Prosecution Insights
Last updated: September 29, 2026
Application No. 18/390,290

PROCESS TO CONTINUOUSLY TREAT A HYDROGEN SULPHIDE COMPRISING GAS

Final Rejection §103§112
Filed
Dec 20, 2023
Priority
Jun 21, 2021 — NL 2028503 +1 more
Examiner
SWIFT, CANDICE LEE
Art Unit
1657
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Paques I P B V
OA Round
2 (Final)
58%
Grant Probability
Moderate
3-4
OA Rounds
5m
Est. Remaining
94%
With Interview

Examiner Intelligence

Grants 58% of resolved cases
58%
Career Allowance Rate
73 granted / 127 resolved
-2.5% vs TC avg
Strong +36% interview lift
Without
With
+36.0%
Interview Lift
resolved cases with interview
Typical timeline
3y 2m
Avg Prosecution
52 currently pending
Career history
192
Total Applications
across all art units

Statute-Specific Performance

§101
9.4%
-30.6% vs TC avg
§103
29.0%
-11.0% vs TC avg
§102
9.4%
-30.6% vs TC avg
§112
31.9%
-8.1% vs TC avg
Black line = Tech Center average estimate • Based on career data from 127 resolved cases

Office Action

§103 §112
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 . DETAILED ACTION Claims 1-22 are pending. Election/Restrictions Applicant’s election without traverse of Group I, claims 1-20, in the reply filed on 3/9/2026 is acknowledged. Claims 21-22 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim.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 3/92-27. Claims 1-20 are examined herein. Priority Acknowledgment is made of applicant's claim for foreign priority based on an application filed in the Netherlands on 6/21/2021. It is noted, however, that applicant has not filed a certified copy of the NL2028503 application as required by 37 CFR 1.55. Claim Objections Claims 8 and 13-15 are objected to because of the following informalities: In claim 8, “polysulfide” should be changed to “polysulphide” for consistency with the remainder of the claims. In claim 13, “continuously the hydrogen sulphide comprising gas is fed.” Continuously is misplaced and should occur after fed. In claim 14, “part of the aqueous liquid comprising sulphide-oxidising bacteria is continuously fed to an intermediate position of the column to contact together with the intermediate loaded aqueous liquid with the upflowing gaseous stream in a second contacting zone” is missing commas and contains an extraneous “with.” Applicant may consider amending to “part of the aqueous liquid comprising sulphide-oxidising bacteria is continuously fed to an intermediate position of the column to contact the intermediate loaded aqueous liquid and the upflowing gaseous stream in a second contacting zone. In claim 15, “wherein as part of (a) part of the aqueous liquid comprising sulphide-oxidising bacteria is (a1) continuously contacted in with the hydrogen sulphide comprising gas to obtain a first intermediate loaded aqueous liquid” is convoluted and should be reworded to remove the “part of (a) part of” language. Additionally, the word “in” is extraneous in “in with.” Similarly, “wherein as part of (a) another part of” is convoluted and should be reworded. Appropriate correction is required. 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 1-20 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. Claim 1 is indefinite for “polysulphide reactor zone.” The specification does not provide a special definition for “zone” or “polysulphide reactor zone” or provide an objective standard for measuring the extent of a zone. Thus, the person of ordinary skill in the art would have been unable to ascertain the metes and bounds of claim. Similarly, claim 8-12 and 16-19 are indefinite for “polysulphide reactor zone.” Claim 1 recites “a hydrogen sulphide comprising gas.” There are at least two different reasonable interpretations of the claim, rendering the claim indefinite. In one interpretation, the gas comprises hydrogen sulphide (i.e. “a hydrogen sulphide-containing gas”). In a second interpretation, the hydrogen sulphide is in a gas state. In a third interpretation, the hydrogen sulphide further comprises a gas (e.g. hydrogen sulphide further comprising nitrogen gas or any other gas). Applicant may consider amending to “a gas comprising hydrogen sulphide” to obviate this rejection. Claims 6, 13, and 15 recite the same limitation, “the hydrogen sulphide comprising gas,” and are indefinite for the same reason as above. Claim 1 is further indefinite for “wherein content of elemental sulphur as part of the polysulphide compounds in the loaded aqueous liquid [s0 in sx2-] as supplied to (c) is above 0.7 mM.” It is unclear whether the [s0 in sx2-] is required or optional because of the square brackets. Claims 2-3 are similarly indefinite for “the content of elemental sulphur as part of the polysulphide compounds in the loaded aqueous liquid [s0 in sx2-] as supplied to (c).” Claim 4 recites “wherein the content of elemental sulphur as part of the polysulphide compounds in the loaded aqueous liquid meets the following condition” and also recites “wherein [s0 in sx2-] is the content of elemental sulphur as part of the polysulphide compounds in the loaded aqueous liquid as supplied to (c).” The discrepancy between “the loaded aqueous liquid” and “the loaded aqueous liquid as supplied to (c)” leads to ambiguity in the