DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 4/8/2026 has been entered.
Claims 1-17, 21-27 and 28 (new) are pending. Claims 18-20 are canceled.
Previous rejection of the claims under 35 USC 103 are modified in view of the amendments but maintained. Previous rejections of the claims under 35 USC 112 are withdrawn.
Response to Arguments
Applicant's arguments filed 3/4/2026 with respect to the rejection under 35 U.S.C. § 103 as being unpatentable over Noe et al. (WO Publication No. 2012/135111) have been fully considered but they are not persuasive.
Applicant’s Argument, Reply p. 9-11
Applicant argues the art of record, Noe, fails to teach or suggest "obtaining a cleansed first lean-solvent stream by (A3-a) contacting the first lean-solvent stream with a first cleansing bed and a second cleansing bed, wherein the first cleansing bed comprises activated carbon that provides a first surface to adsorb the heavy components, and wherein the second cleansing bed comprises an ion exchange resin, alumina, or any combination thereof that provides a second surface to adsorb one or more impurities formed based on degradation of the polar solvent” as required by claim 1, and similar limitation presented in claim 15 with reversed order of beds. Reply, pages 9-10.
Applicant acknowledges that Noe teaches in par. [0019] sending the lean stream “to one or more first solvent-purification vessels in vessel 33 containing a solid adsorbent, which adsorbs contaminants from the solvent to yield a purified solvent”. Applicant also points to the teaching of Noe that the adsorbent may include alumina, ion exchange resin, and activated carbons listed among a limited number of exemplified adsorbents. Reply, page 10 (citing Noe at par. [0019].
Applicant then argues, that Noe teaches only a single adsorbent selected from one of the listed adsorbents. Reply, page 10-11. Applicant argues “[i]nasmuch as Noe teaches an adsorbent, Noe does not specifically teach or suggest a second or secondary cleansing bed, much less specific surfaces of the cleansing beds configured to remove different components (e.g., heavy components, impurities formed based on degradation of the polar solvent.)”. Reply, page 10 (original emphasis). Applicant further explains the specific configuration provides a non-polar surface of activated carbon and a polar surface of ion-exchange resin or alumina for preferential adsorption of different impurities. Reply, page 11.
Response
Applicant’s argument has been considered but is not persuasive. With respect to the presence of a secondary cleansing bed, Noe teaches “one or more first solvent-purification vessels in vessel 33 containing a solid adsorbent, which adsorbs contaminants from the solvent to yield a purified solvent”. Noe, par. [0019]. One or more vessels containing a solid adsorbent anticipates two vessels containing a solid adsorbent.
With respect to one of the one or more beds containing activated carbon and one of the one or more beds containing ion-exchange resin, alumina, or a combination, such configuration would have been obvious in view of the teaching of Noe. Noe explicitly states “[a] variety of adsorbents are suitable for contaminant removal in the solvent-purification vessels. Polymeric adsorbents such as those used for oil recovery are suitable adsorbents. Other suitable sorbents include alumina, silica, silica-alumina, zeolitic and non-zeolitic molecular sieves and activated carbon”, par. [0022], or “wherein the adsorbent is selected from the group comprising alumina, silica-alumina, clay, a zeolitic molecular sieve and an ion-exchange resin,” claim 6. Thus, Noe exemplifies nine adsorbents including activated carbon and alumina. Selection of any of the taught adsorbents for each of the one or more vessels falls within the teaching of the art.
Alternatively, it would have been obvious to one of ordinary skill in the art to select two adsorbents from the exemplified list because each is taught for the same purpose. This flows from the rationale that it is obvious to combine compositions for the same purpose which are taught to be useful for the same purpose. It is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose... [T]he idea of combining them flows logically from their having been individually taught in the prior art." In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980).
Further, Noe teaches “[a] contaminated lean solvent stream containing a measurable amount of heavy hydrocarbons, including aromatics heavier than the product and decomposed materials, is withdrawn from a bottom portion of the solvent-recovery column through conduit 27.” Noe at [0018]. With respect to the decomposed impurities, Noe provides a list of potential polar solvents, such as sulfolane (0020). Noe explains degradation of sulfolane produces products of sulfur dioxide and oxygen-containing organic compounds which are removed from the solvent using the process of the invention (0021). Thus, Noe recognizes the need for and the actual removal of both heavy hydrocarbons and impurities from decomposed polar solvent from the lean solvent stream.
