100 wt%, and thus acetal is not present in the lower stream 52, or is 0 wt%;
Condition (ii):
Tables 9-13 satisfies the condition because MeOH and AD are present in the lower stream 52 in view of the indicated wt% values, and thus the total acetal mass composition in the lower stream 52, 0 wt%, is lower than combined wt% of MeOH and AD in the lower stream 52.
Condition (iii):
The total mass composition in the lower stream 52 in Tables 9-13, 0 wt%, is less than the w% of MeOH in the first mixture 44.
Furthermore, the amount of dimethyl ether in the lower stream according to Tables 9-13 is 0 wt%.
Regarding claim 5, the combined mass composition of MeOH and AD in the lower stream 52 of for condition (ii) in Tables 9-10 is 0.0446, 0.082, 0.408 and 0.984 wt%, respectively.
Regarding claim 6, the MeOH mass composition for condition (iii) in the first mixture 44 of Tables 9-13 is 0.07, 0.08, 0.09, 0.99 and 0.99 wt%, respectively.
Regarding claims 7-8, in Example 6 of US’651, the first mixture comprises 82.6 wt% MeI (methyl iodide), 1840 ppm (0.184 wt%) AD (acetaldehyde, PRC), 0.69 wt% water and 0.07 wt% methanol ([0235]).
Regarding claim 9, US’651 discloses throughout the document distilling the first mixture using just water as an extractant.
Regarding claim 10, the reference teaches the flow rate of the extractant relative to the first mixture ranging from 0.0001/100 to 100/100 ([0021]).
Regarding claim 11, US’651 teaches the composition of the second mixture comprising methyl idodide, PRC and water at the amounts as instantly claimed ([0121]). Furthermore, since the reference teaches every limitation of the separation steps as instantly claimed, it is anticipated for the composition of the second mixture to be the same as instantly claimed.
Regarding claim 12, US’651 teaches biphasically separating the second mixture into an aqueous phase and an organic phase ([0138]-[0140]).
Regarding claim 1, as indicated above, the reference teaches that in condition (i) the total acetal mass composition in the lower stream 52 is 0 wt% and the amount of dimethyl ether in the lower stream is 0 wt%, but fails to teach a mass composition of acetal from 0.001 wt% to 0.02 wt% and wherein the lower stream comprises from 0.001 wt% to 0.8 wt% dimethyl ether.
However, the instant specification describes the problems associated with the presence of acetal during the purification of PRCs in [0018] and [0022]:
High amounts of total acetal reduce the ability to remove PRCs, resulting in ineffective processing. In one embodiment, to reduce the total acetal, the feed stream to the distillation column has a methanol mass composition that is maintained (controlled) to be less than the difference based on mass between the one or more C1-C12 alkyl iodides (in particular methyl iodide) and water in the stream. Reducing the total amount of acetal (and/or hemiacetals) may further enrich the mixture in PRC. As used herein the terms “mass composition” or “concentration” refers to the mass fraction of substance to the total mass and is generally expressed in % by mass or wt %, unless indicated otherwise.
The present inventors have found that acetals formation proceeds to react one of the PRCs to form high boiling point components that tend to concentrate in (transfer to) the lower stream.
The lower stream is a return stream, which refers to a stream that is returned to the process, such as returning to the reactor or an upstream distillation column or other suitable vessel. This undesirably introduces the acetal and/or hemiacetal throughout the process leading to a buildup of impurities that can deteriorate the quality of the acetic acid product.
Thus, based on the above disclosure, it is understood the need to remove the acetals from PRCs due to their unwanted reactive properties with the PRCs.
The instant specification further describes the approaches used to reduce the total acetal mass composition as described in [0019]-[0020]:
In another embodiment, to reduce the total acetal the process may involve separating PRCs from the one or more C1-C12 alkyl iodides without an additional supply of methanol to the distillation column.
In another embodiment, to reduce the total acetal the process may involve separating PRCs from the one or more C1-C12 alkyl iodides in the presence of acetic acid, water, methyl acetate and/or methanol.