claimed subject matter as it is unclear which loaded aqueous liquid is referred to in the first wherein clause. Claim 7 recites “wherein the aqueous alkaline liquid is increased in temperature by indirect heat exchange with the loaded aqueous liquid and/or with an external heat source thereby obtaining a heated aqueous alkaline liquid which is used in (a).” It is unclear how the heated aqueous alkaline liquid is used in (a). In addition, there is a lack of antecedent basis for “the loaded aqueous liquid” because steps (a)-(c) each recite the loaded aqueous liquid; thus it is unclear which loaded aqueous liquid increases the temperature of the aqueous alkaline liquid. Claim 11 recites “the part of the loaded aqueous liquid as isolated from the downstream region, before it is recycled to the upstream region in the polysulphide reactor zone.” There is a lack of antecedent basis for this limitation in the claim because claim 10 does not recite any step of isolating part of the loaded aqueous liquid from the downstream region. Claim 11 is further indefinite for “wherein the part of the loaded aqueous liquid as isolated from the downstream region, before it is recycled to the upstream region in the polysulphide reactor zone, flows via a zone having a residence time of between 5 and 45 minutes.” The person of ordinary skill in the art would have been unable to determine the metes and bounds of this claim because it is unclear which zone is required to have the residence time. The zone could reasonably be interpreted as the entire length of the recycle loop or a portion of the recycle loop. In the latter case, it is unclear how this portion of the recycle loop is defined. Claim 15 recites “as part of (a) part of .” It is unclear whether claim 15 is further limiting the existing step (a) or whether claim 15 is reciting additional method steps (a1) and (a2) that occur after step (a) and before step (b). Claim 16 recites “in which polysulphide reactor zones polysulphide compounds are formed by reaction of the dissolved sulphide and the elemental sulphur.” It is unclear whether polysulphide compounds, polysulphide reactor zones, or polysulphide compounds in the polysulphide reactor zones are formed. Claim 18 recites “the first intermediate loaded aqueous liquid rich in polysulphides” in lines 1-2 There is a lack of antecedent basis for this limitation in the claim. Claims 2-20 are rejected for depending from a rejected base claim and not rectifying the sources of indefiniteness discussed above. 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. Claims 4-5 and 16 are 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. Claims 4-5 fail to further limit claim 1 because claims 4-5 each recite a mathematical relationship that does not limit the active method steps of claim 1. Note that claim 1 already recites a requirement for the content of elemental sulfur in the polysulphide compounds. Claim 16 fails to include all the limitations of the claim upon which it depends. Claim 16 recites that the first and second loaded intermediate liquids flow through separate first and second polysulphide reactor zones. However, claim 16 depends from claim 15, which requires that the first intermediate loaded aqueous liquid is combined with the second intermediate loaded aqueous liquid to obtain the loaded aqueous liquid. Claim 15 depends from claim 1, which requires passing the loaded aqueous liquid through a polysulphide reactor zone comprising one or more plug flow reactor zones. Thus, claim 16 fails to include all the limitations of the claim upon which it depends because the claim requires that the first and second intermediate loaded liquids flow through separate first and second polysulphide reactor zones, in which case the first and second loaded intermediate liquids are not combined. Applicant may cancel the claims, amend the claims to place the claims in proper dependent form, rewrite the claims in independent form, or present a sufficient showing that the dependent claims complies with the statutory requirements. 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 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 1-3, 6-8, 10, 12-13, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Kiragosyan et al. (Journal of hazardous materials 398 (2020): 123002; published online May 24, 2020) in view of Kleinjan et al. (Industrial & engineering chemistry research 44.2 (2005): 309-317) and Bridgwater et al. (The Canadian Journal of Chemical Engineering 51.1 (1973): 128-130). Kiragosyan teaches contacting an H2S-containing gas with an alkaline solution (Fig. 1 and page 2, left column, paragraph 2). The H2S-containing gas contacts sulfur oxidizing bacteria, which are inoculated into each bioreactor (page 3, right column, last sentence of top paragraph). The system accumulates elemental sulfur particles (page 3, left column, paragraph 4), so the H2S-containing gas also contacts the elemental sulfur particles due to the recycle stream from the aerobic bioreactor to the gas absorber (Fig. 1). Thus, the recycle stream is an alkaline solution comprising elemental sulfur particles and sulfur-oxidizing bacteria. Kiragosyan teaches passing the effluent from the absorber into an anaerobic reactor before