Noe teaches the use of two (one or more) vessels. Noe teaches the selection of ion-exchange resin, alumina, and activated carbon as suitable adsorbents. Noe teaches the removal of the same impurities claimed. Thus, applicant’s arguments are not persuasive and Noe renders obvious the rejection of claim 1.
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.
Claim(s) 1-11, 14-17, 21-23 and 25-28 is/are rejected under 35 U.S.C. 103 as being unpatentable over Noe (WO 2012/135111).
With respect to claims 1 and 15, Noe teaches a distillation-extraction process for extracting aromatic hydrocarbons from a mixture feed comprising aromatic hydrocarbons and non-aromatic hydrocarbons (0012), the process comprising:
feeding the mixture into an extraction column (0015);
providing a solvent stream comprising a polar solvent and a heavy component (0015; 0018 feeding lean solvent with heavy hydrocarbons back to the extraction column);
removing the rich solvent and passing the rich solvent to a solvent recovery column 20 for separating aromatic concentrate from lean solvent (0016); and
cleansing the lean solvent in one or more vessels comprising adsorbents to obtaining a cleansed solvent stream (0019 “one or more first solvent-purification vessels in vessel 33” and “one or more [second solvent-purification] vessel[s] 36”; see 0016-0019). The range of one or more includes two vessels. “A variety of adsorbents are suitable for contaminant removal in the solvent-purification vessels. Polymeric adsorbents such as those used for oil recovery are suitable adsorbents. Other suitable sorbents include alumina, silica, silica-alumina, zeolitic and non-zeolitic molecular sieves and activated carbon,” Par. 0022, as well as clay or ion exchange resin, claim 6. “The purified organic solvent fluid flowing through the fluid flow pathway may be re-circulated such that it undergoes multiple passes through the solvent-purification vessels.” Par. 0023. The adsorbents remove heavy hydrocarbons and decomposition material from the used solvent to produce a lean solvent. Par. 0020-0021.
At least a portion of the cleansed solvent stream is passed back into the extraction column (0019) with a portion of rich, uncleaned solvent.
With respect to the selection of sorbent for the two (one or more) lean-solvent adsorbent beds, Noe teaches using one or more vessels containing adsorbent beds, which includes 2; teaches a list of sorbents that may be used in the process, including those claimed; teaches removing the same two impurities; and teaches wherein the solvent may be recycled through the beds to achieve additional removal, indicating one bed alone may not provide adequate purification. Therefore, before the filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to utilize two vessels in the process of Noe (anticipated by the range 1 or more) having activated carbon sorbent in one vessel and alumina or ion-exchange resin in the other because Noe exemplifies a limited number of sorbents useful for use in the vessels to remove impurities from the solvent, both compositions are known for the same purpose and are placed in series to achieve that same purpose.
With respect to the content of polar solvent in the solvent and heavy hydrocarbon stream, Noe teaches utilizing a mixture of fresh solvent, with purified solvent, with wash solvent containing contaminants from the regenerated train. Therefore, before the filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to optimize the amount of heavy hydrocarbon in the lean-solvent fed to the column to maintain the desired extraction of the feedstream while optimizing cost of purifying used solvents and providing fresh solvent.
With respect to claims 2 and 16, Noe teaches removing heavy hydrocarbons in a series of solvent recovery steps to produce the lean solvent, which will contain less than the saturation concentration of heavy components.
With respect to claim 3, Noe teaches using one or more beds of adsorbent, including activated carbon and/or alumina (0022), ion exchange (claim 6), among others.
With respect to claim 4, Noe teaches removing contaminants from the solvent using a series of distillation followed by of one or more adsorbent columns. Noe teaches recycling the lean solvent through the adsorbent beds such that it may undergo multiple passes (0023). Noe teaches mixing a portion of rich solvent with a portion of the cleansed solvent prior to use (0019), showing that the concentration of the final lean solvent will be tailored. It would have been obvious to one of ordinary skill in the art at the time of filing to optimize solvent recovery steps to achieve optimal hydrocarbon content of the solvent balancing cost of purifying and effectiveness of the recycled lean solvent during the extraction step.
With respect to claims 5 and 17, Noe teaches using one or more beds of adsorbent, including activated carbon and/or alumina (0022), ion exchange (claim 6), among others.
