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 .
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.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 6 February 2026 has been entered.
Claim Amendments
Applicant’s amendments to the claims filed on 6 February 2026 have been received and considered for this action.
Claim Interpretation
The term “wuestite” appears in claims 1 and 21. Previously, this term was interpreted as referring to the pure iron(II) oxide, FeO. However, upon further review of the specification and the prior art, wuestite is considered instead as referring more broadly to compounds of formula Fe1-xO, where 0≤x<1/3, as defined on p. 4, lines 19 and 29-30. Charge balance dictates that this compound will contain 2x equivalents of Fe3+ for every (1-3x) equivalents of Fe2+, as also evidenced by Hazen et al. (Reviews of Geophysics and Space Physics, 1984, 22(1), 37-46; p. 1, ¶ 5).
However, it is noted that this broad definition of “wuestite” includes compositions of iron oxide such as Fe0.75O, which is compositionally equivalent to Fe3O4 (magnetite), as well as Fe0.67O, which is very nearly Fe2O3 (hematite). It would be inconsistent with the ordinary meaning of the term ”wuestite” to say that magnetite is wuestite absent a clearer indication that this is what applicant intends. Therefore, in order for a compound to be considered “wuestite,” in addition to the chemical composition recited in the specification, it should also have structural features such that one of ordinary skill in the art would consider it wuestite, or be prepared by a method recognized to produce wuestite.
Claims 19 and 22 each recite the limitation “wherein the iron compounds in the catalyst lack iron(III) compounds”. The broadest reasonable interpretation of the term “iron(III) compounds” in the context of these claims is that the term encompasses any compound that contains iron(III) ions, even if these are not the majority of the iron ions in the compound. For example, wuestite of the formula Fe1-xO is interpreted here as an “iron(III) compound” whenever x>0 because it will contain at least some iron(III) ions.
Claim Objections
Claim 21 is objected to because of minor informalities and should be amended as follows:
“…wherein the iron compounds [[in]] of the catalyst are 100% by weight wuestite.”
Appropriate correction is required.
Claim Rejections - 35 USC § 102
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.
Claims 1, 17, 21, 23, and 24 rejected under 35 U.S.C. 102(a)(1) as being anticipated by Hu et al. (CN 1485135 A). The provided English machine translation of Hu (CN 1485135 A). is relied upon in the analysis below.
Regarding claims 1 and 17, Hu discloses an iron-containing catalyst for ammonia synthesis ([0004] and Example 7, [0031]) comprising iron compounds at 95.1% by weight and the promoters potassium, calculated as K2O, in an amount of 0.5% by weight, calcium, calculated as CaO, in an amount 1.5% by weight, and aluminum, calculated as Al2O3, in an amount of 1.4% by weight (1.0% supplied as Al2O3 and 0.2% supplied as Al which is equivalent to 0.4% when calculated as Al2O3), based on the total weight of the catalyst. The amounts of iron and each promoter fall within the instantly claimed ranges of claims 1 and 17, as set forth in the table below.
Compounds
Claim 1 Range
Claim 17 Range
Hu Example 7
Iron Compounds
>90
>90
95.1
K2O
0.1-0.5
0.1-0.5
0.5
CaO
0.8-2.2
0.8-2.2.2
1.5
Al2O3
1.2-2.0
1.35-1.75
1.4
Hu also teaches the that the catalyst is formed by melting magnetite and iron powders to form wuestite (ferrous oxide; [0015]), and in particular a product that has an Fe2+/Fe3+ ratio of 10.9:1 ([0031]), which corresponds to a molecular formula of Fe0.96O, fitting the characterization of wuestite, as described in the instant specification (p. 4, lines 29-30). The iron compounds in the catalyst disclosed by Wu are therefore considered as consisting essentially of wuestite.
Regarding claims 21 and 23, Hu discloses the composition of claim 1, where the iron compounds can be described as consisting of wuestite with the formula Fe0.96O, as analyzed for claim 1, and therefore lack Fe2O3 and Fe3O4, and meet the limitations of claim 21 and 23.
Regarding claim 24, Hu discloses the composition of claim 1, where the other elements present in Example 7 ([0031]) are tungsten, titanium, vanadium, aluminum, strontium, and magnesium. None of the elements are rare earths, and this composition therefore meets the limitations of claim 24.
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.
Claims 1-2, 15-17, and 19-30 rejected under 35 U.S.C. 103 as being unpatentable over Liu et al. (CN 109772339 A) as evidenced by Ross (“An Introduction to Heterogeneous Catalysis and Its Development Through the Centuries—Chemistry in Two Dimensions”, Chapter 1 of Contemporary Catalysis, 2019, p. 3-38).
