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 .
Applicant’s election without traverse of Group I, claims 11-17 in the reply filed on November 21, 2026 is acknowledged.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 16 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The phrase “processed by a CO2 activation by H2 from an H2O electrolysis via a reverse water gas shift reaction” creates a convoluted chain of dependency. It is unclear if the “via” refers to the “activation” the “H2” or the processing of the syngas. This “chaining” of three different chemical concepts into a single descriptive phrase leaves the actual sequence of the operations--and thus the metes and bounds of the claim—open to multiple conflicting interpretations. Suggested revised claim 16 as follow:
The method of claim 11, further comprising generating H2 via electrolysis and contacting H2 with CO2 in a reverse water gas shift reactor to provide the synthesis gas.
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 11-17 are rejected under 35 U.S.C. 103 as being unpatentable over Weedon et al (US 2019/0084833 A1) in view of De Sarkar et al (US 2022/0081289).
Applicants’ claimed invention is directed to a method for converting CO2 into chemical energy carriers and products, wherein the method comprises or consists of:(a) provision of a synthesis gas comprising H2, CO and CO2, the synthesis gas having a CO2 content of at least 5 vol.%,(b) feeding the synthesis gas to a Fischer-Tropsch synthesis, and converting the synthesis gas to a Fischer-Tropsch synthesis product comprising at least the following fractions: (i) a fuel fraction, (ii) a wax fraction, (iii) a gaseous by-product phase, (iv) an aqueous phase, (c1) optionally, hydrogenation of the Fischer-Tropsch synthesis product obtained in (b) with addition of hydrogen, (c2) multi-stage separation of the Fischer-Tropsch synthesis product obtained in (b) or of the product obtained in (c1),and separation of fractions (i), (ii) and (iv), (d) methanation of the gaseous by-products in fraction (iii) with addition of H2, (e) optionally, further processing of fractions (i), (ii), (iv).
Weedon teaches a method for producing hydrocarbon compounds. The method comprising: producing a syngas by introducing a fuel stream comprising a reformable fuel into a reforming system (steam reformer, autothermal reformer, cold plasma reformer and/or internal-reforming fuel cell), and wherein the syngas comprises H2, CO and CO2, and has a ratio of [H2]/[CO] of about 1.4 to about 2.5; producing a decarbonated and dehydrated syngas from the syngas having a ratio of [CO2]/[CO+CO2] of no higher than 0.6; performing a Fischer-Tropsch synthesis on the decarbonated and dehydrated syngas in the presence of a cobalt- or iron-based Fischer-Tropsch catalyst, said Fischer-Tropsch catalyst comprising pellets of trilobe, cylindrical, hollow cylinder or spherical construction with diameter about 0.5 mm to about 3.0 mm and aspect ratio of 1 to 3.5, to produce a product stream comprising the hydrocarbon compounds; and recycling aqueous products and/or tail gas. See abstract.
Weedon teaches the hydrocarbon compounds comprise liquid fuel and wax, and the method may further comprise: separating the wax from other gaseous products of the Fischer-Tropsch synthesis (e.g. but without limitation, in a hot trap); cooling the other gaseous products (e.g. but without limitation, in a cold trap) to condense out the aqueous products comprising water and liquid fuel from the tail gas; and separating the liquid fuel from remaining aqueous products [0022]. Table 6 discloses the composition of the syngas and the product made.
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The primary difference between Weedon and De Sarkar lies in their focus within the integrated Fischer-Tropsch and methanation process. While Weedon provides the high CO2 syngas and the four fraction FT separation, De Sarkar provided the electrolysis, Reverse water gas shift reaction (RWGSR), hydrogenation of Fischer Tropsch and methanation.
De Sarkar teaches converting the syngas stream in a synthesis stage into at least a product stream and, optionally, a hydrocarbon-containing off-gas stream; feeding at least a portion of said hydrocarbon-containing off-gas stream to the syngas stage as a fourth feed comprising hydrocarbons, upstream of said ATR section and preferably between said methanation section and/or reverse water gas shift (rWGS) section, and said ATR section, the synthesis stage may be a Fischer-Tropsch (F-T) stage arranged to convert said syngas stream into at least a hydrocarbon product stream and a hydrocarbon-containing off-gas stream in the form of an F-T tail gas stream. [0145] an electrolyser may be located upstream the syngas stage and the method may further comprise conversion of water or steam into at least a hydrogen-containing stream and an oxygen-containing stream [0142]-[0145].
De Sarkar teaches a tail gas from an FT synthesis stage will normally not be added to a methanation unit but fed directly to the ATR section. If excess tail gas from the FT synthesis stage is available, this may be hydrogenated and fed to the methanation section [0068].
De Sarkar teaches the synthesis stage is a Fischer-Tropsch synthesis (F-T) stage. The F-T stage comprises Fischer-Tropsch (F-T) synthesis section where syngas from syngas stage is first converted to at least a raw product comprising hydrocarbons and a hydrocarbon containing off-gas stream in form of an F-T tail gas stream followed by hydroprocessing (using H2 to refine and upgrade hydrocarbons) and hydrocracking section where said raw product is converted to at least one or more hydrocarbon product streams. The ratio between long chain hydrocarbons and olefins in the raw product from the F-T synthesis section depends on the type of catalyst, reaction temperature etc. that are used in the process [0096].
De Sarkar teaches the water or steam which is fed to the electrolyser is obtained as condensate or steam from one or more units or stages in the plant [0145].
Since De Sarkar already teaches the production of methane (NG) from tail gas (paragraphs 0143-0145) then feeding methane into a natural gas (NG) network is a predictable use of prior art elements according to their stablished functions.
It would have been obvious to a person of ordinary skill in the art, prior to the effective filing date of the claimed invention to combine the teachings of Weedon and De Sarkar because both references are directed toward the common goal of maximizing carbon conversion within a synthetic fuel production, while Weedon provide the foundation Fischer-Tropsch process for processing CO2 rich syngas into specific fuel, wax, and aqueous fractions, it inherently leaves behind a gaseous “tail gas” byproduct; De Sarkar specifically addresses this deficiency by teaching the methanation of such gaseous streams to provide synthetic natural gas. A skill artisan would be motivated to integrate De Sarkar’s use of water electrolysis and RWGSR to activate carbon dioxide into the syngas feed required by Weedon, as this combination yields the predictable technical result of a closed loop power to liquids. This integration is driven by the industry standard pursuit of process economy and carbon efficiency, thereby rendering the claimed multi-step synthesis a routine assembly of known chemical engineering unit.
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/JAFAR F PARSA/ Primary Examiner, Art Unit 1692