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 .
Response to Amendment
The amendment filed 07/02/2026 has been entered. Claims 4 and 6 have been canceled by applicant. Claims 1-3, 5, and 7-14 remain pending in the application. Applicant's amendments to the claims have overcome each rejection previously set forth under 35 U.S.C. 112(b) in the non-final office action mailed on 04/29/2026; these rejections are therefore withdrawn.
Response to Arguments
Applicant's arguments filed 07/02/2026 have been fully considered but they are not persuasive.
Applicant argued that Deng, Chubb, and Fosu do not teach the claimed mixing ratio B/A (pages 11-12), along with the other claimed numerical ranges, of amended claim 1. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). In this case, the combination of Parada, Gauthier, Deng, Chubb, and Fosu arrive at the claimed invention. Parada teaches the pressure range (0080), which is relevant to the field of endeavor of Deng, Chubb, and Fosu because Parada teaches a process for producing lithium carbonate from spodumene wherein beta spodumene is subjected to roasting, as taught by Deng, and similarly Gauthier teaches the numerical values for a calcium oxide+mineral mixture (0019) and temperature of water leaching (0029), and further motivates the optimization of a solid-liquid ratio as a result effective variable to control the hydration of calcium oxide as Gauthier teaches (0026). Gauthier is relevant to the field of endeavor as Deng, Chubb, and Fosu because Gauthier also teaches that the method produces lithium hydroxide from spodumene (0015). Therefore such a combination of references would be obvious to one skilled in the art to arrive at the claimed invention.
Applicant argued that Parada is fundamentally different from the water leaching process of the present invention because it is an acid-leaching process with oxygen-rich air (page 13). In response to applicant's argument that Parada is nonanalogous art, it has been held that a prior art reference must either be in the field of the inventor’s endeavor or, if not, then be reasonably pertinent to the particular problem with which the inventor was concerned, in order to be relied upon as a basis for rejection of the claimed invention. See In re Oetiker, 977 F.2d 1443, 24 USPQ2d 1443 (Fed. Cir. 1992). In this case, Parada is reasonably pertinent to the field of endeavor of Deng, because Deng teaches an extra step of acid-leaching, and is otherwise silent on the conditions of parameters that are claimed, and it would be reasonable for one skilled in the art to look to Parada for the teaching of such conditions, since Parada teaches an acid-leaching of spodumene with the necessary specificity of disclosure. Parada teaches air, as claimed, where the claimed invention does not limit the air to non-oxygen-rich air, therefore Parada meets the claimed limitation.
Applicant argued that Gauthier does not teach a technique applied as interrelated conditions in a multi-stage process as in the present invention (page 13). In response to applicant's argument that Gauthier teaches conditions that cannot be applied to a multi-stage process and is therefore not analogous art, this argument is not found convincing because Gauthier teaches a process of obtaining lithium hydroxide from lithium aluminum silicate minerals such as spodumene (0015) which is analogous to the process of obtaining lithium hydroxide from spodumene as Deng teaches, and Gauthier teaches that the process is a multi-stage process with each stage having a taught function, and the numerical ranges having a taught motivation for using such ranges (0019, 0029). Therefore the teachings of Gauthier can be reasonably expected by one skilled in the art to be used as interrelated conditions in a multi-stage process as in the present invention.
Claim Interpretation
Amended claim 1 now recites “(a-2) heat-treating the crushed and pulverized lithium-containing mineral to provide a heat-treated lithium-containing mineral, wherein the heat-treating is carried out at a temperature of from 500 to 1000 C, for 10 minutes to 6 hours, under a gas condition of inputting at least one selected from nitrogen, argon, and air, and a pressure condition of utilizing an atmospheric pressure, and wherein when the lithium-containing mineral is Spodumene (LiAISi2O6), the heat- treating further comprises a phase-transition from an alpha-phase to a beta-phase to provide a phase-transitioned lithium-containing mineral (A)…” The accompanying Remarks describe that the phase transition is an additional treatment (page 9), however, this is not claimed, since the claim language recites that the heat treatment step of (a-2) further comprises a phase transition, rather than that the heat treatment step of (a-2) further comprises an additional heat treatment step. The broadest reasonable interpretation of this limitation is that the step (a-2) of heat treatment contains a phase transition from the alpha-phase to the beta-phase, when the lithium-containing mineral is spodumene, since two separate heat treatment steps in step (a-2) have not been positively claimed.
