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 .
Response to Amendment
The Amendment filed October 17th, 2025 has been entered. Claims 1-5, 7, 11-18, 20 and 22-26 remain pending in the application.
Response to Arguments
Applicant's arguments filed October 17th, 2025 have been fully considered but they are not persuasive.
Applicants argue on page 7 of 10 that claim 1 is definite because “reverse flotation” is a term of art. The Examiner notes, however, that the rejection under 35 U.S.C. §112(b) was not based solely on the use of the term “reverse flotation”, but rather on the fact that claim 1 fails to recite any step or mechanism by which a concentrate enriched in iron mineral content is actually produced. Specifically, claim 1 merely recites adding a first amine to an aqueous pulp of ore, while omitting any aeration step, froth formation, froth removal, or recovery step. As written, claim 1 does not specify when or how reverse flotation occurs, not does it explain how silicate is separated or how the iron-enriched concentrate is obtained. The operative flotation steps appear only in claim 2, and are not recited in claim 1. While “reverse flotation may be a known concept, a method claim must nonetheless affirmatively recite the steps that perform the claimed function. In the absence of any flotation step in claim 1, the scope of the claim cannot be reasonably determined, rendering the claim indefinite. Accordingly the rejection of claim 1 under 35 U.S.C. §112(b) is maintained.
Applicants argue on page 8 of 10 that Gefvert (CA-2205885-A1) does not anticipate the claims because it allegedly fails to disclose the specific amine of Formula I, and that reliance on Gefvert would require impermissible “picking and choosing” among embodiments, citing related cases. The Examiner agrees that Gefvert does not expressly disclose the exact amine species recited in Formula I, and accordingly acknowledges that anticipation under 35 U.S.C. §102 is not the appropriate statutory basis. The prior §102 rejection has therefore been withdrawn and replaced with a rejection under 35 U.S.C. §103, which properly addresses the differences between Gefvert and the claimed subject matter. Applicant’s arguments directed to the legal standard for anticipation are therefore moot, as the claims are no longer rejected under §102.
Applicants assert on page 9 of 10 that the secondary reference (Kapiamba) does not cure the alleged deficiencies of Gefvert and refer to earlier arguments regarding amine specificity. However, such arguments are directed to the standard for anticipation under §102 and do not address whether selection of a particular amine species from Gefvert’s disclosed classes would have been obvious under §103. The Examiner notes that claims 24-26 are rejected under 35 U.S.C. §103 because Gefvert teaches amine-based flotation collector compositions, including blends and partially neutralized amines, and that the claimed composition differs only in the selection of particular amine species and ratios. Such differences constitute routine optimization within a known class of flotation collectors and would have been obvious to a person of ordinary skill in the art. Applicant’s arguments do not address this rationale and are therefore unpersuasive.
Applicant’s argument regarding unexpected results is not persuasive. Objective evidence must be commensurate in scope with the claims, yet the data relied upon evaluates only limited specific amine examples under particular test conditions and does not establish that the full scope of Formula I, including all permitted substituent combinations, salts, and mixtures, would exhibit the asserted performance advantage. Moreover, the comparisons are not made against the closest prior art as a whole, as Gefvert discloses a broad class of structurally similar amine collectors used for flotation of iron ore under the same operating conditions. Further, Gefvert expressly teaches that flotation performance varies with amine structure, chain length, substitution, and degree of neutralization, and that such parameters are routinely adjusted to optimize selectivity and recovery. Accordingly, any performance differences shown for particular amine species represent predictable results of routine optimization, rather than unexpected properties. Applicants have also failed to establish a clear nexus between the alleged results and the full scope of the claimed invention.
Claim Rejections - 35 USC § 112
Claims 1-5, 7, 11-18, and 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.
Regarding claim 1, the claim is directed to a method for manufacturing a concentrate enriched in iron mineral content from an ore, which contains an iron mineral and silicate, by a reverse flotation. However, it has not been made clear in the claim at which step or by what means a concentrate enriched in iron mineral content from an ore, which contains an iron mineral and silicate, has been manufactured by a reverse flotation. Claims 2-5, 7, 11-18 and 20 are rejected due to their dependency upon claim 1.
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 (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 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-5, 7, 11-18, 20 and 22-26 are rejected under 35 U.S.C. 103 as being unpatentable over Gefvert (CA-2205885-A1).
