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 15 October 2025 has been entered. Claims 1, 3-5, and 7 are amended. Accordingly, claims 1-7 remain pending in the application. Applicant’s amendments to the claims have overcome each and every 112(b) rejection previously set forth in the Non-Final Office Action mailed 7 August 2025.
Claim Objections
Claim 1 is objected to because of the following informalities:
Claim 1, lines 25-26, "and introducing nitrogen protection on the solid-liquid mixture, and introducing a nitrogen protection;" should read "and introducing nitrogen protection on the solid-liquid mixture;"..
Appropriate correction is required.
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.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-7 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.
Claim 1, lines 33-34, recite “the anhydrous lithium iodide has…less impurity content”. It is unclear what the impurity content is less than.
Claims 2-7 are indefinite as they depend from an indefinite base and fail to cure the deficiencies of the base claim.
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.
Claims 1-7 are rejected under 35 U.S.C. 103 as being unpatentable over Wang (CN 102229435) in view of Wang (CN 104261440) and Miki (JP 2004035302) and Garikipati (US 2014/0275465) and Guo (CN 104671211) and Riedel (CN 1089771).
Regarding Claim 1, Wang ‘435 discloses a method of preparing anhydrous lithium iodide (claim 1, step 2), comprising: reacting lithium hydroxide (claim 1, step 1.1), specifically lithium hydroxide monohydrate (lithium hydroxide monohydrate meets the limitation of an industrial grade lithium hydroxide monohydrate; pg. 3, par. 2) with a hydroiodic acid with a reaction temperature between 30-70°C (30-70°C meets the limitation of under a condition of not exceeding 80°C; claim 1, step 1.1). Wang ‘435 further discloses heating to 80-150°C under the condition of -0.1 MPa (claim 1, step 1.4).
Regarding the heating temperature in the lithium trihydrate preparation step in claim 1, it appears that 80-150°C taught by Wang ‘435 overlaps the claimed range of 90-110°C such that the range taught by Wang ‘435 obviates the claimed range. See MPEP 2144.05 (I).
Regarding the pressure in the lithium trihydrate preparation step in claim 1, it appears that -0.1 MPa taught by Wang ‘435 is close to the claimed range of a negative pressure of 0.075-0.09 MPa such that the range taught by Wang ‘435 obviates the claimed range. See MPEP 2144.05 (I).
Wang ‘435 further discloses cooling the product to obtain a lithium iodide white yellow crude product (claim 1, step 1.5), specifically, a solid crude product (obtaining lithium iodide solid meets the limitation of removing water and crystallizing; claim 1, step 1.5). Wang ‘435 further discloses dissolving lithium iodide crude product in an organic solvent and stirring (claim 1, step 2.1), wherein the organic solvent may be an alcohol (claim 2), and wherein the alcohol may be ethanol (claim 3), which would necessarily produce a lithium iodide ethanol solution.
Wang ‘435 is silent to obtaining a lithium iodide trihydrate as well as a mass ratio of lithium iodide trihydrate in ethanol.
Wang ‘440 discloses a method of preparing an anhydrous lithium iodide, comprising: mixing lithium hydroxide monohydrate and hydroiodic acid and evaporating to obtain solid lithium iodide trihydrate, mixing the lithium iodide trihydrate with an organic solvent in a mass ratio of 1:5 to 1:1 (pg. 2, par. 2), wherein the organic solvent may be ethanol (pg. 2, par. 5).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Wang ‘440 to provide a step for obtaining lithium iodide trihydrate and dissolving the lithium iodide trihydrate in absolute ethanol in a 1 : 1-5 mass ratio under stirring to obtain a lithium iodide ethanol solution, because obtaining lithium iodide trihydrate and dissolving in ethanol at a mass ratio of 1:1-5 are process parameters well-known in the art of preparing an anhydrous lithium iodide, as recognized by Wang ‘440.
Wang ‘435 further discloses adding hydroiodic acid to the lithium iodide organic solvent solution, which necessarily would adjust a pH of the solution (claim 1, step 2.1). Wang ‘435 also teaches adjusting pH with lithium hydroxide or hydroiodic acid (claim 1, step 1.2), and because the two methods were art recognized equivalents at the time the invention was made, one of ordinary skill in the art would have found it obvious to substitute the hydroiodic acid for the lithium hydroxide.