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 1-3, 5, and 7-14 are rejected under 35 U.S.C. 103 as being unpatentable over Deng et al. 2012 (CN 102838140 A), in view of Chubb 1963 (US 3073673 A), non-patent literature Fosu et al. 2020, Metals 10, no. 10: 1312, Parada et al. 2020 (WO 2020206567 A1), and Gauthier 2022 (CA 3131219 A1), referred to herein as Deng, Chubb, Fosu, Parada, and Gauthier respectively. A machine English translation of the specification of Deng, as provided with this office action, is cited herein.
Regarding claim 1, Deng teaches a method for directly producing environmentally friendly LiOH*H2O from spodumene (0008) through calcination (0011) and water leaching (0014), comprising, as required by the instant claim:
(a-1) crushing and pulverizing the lithium-containing mineral to provide a crushed and pulverized lithium-containing mineral (ball milling of calcined spodumene, 0012, which comprises lithium);
(a-2) heat-treating the lithium-containing mineral to provide a heat-treated lithium-containing mineral (spodumene powder with a mesh size of 80-200 is calcined, 0011), wherein the heat-treating is carried out for 30 minutes (0039), which overlaps with the claimed range of 10 min-6 hrs; as set forth in MPEP 2144.05, in the case where the claimed range "overlap or lie inside ranges disclosed by the prior art," a prima facie case of obviousness exists, In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. 1990);
(a-3) mixing the heat-treated lithium-containing mineral with an alkaline earth metal oxide to provide a mixture (adding quicklime or lime slurry, which is calcium oxide, 0014), water leaching a mixture (“leaching,” mixing with washed water, 0014), followed by solid-liquid separation into a primary lithium water leachate and a primary leach residue (0015);
(a-5) water leaching a calcined primary leach residue (washing with water 1-6 times, 0016), followed by solid-liquid separation into a secondary lithium water leachate and a secondary leach residue (discharging of residue and recycling of washed water, 0016);
and (a-6) recovering lithium from the primary lithium water leachate or the secondary lithium water leachate (leachate of step 5 (0015) is used in steps 6-10 to obtain LiOH*H2O, 0025).
Deng does not teach the order of steps for the following limitations:
Heat-treating the crushed and pulverized lithium-containing material, of step (a-2)
Water leaching the mixture, of step (a-3)
Deng also does not teach the following limitations:
the temperature of step (a-2) ranging from 500 to 1000 C (Deng teaches 1050-1100 C, 0011), and
(a-4) calcining the primary leach residue to provide a calcined primary leach residue.
However, regarding limitations (f) and (g), Chubb teaches an analogous process for producing lithium from spodumene (C1/L10) wherein the lithium-containing material that has been crushed is then heat-treated (Figure 1) and the mixture containing an alkaline earth metal oxide is water-leached (CaO, Figure 1, C2/L17). Generally, the courts have generally held that differences in the order of performing process steps is obvious in the absence of new or unexpected results (see MPEP 2114.04.IV.C.). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as suggested by Deng where ball-milling of the lithium-containing spodumene is conducted before the calcination of the lithium-containing spodumene, for the purpose of selectively pulverizing the beta spodumene, as Chubb teaches (C2/L3-13), in order to separate lithium-containing mineral material from the gangue materials to thus increase lithium yield. Similarly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as suggested by Deng where the addition of quicklime or lime slurry to the lithium-containing spodumene is conducted in an order of the taught process including before the washing with water to make a slurry, for the purpose of obtaining a near-complete extraction, as Chubb teaches (C1/L44), where Chubb further discloses that the presence of calcium advantageously produces valuable by-products (C1/L59). These modifications would have been obvious to one skilled in the art in view of Chubb who teaches that a method with steps in this order results in predictable outcomes, the production of lithium from spodumene minerals.
Regarding limitation (h), Fosu teaches extraction of lithium from mineral ores (abstract) wherein Fosu teaches that spodumene is naturally present in its alpha form, and becomes amenable to lixiviation by calcination at 1000 C to obtain the beta form (bottom of page 1 to page 2). This falls within the claimed temperature range of step (a-2) of 500 to 1000 C. It would be obvious to one skilled in the art to combine the teachings of Deng and Chubb with the teachings of Fosu; one would be motivated to do so because Deng teaches the lixiviation (leaching) of the spodumene with aqueous media (0014) and Fosu teaches that aqueous lixiviation is improved by conversion to the beta form since mobility of the lithium atoms is increased (p 2 pp. 1) and the surface area of beta spodumene is increased which enhances subsequent chemical processing (p. 2 pp. 5, ‘Decrepitation of Spodumene Ore’).