contacting the effluent from the anaerobic reactor with oxygen in the aerobic bioreactor (Fig. 1). Kiragosyan teaches that the concentration of polysulfide compounds in the loaded aqueous liquid supplied to the aerobic bioreactor is 2 mM S day−1 with an average chain length of 4.5 (page 5, right column, bottom paragraph and Fig. 3 on page 6). Thus, the content of elemental sulfur as polysulfide compounds is approximately 7 mM ((4.5-1)×2 mM; see the numerator of equation (5) of Kleinjan for the conversion of polysulfide concentration and polysulfide chain length to the content of elemental sulfur as part of polysulfides). Kiragosyan teaches that the volume of the anaerobic bioreactor is 2.5 L (left column, paragraph 3 on page 3). Kiragosyan teaches that the liquid recirculation rate is 10 L h-1 (page 3, left column, paragraph 1). Thus, the residence time of the anaerobic bioreactor is 15 min, which is within the claimed range of between 3 and 45 min. Kiragosyan does not teach separating the elemental sulfur particles from the enriched aqueous liquid. Rather, Kiragosyan teaches that when sulfur concentrations become too high, the system becomes more difficult to operate as a result of the inadequate separation of the liquid, gas, and solid phases, resulting in the entrainment of sulfur particles in the recirculation gas stream (page 3, left column, paragraph 4). To prevent this, the sulfur content was lowered by partial exchange of the medium on days 12, 29, and 44 (page 3, left column, paragraph 4). Kiragosyan does not teach that the anaerobic reactor (“polysulphide reactor”) comprises one or more plug flow reactor zones. Kleinjan teaches that the conversion of sulfide to polysulfides is an autocatalytic process (Abstract): the more polysulfide that is formed, the faster the reaction proceeds. Kleinjan also teaches that the presence of polysulfide ions increases the rate of dissolution of elemental sulfur into an aqueous sulfide solution (page 310, left column, paragraph 3). Bridgwater teaches that the recycle reactor is advantageous for controlling backmixing because if the recycle ratio is zero, the reactor is in plug flow, whereas the reactor approaches a well-stirred reactor for high recycle (Abstract). Bridgewater teaches that for an autocatalytic reaction, for which it is well-known that backmixing is of key importance, noticeable savings in reactor volume may be obtained by the use of a recycle reactor (Abstract). Bridgewater teaches the configuration of a recycle reactor comprising a plug flow section and a recycle stream (Fig. 1) It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to replace Kiragosyan’s stirred tank anaerobic reactor with Bridgewater’s recycle reactor comprising plug flow reactor zones. The person of ordinary skill in the art would have been motivated by the teachings of both Kleinjan and Bridgwater because Kleinjan teaches that the formation of polysulfides is an autocatalytic reaction and Bridgwater teaches that for autocatalytic reactions, recycle reactors comprising plug flow zones are preferred for the ability to control backmixing. Kleinjan teaches separating sulfur from the liquid after the aerobic bioreactor in a settler and recycling a portion of the sulfur to the gas absorber (page 309, right column, paragraph 2). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to separate a portion of the sulfur from the liquid effluent of the aerobic bioreactor in order to recover the sulfur and avoid having to perform Kiragosyan’s step of partial exchange of the medium. The person of ordinary skill in the art would have recognized this modification as an improvement to the method of Kiragosyan and would have had a reasonable expectation of success in adding this separation step. Regarding claims 2-3, Kiragosyan teaches that the concentration of polysulfide compounds in the loaded aqueous liquid supplied to the aerobic bioreactor is 2 mM S day−1 with an average chain length of 4.5 for about one week (page 5, right column, bottom paragraph and Fig. 3 on page 6). Thus, the content of elemental sulfur as polysulfide compounds is 7 mM, which is above 1 mM and above 0.7 mM. Regarding claim 6, Kiragosyan teaches that the hydrogen sulfide volume fraction is 1.5% (page 2, right column, bottom paragraph), which is within the claimed range of 0.1 and 3 vol%. Kiragosyan does not teach that the carbon dioxide content is above 20 vol%. Kiragosyan teaches that the carbon dioxide supply is controlled with a pH sensor (page 3, left column, paragraph 1). Kiragosyan teaches that the pH is maintained at 8-10 (page 2, left column, paragraph 2). Kiragosyan teaches that 0-17 mL min-1 mass flow controller supplies hydrogen sulfide and a 0-40 mL min-1 mass flow controller supplies carbon dioxide (page 2, right column, bottom paragraph). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to optimize by routine experimentation the carbon dioxide content of the gas based upon the pH in the absorber column, as suggested by Kiragosyan. The person of ordinary skill in the art would have had a reasonable expectation of success in optimizing the flow of CO2 in the gas to control the pH using the pH sensor. For the lower range of pH, higher concentrations of CO2 would have been required. Regarding claim 7, Kiragosyan teaches that the gas absorber and the bioreactors’ temperature were controlled at 35 °C by a thermostat bath (page 3, left column, paragraph 1). Thus, the aqueous alkaline liquid solution is increased in temperature by an external heat source. Regarding claim 8, Bridgwater teaches a recycle reactor comprising plug flow sections that have an upstream and downstream region (Fig. 1). Regarding claim 10, Bridgewater teaches the recycle stream of the reactor, so part of the liquid is recycled from the downstream region to the upstream region of the anaerobic polysulfide reactor in the process of Kiragosyan modified by Kleinjan and Bridgewater. Regarding claim 12, Kiragosyan teaches that the temperature of the absorber and the anaerobic reactor are maintained by a thermostat bath (page 3, left column, top paragraph). Kiragosyan does not teach that the part of the loaded aqueous liquid which is recycled from the downstream region is increased in temperature before being recycled to the upstream region in the polysulphide reactor zone. It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to heat the recycled effluent from the anaerobic reactor prior to introducing the recycle into the reactor by keeping the recycle loop within the same thermostat bath as the anaerobic reactor. The person of ordinary skill in the art would have been motivated to do so to maintain the temperature of the anaerobic reactor, as per the teaching of Kiragosyan, and the person of ordinary skill in the art would have had a reasonable expectation of success in doing so. Regarding claim 13, Kiragosyan’s Fig. 1 depicts the absorber as a vertical column with the H2S-containing gas entering the column at a lower position and the recycle stream from the aerobic reactor (aqueous liquid comprising bacteria) fed at a higher position of the column, which necessarily results in an upward flowing aqueous stream and a downwards flowing aqueous stream. The process is continuous for two months (page 2, left column, bottom paragraph). Regarding claim 20, Kiragosyan’s Fig. 1 illustrates a liquid recycle stream from the aerobic reactor to the absorber. Claims 15-17 are rejected under 35 U.S.C. 103 as being unpatentable over Kiragosyan et al. (Journal of hazardous materials 398 (2020): 123002; published online May 24, 2020) in view of Kleinjan et al. (Industrial & engineering chemistry research 44.2 (2005): 309-317) and Bridgwater et al. (The Canadian Journal of Chemical Engineering 51.1 (1973): 128-130), as applied to claims 1-3, 6-8, 10, 12-13, and 20 above, further in view of Qi et al. (Energy Procedia 37 (2013): 1968-1976). See discussion of Kiragosyan, Kleinjan, and Bridgwater above, which is incorporated into this rejection as well. Regarding claim 15, Kiragosyan teaches a single absorption column. Thus, Kiragosyan does not teach that part of the aqueous liquid comprising sulphide-oxidizing bacteria is continuously contacted with the hydrogen sulphide-containing gas to obtain a first intermediate loaded aqueous liquid and an intermediate gas having a lower intermediate content of hydrogen sulphide or that another part of the aqueous liquid comprising sulphide-oxidizing bacteria is continuously contacted with the intermediate gas having a lower intermediate content of hydrogen sulphide to obtain a second intermediate loaded aqueous liquid having a lower content of hydrogen sulphide, wherein the first intermediate and second intermediate loaded aqueous liquids are combined. Qi teaches operating two gas absorbers in series (Fig. 1) in which the gas outlet from the first absorber (“first intermediate gas”) is fed to a second absorber that produces a second gas (“the gas having a lower content of hydrogen sulphide”). Both absorbers receive a solvent: the first absorber receives a semi-rich solvent and the second absorber receives a lean solvent. It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to add a second absorption column in series with the first absorption column, per the teaching of Qi, in order to further decrease the H2S concentration of the gas and thus recover more sulfur from the stream. The person of ordinary skill in the art would have had a reasonable expectation of success in adding the second absorber column in series with the first. The gas outlet from the first absorber (“intermediate gas having a lower intermediate content of hydrogen sulphide”) would have then been the gas inlet to the second absorber and the gas outlet from the second absorber would have had an even lower content of hydrogen sulphide. It would have been further obvious to split the recycle stream from the aerobic reactor into two separate streams (one for each absorber) in order to maximize H2S absorption in each of the absorbers by maximizing the driving H2S concentration gradient between the gas and liquid streams in each of the absorbers. It would have been further obvious to combine the liquid effluent from each of the absorbers and feed them both to the anaerobic reactor, thus avoiding the need for two separate anaerobic reactors. Regarding claims 16-17, these claims are interpreted as requiring that the first and second intermediate loaded aqueous liquids flow through separate