Wang ‘435 further discloses filtering to remove impurities (claim 1, step 2.2).
Wang ‘435 is silent to filtering via membrane filtration.
Miki discloses removing solid impurities from an aqueous solution containing an alkali metal halide (lithium iodide is an alkali metal halide) by filtration under reduced pressure using a membrane filter [0026].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Miki to remove impurities through a membrane filtration device equipped with a membrane element because filtering with a membrane device is a process parameter well-known in the art of removing impurities from a solution containing alkali metal halides, as recognized by Miki.
Miki is silent to the pressure the membrane filter is under.
Garikipati discloses using nanofiltration (nanofiltration is a form of membrane filtration) to remove impurities operated at a pressure of 70-700 psi [0071], which is approximately 0.5-4.8 MPa.
Regarding the filter pressure in claim 1, it appears that 0.5-4.8 MPa taught by Garikipati overlaps the claimed range of 0.1-3.0 MPa such that the range taught by Garikipati obviates the claimed range. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Miki and Garikipati to remove impurities through a membrane filtration device equipped with a membrane element under a pressure of 0.1-3.0 MPa, because performing membrane filtration at a pressure of 0.1-3.0 MPa is a process parameter well-known in the art of membrane filtration, as recognized by Garikipati.
Wang ‘435 is silent to adjusting pH of the lithium iodide ethanol solution after filtration.
Wang ‘435, however, teaches two pH adjustment steps by adding lithium hydroxide or hydriodic acid (claim 1, step 1.2 and 2.1).
Guo discloses it is recommended to adjust the pH value of the obtained alkali metal iodide with an alkali metal hydroxide for quality stability and product safety [0126].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Guo to provide an additional pH adjustment step after filtration as Wang ‘435 teaches two pH adjustment steps (claim 1, step 1.2 and 2.1), and it is recommended to adjust the pH value of the obtained alkali metal iodide with an alkali metal hydroxide for quality stability and product safety, as recognized by Guo [0126].
Wang ‘435 further discloses distillation of the lithium iodide ethanol solution (aka the mother liquor obtained after filtration) under a pressure of -0.1 MPa, raising the temperature to 150-300°C (claim 1, step 2.3) to obtain a solid of anhydrous lithium iodide (claim 1, step 2.4). Continuously distilling ethanol and water until a water content in the lithium iodide ethanol solution is reduced is necessarily present as Wang ‘435 teaches a solid of anhydrous lithium iodide following distillation (claim 1, step 2.4). Wang ‘435 further discloses the glove box wherein distillation takes place is filled with high-purity nitrogen (nitrogen is an inert gas; claim 1, step 2.1), such that Wang ‘435 meets the limitation of keeping the lithium iodide ethanol solution under the protection of a dry inert gas during distillation.
Regarding the pressure during distillation in claim 1, it appears that -0.1 MPa taught by Wang ‘435 is close to the claimed range of a negative pressure of 0.08-0.09 MPa such that the range taught by Wang ‘435 obviates the claimed range. See MPEP 2144.05 (I).
Regarding the temperature during distillation in claim 1, it appears that 150-300°C taught by Wang ‘435 overlaps the claimed range of 145-160°C such that the range taught by Wang ‘435 obviates the claimed range. See MPEP 2144.05 (I).
Wang ‘435 is silent to using azeotropic distillation and passing the distilled ethanol and water through a drying tube to absorb the distilled water, returning the distilled ethanol to the lithium iodide ethanol solution. Wang ‘435 is further silent to a water content in the lithium iodide ethanol solution after distillation.