Regarding limitation (i), Fosu teaches the roasting of CaO with spodumene to yield LiAlO2 (page 9 Equation 17, page 12), and further teaches the treatment of CaO with LiAlO2 in the presence of water, to form LiOH (Equations 6 and 27); CaO and LiAlO2 in water meets the limitation of the residue obtained from the first water leaching required by the instant claim. It would be obvious to one skilled in the art to further modify the invention taught by Deng modified by Chubb by calcining the residue obtained after leaching with water, as Fosu teaches because one would be motivated to do so in order to obtain LiOH from any spodumene remaining in the water-leached residue (Equation 27 of Fosu). This modification would predictably increase the yield of the LiOH produced. One of ordinary skill in the art would therefore reasonably arrive at the claimed invention before the effective filing date.
Deng, Chubb, and Fosu are silent regarding the gas and pressure conditions required in the instant claim. As discussed above Deng teaches that the calcination step is performed at 1050-1100℃ (0011) for 30 minutes (0039); this step is therefore capable of performing the function of inducing a phase transition in the spodumene from an alpha-phase to a beta-phase, since Fosu teaches that the phase transition progresses through 800-1100 C (p. 2), and Fosu further teaches that it would be known in the art to treat alpha-spodumene with heat in order to work with beta-spodumene (top of p. 2).
However, Parada teaches a process for producing lithium carbonate from spodumene (0046) wherein beta spodumene is sulfated and subjected to roasting in a rotary furnace 22 with oxygen-enriched air (0067) which is kept at a pressure of 1 atmosphere (0080). Without the disclosure of the conditions necessary for a reaction, one skilled in the art would be motivated to look to knowledge in the art to implement conditions; therefore it would be obvious to one skilled in the art to use the gas atmosphere and pressure conditions taught by Parada to modify the invention of Deng, Chubb, and Fosu and arrive at the claimed invention. One of ordinary skill in the art would be motivated to do so in order to obtain sulfated spodumene, to achieve a more soluble form, as Parada teaches (0021).
Regarding the mass ratio (B/A), temperature, solid-liquid ratio, and reaction time required in step (a-3) when the lithium-containing mineral is Spodumene, Deng teaches a stirring time of 20 minutes (0039); while this falls outside the instant claimed ranges of 0.5 to 12 hours, the range of durations claimed is broad compared to the discrepancy between the 20 minute duration taught by Deng and the lower bound of 0.5 hours, or 30 minutes, claimed. It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as taught by Deng where the duration is optimized near the taught duration, including a duration that falls within the claimed range of durations, in order to sufficiently allow for a reaction to occur, barring evidence of unexpected results of the claimed range. The courts have generally held that a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close; see MPEP Section 2144.05(I), Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). One skilled in the art would therefore arrive at the claimed invention with reasonable expectation of success before the effective filing date of the invention.
Deng, Chubb, Fosu, and Parada do not teach that when the lithium-containing mineral is Spodumene (LiAISi2O6), the water leaching is performed by adding to water a mixture of the phase-transitioned lithium- containing mineral (A) and the metal oxide (B) such that a mass ratio (B/A) is 1 to 6, at a temperature of 25 to 1000C, in a solid-liquid ratio of 1/20 to 1/5. However, Gauthier teaches an analogous method to produce lithium hydroxide from lithium minerals such as spodumene (0015) wherein calcium oxide is present in the oxide-mineral mixture in a mass ratio of between 0.5 and 2.0 (0019). The mixture is calcined (0022) and then leached with water at 70 to 100 degrees Celsius (0029); one of ordinary skill in the art would expect the order of adding water to the mixture, instead of adding the mixture to water as required in the instant claim, to result in no critical difference in order to proceed with the water leaching at 70 to 100 degrees Celsius, since the water leaching step necessarily requires the presence of water and a mixture, and does not depend on the order in which either component is added.
It would be obvious to one skilled in the art to modify the invention taught by Deng with the conditions of mass ratio and temperature of water leaching taught by Gauthier; one would be motivated to do so to control the aluminum-silica bonding present in the by-product, as Gauthier teaches (0019), and to selectively dissolve lithium, potassium, and sodium, as Gauthier teaches (0029). Further, one skilled in the art would be reasonably motivated to optimize the solid-liquid ratio as a result-effective variable to arrive at the claimed range of ratios; one would be motivated to do so in order to fully hydrate calcium oxide, as Gauthier teaches the equilibration of hydration compared to the dehydration of hydroxide (0026) in consideration of the discharge stage reactions taught prior (0025). One skilled in the art would therefore arrive at the claimed invention before the effective filing date.
