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 .
Claim Status
The claims are not newly amended.
Response to Arguments
Applicant’s arguments, filed 4/30/26, with respect to the rejection(s) of the claim under the non-final have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of the references below.
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) 11, 13, 15, 16, 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stone (US Pat.: 5948269) and in view of Ra (KR 101751207) and evidenced by ChemicalAid.
Stone describes a process for the removal and suppression of H2S and other acid compounds in a stream (title) by making an aqueous solution that comprises an iron salt with an alkali salt that can be a bicarbonate, carbonate and an alkali hydroxide (col. 5, lines 1-7). The iron is in ferric and ferric form (col. 4, lines 25-26, Fe III and col. 5, lines 1-5). The process of making the product includes combining an aqueous solution of an iron salt that can be a ferric salt (col. 5, lines 1-4) mixing the ferric salt with an aqueous solution of a sodium alkaline salt, such as bicarbonate or carbonate (col. 5, lines 4-6). The product made is an alkaline iron (col. 4, line 19). This can be considered an alkali iron complex. Since the iron can be in ferric form (see above) and the alkali can be an alkali carbonate (see above), the complex can be considered a ferric carbonate complex.
Stone does not disclose use of potassium bicarbonate or carbonate.
As to the amounts, Stone teaches use of stoichiometric amounts (col. 5, lines 5-8), but does not describe the ratio of K:Fe.
As to the use of potassium instead of sodium, Ra describes a method of desulfurizing using a scrubbing means (title). The scrubber can be used to remove H2S (abstract). Ra explains that the chemical liquid used for desulfurization include potassium carbonate and ferric chloride aqueous solution, which are effect to absorb sulfur components in the gas (page 3, lines 18-22).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ potassium carbonate instead of sodium carbonate, as taught by Ra for use with the H2S scrubbing solution of Stone because use of potassium carbonate in place of sodium carbonate is known to have expected and predictable results that would effectively remove H2S from a stream.
As to the ratio of K to Fe, Stone teaches that the amount of alkali carbonate added to the ferric chloride is a stoichiometric amount (col. 5, lines 1-8). Stone does not state how much of each are used however.
ChemicalAid shows that the reaction of iron chloride and potassium carbonate is balanced when iron chlorides are added in a ratio with potassium carbonate in an amount of 2:3 (see attached).
As to the temperature range, neither Stone or ChemicalAid describe reacting the iron and carbonate salts at a temperature of 20-55 degrees C. However, since this temperature range overlaps ambient temperature, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the reaction temperature of Stone is ambient temperature.
As to Claim 13, Stone teaches that their iron is an aqueous solution of iron salts (col. 5, lines 1-3) and that the alkaline salt is a semi-solid slurry (col. 5, lines 4-6). This will be treated to mean that the alkali salt contains solids and solution.
The two are reacted together to form a precipitate (col. 5, line 10).
As to Claim 15, this feature is optional and therefore not required by the process.
As to Claims 16 and 17, Claims 16 and 17 depend upon an optional claim and therefore Claims 16 and 17 are also optional.
Claim(s) 12, 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stone, Ra and evidenced by ChemicalAid as applied to claim 11 above, and further in view of Ning (CN 101091869).
The references teaches combining the compounds, but does not teach that the iron is a solid and added to an aqueous solution of the alkali metal carbonate.
Ning teaches purification of a hydrogen sulfide-containing stream using a reagent (title). The reagent is made by dissolving a ferric chloride in an aqueous absorption liquid comprising water (“Novelty”). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that since the ferric chloride is dissolved into the aqueous solution, that the ferric chloride is in a solid form prior to the dissolution.
After this dissolution, Ning teaches adding the alkali carbonate and/or alkali bicarbonate (“Novelty”).
Although Ning does not specifically teach that the iron salt is added to the aqueous solution containing alkali carbonate and/or alkali bicarbonate and that the alkali carbonate and/or alkali bicarbonate is added to the aqueous solution prior to adding the iron salt, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to change the order of addition of the iron salt and alkali carbonate and/or alkali bicarbonate in order to arrive at the same composition.
See: Changes in Sequence of Adding Ingredients Ex parte Rubin , 128 USPQ 440 (Bd. App. 1959) (Prior art reference disclosing a process of making a laminated sheet wherein a base sheet is first coated with a metallic film and thereafter impregnated with a thermosetting material was held to render prima facie obvious claims directed to a process of making a laminated sheet by reversing the order of the prior art process steps.). See also In re Burhans, 154 F.2d 690, 69 USPQ 330 (CCPA 1946) (selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results); In re Gibson, 39 F.2d 975, 5
USPQ 230 (CCPA 1930) (Selection of any order of mixing ingredients is prima facie
obvious.) see MPEP §2144.04
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to add the iron salt in the form of a solid, as taught by Ning for use with the iron source of Stone, Ra and evidenced by ChemicalAid because use of a solid precursor as the iron source is known to achieve the predictable and effective results that result in an iron-containing solution upon combining with an aqueous solution.
Claim(s) 18, 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stone, Ra and evidenced by ChemicalAid as applied to claim 11 above, and further in view of Primack (US Pub.: 4374104).
The references teach use of a ferric salt material, such as ferric chloride, but does not teach that the ferric salt is a ferric nitrate.
Primack describes a method for removing hydrogen sulfide from a gas stream (title). The method uses a ferric salt that includes ferric chloride, ferric sulfate or ferric nitrate (col. 4, lines 16-18). This is then combined with an alkali material, such as sodium carbonate, which is used to adjust the pH of the solution (col. 4, lines 22-26).