Guo discloses a method of preparing anhydrous alkali metal iodide (lithium iodide is an alkali metal iodide; [0032]). Guo further discloses alcohols are used as solvents in the reaction process [0051]. Guo further discloses azeotropic distillation for removing water from alcohol, and the alcohol can be added back into the solution to achieve the dehydration effect of the alkali metal iodide [0071]. Guo further discloses alcohol is dehydrated using a desiccant (dehydrating alcohol using a desiccant meets the limitation of passing the distilled ethanol and water through a drying tube to absorb the distilled water; [0072]. Guo further discloses a zeolite can be used as desiccants that physically absorb moisture, and the most typical zeolite is molecular sieve [0069], such that the desiccant of Guo meets the limitation of a drying tube (see claim 6 of the present application). Guo further discloses a water content in the alcohol solution of alkali metal iodide during the dehydration process to be less than 0.5 weight % [0068]. Guo further discloses the dehydration process results in an ideal powdered alkali metal iodide free of agglomerates [0068].
Regarding the water content of the lithium iodide ethanol solution following azeotropic distillation in claim 1, it appears that less than 0.5 weight % taught by Guo overlaps the claimed range of 0.01-0.1 weight % such that the range taught by Guo obviates the claimed range. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Guo to use azeotropic distillation to distill ethanol and water, passing the distilled ethanol and water through a drying tube to absorb the distilled water, returning the distilled ethanol to the lithium iodide ethanol solution, until a water content in the lithium iodide ethanol solution is reduced to 0.01-0.1 weight %, in order to produce an ideal powdered alkali metal iodide free of agglomerates, as recognized by Guo [0068].
Wang ‘435 discloses distilling the lithium iodide ethanol solution, wherein pressure is maintained at -0.1 MPa (-0.1 MPa meets the limitation of a negative pressure of 0.085-0.1 MPa) and temperature is raised to 150-300°C and the temperature is maintained for 0.5h-50h (claim 1, step 2.3), and cooling to normal temperature under nitrogen to obtain a white solid of anhydrous lithium iodide (claim 1, step 2.4). Therefore, Wang ‘435 teaches evaporating the ethanol in the lithium iodide ethanol solution for precipitation, introducing a nitrogen protection, maintaining a pressure of -0.1 MPa, and drying at 150-300°C to obtain anhydrous lithium iodide. Further, the method of Wang ‘435 would necessarily comprise a step of closing a vacuum valve on a vessel as Wang ‘435 teaches maintaining a negative pressure followed by cooling under nitrogen (claim 1, steps 2.3-2.4).
Regarding the temperature in the solvent removal step in claim 1, it appears that 150-300°C taught by Wang ‘435 overlaps the claimed range of 135-150°C such that the range taught by Wang ‘435 obviates the claimed range. See MPEP 2144.05 (I).
Wang ‘435 is silent to recovering the ethanol for reuse.
Wang '440 further discloses recycling the organic solvent for reuse so no waste is generated and the environment is not polluted (pg. 3, par. 5). Wang ‘440 further discloses the organic solvent may be ethanol (pg. 2, par. 5).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Wang ‘440 to recover the ethanol for reuse so no waste is generated and the environment is not polluted, as recognized by Wang ‘440 (pg. 3, par. 5).
Wang ‘435 is further silent to obtaining a solid-liquid mixture, separating the solid-liquid mixture using a filter device, and transferring the solid to an oven for additional drying.
However, drying using filtration and a drying oven is a known drying technique, such that it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to obtain a solid-liquid mixture, introducing the solid-liquid mixture into a nitrogen pressure filter device under the nitrogen protection to obtain a solid, and transferring the solid to an oven for additional drying, because adopting such known drying technique to improve a known method of forming desired dried lithium iodide product would have predictable results.
Wang ‘435 further discloses the glove box wherein distillation takes place is filled with high-purity nitrogen (claim 1, step 2.1), such that Wang ‘435 meets the limitation wherein the dry inert gas is nitrogen.
Wang ‘435 is silent to using azeotropic distillation. Wang ‘435 is further silent to the anhydrous lithium iodide having no solid agglomeration.
