Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election Acknowledged/Status of Application
Applicant's election with traverse of the species lanthanum encompassing claims 1-11 in the reply filed on 8/11/2026 is acknowledged. The traversal is on the ground(s) that the species requirement was improperly issued under PCT Rule 13.1 when it should have been issued under US rules. Applicant’s argument is acknowledged but not seen as mitigating as election would be necessitated under standard US practice. As such, the requirement for species election is maintained.
Claims 1-11 are pending, claims 8-10 are withdrawn as being directed to nonelected species and claims 1-7 and 11 are presented for examination on the merits.
The following rejections are made.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 7/16/2025 was considered by the examiner.
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.
Claims 1, 6, 7 and 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al. (ACS, Applied Materials and Interfaces, 2013, 5, 9719-9725) in view of Chen et al. (CN 105152192; of record).
Lin teaches a method utilizing nano-Mg(OH)2 for the removal of rare earth elements (REE) (e.g. terbium, cerium, etc.; see page 9720) from wastewater (see abstract) wherein the nano-Mg(OH)2 are in the form of nanoplatelets (see page 9721). Magnesium ions of the nano-Mg(OH)2 are replaced by the REE in the wastewater via cation exchange reaction between nano-Mg(OH)2 and the REE from the magnesium hydrate nanosheet surface to internal layer by layer (see abstract and page 9722). Once the deposited REE layer reaches a certain thickness, the exchange process stops (see page 9722). The outcome of the exchange process results in a core-shell structure wherein Mg(OH)2 remains at the core and the REE hydroxide is deposited as a polycrystalline layer (i.e. monolayer) on the surface of the nano-Mg(OH)2 nanoplatelet (see Scheme 1, page 9723; see instant claim 1). The polycrystalline REE surface is understood to possess many individual crystals (crystallites) so as to produce the polycrystalline surface (see instant claim 6). The mechanism of REE ion exchange yields a self-assembled monolayer shell which produces a REE hydroxide layer (see ‘uptake mechanism’ page 9722). Lin’s method occurs in a packed column but further separating the REE exchanged nano-Mg(OH)2 is contemplated (see page 9270) (both of which read on sequestering the REE exchanged nano-Mg(OH)2).
Lin’s method fails to teach the remove wastewater metal as being the REE lanthanum (per species election filed 8/11/2026).
Chen, like Lin, is directed to the use of magnesium hydroxide for isolating REEs thereby producing a Mg(OH)2 core/REE shell nanocomposite (see page 1). Chen’s method provides magnesium hydroxide in water which forms a concentration gradient layer of OH ions on the surface that enables rare earth metal hydroxide (see instant claims 1 and 11) to nucleate on the magnesium hydroxide surface thereby forming a rare earth shell disposed around the magnesium hydroxide core (see page 3). Chen teaches that the magnesium hydroxide acts as a template and that precipitation occurs on the surface conversion reaction whereby cation exchange occurs between the magnesium hydroxide and the rare earth metal (see page 2). Exemplified rare earth metals for cation exchange with magnesium include metals such as lanthanum, terbium and cerium (see page 3 and Example 4). Given the overlap between Li and Chen, it would have been an obvious to utilize Lin’s nano-Mg(OH)2 in the process of isolating lanthanum as the nano-Mg(OH)2 is identified as capable of isolating other similar lanthanide-series rare earth metals (e.g. terbium, cerium, etc.).
Regarding instant claim 11, the combined method of Lin and Chen would suggest that the REE metals and the magnesium would need to be in stoichiometric ratio sufficient to enable the exchange of the REE for the magnesium cation at the surface layer. Lin teaches that the magnesium and lanthanide metal terbium be present in a molar ratio of 3:2 (see page 9721). Similarly, Chen describes their process as having a stoichiometric (i.e. molar) ratio suitable for carrying forward the exchange process. Both references together suggest that the surface magnesium and the metal ions therefore be in a molar ratio sufficient to enable cation exchange which is presumed to be ‘balanced’ per instant claim 11. As to the coverage of the magnesium hydroxide core being from 1-99%, this is considered obvious in view of Scheme 1 proposed by Lin:
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(page 9723) which depicts the majority of the nanoplatelet surface occupied with terbium cation. Additionally, this parameter would be sought to be maximized so as to recover the greatest amount of REE.
Therefore, the invention as a whole is prima facie obvious to one of ordinary skill in the art at the time the invention was filed, as evidenced by the references, especially in absence of evidence to the contrary.
Claims 2 and 3 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al. (ACS, Applied Materials and Interfaces, 2013, 5, 9719-9725) in view of Chen et al. (CN 105152192; of record) as applied to claims 1, 6, 7 and 11, further in view of Joshi et al. (US 2013/0287653).
Lin and Chen fail to teach the method as treating water that has been exposed to fly ash or mine tailings.
Joshi teaches methods of removing REE (e.g. lanthanum, cerium, etc.; see [0025]) from coal ash, e.g. fly ash (see [0004]). It is taught that the removing REE from fly ash is economical and energy efficient (see [0006]). Thus, it would have been obvious to use the method of Lin and Chen on aqueous fly ash mixtures so as to remove the desired REE therefrom. See MPEP 2143(I)(D) that states applying a known technique to a known product ready for improvement to yield predictable results is supportive of obviousness.
Therefore, the invention as a whole is prima facie obvious to one of ordinary skill in the art at the time the invention was filed, as evidenced by the references, especially in absence of evidence to the contrary.