By conducting the above methods in reducing the acetal mass composition, Applicant achieved a lower stream with a total amount of acetal that satisfies condition (i) is described in [0023]
A total acetal amount in the lower stream is not more than 0.02 wt %, e.g., not more than 0.018 wt %, not more than 0.015 wt % or not more than 0.01 wt %. In one embodiment, to remove acetals formed in the column, the lower stream may have a lower amount that is not less than 0.0001 wt %, e.g., not less than 0.0005 wt % or not less than 0.001 wt %.
With respect to the amount of dimethyl ether in the lower stream 52, the instant specification describes in [0135]
Other components in the lower stream 52 may contain methyl acetate and dimethyl ether. Methyl acetate mass composition in the lower stream 52 may be from 5 to 60 wt%, e.g., 10 to 50 wt%, or 10 to 35 wt%, and dimethyl ether mass composition may be from 0 to 1.2 wt%, e.g., from 0.001 to 0.8 wt%, or from 0.005 to 0.5 wt%.
US’651 does not explicitly recognize the problem associated with acetal in the lower stream and in the purification process of PRC overall. However, it recognizes in [002] that a permanganate reducing compound test (permanganate time) detects extremely small amounts of impurities even if the extremely small amounts are difficult to determine quantitatively by current advanced instrumental analysis. The reference describes the same methods that are described in the instant specification to reduce the acetal formation. For example, the method of US’651 involves:
separating PRC from methyl iodide without an additional supply of methanol to the distillation column (see Figs. 1 and 3),
separating PRC from methyl iodide in the presence of acetic acid, water, methyl acetate and methanol (see line 43 and 44).
The lower stream 52 of US’651 contains minimal impurities, including 0 wt% of acetal and dimethyl ether. The Applicant does not provide the criticality of the instantly claimed total acetal mass composition in the lower stream from 0.001 wt% to 0.02 wt% and dimethyl ether from 0.001 wt% to 0.8 wt% over the 0 wt% of each in US’651.
Furthermore, in view of the instant specification [0129], side-draw 53 that is enriched in PRC contains dimethyl ether in amounts ranging from 0 to 1.2 wt%. The same is observed in US’651 (Tables 9-13), in which the overhead and side-draw streams 53 and 63 contain enriched AD (PRC or acetaldehyde) and dimethyl ether in an amount as described in the specification. In other words, the separated PRC described in the specification appears to have the same impurities as the one described in US’651.
Thus, absent any evidence of criticality and unexpected results, the claimed method is prima facie obvious over the disclosure of US’651.
It would thus have been prima facie obvious to a skilled artisan before the effective filing date of the instant invention to conduct a process for separating at least one permanganate reducing compound (PRC) from a first mixture comprising the at least one PRC, one or more CI-C12 alkyl iodides and water, the process comprising the steps of: feeding the first mixture to a first location of a distillation column, wherein the first mixture has a methanol mass composition that is less than the difference based on mass between the one or more CI-C12 alkyl iodides and water; distilling the first mixture into a second mixture and a lower stream, the second mixture being at least one stream selected from the group consisting of an overhead stream and a sidedraw stream being withdrawn higher than that of the first location; and withdrawing the lower stream from a second location lower than the first location when the lower stream satisfies of the following conditions (i) to (iii): (i) a total acetal mass composition in the lower stream is from 0.001 wt% to 0.02 wt%; (ii) a total acetal mass composition in the lower stream is less than a combined mass composition of methanol and acetaldehyde in the lower stream; and (iii) a total acetal mass composition in the lower stream is less than the methanol mass composition in the first mixture; wherein the lower stream comprises from 0.001 wt % to 0.8 wt % dimethyl ether; wherein the first mixture is separated into the second mixture and lower stream without the supply of additional methanol; and wherein the second mixture is enriched in the at least one PRC in view of the teachings of US’651.
Conclusion
Claims 1 and 5-12 are rejected and no claims are allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MEDHANIT W BAHTA whose telephone number is (571)270-7658. The examiner can normally be reached Monday-Friday 8am-5pm.
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/MEDHANIT W BAHTA/Primary Examiner, Art Unit 1692
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