Guo discloses a method of preparing anhydrous alkali metal iodide (lithium iodide is an alkali metal iodide; [0032]). Guo further discloses alcohols are used as solvents in the reaction process [0051]. Guo further discloses azeotropic distillation for removing water from alcohol, and the alcohol can be added back into the solution to achieve the dehydration effect of the alkali metal iodide [0071]. Guo further discloses alcohol is dehydrated using a desiccant (dehydrating alcohol using a desiccant meets the limitation of passing the distilled ethanol and water through a drying tube to absorb the distilled water; [0072]. Guo further discloses a zeolite can be used as desiccants that physically absorb moisture, and the most typical zeolite is molecular sieve [0069], such that the desiccant of Guo meets the limitation of a drying tube (see claim 6 of the present application). Guo further discloses a water content in the alcohol solution of alkali metal iodide during the dehydration process to be less than 0.5 weight % [0068]. Guo further discloses the dehydration process results in an ideal powdered alkali metal iodide free of agglomerates [0068].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Guo to use azeotropic distillation and for the anhydrous lithium iodide to have no solid agglomeration, as azeotropic distillation results in a product with a lower water content, and therefore, produces an ideal powdered alkali metal iodide free of agglomerates, as recognized by Guo [0068].
Wang ‘435 and Guo are silent to using the protection of a reducing gas during distillation.
Riedel discloses removing water by distillation under the protection of hydrogen (pg. 8, par. 7).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Riedel to use the protection of a reducing gas during distillation, wherein the reducing gas is hydrogen, because performing distillation under the protection of hydrogen is a process parameter well-known in the art of distillation, as recognized by Riedel.
Wang ‘435 further discloses filtering to remove impurities (claim 1, step 2.2) and obtaining a white solid of anhydrous lithium iodide (claim 1, step 2.4), such that Wang ‘435 meets the broad limitation wherein the anhydrous lithium iodide has less impurity content.
Regarding Claim 2, Wang ‘435 is silent to obtaining a lithium iodide trihydrate as well as a mass ratio of lithium iodide trihydrate in ethanol.
Wang ‘440 discloses a method of preparing an anhydrous lithium iodide, comprising: mixing lithium hydroxide monohydrate and hydroiodic acid and evaporating to obtain solid lithium iodide trihydrate, mixing the lithium iodide trihydrate with an organic solvent in a mass ratio of 1:5 to 1:1 (pg. 2, par. 2), wherein the organic solvent may be ethanol (pg. 2, par. 5).
Regarding the mass ratio of lithium iodide trihydrate to ethanol in claim 2, it appears that 1:5 to 1:1 taught by Wang ‘440 overlaps the claimed value of 1:2.5 such that the range taught by Wang ‘440 obviates the claimed range. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Wang ‘440 to provide a step for obtaining lithium iodide trihydrate, wherein in the lithium iodide dissolving step, the mass ratio of the lithium iodide trihydrate to the absolute ethanol in a 1 : 2.5, because obtaining lithium iodide trihydrate and dissolving in ethanol at a mass ratio of 1:2.5 are process parameters well-known in the art of preparing an anhydrous lithium iodide, as recognized by Wang ‘440.
Regarding Claim 3, Wang ‘435 discloses adding hydroiodic acid to the lithium iodide organic solvent solution, which necessarily would adjust a pH of the solution (claim 1, step 2.1). Wang ‘435 also teaches adjusting pH with lithium hydroxide or hydroiodic acid (claim 1, step 1.2), and because the two methods were art recognized equivalents at the time the invention was made, one of ordinary skill in the art would have found it obvious to substitute the hydroiodic acid for the lithium hydroxide. Wang ‘435 further discloses filtering the solution obtained in step 2.1 to remove impurities (claim 1, step 2.2).
Wang ‘435 does not teach adjusting the pH of the lithium iodide ethanol solution to 7-13, or a second step for adjusting pH of the lithium iodide ethanol solution after filtration.
Wang ‘435, however, teaches two pH adjustment steps by adding lithium hydroxide or hydriodic acid (claim 1, step 1.2 and 2.1).
Guo discloses it is recommended to adjust the pH value of the obtained alkali metal iodide with an alkali metal hydroxide to 3-10 for quality stability and product safety [0126].