Claim 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al. (ACS, Applied Materials and Interfaces, 2013, 5, 9719-9725) in view of Chen et al. (CN 105152192; of record) as applied to claims 1, 6, 7 and 11, further in view of Hodges et al. (US 4240886).
Chen and Lin fail to teach sequestering the REE by electrowinning or thermal reduction.
Hodges teaches that electrowinning is an extractive metallurgic known for its stability and stable electrical energy requirements. The process applies an electric current, via anode and cathode, to a solution comprising target metal ions so as reduce those ions causing their deposition on the electrode and then recovering the reduced metal (see abstract and claim 1).
Lin teaches eluting the REE (as a cation) from the nano-Mg(OH)2 nanoplatelet surface by adjusting the pH but fails to describe a process by which the REE metal itself is purified and isolated. It would have been obvious to use the electrowinning method of Hodges on the cationic REE eluent so as to reduce the ions and cause their deposition in order to enable their recovery. See MPEP 2143(I)(C).
Therefore, the invention as a whole is prima facie obvious to one of ordinary skill in the art at the time the invention was filed, as evidenced by the references, especially in absence of evidence to the contrary.
Claim 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al. (ACS, Applied Materials and Interfaces, 2013, 5, 9719-9725) in view of Chen et al. (CN 105152192; of record) as applied to claims 1, 6, 7 and 11, further in view of Maddan et al. (US 7892447; of record).
Lin teaches that their Mg(OH)2 nanoplatelet has a crystallite size of 16.9 nm in the [001] direction and 22.1 nm in the [101] direction (see page 9720).
However, Lin fails to teach the platelet having a diameter of 30-3500 nm, a thickness of 1-400 nm and an aspect ratio of 15-75.
Maddan describes a metal hydroxide and metal oxide nanoplatelets wherein the nanoplatelet has a diameter of 30-3500 nm, a thickness of 1-400 nm and an aspect ratio of 15-70 (see page 2, lines 25-43). Exemplified metal hydroxides and oxides include metals other than magnesium such as barium, zirconium, vanadium, iron, aluminum and copper (see page 1, lines 45-55) (see instant claims 10 and 12). Although Mg(OH)2 is not contemplated Maddan, the dimensions described by Maddan would have been obvious to employ for the nanoplatelet of Lin with a reasonable expectation for success in methods REE cation exchange. Moreover, see MPEP 2144.04(IV)(A) which states that changes in size are not considered inventive.
Therefore, the invention as a whole is prima facie obvious to one of ordinary skill in the art at the time the invention was filed, as evidenced by the references, especially in absence of evidence to the contrary.
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.
Claims 3, 4, 6 and 11 is rejected under 35 U.S.C. 112(b) as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor regards as the invention.
Claim 3, dependent from claim 1, recites “…wherein the method is a method o mining the metal or the rare earth.” This limitation is unclear because claim 1 is a “method of removing ions or a metal…” It appears that claim 5 is attempting to shift the scope of claim 1 from ‘removing ions of a metal’ to ‘a method of mining the metal or the rare earth’. It is unclear how exactly claim 3 is to be limiting of the method of claim 1. Clarification is requested.
Claim 4, dependent from claim 1, recites “…wherein the resulting nanoplatelets having a metal hydroxide layer are further subjected to electrowinning or thermal reduction to recover the sequestered metal ions.” The limitation to ‘sequestered metal ions’ lacks sufficient support as claim 1 never contemplates metal ions being sequestered. Instead, claim 1 requires that the nanoplatelet as a whole be sequestered. The nanoplatelet is not considered equivalent to a metal ion. Clarification is requested.
Claim 6 recites, “wherein the metal hydroxide monolayer nanoplatelet comprises an individual crystallite.” What is ‘individual’ meaning in this claim? It is unclear if this means that a single crystalline phase comprises the shell or a single crystalline structure comprises the crystallite or something else. Clarification is requested.
Claim 11, dependent from claim 1, recites, “…wherein the molar content of the outer layer of the core to a stoichiometric balanced molar content of the ions to produce a shell providing from about 1% to 99% coverage of the core with individual metal ions or mixed metal ions.” This claim is unclear because:
a) what is the outer layer? claim 1 does not recite an outer layer and thus this limitation lacks antecedent basis;
b) what does stoichiometrically balanced mean? The metes and bounds of the limitation are not defined so as to know what “molar content” would be considered infringing? There is no guidance conveying what stoichiometrically balanced encompasses and so this limitation is indefinite; and
c) what are “the ions” which produce a shell? It is presumed to be the metal ions of claim 1 but still yet “the ions” are not clearly defined with respect to claim 1. Given the ambiguity, clarification is required.
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.
Claim 4 is rejected under 35 U.S.C. 112(d) 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.
Claim 4, dependent from claim 1, recites, “…wherein the method is a method of mining the metal or the rare earth.” Claim 1 however is to a “method of removing ions of a metal other than magnesium, or rare earth ions, from a substance…”. Claim 4 fails to further limit claim 1 as it expands the scope from a “method of removing ions of a metal… from a substance” to a “method of removing ions of a metal… from a substance and a method of mining the metal or rare earth”. Claim 4 therefore does not further limit claim 1.
Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KYLE A PURDY whose telephone number is (571)270-3504. The examiner can normally be reached from 9AM to 5PM.
If attempts to reach the examiner by telephone are unsuccessful, the examiner's supervisor, Bethany Barham, can be reached on 571-272-6175. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/KYLE A PURDY/Primary Examiner, Art Unit 1611
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