Regarding claim 1, Liu discloses an iron-containing catalyst composition (Example 4, [0045]) comprising iron compounds at 94.36% by weight and the promoters potassium, calculated as K2O, in an amount of 0.6% by weight, calcium, calculated as CaO, in an amount 1.5% by weight, and aluminum, calculated as Al2O3, in an amount of 2.0% by weight, based on the total weight of the catalyst. The amounts of calcium and aluminum each fall within the instantly claimed ranges, while the amount of potassium lies just outside the claimed range for potassium of 0.1% to 0.5% by weight.
Liu also teaches the that the iron compounds in the catalyst composition consist essentially of wuestite (identified by XRD as mainly FeO), and that the ratio of Fe2+ to Fe3+ is 7.1:1, which corresponds to a molecular formula of Fe0.94O, fitting the characterization typical of wuestite, as described in the instant specification (p. 4, lines 29-30).
Regarding the amount of potassium in the catalyst, while the content in Example 4 of Liu lies just outside the range of the instant claim, Liu also teaches that the potassium content is preferably within the range 0.2% to 2% ([0020]), which overlaps with the instantly claimed range.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the amount of potassium in the catalyst composition of Liu to anywhere in the range 0.2% to 2.0%, including into the portion that overlaps with the instantly claimed range. One of ordinary skill in the art would have been motivated to do so because Liu teaches that these are also preferred compositions.
It is noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists (see In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); Titanium Metals Corp. of America v. Banner, 778 F2d 775. 227 USPQ 773 (Fed. Cir. 1985) (see MPEP 2144.05.01). Therefore, the claimed ranges of potassium content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Regarding the catalyst functioning as a catalyst for ammonia synthesis, it is noted that because the composition taught by Liu is substantially similar to that instantly claimed that it is expected to have the same function.
It is further noted that Liu teaches that their composition is able to catalyze the decomposition ammonia to hydrogen, which is the reverse reaction of the ammonia synthesis reaction. It is well recognized that a composition that is able to catalyze the forward reaction can also catalyze its reverse, as evidenced by Ross (p. 22, Box 1.8). Therefore the catalysts of Liu are also catalysts for ammonia synthesis.
Table comparing different embodiments taught by Liu with the ranges of claims 1 and 2.
Compounds
Claim 1 Range
Claim 2 Range
Liu Example 4
Liu Example 6
Liu Preferred Range
Iron Compounds
>90
>90
94.3
92.4
85-95
K2O
0.1–0.5
0.15–0.4
0.6
0.92
0.2–2
CaO
0.8–2.2
0.8–2.0
1.5
1.3
0.5–4
Al2O3
1.2–2.0
1.3–1.9
2.0
1.5
0.5–4
Regarding claim 2, Liu teaches the iron-containing catalyst of claim 1, as analyzed above, wherein Example 4 of Liu has potassium, calculated as K2O, present in an amount of 0.6% by weight, calcium, calculated as CaO, present in an amount 1.5% by weight, and aluminum, calculated as Al2O3, present in an amount of 2.0% by weight, based on the total weight of the catalyst.
The amount of calcium in Example 4 lies within the instantly claimed range of 0.8% to 2.0% by weight, and it would have been obvious to vary the amount of potassium within the range of 0.2% to 2.0% by weight, as analyzed for claim 1, which overlaps with the instantly claimed range of 0.15% to 0.4%.
Liu also teaches that the amount of aluminum, calculated as Al2O3, can be varied with a preferable range of 0.4%-4% ([0019]), which overlaps with the claimed range of 1.3% to 1.9%.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify catalyst of Liu such that the amount of aluminum in the catalyst composition is anywhere in the range 0.5% to 4.0%, including into the portion of the range that overlaps with the instantly claimed range. One of ordinary skill in the art would have been motivated to do so because Liu teaches that these are also preferred compositions.
It is again noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists. Therefore, the claimed ranges of potassium and aluminum content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Alternatively, Liu also teaches a second iron-containing catalyst (Example 6, [0051]) comprising iron compounds at 92.4% by weight and the promoters potassium, calculated as K2O, in an amount of 0.92% by weight, calcium, calculated as CaO, in an amount 1.3% by weight, and aluminum, calculated as Al2O3, in an amount of 1.5% by weight, based on the total weight of the catalyst. The amounts of calcium and aluminum each fall within the instantly claimed ranges. Additionally, as analyzed for claim 1, this catalysts are also considered as consisting essentially of wuestite (identified by XRD as mainly FeO, with a molar ratio of Fe2+to Fe3+ of 8.4:1; [0052]) and can also serve as catalysts for ammonia synthesis.