first and second polysulphide reactor zones before being combined. Kiragosyan teaches a single anaerobic reactor rather than first and second polysulphide reactor zones comprising plug flow zones. It would have been obvious to the person of ordinary skill in the art before the effective filing date of the claimed invention to feed the liquid effluent from each absorber to two separate anaerobic recycle reactors comprising plug flow zones for the obvious advantage of decreasing the size of the anaerobic recycle reactor. The person of ordinary skill in the art would also have had a reasonable expectation of success in this configuration. Further regarding claims 15-17, both of these configurations (having two separate absorbers in series upstream of a single anaerobic bioreactor or having two separate absorbers in series, the liquid effluent of each absorber flowing into a separate anaerobic reactor) would have been obvious to the person of ordinary skill in the art, such as a process engineer, as mere optimization of the equipment configuration of Kiragosyan by duplicating existing operational units (the absorber and the anaerobic reactor). Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Kiragosyan et al. (Journal of hazardous materials 398 (2020): 123002; published online May 24, 2020) in view of Kleinjan et al. (Industrial & engineering chemistry research 44.2 (2005): 309-317) and Bridgwater et al. (The Canadian Journal of Chemical Engineering 51.1 (1973): 128-130), as applied to claims 1-3, 6-8, 10, 12-13, and 20 above, further in view of De Rink et al. (Environmental science & technology 53.8 (2019): 4519-4527). See discussion of Kiragosyan, Kleinjan, and Bridgwater above, which is incorporated into this rejection as well. Regarding claim 11, Kiragosyan, Kleinjan, and Bridgwater do not teach the residence time in the recycle loop. De Rink teaches that the purpose of the anaerobic reactor in the dual bioreactor gas biodesulfurization system is to impose extra retention time for the sulfur-oxidizing bacteria in the HS- rich process solution from the H2S absorber in order to decrease the HS- concentration in the influent of the aerobic bioreactor, thus decreasing the chemical oxidation to unwanted byproducts in the aerobic bioreactor (page 4520, right column, paragraph 1). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to optimize by routine experimentation the residence time in the recycle stream of the anaerobic reactor in order to decrease the amount of HS- in the inlet to the aerobic bioreactor. The person of ordinary skill in the art would have had a reasonable expectation of success in optimizing the residence time of the recycle loop of the anaerobic bioreactor. Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Kiragosyan et al. (Journal of hazardous materials 398 (2020): 123002; published online May 24, 2020) in view of Kleinjan et al. (Industrial & engineering chemistry research 44.2 (2005): 309-317) and Bridgwater et al. (The Canadian Journal of Chemical Engineering 51.1 (1973): 128-130), as applied to claims 1-3, 6-8, 10, 12-13, and 20 above, further in view of Towler et al. (Proceedings of the Annual Convention-Gas Processors Association. Gas Processors Association, 1997). See discussion of Kiragosyan, Kleinjan, and Bridgwater above, which is incorporated into this rejection as well. Regarding claim 14, Kiragosyan does not teach that part of the aqueous liquid comprising sulphide-oxidizing bacteria is continuously fed to a higher position of the column to contact with the upflowing gaseous stream in a first contacting zone which generates an intermediate loaded aqueous liquid and part of the aqueous liquid comprising sulphide-oxidizing bacteria is continuously fed to an intermediate position of the column to contact together with the intermediate loaded aqueous liquid with the upflowing gaseous stream in a second contacting zone. Towler teaches an absorber with two liquid inlets: a top inlet and an intermediate inlet (Fig. 2). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to split the liquid recycle loop into two separate streams and introduce one stream at the top and one stream in the middle of the column per the teaching of Tower. The person of ordinary skill in the art would have recognized that introducing the liquid in the intermediate section of the column would have increased mass transfer by diluting the H2S in the liquid, thus increasing the driving gradient for mass transfer between the gas stream and the liquid stream. The person of ordinary skill in the art would have had a reasonable expectation of success in splitting the recycle loop and introducing the liquid into a top and intermediate part of the absorber, thus increasing the removal efficiency of H2S from the gas. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to CANDICE LEE SWIFT whose telephone number is (571)272-0177. The examiner can normally be reached M-F 8:00 AM-4:30 PM (Eastern). Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Louise Humphrey can be reached at (571)272-5543. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /LOUISE W HUMPHREY/Supervisory Patent Examiner, Art Unit 1657 /CANDICE LEE SWIFT/Examiner, Art Unit 1657
Read full office action

