DETAILED ACTION
Election/Restriction
Restriction to one of the following inventions is required under 35 U.S.C. 121:
I. Claims 1-4, drawn to a method for removing H2S from reservoir fluids, classified in C10L 3/103.
II. Claims 5-14, drawn to a system for removing H2S from reservoir fluids, classified in B01J 19/123.
The inventions are independent or distinct, each from the other because:
Inventions I and II are related as process and apparatus for its practice. The inventions are distinct if it can be shown that either: (1) the process as claimed can be practiced by another and materially different apparatus or by hand, or (2) the apparatus as claimed can be used to practice another and materially different process. (MPEP § 806.05(e)). In this case the process can be carried out in another and materially different apparatus, such as a system having a storage vessel which applies the UV to the sour gas.
Restriction for examination purposes as indicated is proper because all the inventions listed in this action are independent or distinct for the reasons given above and there would be a serious search and/or examination burden if restriction were not required because one or more of the following reasons apply:
Separate classification thereof: This shows that each invention has attained recognition in the art as a separate subject for inventive effort, and also a separate field of search. Patents need not be cited to show separate classification.
A different field of search: Where it is necessary to search for one of the inventions in a manner that is not likely to result in finding art pertinent to the other invention(s) (e.g., searching different classes/subclasses or electronic resources, or employing different search queries, a different field of search is shown, even though the two are classified together. The indicated different field of search must in fact be pertinent to the type of subject matter covered by the claims. Patents need not be cited to show different fields of search.
Applicant is advised that the reply to this requirement to be complete must include (i) an election of an invention to be examined even though the requirement may be traversed (37 CFR 1.143) and (ii) identification of the claims encompassing the elected invention.
The election of an invention may be made with or without traverse. To reserve a right to petition, the election must be made with traverse. If the reply does not distinctly and specifically point out supposed errors in the restriction requirement, the election shall be treated as an election without traverse. Traversal must be presented at the time of election in order to be considered timely. Failure to timely traverse the requirement will result in the loss of right to petition under 37 CFR 1.144. If claims are added after the election, applicant must indicate which of these claims are readable upon the elected invention.
Should applicant traverse on the ground that the inventions are not patentably distinct, applicant should submit evidence or identify such evidence now of record showing the inventions to be obvious variants or clearly admit on the record that this is the case. In either instance, if the examiner finds one of the inventions unpatentable over the prior art, the evidence or admission may be used in a rejection under 35 U.S.C. 103 or pre-AIA 35 U.S.C. 103(a) of the other invention.
During a telephone conversation with Sahana Annadorai on 8 July 2026 a provisional election was made with traverse to prosecute the invention of group I, claims 1-4. Affirmation of this election must be made by applicant in replying to this Office action. Claims 5-14 are withdrawn from further consideration by the examiner, 37 CFR 1.142(b), as being drawn to a non-elected invention.
The examiner has required restriction between product or apparatus claims and process claims. Where applicant elects claims directed to the product/apparatus, and all product/apparatus claims are subsequently found allowable, withdrawn process claims that include all the limitations of the allowable product/apparatus claims should be considered for rejoinder. All claims directed to a nonelected process invention must include all the limitations of an allowable product/apparatus claim for that process invention to be rejoined.
In the event of rejoinder, the requirement for restriction between the product/apparatus claims and the rejoined process claims will be withdrawn, and the rejoined process claims will be fully examined for patentability in accordance with 37 CFR 1.104. Thus, to be allowable, the rejoined claims must meet all criteria for patentability including the requirements of 35 U.S.C. 101, 102, 103 and 112. Until all claims to the elected product/apparatus are found allowable, an otherwise proper restriction requirement between product/apparatus claims and process claims may be maintained. Withdrawn process claims that are not commensurate in scope with an allowable product/apparatus claim will not be rejoined. See MPEP § 821.04. Additionally, in order for rejoinder to occur, applicant is advised that the process claims should be amended during prosecution to require the limitations of the product/apparatus claims. Failure to do so may result in no rejoinder. Further, note that the prohibition against double patenting rejections of 35 U.S.C. 121 does not apply where the restriction requirement is withdrawn by the examiner before the patent issues. See MPEP § 804.01.
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.