Regarding claim 2, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 1, and Deng further teaches ball milling to obtain a particle size of 200 mesh, 0012, which corresponds to about 74 microns. It is noted that this ball milling is capable of producing a crushed and pulverized lithium-containing mineral, therefore meeting the limitation of the instant claim.
Regarding claim 3, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 1, and Deng further teaches the use of spodumene (title).
Regarding claim 5, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 1, and Deng further teaches the addition of quicklime or lime slurry, 0039; quicklime being a commonplace name for calcium oxide, this meets the limitation of calcium oxide required by the instant claim.
Regarding claim 7, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 1, and Deng further teaches a leaching rate (lithium oxide concentration in the leachate) of 45 g/L-50 g/L, 0018; this corresponds to a wt.% of about 4.5-5%, falling within the range of 1 wt.% to 35 wt.% required by the instant claim.
Regarding claim 8, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 1, and Fosu further teaches a temperature range for calcination of 100-1300 degrees Celsius (Figure 2) and teaches that the heat-treatment calcination of the LiAlO2-containing residue as taught in Equation 27 has a change in Gibbs free energy below zero (∆G, Figure 2, Eq. 17). Although this temperature range is broader than the instant claimed range of 500 to 1000 C, it has been held that a prima facie case of obviousness exists where claimed ranges “overlap or lie inside ranges disclosed by the prior art;” In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976). Additionally, it has been held that “where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation;” In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as taught by Deng, Chubb, Fosu, Parada, and Gauthier where the temperature is maintained at any workable or optimum range within the taught range, including the claimed range, and arrive at the claimed invention, barring evidence of unexpected results of the claimed range.
Regarding claim 9, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 1; they do not teach that in step (a-5), the water leaching is performed by adding the calcined primary leach residue to water; however, Deng teaches washing with water 1-6 times, 0016. It has been held that differences in the order of performing process steps are obvious in the absence of new or unexpected results (see MPEP 2114.04.IV.C.). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as suggested by Deng, Chubb, Fosu, Parada, and Gauthier where the adding of water is conducted after the mixture is obtained or where the mixture is added after the water is obtained, both for the purpose of contacting the calcined primary leach residue with water as taught by Deng and Fosu.
Regarding the reaction time, Deng teaches a stirring time of 20 minutes, 0039; while this falls outside the instant claimed ranges of 0.5 to 12 hours, the range of durations claimed is broad compared to the discrepancy between the 20 minute duration taught by Deng and the lower bound of 0.5 hours, or 30 minutes, claimed. It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as taught by Deng where the duration is optimized near the taught duration, including a duration that falls within the claimed range of durations, in order to sufficiently allow for a reaction to occur, barring evidence of unexpected results of the claimed range. One skilled in the art would therefore arrive at the claimed invention with reasonable expectation of success before the effective filing date of the invention.
Deng, Chubb, Fosu, and Parada do not teach that step (a-5) is conducted at a temperature of 25 to 100 C, in a solid-liquid ratio of 1/20 to 1/5. However, Gauthier teaches an analogous method to produce lithium hydroxide from lithium minerals such as spodumene (0015) wherein calcium oxide is present in the oxide-mineral mixture, and the mixture is calcined (0022) and then leached with water at 70 to 100 degrees Celsius (0029).
It would be obvious to one skilled in the art to modify the invention taught by Deng with the temperature of water leaching taught by Gauthier; one would be motivated to do so to selectively dissolve lithium, potassium, and sodium, as Gauthier teaches (0029). Further, one skilled in the art would be reasonably motivated to optimize the solid-liquid ratio as a result-effective variable to arrive at the claimed range of ratios; one would be motivated to do so in order to fully hydrate calcium oxide, as Gauthier teaches the equilibration of hydration compared to the dehydration of hydroxide (0026) in consideration of the discharge stage reactions taught prior (0025). One skilled in the art would therefore arrive at the claimed invention before the effective filing date, since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.”
Regarding claim 10, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 1; they do not teach a step (a-7) of calcining the secondary leach residue to provide a calcined secondary leach residue.