Regarding claim 1, Gefvert discloses a method for manufacturing a concentrate enriched in iron mineral content from an ore (Gefvert claim 1 “method of separating impurities from ore” and abstract discloses removal of impurities from iron ore which would produce a concentrate enriched iron mineral content), which contains an iron mineral and silicate (Gefvert p. 15 par. 1), by a reverse flotation (Gefvert claim 1 “froth flotation”), the method comprising: adding a first amine (Gefvert p. 7 par. 3 discloses varieties of alkyl diamines added to promote flotation) to an aqueous pulp of the ore, wherein the aqueous pulp was prepared by addition of water to the ore, and wherein optionally one or more flotation auxiliaries are added to the aqueous pulp and/or with the first amine, to obtain an aqueous mixture (Gefvert claim 1 “slurry comprising said ore, water, optional froth flotation additives, and a composition of matter formed by blending”).
Gefvert does not expressly disclose wherein the first amine is a compound of formula I
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wherein R1 and R2 are independently from each other methyl, ethyl, propyl, I-methyl-ethyl, butyl, pentyl, hexyl, heptyl or 2-methyl-hexyl, a salt of a protonated compound of formula I and a first anion or a mixture thereof.
However, Gefvert teaches reverse cationic froth flotation of iron ore to remove siliceous impurities, wherein finely divided iron ore is slurried in water, amine collectors are added, air is injected to form a froth containing siliceous gangue, and the iron-rich material remains in the slurry and is recovered as concentrated (Gefvert abstract, p. 1-2, 15-18, claims 1-7). Gefvert further teaches that the amine collector may be selected from alkyl amines, alkyl diamines, alkyl polyamines, ether amines, and ether polyamines, including primary, secondary, and tertiary amines, and that such amines may be partially or fully neutralized with carboxylic acids to form salts to improve dispersibility and performance at high pH (Gefvert (p. 8-9). Gefvert explicitly teaches that alkyl diamines and ether amines having defined alkyl substituents are effective collectors for siliceous gangue in iron ore flotation and that selection of chain length, branching, and degree of neutralization is a matter of optimization depending on performance goals such as selectivity, dispersibility and recovery (Gefvert p. 6-10, 15-18). Although Gefvert does not expressly exemplify the exact diamine structure of formula I in the manner of claim 1, Gefvert does disclose “Preferred alkyl diamines useful in the present invention include those having the formula (R6)(R7)N(CH2)2-3N(R8)(R9) wherein each of R6, R7, R8 and R9 is alkyl containing 1 to 30 carbon atoms, and preferably alkyl containing 4 to 20 carbon atoms. Also, the groups R6-9 can be linear, branched, cyclic, or aromatic (especially phenyl). Moreover, any of R7, R8 and/or R9 can be hydrogen.” (Gefvert p. 7 par. 3) teaching a finite and predictable class of amine collectors, including such diamines having alkyl substituents within overlapping carbon-number ranges, used for the same purpose (reverse flotation of iron ore) under the same operating conditions.
It would have been obvious to one of ordinary skill in the art prior to the effective
filing date of the claimed invention to select the particular diamine species within Gefvert’s disclosed amine classes, such as a diamine having the alkyl substituents as recited in claim 1. It would have been an obvious matter or routine optimization for a person of ordinary skill in the art seeking to balance collector strength, selectivity, solubility, and froth behavior, especially in view of Gefvert’s explicit teaching that amine structure and substitution affect flotation performance and are adjusted based on ore characteristics and process conditions.
Regarding claim 2, Gefvert discloses the method according to claim 1, further comprising: a) providing the ore, which contains an iron mineral and silicate (Gefvert claim 1 requires first providing the ore to prepare a slurry of it), b) preparing from the provided ore by addition of water and optionally one or more flotation auxiliaries an aqueous pulp (Gefvert claim 1), c) adding the first amine to the prepared aqueous pulp of the ore (Gefvert claim 1 and p. 7 par. 3) and optionally one or more flotation auxiliaries to obtain an aqueous mixture (Gefvert p. 15 par. 2), d) aerating the aqueous mixture in a flotation cell to generate a froth (Gefvert p. 15 par. 2), which is enriched in silicate content (Gefvert p. 15 par. 1), and removing the generated froth from the flotation cell (Gefvert p. 15 par. 2), and e) obtaining from the flotation cell the concentrate enriched in iron mineral content (Gefvert p. 16 par. 1 iron ore processing described leaves enriched iron ore beneficiated in the pulp).