It would have been obvious to one skilled in the art to substitute ferric nitrate, as taught by Primarck by its functional equivalent ferric chloride, as taught by Stone, Ra and evidenced by ChemicalAid with expected success. See MPEP 2144.06.
As to Claim 19, Stone teaches precipitating alkaline iron compound in a slurry (col. 5, lines 9-11), which are then added to a waste stream for use (col. 5, line 12). The waste stream can be wastewater (Claim 7), which can be considered a further dilution step.
Claim(s) 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 is/are rejected under 35 U.S.C. 103 as being unpatentable over Stone, Ra and evidenced by ChemicalAid as applied to claim 11 above, and in view of Primack (US Pub.: 4374104) and in view of Roberts (US Pat.: 3622273) and further in view of Ning (CN 101091869).
As to Claims 20, 21 and 30, Stone teaches combining an iron salt with an alkali salt, such as bicarbonate or carbonate (col. 5, lines 3-5). In one example, Stone teaches that the alkaline salt added can include sodium bicarbonate, sodium carbonate, sodium hydroxide and mixtures thereof (Claim 17). Stone teaches that the product made is an alkaline iron (col. 4, line 19). This can be considered an alkali iron complex. Since the iron can be in ferric form (see above) and the alkali can be an alkali carbonate (see above), the complex can be considered a ferric carbonate complex. The alkali is anionic after combined with iron (col. 4, line 16). Stone explains that the alkaline iron is soluble in water (col. 4, lines 21-23). As to the pH, Stone explains that when added to water, the alkalinity of the alkaline iron is released from the alkaline iron compound and increases the pH (col. 3, lines 8-15). The iron portion then reacts with sulfur (col. 4, lines 35-38). Since iron is soluble in water and Stone explains that the alkaline iron dissociates and the alkaline solubilizes (see col. 4, line 25-27, “soluble alkalinity”), it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the alkaline iron is soluble at high pHs, to include a pH above 8.5 because as more alkaline is added to the water, more alkaline from the alkaline iron solubilizes to increase the pH.
As to the pH, Roberts teaches a method for removing H2S from a gaseous stream by contacting this stream with a ferric ion complex in water and with a buffering agent (abstract). Roberts explains that the buffering agent can be potassium carbonate (col. 3, line 46). As to the amount, the buffering agent is added in order to obtain the desired pH levels (col. 3, lines 50-55) because the solubility of H2S improves above a pH of 4 (col. 3, line 71).
Roberts does not disclose a specific pH level however.
Ning teaches a means of removing H2S from a gas stream (title). The process employs ferric chloride in solution to remove the contaminant (Novelty). The reference explains that sodium carbonate and/or bicarbonate are used to adjust the pH of the solution to 8-10 to remove H2S (Novelty).
The reference explains that the addition of sodium carbonate and/or bicarbonate results in a pH of 8-10 (Novelty).
Therefore, since Stone explains that solubilizing alkaline iron releases alkali, which then increases the pH of the solution, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to add alkaline iron so that the release of the carbonate and/or bicarbonate would reach and/or overlap a pH of about 8-10, as taught by Ning for use the hydrogen sulfide sequestering of Roberts because Roberts explains that a higher pH would solubilize hydrogen sulfide and facilitates the removal of this compound in the stream.
As to the ratio of K to Fe, Roberts explains that the iron concentration can be about 0.12 % (col. 6, lines 16-17) and the ratio with the buffering reagent is from 0.05 to 10% (see claim 1).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ potassium to iron in the ratio described above, as taught by Roberts for use with the ferric complex for removing H2S of Stone, Ra and evidenced by ChemicalAid because this ratio is known to raise the pH of the solution to effectively solubilize H2S for improved results.
As to Claims 22 and 24, Stone teaches that the resultant alkali iron is precipitated from solution that can be used again in the same waste stream (col. 5, lines 10-12). Since a precipitate is a solid, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that use of the alkali iron precipitate of Stone meets the feature of a solid that comprises at least one ferric iron salt reagent.
The other additive is a semi-solid slurry of an alkali salt (col. 5, lines 4-6). The two are reacted in wastewater to form a new alkaline iron product (see Claim 7).
As to Claim 23, Stone teaches that the ferric salt is combined with a semi-solid alkaline carbonate salt (col. 5, lines 4-7). This can be considered a solid compound. The iron and alkali salt can be combined in wastewater to form a new alkaline iron product (see Claim 7).
As to Claim 25, these features are all optional and therefore not required.
Claim 26 depends on Claim 25. The features of Claim 25 are optional.
As to Claim 28, Primack describes a method for removing hydrogen sulfide from a gas stream (title). The method uses a ferric salt that includes ferric chloride, ferric sulfate or ferric nitrate (col. 4, lines 16-18). This is then combined with an alkali material, such as sodium carbonate, which is used to adjust the pH of the solution (col. 4, lines 22-26).
It would have been obvious to one skilled in the art to substitute ferric nitrate, as taught by Primarck by its functional equivalent ferric chloride, as taught by Stone, Ra and evidenced by ChemicalAid with expected success. See MPEP 2144.06.
As to Claim 29, Stone teaches precipitating alkaline iron compound in a slurry (col. 5, lines 9-11), which are then added to a waste stream for use (col. 5, line 12). The waste stream can be wastewater (Claim 7), which can be considered a further dilution step.
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 June 15, 2026
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