However, Fosu teaches the roasting of CaO with spodumene to yield LiAlO2 (page 9 Equation 17, page 12), and further teaches the treatment of CaO with LiAlO2 in the presence of water, to form LiOH (Equations 6 and 27); CaO and LiAlO2 in water meets the limitation of the secondary leach residue obtained from the first water leaching required by the instant claim. It would be obvious to one skilled in the art to modify the invention taught by Deng, Chubb, and Fosu by calcining the residue obtained after leaching with water, as Fosu teaches because one would be motivated to do so in order to obtain LiOH from any spodumene remaining in the water-leached residue, (Equation 27 of Fosu). This modification would predictably increase the yield of the LiOH produced.
Regarding the claimed temperature range of 500 to 1000 C, Fosu teaches a temperature range for calcination of 100 to 1300 degrees Celsius (Figure 2) and teaches that the heat-treatment calcination of the LiAlO2-containing residue as taught in Equation 27 has a change in Gibbs free energy below zero (∆G, Figure 2, Eq. 17). Although this temperature range is broader than the instant claimed range of 500 to 1000 C, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as taught by Fosu where the temperature is maintained at any workable or optimum range within the taught range, including the claimed range, and arrive at the claimed invention, barring evidence of unexpected results of the claimed range.
Regarding claim 11, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 10. They do not teach a step (a-8) of water leaching the calcined secondary leach residue, followed by solid-liquid separation into a tertiary lithium water leachate and a tertiary leach residue, wherein the water leaching is performed by adding the calcined secondary leach residue to water, and at a temperature of 25 to 1000C, in a solid-liquid ratio of 1/20 to 1/5, and for a reaction time of 0.5 to 12 hours.
However, Deng teaches washing with water 1-6 times, 0016. It would have been obvious to perform the water washing as Deng teaches to the calcined secondary leach residue, and arrive at the claimed invention, since Deng teaches that the water washing can be performed more than once (1-6 times, 0016). One of ordinary skill in the art would be motivated to do so in order to further optimize the process to produce lithium hydroxide, as suggested by Deng in avoiding affecting the quality of LiOH produced (0050).
Regarding the reaction time, Deng teaches a stirring time of 20 minutes, 0039; while this falls outside the instant claimed ranges of 0.5 to 12 hours, the range of durations claimed is broad compared to the discrepancy between the 20 minute duration taught by Deng and the lower bound of 0.5 hours, or 30 minutes, claimed. It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as taught by Deng where the duration is optimized near the taught duration, including a duration that falls within the claimed range of durations, in order to sufficiently allow for a reaction to occur, barring evidence of unexpected results of the claimed range. One skilled in the art would therefore arrive at the claimed invention with reasonable expectation of success before the effective filing date of the invention.
Deng, Chubb, Fosu, and Parada do not teach that step (a-8) is conducted at a temperature of 25 to 100 C, in a solid-liquid ratio of 1/20 to 1/5. However, Gauthier teaches an analogous method to produce lithium hydroxide from lithium minerals such as spodumene (0015) wherein calcium oxide is present in the oxide-mineral mixture, and the mixture is calcined (0022) and then leached with water at 70 to 100 degrees Celsius (0029).
It would be obvious to one skilled in the art to modify the invention taught by Deng with the temperature of water leaching taught by Gauthier; one would be motivated to do so to selectively dissolve lithium, potassium, and sodium, as Gauthier teaches (0029). Further, one skilled in the art would be reasonably motivated to optimize the solid-liquid ratio as a result-effective variable to arrive at the claimed range of ratios; one would be motivated to do so in order to fully hydrate calcium oxide, as Gauthier teaches the equilibration of hydration compared to the dehydration of hydroxide (0026) in consideration of the discharge stage reactions taught prior (0025). One skilled in the art would therefore arrive at the claimed invention before the effective filing date, since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.”
Regarding claim 12, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 11. They do not teach a step (a-9) of calcining the secondary leach residue to provide a calcined tertiary leach residue.
However, Fosu teaches the roasting of CaO with spodumene to yield LiAlO2 (page 9 Equation 17, page 12), and further teaches the treatment of CaO with LiAlO2 in the presence of water, to form LiOH (Equations 6 and 27); CaO and LiAlO2 in water meets the limitation of the tertiary leach residue obtained from the water leaching required by the instant claim. It would be obvious to one skilled in the art to modify the invention taught by Deng by calcining the residue obtained after leaching with water, as Fosu teaches. One would be motivated to do so in order to obtain LiOH from any spodumene remaining in the water-leached residue, as Fosu teaches (Equation 27), which would predictably increase the yield of the LiOH produced.