Regarding claim 3, Gefvert discloses the method according to claim 1, wherein at (c) a second amine is further added (Gefvert claim 2 describes the amine component comprises “one or more compounds”), wherein the second amine is a compound of formula II
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, wherein R3 is a C5-C17 alkyl, which is branched or linear, or a C5-C17 alkenyl, which is branched or linear, a salt of a protonated compound of formula II and a second anion or a mixture thereof, or wherein is a C7-C12 alkyl, which is branched or linear, or wherein R3 is 1-ethyl-pentyl (Gefvert claim 2 discloses overlapping varieties of the alkyl amines described where the n of Gefvert is 1).
Regarding claim 4, Gefvert discloses the method according to claim 1, wherein R1 and R2 are independently from each other methyl, ethyl, propyl, 1-methyl-ethyl, butyl or pentyl (Gefvert p. 7 par. 3 discloses these options where R6 and R7 corresponding to R1 and R2 but must include the additional CH2 group prior to R1 and R2, are preferably alkyl containing 1 to 30 carbon atoms and may be linear, branched, etc.).
Regarding claim 5, Gefvert discloses the method according to claim 1, wherein R1 and R2 are the same (Gefvert p. 7 par. 3 provides varieties in which these R groups are identical).
Regarding claim 7, Gefvert discloses the method according to claim 1, wherein R1 and R2 are propyl (Gefvert p. 7 par. 3 the variety in which R8 and R9 are both hydrogen and R6 and R7 are both butyl and the alkyl chain between the nitrogen atoms is a 3-carbon chain discloses this compound specifically).
Regarding claim 11, Gefvert discloses the method according to claim 1, wherein the first anion is C1-C18 carboxylate (Gefvert claim 1 includes the step of adding a variety of acids of which a linear carboxylic acid containing 3 to 24 carbons are listed for the purpose of neutralizing the amines [abstract and p. 3 par. 2 and others] which will form the carboxylate), fluoride, chloride, bromide, iodide, sulfonate, hydrogen sulfate, sulfate, dihydrogenphosphate, hydrogen phosphate, phosphate, nitrate, hydrofluorosilicate, fluorosilicate or a mixture thereof.
Regarding claim 12, Gefvert discloses the method according to claim 3, wherein the second anion is C1-C18 carboxylate (Gefvert claim 2 “and mixtures thereof”), fluoride, chloride, bromide, iodide, sulfonate, hydrogen sulfate, sulfate, dihydrogen phosphate, hydrogen phosphate, phosphate, nitrate, hydrofluorosilicate, fluorosilicate or a mixture thereof.
Regarding claim 13, Gefvert discloses the method according to claim 1, wherein the first amine (A) is added in an amount in the range from 10 g to 500 g per ton of the ore (Gefvert p. 2 par. 3 discloses the overlapping range of 0.02-2 pounds per ton or ore which corresponds to 9.07 to 907.18 grams).
Regarding claim 14, Gefvert discloses the method according to claim 3, wherein the sum of the weights of the first amine (A) and of the second amine (B) (Gefvert claim 2 describes the amine component comprises “one or more compounds”) is added in an amount in the range from 10 g to 500 g per ton of the ore (Gefvert discloses the amount of amine added on p. 2 par. 3 which applies to the sum of any combination of amine).
Regarding claim 15, Gefvert discloses the method according to claim 1, wherein the pH value at (c) is between 8 and 12 (Gefvert discloses the “pH regulators for adjusting pH of the ore slurry to the desired level to obtain optimum utility from the additives mentioned” and p. 4 par. 2 indicates the pH should be between 10.5 to 11).
Regarding claim 16, Gefvert discloses the method according to claim 1, wherein the ore contains iron atoms in the range of 20 wt.% to 55 wt.% (Gefvert example 4 on p. 17 “35 wt. %”) based on the weight of the ore.
Regarding claim 17, Gefvert discloses the method according to claim 1, wherein all iron minerals in the ore are non-sulfidic iron minerals (Gefvert p. 17 example 4 “hematite” is a non-sulfidic iron mineral).
Regarding claim 18, Gefvert discloses the method according to claim 1, wherein the iron mineral in the ore contains an iron oxide, or wherein the iron mineral contains hematite (Gefvert p. 17 example 4), magnetite or goethite or a mixture of two or three thereof.
Regarding claim 20, Gefvert discloses the method according to claim 1, wherein at (b) one or more flotation auxiliaries are added and one of the flotation auxiliaries is a depressing agent, a froth regulator (Gefvert p. 15 par. 3 “frothers, which promote the formation of the froth”), a co-collector or an extender oil, optionally, wherein a depressing agent is added as a flotation auxiliary and the depressing agent is a starch.