Regarding the pH adjustment values before and after filtration in claim 3, it appears that 3-10 taught by Guo overlaps the claimed ranges of 7-13 before filtration and 6.0-8.0 after filtration such that the range taught by Guo obviates the claimed range. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Guo to adjust the pH of the lithium iodide ethanol solution to 7-13 before filtration and provide an additional pH adjustment step after filtration with redistilled colorless hydriodic acid to 6.0 to 8.0 as Wang ‘435 teaches two pH adjustment steps using both lithium hydroxide and hydroiodic acid (claim 1, step 1.2 and 2.1), and it is recommended to adjust the pH value of the obtained alkali metal iodide with an alkali metal hydroxide for quality stability and product safety, as recognized by Guo [0126].
Wang ‘435 is silent to filtering via membrane filtration.
Wang ‘435, however, teaches filtering to remove impurities (claim 1, step 2.2).
Miki discloses removing solid impurities from an aqueous solution containing an alkali metal halide (lithium iodide is an alkali metal halide) by filtration under reduced pressure using a membrane filter [0026].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Miki to remove impurities through a membrane filtration device equipped with a membrane element because filtering with a membrane device is a process parameter well-known in the art of removing impurities from a solution containing alkali metal halides, as recognized by Miki.
Miki is silent to the use of a nanofiltration device, and the pore size of the membrane element.
Garikipati discloses using nanofiltration to remove impurities with a pore size of the membrane being 100-2000 Daltons (aka D).
Regarding the pore size of the membrane element in claim 3, it appears that 100-2000 D taught by Garikipati overlaps the claimed range of 100-500D such that the range taught by Garikipati obviates the claimed range. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Miki and Garikipati to remove impurities through a nanofiltration device, and a pore size of the membrane element is 100D - 500D, because performing nanofiltration with a pore size of the membrane element of 100D - 500D is a process parameter well-known in the art of membrane filtration, as recognized by Garikipati.
Regarding Claim 4, Wang ‘435 discloses adding hydroiodic acid to the lithium iodide organic solvent solution, which necessarily would adjust a pH of the solution (claim 1, step 2.1). Wang ‘435 also teaches adjusting pH with lithium hydroxide or hydroiodic acid (claim 1, step 1.2), and because the two methods were art recognized equivalents at the time the invention was made, one of ordinary skill in the art would have found it obvious to substitute the hydroiodic acid for the lithium hydroxide. Wang ‘435 further discloses filtering the solution obtained in step 2.1 to remove impurities (claim 1, step 2.2).
Wang ‘435 does not teach adjusting the pH of the lithium iodide ethanol solution to 10, or a second step for adjusting pH of the lithium iodide ethanol solution after filtration.
Wang ‘435, however, teaches two pH adjustment steps by adding lithium hydroxide or hydriodic acid (claim 1, step 1.2 and 2.1).
Guo discloses it is recommended to adjust the pH value of the obtained alkali metal iodide with an alkali metal hydroxide to 3-10 for quality stability and product safety [0126].
Regarding the pH adjustment values before and after filtration in claim 4, it appears that 3-10 taught by Guo overlaps the claimed value of 10 before filtration and 7.0 after filtration such that the range taught by Guo obviates the claimed range. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Guo to adjust the pH of the lithium iodide ethanol solution to 10 before filtration and provide an additional pH adjustment step after filtration with redistilled colorless hydriodic acid to 7.0 as Wang ‘435 teaches two pH adjustment steps using both lithium hydroxide and hydroiodic acid (claim 1, step 1.2 and 2.1), and it is recommended to adjust the pH value of the obtained alkali metal iodide with an alkali metal hydroxide for quality stability and product safety, as recognized by Guo [0126].
Wang ‘435 is silent to filtering via membrane filtration.
Wang ‘435, however, teaches filtering to remove impurities (claim 1, step 2.2).
Miki discloses removing solid impurities from an aqueous solution containing an alkali metal halide (lithium iodide is an alkali metal halide) by filtration under reduced pressure using a membrane filter [0026].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Miki to remove impurities through a membrane filtration device equipped with a membrane element because filtering with a membrane device is a process parameter well-known in the art of removing impurities from a solution containing alkali metal halides, as recognized by Miki.
Miki is silent to the pressure the membrane filter is under, the use of a nanofiltration device, and the pore size of the membrane element.