Regarding the claimed temperature range of 500 to 1000 C, Fosu teaches a temperature range for calcination of 100 to 1300 degrees Celsius (Figure 2) and teaches that the heat-treatment calcination of the LiAlO2-containing residue as taught in Equation 27 has a change in Gibbs free energy below zero (∆G, Figure 2, Eq. 17). Although this temperature range is broader than the instant claimed range of 500 to 1000 C, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as taught by Fosu where the temperature is maintained at any workable or optimum range within the taught range, including the claimed range, and arrive at the claimed invention, barring evidence of unexpected results of the claimed range.
Regarding claim 13, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 12. They do not teach a step (a-10) of water leaching the calcined tertiary leach residue, followed by solid-liquid separation into a quaternary lithium water leachate and a quaternary leach residue, wherein the water leaching is performed by adding the calcined tertiary leach residue to water, and at a temperature of 25 to 1000C, in a solid-liquid ratio of 1/20 to 1/5, and for a reaction time of 0.5 to 12 hours.
However, Deng teaches washing with water 1-6 times, 0016. It would have been obvious to perform the water washing as Deng teaches to the calcined tertiary leach residue, and arrive at the claimed invention, since Deng teaches that the water washing can be performed more than once (1-6 times, 0016). One of ordinary skill in the art would be motivated to do so in order to further optimize the process to produce lithium hydroxide, as suggested by Deng in avoiding affecting the quality of LiOH produced (0050).
Regarding the reaction time, Deng teaches a stirring time of 20 minutes, 0039; while this falls outside the instant claimed ranges of 0.5 to 12 hours, the range of durations claimed is broad compared to the discrepancy between the 20 minute duration taught by Deng and the lower bound of 0.5 hours, or 30 minutes, claimed. It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the method as taught by Deng where the duration is optimized near the taught duration, including a duration that falls within the claimed range of durations, in order to sufficiently allow for a reaction to occur, barring evidence of unexpected results of the claimed range. One skilled in the art would therefore arrive at the claimed invention with reasonable expectation of success before the effective filing date of the invention.
Deng, Chubb, and Fosu do not teach that step (a-10) is conducted at a temperature of 25 to 100 C, in a solid-liquid ratio of 1/20 to 1/5. However, Gauthier teaches an analogous method to produce lithium hydroxide from lithium minerals such as spodumene (0015) wherein calcium oxide is present in the oxide-mineral mixture, and the mixture is calcined (0022) and then leached with water at 70 to 100 degrees Celsius (0029).
It would be obvious to one skilled in the art to modify the invention taught by Deng with the temperature of water leaching taught by Gauthier; one would be motivated to do so to selectively dissolve lithium, potassium, and sodium, as Gauthier teaches (0029). Further, one skilled in the art would be reasonably motivated to optimize the solid-liquid ratio as a result-effective variable to arrive at the claimed range of ratios; one would be motivated to do so in order to fully hydrate calcium oxide, as Gauthier teaches the equilibration of hydration compared to the dehydration of hydroxide (0026) in consideration of the discharge stage reactions taught prior (0025). One skilled in the art would therefore arrive at the claimed invention before the effective filing date, since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.”
Regarding claim 14, Deng, Chubb, Fosu, Parada, and Gauthier teach the method as applied to claim 1, and Deng further teaches a leachate containing lithium oxide (0018, containing water, following from 0014, 0015, and 0017). Since claim 14 recites a product (a lithium aqueous solution) performed by the process (the hydrometallurgical method) of claim 1, claim 14 is interpreted as being defined by a product-by-process limitation; "even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself." In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985) Therefore the leachate containing lithium oxide taught by Deng (0018) which is recovered by the method taught by Deng and Fosu meets the limitation of a lithium aqueous solution recovered by the hydrometallurgical method for recovering lithium from the lithium-containing minerals according to claim 1, required by the instant claim.
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 Eileen Moudou whose telephone number is (571)272-1768. The examiner can normally be reached M-Th 8 AM - 4 PM EST.
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, Sally Merkling can be reached at (571)272-6297. 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.
/Eileen Moudou/ Examiner, Art Unit 1738
/MICHAEL FORREST/ Primary Examiner, Art Unit 1738
Prosecution Insights