The amount of potassium in this embodiment lies outside the range for potassium of 0.15% to 0.4% by weight required by claim 2. But again, Liu also teaches that the preferable range for potassium content spans 0.2% to 2% by weight ([0019]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify catalyst of Liu’s Example 6 such that the amount of potassium amount in the catalyst composition is anywhere in the range 0.2% to 2%, including into the portion that overlaps with the instantly claimed range. One of ordinary skill in the art would have been motivated to do so because Liu teaches that these are also preferred compositions.
It is again noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists. Therefore, the claimed range of aluminum content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Regarding claims 15 and 16, Liu teaches the catalyst of claim 1, where Liu teaches the potassium being present in the range of 0.2-2.0% by weight ([0045]), which overlaps with the range of 0.1-0.4% by weight required by claim 15 and the range of 0.1-0.3% by weight required by claim 16.
It is again noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists. Therefore, the claimed ranges of potassium content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Regarding claim 17, Liu teaches the iron-containing catalyst of claim 1, as analyzed above, wherein Example 4 of Liu has aluminum, calculated as Al2O3, present in an amount of 2.0% by weight, based on the total weight of the catalyst ([0045]) which lies outside the claimed range of 1.35-1.75% by weight.
However, Liu also teaches that the preferable range for aluminum content spans 0.5% to 4% by weight ([0019]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify catalyst of Liu such that the amount of aluminum in the catalyst composition is anywhere in the range 0.5% to 4.0%, including into the portion that overlaps with the instantly claimed range. One of ordinary skill in the art would have been motivated to do so because Liu teaches that these are also preferred compositions.
It is again noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists. Therefore, the claimed range of aluminum content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Alternatively, Liu also teaches the iron-containing catalyst where (Example 6, [0051]) comprising iron compounds at 92.4% by weight and the promoters potassium, calculated as K2O, in an amount of 0.92% by weight, calcium, calculated as CaO, in an amount 1.3% by weight, and aluminum, calculated as Al2O3, in an amount of 1.5% by weight, based on the total weight of the catalyst. Additionally, as analyzed for claim 1, this catalysts are also considered as consisting essentially of wuestite (identified by XRD as mainly FeO, with a molar ratio of Fe2+to Fe3+ of 8.4:1; [0052]) and can also serve as catalysts for ammonia synthesis.
The amounts of calcium and aluminum for this embodiment each fall within the instantly claimed ranges, while the amount of potassium lies outside the range for potassium of 0.1% to 0.5% by weight required by claim 1.
However, Liu also teaches that the preferable range for potassium content spans 0.2% to 2% by weight ([0019]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify catalyst of Liu’s Example 6 such that the amount of potassium amount in the catalyst composition is anywhere in the range 0.2% to 2%, including into the portion that overlaps with the instantly claimed range. One of ordinary skill in the art would have been motivated to do so because Liu teaches that these are also preferred compositions.
It is again noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists. Therefore, the claimed range of aluminum content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Regarding claim 19, Liu discloses an iron-containing catalyst composition (Example 4, [0045]) comprising iron compounds at 94.36% by weight and the promoters potassium, calculated as K2O, in an amount of 0.6% by weight, calcium, calculated as CaO, in an amount 1.5% by weight, and aluminum, calculated as Al2O3, in an amount of 2.0% by weight, based on the total weight of the catalyst. The amounts of calcium and aluminum each fall within the instantly claimed ranges, while the amount of potassium lies just outside the claimed range for potassium of 0.1% to 0.5% by weight.
Liu also teaches the that the iron compounds in the catalyst composition consist essentially of wuestite (identified by XRD as mainly FeO), and that the ratio of Fe2+ to Fe3+ is 7.1:1. As such, the iron compounds in this particular embodiment cannot be considered as lacking iron(III) compounds.
Regarding the amount of potassium in the catalyst, while the content in Example 4 of Liu lies just outside the range of the instant claim, Liu also teaches that the potassium content is preferable within the range 0.2% to 2% ([0020]), which overlaps with the instantly claimed range.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the amount of potassium in the catalyst composition of Liu to anywhere in the range 0.2% to 2.0%, including into the portion that overlaps with the instantly claimed range. One of ordinary skill in the art would have been motivated to do so because Liu teaches that these are also preferred compositions.