Garikipati discloses using nanofiltration to remove impurities with a pore size of the membrane being 100-2000 Daltons (aka D) and operated at a pressure of 70-700 psi [0071], which is equivalent to 0.5-4.8 MPa.
Regarding the filter pressure in claim 4, it appears that 0.5-4.8 MPa taught by Garikipati overlaps the claimed range of 0.4-1.0 MPa such that the range taught by Garikipati obviates the claimed range. See MPEP 2144.05 (I).
Regarding the pore size of the membrane element in claim 4, it appears that 100-2000 D taught by Garikipati overlaps the claimed range of 150-250D such that the range taught by Garikipati obviates the claimed range. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Miki and Garikipati to remove impurities through a membrane filtration device equipped with a membrane element under a pressure of 0.4-1.0 MPa, the membrane filtration device is a nanofiltration device, and a pore size of the membrane element is 150D - 250D, because performing nanofiltration at a pressure of 0.4-1.0 MPa with a pore size of the membrane element is 150D - 250D are process parameters well-known in the art of membrane filtration, as recognized by Garikipati.
Regarding Claim 5, Wang ‘435 discloses distillation of the lithium iodide ethanol solution (aka the mother liquor obtained after filtration) under a pressure of -0.1 MPa, raising the temperature to 150-300°C (claim 1, step 2.3) to obtain a solid of anhydrous lithium iodide (claim 1, step 2.4).
Regarding the temperature during distillation in claim 5, it appears that 150-300°C taught by Wang ‘435 overlaps the claimed value of 150°C such that the range taught by Wang ‘435 obviates the claimed range. See MPEP 2144.05 (I).
Wang ‘435 is silent to using azeotropic distillation and passing the distilled ethanol and water through a drying tube to absorb the distilled water, returning the distilled ethanol to the lithium iodide ethanol solution. Wang ‘435 is further silent to a water content in the lithium iodide ethanol solution after distillation.
Guo discloses a method of preparing anhydrous alkali metal iodide (lithium iodide is an alkali metal iodide; [0032]). Guo further discloses alcohols are used as solvents in the reaction process [0051]. Guo further discloses azeotropic distillation for removing water from alcohol, and the alcohol can be added back into the solution to achieve the dehydration effect of the alkali metal iodide [0071]. Guo further discloses alcohol is dehydrated using a desiccant (dehydrating alcohol using a desiccant meets the limitation of passing the distilled ethanol and water through a drying tube to absorb the distilled water; [0072]. Guo further discloses a zeolite can be used as desiccants that physically absorb moisture, and the most typical zeolite is molecular sieve [0069], such that the desiccant of Guo meets the limitation of a drying tube (see claim 6 of the present application). Guo further discloses a water content in the alcohol solution of alkali metal iodide during the dehydration process to be less than 0.5 weight % [0068]. Guo further discloses the dehydration process results in an ideal powdered alkali metal iodide free of agglomerates [0068].
Regarding the water content of the lithium iodide ethanol solution following azeotropic distillation in claim 5, it appears that less than 0.5 weight % taught by Guo overlaps the claimed value of 0.02 weight % such that the range taught by Guo obviates the claimed range. See MPEP 2144.05 (I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to incorporate the teachings of Guo to use azeotropic distillation to distill ethanol and water, passing the distilled ethanol and water through a drying tube to absorb the distilled water, returning the distilled ethanol to the lithium iodide ethanol solution, until a water content in the lithium iodide ethanol solution is reduced to 0.02 weight %, in order to produce an ideal powdered alkali metal iodide free of agglomerates, as recognized by Guo [0068].
Regarding Claim 6, Guo discloses desiccant such as zeolite can be used as desiccants that physically absorb moisture, and the most typical zeolite is molecular sieve [0069].
Regarding Claim 7, Wang ‘435 discloses raising the temperature to 150-300°C for 0.5-50 h at -0.1 MPa (-0.1 MPa meets the limitation of a negative pressure more than 0.09 MPa; claim 1, step 2.3), followed by cooling under nitrogen protection to obtain a white solid of anhydrous lithium iodide (claim 1, step 2.4), such that Wang ‘435 teaches a drying technique substantially similar to the solvent removal step, wherein the negative pressure is maintained at more than 0.09 MPa in the negative pressure oven and drying is at 140°C.