Noe is silent regarding the specific surface area of the activated carbon. It would have been obvious to one of ordinary skill in the art at the time of filing utilize an activated carbon having a specific surface area capable of adsorbing contaminants from the polar solvent.
With respect to claim 6, Noe teaches wherein the column is an extractive distillation column (0015).
With respect to claim 7, Noe teaches wherein the solvent may include e.g. sulfolane (0020).
With respect to claims 8 and 21, Noe teaches wherein the purification zone is typically operated at 0-100C (0023), which includes both columns where two is selected for as the one or more columns of adsorbents.
With respect to claims 9-10 and 22, Noe teaches feeding to the extraction column a part of lean solvent purified for heavy hydrocarbon adsorption with a part of the lean solvent which bypasses the purification step and is sent directly to extractive distillation (0019). Thus, the two solvents recovered from the columns and used as recycled solvents are derived from a common stream (see figure 1, stream 30). With respect to the portion of each stream utilized as the solvent, it would have been within the skill of one in the art at the time of filing to optimize the ratio of the first recovered stream containing contaminants to the second recovered stream containing less contaminants, to maintain a recycled solvent of sufficient quality while optimizing the overall process efficiency and economics.
With respect to claims 11 and 23, Noe teaches recovering a rich solvent stream containing solvent, aromatic hydrocarbons, and heavy hydrocarbons form the bottom section of the extractive-distillation column (0016); separating the bottoms stream in a solvent-recovery column into an overhead containing aromatics substantially free of solvents and non-aromatic hydrocarbons and a bottoms stream depleted in aromatics; and using the bottoms stream depleted in aromatics to generate the lean solvent for use in the extraction column or feed to the adsorption column (0016-0017).
With respect to claim 14 and 25, Noe is silent regarding interrupting or reducing supply of feed and maintaining the temperature in the column near the temperature prior to interruption. However, Noe teaches operating an extractive distillation column which requires a certain temperature to maintain fractionation. It would have been obvious to one of ordinary skill in the art at the time of filing to maintain the temperature of the column to allow continued operation of the column as well as to maintain stable fractionation/vapor-liquid separation, to maintain product quality, or to maintain a stabilized column for when the disruption ceases.
With respect to claims 26 and 27, Noe teaches utilizing more than one adsorbent vessel and provides an explicit list of adsorbents capable of removing the contaminants. It would have been obvious to select one or multiple of said adsorbents in series in any order, to achieve their stated purpose as discussed above.
With respect to claim 28, Noe teaches multiple sorbents. Where two separate sorbents are selected, they necessarily have two separate surfaces.
Claim(s) 12, 13, and 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Noe as applied to claims 1-11, 14-17, 21-23 and 25-28 above, and further in view of Lee (US 9,440,947).
With respect to claims 12, 13 and 24, Noe teaches the limitations above, including solvent extraction of the bottoms stream to generate a third lean stream and utilizing steam in the solvent-recovery column. Noe is silent regarding deriving a fourth lean stream from the third lean stream and regenerating the fourth lean stream using a steam stripping regenerator and/or vacuum regenerating to obtain a regenerative lean-solvent stream and a bottoms heavy stream, and feeding the regenerated stream into one or more of the solvent recovery column and the extraction column. Lee teaches wherein the process of removing aromatics from a hydrocarbon using solvent may occur in an extractive distillation column or in a liquid-liquid extraction column, as known in the art. The rich solvent is recovered and separated in an solvent recovery column. Stripping steam maybe injected into the SRC to assist in the removal of aromatic HCs from the solvent. Lee teaches that “[i]n order to minimize the bottom temperature of SRC 302, receiver 309 is connected to a vacuum source to generate sub-atmospheric conditions in SRC 302. A lean solvent stream containing measurable amounts of heavy HCs is withdrawn from the bottom of SRC 302 through line 14.” It would have been obvious to one of ordinary skill in the art at the time of filing to utilize the liquid-liquid extraction column of Lee the process of Noe to do no more than obtain predictable results and to utilize steam stripping and/or vacuum in the solvent recovery column of Noe as taught in Lee to improve recovery of aromatics from the polar solvent as taught by Lee.
Conclusion
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/BRANDI M DOYLE/Examiner, Art Unit 1771
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