Claims 1-4 are 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 term “trace” in claim 1 (“trace H2S”) is a relative term which renders the claim indefinite. The term “trace” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. It is unclear from the context of the claim and corresponding specification what concentration of H2S would be within the scope of “trace.”
Further regarding claim 1, the claim encompasses an embodiment wherein the sour gas stream, separated from a produced reservoir fluid, comprises one or more alkenes. The source of the alkene(s) is unclear, given that alkenes (olefins) are not naturally present in produced gases (refer to Speight for evidence – section 2.2; Table 2.1; p. 55). It is unclear whether, in the embodiment of the sour gas stream comprising alkene(s), a step of adding alkene(s) is required.
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 2 is rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Claim 2 specifies that the organosulfur compound (produced in step b) is a mercaptan. According to the specification, the office understands that mercaptan is produced when the reactant is an alkene, not when the reactant is an alkane. Given that claim 1 encompasses alkane(s) or alkene(s) (or both), in the embodiment wherein the gas stream comprises alkane(s), but not alkene(s), a mercaptan would not be produced. Therefore, claim 2 fails to limit the embodiment of claim 1 to require the presence of an alkene in order for the process to proceed as claimed, i.e., production of a mercaptan.
Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
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.
Claims 1-4 are rejected under 35 U.S.C. 103 as being unpatentable over Barnes et al (US 2016/0200592) in view of Baltrusaitis et al (“H2S mediated thermal and photochemical methane activation”).
Regarding claims 1 and 2, Barnes is directed to treatment of a mixed production fluid comprising separating a produced reservoir fluid 102 (in separator 104) into a produced water stream 110, a crude oil stream 108, and a sour gas stream 106 (natural gas comprising acid gas components up to 8% molar concentration). The sour gas is then treated to remove acid-gas components, including H2S, to produce sweet gas. The sweet gas then enters a natural gas sales line (i.e., is distributed as claimed) (see Fig. 1; [0002]; [0036]; [0038]-[0042]; [0058]-[0059]). The sour gas stream of Barnes inherently comprises at least an alkane (natural gas is predominantly methane) (also see Table 2).
Barnes differs from the instant claims in that it does not disclose treatment entailing exposing the sour gas stream to sufficient UV to convert the H2S to an organosulfur compound.
Baltrusaitis discusses the need to discover techniques for addressing natural gas resources with high content of H2S. Baltrusaitis proposes a method for activating the sour gas to form a mixture of sulfur-containing intermediates, including CH3SH and CH3SCH3 (organosulfur compounds) and an energy carrier, such as H2. Sour gas is exposed to UV in order for methane therein to react with hydrogen sulfide to produce the organosulfur compound(s). Baltrusaitis discloses that the process can be driven photolytically at low temperatures, with enhanced controllability over process conditions and is CO2 neutral (see Abstract; p. 3, equation (7) and discussion which follows disclosing irradiation at 200 nm light, i.e., ultraviolet).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to modify the process of Barnes by including a step for treating the sour gas with UV in order to convert H2S into organosulfur compound(s) by reaction with hydrocarbons in the sour gas stream, as suggested by Baltrusaitis, given that such treatment is shown to have enhanced controllability, is CO2 neutral, and produces hydrogen which is a useful fuel product.
With respect to the concentration of H2S in the sweet gas, the process resulting from the combination of Barnes and Baltrusaitis is reasonably expected to produce a sweet gas stream having a concentration of H2S (zero or trace) as claimed. Furthermore, given that the goal is removal of as much hydrogen sulfide as possible, a person of ordinary skill in the art would optimize the conditions of the sour gas treatment which results in a sweet gas stream having an acceptable level of hydrogen sulfide (i.e., maximum removal thereof down to a concentration as close to zero as possible).
Regarding claim 3, Barnes discloses gas treatment including use of a scavenger comprising methyldiethanolamine (see [0058]).
Regarding claim 4, Barnes discloses gas treatment including use of an adsorbent (see [0058], pressure-swing adsorption).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Chauvin et al (US 11,161,810).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RENEE ROBINSON whose telephone number is (571)270-7371. The examiner can normally be reached Monday - Thursday 8:00a-5:00p and Friday 8:00a-2:00p.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, In Suk Bullock can be reached at (571)272-5954. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Renee Robinson/Primary Examiner, Art Unit 1772
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