Regarding claim 22, Gefvert discloses a method of using a first amine (Gefvert claim 1) as a flotation collector (Gefvert p. 15 par. 2) for manufacturing a concentrate enriched in iron mineral content from an ore (Gefvert claim 1 “method of separating impurities from ore” and abstract discloses removal of impurities from iron ore which would produce a concentrate enriched iron mineral content), comprising: combining the first amine with the ore to form a combination (Gefvert claim 1 “slurry”), wherein the ore comprises an iron mineral and silicate (Gefvert p. 15 par. 1); performing a reverse flotation process using the combination to form the concentrate (Gefvert claim 1 “froth flotation”), wherein the first amine is a compound of formula I (Gefvert discloses varieties of the alkyl diamines described here on p. 7 par. 3), a salt of a protonated compound of formula I (Gefvert claim 1 also includes the addition of a carboxylic acid which would protonate and form a salt of the first amine) and a first anion (Gefvert claim 1 a carboxylate is formed as part of the salt) or a mixture thereof as defined in claim 1.
Regarding claim 23, Gefvert discloses a method of claim 22, wherein a combination of the first amine (A) and a second amine (B) is used (Gefvert claim 2 describes the amine component comprises “one or more compounds”) as the flotation collector and the second amine (B) is a compound of formula II (Gefvert claim 2 discloses varieties of the compounds described), a salt of a protonated compound of formula II or a mixture thereof as defined in claim 3.
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 (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 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 24-26 are rejected under 35 U.S.C. 103 as being unpatentable over Gefvert (CA-2205885-A1) in view of Kapiamba, "The effects of partially replacing amine collectors by a commercial frother in a reverse cationic hematite flotation".
Regarding claim 24, Gefvert discloses a non-adhesive composition for a use as a flotation collector, comprising: a first amine, which is a compound of formula I
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,
wherein R1 and R2 are independently from each other methyl, ethyl, propyl, 1-methyl-ethyl, butyl, pentyl, hexyl, heptyl or 2-methyl-hexyl, a salt of a protonated compound of formula I and a first anion or a mixture thereof, and a second amine, which is a compound of formula II
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,
wherein R3 is a C5-C17 alkyl, which is branched or linear, or a C5-C17 alkenyl, which is branched or linear, a salt of a protonated compound of formula II and a first anion or a mixture thereof.
Gefvert does not disclose wherein the weight ratio between the first amine and the second amine is in a range from 0 .2 to 1.
Kapiamba discloses that use of amine collectors in iron ore concentrators act as both collector and frother (Kapiamba p. 1 rt. col par 2). Kapiamba discloses that the partial replacement of a portion of the amine compounds by a commercial frother improves the efficiency of the system (Kapiamba p. 2 left col. par. 1) demonstrating that knowledge of tuning froth flotation systems by adjusting the ratio of reagents used in the process is well known within the art. Further, Kapiamba continues by demonstrating that the ratio of the reagents is critical as replacement by half improved recovery but a 75% replacement showed a performance decline (Kapiamba p. 2 rt. col. par 2). This discloses that the ratios of the reagent additives used in froth flotation are a result effective variable that should be optimized.
It would have been obvious to one of ordinary skill in the art at the time of filing to combine the teachings of Kapiamba with the method of Gefvert to optimize the performance by adjusting the weight ratio between the first amine and the second amine is in a range from 0 .2 to 1. There was a reasonable chance for success as use of amine collectors is well known within the art and there would have been motivation to do so as it would have resulted in improved performance while saving unnecessary costs on reagents used in excess without any improvement otherwise.
Regarding claim 25, Gefvert discloses the composition according to claim 24, wherein the composition is water-soluble (the composition of claim 24 comprises a mixture of ionic materials which are inherently water soluble).
Regarding claim 26, Gefvert discloses the composition according to claim 24, wherein the sum of the weights of the first amine (A) and of the second amine (B) is in the range from 50 wt.% to 100 wt.% based on the overall weight of the composition (Gefvert discloses on p. 8 par. 2 that the amount of acid can vary greatly from 2 percent up to 100 percent which would overlap with the range of 50 to 100 wt. %).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to WILLIAM ADDISON GEISBERT whose telephone number is (703)756-5497. The examiner can normally be reached Mon-Fri 7:30-5:00 EDT.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Bobby RAMDHANIE can be reached at (571)270-3240. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/W.A.G./Examiner, Art Unit 1779
/Bobby Ramdhanie/Supervisory Patent Examiner, Art Unit 1779
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