Prosecution Timeline

Dec 20, 2023
Application Filed
Apr 30, 2026
Non-Final Rejection mailed — §103, §112
Jul 20, 2026
Response Filed
Sep 28, 2026
Final Rejection mailed — §103, §112 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12716082
RECOMBINANT ENDOXYLANASES AND RELATED COMPOSITIONS AND METHODS OF USE
2y 7m to grant Granted Aug 25, 2026
Patent 12709595
NOVEL SYNTHETIC PATHWAY TO BELZUTIFAN
3y 1m to grant Granted Aug 18, 2026
Patent 12692485
PEGYLATED KYNURENINASE ENZYMES AND USES THEREOF FOR THE TREATMENT OF CANCER
5y 9m to grant Granted Jul 28, 2026
Patent 12680091
ENGINEERED LIPASE VARIANTS
2y 3m to grant Granted Jul 14, 2026
Patent 12673075
USE OF STREPTOCOCCUS THERMOPHILUS ST7 FOR MODULATING IMMUNITY AND AGAINST VIRUSES
2y 6m to grant Granted Jul 07, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

Strategy Recommendation AI-generated — please review before filing

Get a prosecution strategy drawn from examiner precedents, rejection analysis, and claim mapping.
Typically takes 5-10 seconds — AI-generated, attorney review required before filing

Prosecution Projections

3-4
Expected OA Rounds
58%
Grant Probability
94%
With Interview (+36.0%)
3y 2m (~5m remaining)
Median Time to Grant
Moderate
PTA Risk
Based on 127 resolved cases by this examiner. Grant probability derived from career allowance rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month