It is noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists (see In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); Titanium Metals Corp. of America v. Banner, 778 F2d 775. 227 USPQ 773 (Fed. Cir. 1985) (see MPEP 2144.05.01). Therefore, the claimed ranges of potassium content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Regarding the catalyst lacking iron(III) compounds, while Example 4 of Liu specifically mentions some Fe(III) content, Liu also teaches that their catalysts may be composed of only ferrous oxide, an iron(II) compound ([0017]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to prepare the catalyst of Liu where the iron compound is only ferrous oxide, and is therefore lacking in iron(III) compounds. One of ordinary skill in the art would have been motivated to do so because Liu teaches that this one of the possible compositions that may be selected for their system.
Regarding the catalyst functioning as a catalyst for ammonia synthesis, it is noted that because the composition taught by Liu is substantially similar to that instantly claimed that it is expected to have the same function. It is further noted that Liu teaches that their composition is able to catalyze the decomposition ammonia to hydrogen , which is the reverse reaction of the ammonia synthesis reaction, and it is well recognized that a composition that is able to catalyze the forward reaction can also catalyze its reverse, as evidenced by Ross (p. 22, Box 1.8).
Regarding claim 20, Liu teaches the catalyst of claim 19, where Liu teaches the potassium being present in the range of 0.2-2.0% by weight ([0045]), which overlaps with the range of 0.8-0.4% by weight required by the instant claim.
It is again noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists. Therefore, the claimed ranges of potassium content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Regarding claims 21 and 23, Liu teaches the catalyst of claim 1, where Liu teaches the that the iron compounds in the catalyst composition consist of wuestite (identified by XRD as mainly FeO), and that the ratio of Fe2+ to Fe3+ is 7.1:1, which corresponds to an overall molecular formula of Fe0.94O, fitting the characterization typical of wuestite, as described in the instant specification (p. 4, lines 29-30). The iron in this composition is therefore considered as being 100% by weight wuestite and therefore also lacks Fe2O3 and Fe3O4.
Regarding claims 21-23, Liu teaches the catalyst of claim 1, where Example 4 of Liu specifically mentions some Fe(III) content, and therefore cannot be considered as lacking iron(III) compounds, as required by claim 22.
However, Liu also teaches that their catalysts may be composed of only ferrous oxide, an iron(II) compound ([0017]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to prepare the catalyst of Liu where the iron compound is only ferrous oxide (FeO, or wuestite where x=0), thereby meeting the limitations of claims 21-23. One of ordinary skill in the art would have been motivated to do so because Liu teaches that this one of the possible compositions that may be selected for their system.
Regarding claim 24, Liu teaches the catalyst of claim 1, where the catalyst is lacking in rare earths ([0017] and [0045]).
Regarding claim 25, Liu teaches the catalyst of claim 1, where the catalyst may contain magnesium, as it does in Example 4, but where magnesium is only an optional component, as it is lacking in Examples 1 and 3 ([0036] and [0042]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify the catalyst of Example 4 to exclude magnesium, thereby arriving at the instant invention. One of ordinary skill in the art would have been motivated to do so because Liu teaches that examples lacking in this additive are also functional catalysts.
Regarding claim 26, Liu teaches the catalyst of claim 1, where the catalyst lacks rare earths ([0017] and [0045]) but may contain magnesium, as it does in Example 4 ([0045]), but where magnesium is only an optional component, as it is lacking in Examples 1 and 3 ([0036] and [0042]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify the catalyst of Example 4 to exclude magnesium, thereby arriving at the instant invention. One of ordinary skill in the art would have been motivated to do so because Liu teaches that examples lacking in this additive are also functional catalysts.
Regarding claims 27 and 28, Liu teaches the catalyst of claim 1, where the catalyst of modified Example 4 consists essentially of the iron compounds and oxides of potassium, calcium, and aluminum, as well as oxides of magnesium, vanadium, and titanium.
However, the magnesium, vanadium, and titanium oxides are not essential features ([0017] and [0022]), and are left out of other embodiments disclosed by Liu, such as Example 1, which consists essentially of the iron compounds and oxides of potassium, calcium, and aluminum ([0036]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify the catalyst of Example 4 to exclude magnesium, vanadium, and titanium, thereby arriving at a composition consisting essentially of the iron compounds and oxides of potassium, calcium, and aluminum. One of ordinary skill in the art would have been motivated to do so because Liu teaches that examples lacking in these other additives are also functional catalysts.
Regarding claim 29, Liu teaches the iron-containing catalyst of claim 19, as analyzed above, wherein modified Example 4 of Liu ([0045]) has potassium, calculated as K2O, present in an amount of 0.2-2.0% by weight, calcium, calculated as CaO, present in an amount 1.5% by weight, and aluminum, calculated as Al2O3, present in an amount of 2.0% by weight, based on the total weight of the catalyst.