Regarding the drying temperature in claim 7, it appears that 150-300°C taught by Wang ‘435 is close to the claimed value of 140°C such that the range taught by Wang ‘435 obviates the claimed range. See MPEP 2144.05 (I).
Drying using a drying oven is a known drying technique, such that it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Wang ‘435 to provide a solvent removal step wherein the negative pressure is maintained at more than 0.09 MPa in the negative pressure oven and drying is at 140°C, because adopting such known drying technique to improve a known method of forming desired dried lithium iodide product would have predictable results.
Response to Arguments
Applicant's arguments filed 15 October 2025 have been fully considered but they are not persuasive.
Applicant argues none of the references teaches or suggests “keeping the lithium iodide ethanol solution under the protection of a dry inert gas or reducing gas and a negative pressure of 0.08-0.09 MPa” (“Remarks”, pg. 8, par. 3).
However, Wang ‘435 teaches distillation of the lithium iodide ethanol solution under the protection of a dry inert gas, as distillation is conducted in a glove box, which is filled with nitrogen (claim 1, step 2.1 and 2.3) and a reduced pressure of -0.1 MPa (claim 1, step 2.3), which is close to and, therefore, obviates the claimed pressure range. Guo is relied upon to teach the distillation of the lithium iodide ethanol solution is azeotropic distillation [0071] in order to produce an ideal powdered alkali metal iodide free of agglomerates [0068]. Therefore, the combined prior art teaches azeotropic distillation of the lithium iodide ethanol solution under the protection of a dry inert gas or reducing gas and a negative pressure of 0.08-0.09 MPa.
Applicant argues Miki discloses that the filtration is conducted under reduced pressure, but does not teach or suggest that the azeotropic distillation step is conducted under reduced pressure ("Remarks", pg. 8, par. 4).
However, Miki is relied upon for teaching filtering via membrane filtration for the membrane filtration step, not the azeotropic distillation step. Wang ‘435 teaches distillation of the lithium iodide ethanol solution under a reduced pressure of -0.1 MPa (claim 1, step 2.3), which is close to and, therefore, obviates the claimed pressure range. Guo is relied upon to teach the distillation of the lithium iodide ethanol solution is azeotropic distillation [0071] in order to produce an ideal powdered alkali metal iodide free of agglomerates [0068]. Therefore, the combined prior art teaches azeotropic distillation of the lithium iodide ethanol solution under a negative pressure of 0.08-0.09 MPa.
Applicant argues Riedel only discloses "with exclusion of air and moisture under argon," while claim 1 requires "keeping the lithium iodide ethanol solution under ... a negative pressure of 0.08-0.09 MPa" (“Remarks”, pg. 8, par. 7).
However, Riedel is relied upon for teaching distillation under the protection of hydrogen, not azeotropic distillation. Wang ‘435 teaches distillation of the lithium iodide ethanol solution under a reduced pressure of -0.1 MPa (claim 1, step 2.3), which is close to and, therefore, obviates the claimed pressure range. Guo is relied upon to teach the distillation of the lithium iodide ethanol solution is azeotropic distillation [0071] in order to produce an ideal powdered alkali metal iodide free of agglomerates [0068]. Therefore, the combined prior art teaches azeotropic distillation of the lithium iodide ethanol solution under a negative pressure of 0.08-0.09 MPa.
Applicant argues Riedel discloses the general procedure of handling organometallic compounds, for example, zirconium and hafnium compounds. Riedel does not teach or suggest removing water from lithium iodide (not an organometallic compound) (“Remarks”, pg. 9, par. 1).
However, Riedel is relied upon for teaching distillation under the protection of hydrogen, not removing water from lithium iodide. Guo is relied upon to teach azeotropic distillation for removing water from the lithium iodide ethanol solution [0071].
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).
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.
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/S.E.S./Examiner, Art Unit 1735
/PAUL A WARTALOWICZ/Primary Examiner, Art Unit 1735
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