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 .
Election/Restrictions
Claims 13-20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 6/4/26.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 1 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Harkness (US Pat.: 5211923).
Harkness describes a process for generating hydrogen and elemental sulfur from a hydrogen sulfide waste (abstract). The process feeds a hydrogen sulfide stream into a plasma reactor (col. 3, lines 35-37). The system powers the plasma reactor (col. 3, lines 40-43). This can be considered a step of “igniting a plasma in the plasma reactor”. The stream may also contain CO2 (col. 3, lines 39-40, 45-46). The plasma dissociates H2S into H2 and sulfur plus impurities such as COS, CS2, SO2 and other compounds (col. 3, lines 42-45). The produced hydrogen and sulfur are processed using a scrubber that condenses the sulfur into a liquid stream for removal from the bottom of the scrubber by line 26 (col. 3, lines 50-53). The hydrogen is then removed col. 3, lines 57-58).
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.
Claim(s) 2, 3, 4, 8, 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Harkness.
Harkness teaches that either at or before a catalytic reduction unit used for a shift conversion, water is added to the stream (col. 4, lines 3-8) to react CO to CO2 with H2 (col. 4, lines 6-7). Although Harkness does not specifically teach that the reaction of H2 and Co forms CO2 and H2O, since these are the products of these compounds when used in shift reaction, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the same ingredients reacted together in the same way would produce the same results.
As to the water reduction step, Fig. 2 of Harkness shows that water is purged from the gas stream (see Fig. 2, 46 , water stream that is separated from the gas streams 42 and 44).
As to Claim 3, Harkness shows that after the sulfur scrubber and before the compressor in Fig. 2 (col. 3, lines 67-68), there is a means used to convert the sulfur-containing impurities to hydrogen sulfide (col. 4, lines 1-3). The sulfur scrubber is considered a sulfur condensing step since the scrubbing step adds water to the sulfur gas stream to produce a liquid stream.
As to Claim 4, Harkness teaches that the catalytic reduction unit, 34, used to perform the hydrogenation step and the shift reaction is in 34 (col. 3, lines 65-38 to col. 4, lines 1-9), which can be described as a catalytic reactor.
As to Claim 9, Harkness teaches that the stream may be treated using a membrane separation unit (col. 4, line 19).
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Harkness as applied to claim 3 above, and further in view of Shi (CN 111013536).
Harkness describes use of an absorption device, which is used to remove impurities, such as H2S (col. 4, lines 19-23). Harkness then states that H2S may be recycled and sent back to the plasma reactor (col. 4, lines 22-24).
Harkness does not teach regenerating the absorber.
Shi describes a H2S sorbent (title) and explains that hydrogen sulfide adsorbents may be regenerated (abstract) and the hydrogen sulfides may be recycled (abstract).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to regenerate the absorber, as taught by Shi for use with desorbed H2S that is then recycled, as taught by Harkness because desorbing H2S from H2S absorbers is known to be regenerated for reuse.
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Harkness as applied to claim 2 above, and further in view of Mchugh (CN 113874476).
Harkness describes that after performing a catalytic reduction, the stream is then sent to an adsorption step (col. 4, lines 15-20). Harkness does not disclose an intermediate quench step.
Mchugh explains that in their process to treat pollutants, they use a a water gas shift catalyst to reduce some of the pollutants (page 6, last 5 lines). Following this, Mchugh explains that “Typically, the reactor effluent is cooled by a waste heat boiler. . and then through a water quench tower system, which cools the gas and reduces the water content (page 6, last para). Following this step, the stream is then fed to an amine-absorption system used to remove H2S (page 7, para. 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use an intermediate quenching system, as taught by Mchugh for use with the process of Harkness because Mchugh explains that this is typical in the field for treating H2S-containing gases prior to feeding the stream to an adsorption tower.
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Harkness as applied to claim 1 above, and further in view of Donath (US Pat.: 3840354).
Harkness explains that hydrogen may be separated as an impurity from the stream (col. 4, lines 20-21). Harkness does not teach use of a cryogenic hydrogen separator.
Donath describes a method o purifying a stream using a a purification apparatus (col. 8, line 33). The process passes the gas through a water-gas-shift reactor to remove H2S and CO2 (col. 8, lines 34-36). The purified gas is then passed through a compressor (col. 8, line 41) where the gas is then fed to a hydrogen separator (col. 8, line 47). The hydrogen separator may be a cryogenic separator used to remove H2 and hydrogen-rich gas using cryogenic means (col. 8, lines 48-50).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to remove hydrogen using a cryogenic hydrogen separator, as taught by Donath for use with the process of Harkness because cryogenic hydrogen separation is known to be removed using cryogenic hydrogen separation.
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Harkness as applied to claim 1 above, and further in view of Schulz (CN 107083404).
Harkness teaches removing hydrogen from the stream that passed through the water gas shift reactor using a pressure absorption system (col. 4, lines 19, 20).
Harkness does not disclose use of a pressure swing adsorption system to remove the H2.
Schulz describes a method of purifying a stream (see “steam reforming system”) used with a water gas shift module 6 (see page 25 “steam reforming system”). The stream derived from the water gas shift module is then sent to a pressure swing adsorption module to recover hydrogen from the stream (page 25, “steam reforming system”).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ a pressure swing adsorber, as taught by Schulz in replacement of the pressure absorption system of Harkness because Shultz explains that a means for purifying a gas stream from a water gas shift module is known to recover hydrogen using a pressure swing adsorber.
Claim(s) 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Harkness as applied to claim 1 above, and further in view of Han (CN 112657558).
Han describes use of a plasma modified catalyst device used in removing hydrogen sulfide (title). Han explains that plasma used produces a plasma using a dielectric barrier (“description”, para. 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ a plasma that produces a plasma using a dielectric barrier, as taught by Han for use with the process of Harkness because it is known to generate a plasma using this type of device.
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Harkness as applied to claim 1 above, and further in view of Wang (CN 102408095).
Wang teaches a method of decomposing hydrogen sulfide (title). The method feeds a H2S-containing gas into a plasma made using a dielectric barrier (abstract). The plasma device contains a catalyst that can include a metal sulfide (abstract) or a carbon or zeolite catalyst (para. 11).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ a plasma device with a catalyst that can be a metal sulfide, carbon or zeolite, as taught by Wang for use with the plasma device of Harkness because Wang explains that these devices are known to effectively decompose H2S in a gas stream.
Allowable Subject Matter
Claim 12 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is an examiner’s statement of reasons for allowance: Harkness and the other references do not describe adding a Claus reaction downstream of the plasma reactor.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SHENG HAN DAVIS whose telephone number is (571)270-5823. The examiner can normally be reached 9-5:30.
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/SHENG H DAVIS/Primary Examiner, Art Unit 1732 September 3, 2026
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