The amount of calcium in Example 4 lies within the instantly claimed range of 0.8% to 2.0% by weight, and the preferable amounts of potassium taught by Liu overlap with the instantly claimed range of 0.15% to 0.4%.
Liu also teaches that the amount of aluminum, calculated as Al2O3, can be varied with a preferable range of 0.4%-4% ([0019]), which overlaps with the claimed range of 1.3% to 1.9%.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify catalyst of Liu such that the amount of aluminum in the catalyst composition is anywhere in the range 0.5% to 4.0%, including into the portion that overlaps with the instantly claimed range. One of ordinary skill in the art would have been motivated to do so because Liu teaches that these are also preferred compositions.
It is again noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists. Therefore, the claimed ranges of potassium and aluminum content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Alternatively, Liu also teaches an iron-containing catalyst (Example 6, [0051]) comprising iron compounds at 92.4% by weight and the promoters potassium, calculated as K2O, in an amount of 0.92% by weight, calcium, calculated as CaO, in an amount 1.3% by weight, and aluminum, calculated as Al2O3, in an amount of 1.5% by weight, based on the total weight of the catalyst. The amounts of calcium and aluminum each fall within the instantly claimed ranges, while the amount of potassium lies outside the range for potassium of 0.15% to 0.4% by weight required by the instant claim.
However, Liu also teaches that the preferable range for potassium content spans 0.2% to 2% by weight ([0020]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify catalyst of Liu’s Example 6 such that the amount of potassium amount in the catalyst composition is anywhere in the range 0.2% to 2%, including into the portion that overlaps with the instantly claimed range. One of ordinary skill in the art would have been motivated to do so because Liu teaches that these are also preferred compositions.
It is again noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” a prima facie case of obviousness exists. Therefore, the claimed range of aluminum content merely represents an obvious variant and/or routine optimization of the values of the cited prior art.
Regarding claim 30, Liu teaches the catalyst of claim 29, where the catalyst lacks rare earths ([0017] and [0045]).
Response to Arguments
Applicant's arguments filed 6 February 2026 have been fully considered. Because the example in Xu relied upon as the basis of the prior rejections comprised iron compounds that consisted essentially of iron(III)-containing magnetite, and not wuestite, the prior rejections are withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Liu (CN 109772339 A), as analyzed above.
However, Applicant’s arguments that Xu’s teaching of iron(II) to iron(III) ratios in the range of 0.4-16 excludes materials consisting essentially of wuestite are not persuasive. As recognized in the art and acknowledged in the instant specification, wuestite is an iron oxide of formula Fe1-xO, where x <1/3 and is typically 0.05 to 0.17 (p. 4, lines 29-30 of the instant specification). Charge balance dictates that the content of Fe3+ in wuestite is 2x, while the Fe2+ content is 1-3x, as further supported by Hazen et al. (Reviews of Geophysics and Space Physics, 1984, 22(1), 37-46; p. 1, ¶ 5). It follows then that the ratio of Fe2+ to Fe3+ in a typical wuestite sample is between 8.5:1 (0.85:0.1 for x = 0.05) and 1.44:1 (1.49:0.34, for x = 0.17). Therefore, even a material consisting essentially of wuestite may have significant Fe3+ content.
Applicant’s other arguments regarding Xu, p. 8-9 of the reply, are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Applicant’s arguments regarding unexpected results, p. 10, are relevant to the above rejections presented in this action, but are not persuasive.
Applicant again argues that the relatively low amounts of potassium in combination with the claimed amounts of calcium and aluminum provide an unexpected advantage with regard to catalyst stability and speed of reduction.
However, the evidence relied upon to support this assertion is the data associated with one comparative catalyst, 1e of the instant disclosure. It is again noted that the relatively poor behavior of catalyst 1e compared to the other catalysts in Table 1 cannot be used alone to support the criticality of the claimed potassium range.
In particular, there is no evidence of record to show that it is not the levels of aluminum in catalyst 1e, which notably fall outside the instantly claimed range, that are responsible for this catalyst 1e’s poor performance. Furthermore, the specification indicates that each of catalysts 1a-1l contain further metal oxide promoters (p. 8, lines 8-11) which remain unidentified and may also be responsible for the relative performances of the systems being compared. Additionally, there is also no indication as to what amount of iron compounds exist in catalyst 1e, if they fall within the limits of the amended claim, or if they consist essentially of wuestite. For at least these reasons, the evidence presented is insufficient to rebut the prima facie case of obvious presented by the teaching of overlapping ranges in the prior art. See MPEP 716.02(d).
Conclusion
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/NICHOLAS A. PIRO/Assistant Examiner, Art Unit 1738
/PAUL A WARTALOWICZ/Primary Examiner, Art Unit 1735
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