DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1-16 are pending in the instant application.
Priority
This application is a National Phase Application of International Application Serial No. PCT/EP2022/083584, filed November 29, 2022, which claims the benefit of and priority to Germany Patent Application No.10-2021-131-250.7, filed November 29, 2021.
Information Disclosure Statements
Applicants’ Information Disclosure Statement, filed on 05/28/2024, has been considered. Please refer to Applicant’s copy of the PTO-1449 submitted herewith.
Status of the Claims
Claims 1-16 are under examination on the merits.
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 1-16 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 pre-AIA the applicant regards as the invention.
Specifically, claim 1 contains the phrase “a halogen salt or halogen salt mixture having a proportion of impurities of 0.05% by weight or less, especially of 0.01 % by weight or less”, which renders the claims indefinite because it is unclear whether the limitation (i.e., especially of 0.01 % by weight or less) following the phrase “a proportion of impurities of 0.05% by weight or less” is a part of the claimed invention. See MPEP § 2173.05(c-d). In another word, it is not clear which amount of impurity is the claimed amount one: 0.05% by weight or less, or 0.01 % by weight or less?
In addition, the term “a proportion of impurities” is subject to multiple interpretations. It can be interpreted as a portion of impurities (e.g., Fe, As) is 0.05% by weight or less, or a total impurity of the halogen salt or halogen salt mixture is 0.05% by weight or less. In addition, it is not clear the term “weight” should be interpreted as a total weight of the halogen salt or halogen salt mixture including the impurities, or without including the impurity. The metes and bound of claim 1 are not clear. Therefore, claim 1 is indefinite. Claims 2-16 depending on claim 1 are rejected, accordingly.
Claims 3-4, 13, and 16 are also indefinite because the terms “especially” and “preferably” are used in the claims. A broad range or limitation together with a narrow range or limitation that falls within the broad range or limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c-d).
Claims 1-16 are given a broadest and reasonable interpretation based on the specification, wherein the halogen salt or halogen salt mixture having a proportion of impurities of 0.05% by weight or less of the total weight of the halogen salt or halogen salt mixture including the impurities.
Claim Rejections - 35 USC § 102
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 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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1-11, 13, and 15-16 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by U.S. Patent Application Publication No. US2020/0087156 A1 (“the `156 publication”) to Brian C. Kelleher, published on March 19, 2020.
Applicants’ claim 1 is drawn to a process for reducing impurities in a halogen salt or halogen salt mixtures of two, three or more halogen salts, comprising the following steps:
a) providing a container in which the halogen salt or halogen salt mixture is brought into contact with an active metal, b) providing said halogen salt or halogen salt mixture, which is in a liquid form, c) providing an active metal, d) contacting said halogen salt or halogen salt mixture with said active metal in an inert atmosphere at a temperature that is above the melting temperature of said active metal and above the melting temperature of said halogen salt/halogen salt mixture, whereby impurities in said halogen salt or halogen salt mixture react with said active metal, to obtain a halogen salt or halogen salt mixture having a proportion of impurities of 0.05% by weight or less, especially of 0.01 % by weight or less, and e) separating the purified halogen salt or halogen salt mixture, wherein said halogen salt is a halogen salt of an alkali metal, or an alkaline earth metal, or a transition metal, or a metal of group 13 or 14 of the periodic table, said inert atmosphere consists of nitrogen and/or noble gas, and said active metal is selected to be immiscible with the molten halogen salts, have an electromotive force (EMF) that is not larger than that of the metals forming the cations of the halogen salt or salts, have an electromotive force (EMF) that is larger than that of the corrosive impurities of the halogen salt or salts, and have a density different from that of the purified halogen salt.
Claim interpretation: Claim 1 is interpreted as: wherein the halogen salt or halogen salt mixture having a proportion of impurities of 0.05% by weight or less of the total weight of the halogen salt or halogen salt mixture including the impurities. See the 112(b) rejection above.
The `156 publication (claim 17) discloses a method for manufacturing a less corrosive NaCl—MgCl2 salt (i.e., halogen salt mixture of an alkali metal and an alkaline earth metal) from a NaCl—MgCl2 salt containing at least one impurity, the method comprising: mixing the NaCl—MgCl2 salt containing the at least one impurity with Mg metal (i.e., be immiscible with the molten halogen salts, have an electromotive force (EMF) that is not larger than that of the metals forming the cations of the halogen salt or salts, have an electromotive force (EMF) that is larger than that of the corrosive impurities of the halogen salt or salts, and have a density different from that of the purified halogen salt) at a temperature above the melting point of the NaCl—MgCl2 salt and the Mg metal to obtain a salt-Mg mixture containing at least one reacted impurity; and removing at least some of the at least one reacted impurity from the salt-Mg mixture to obtain the less corrosive NaCl—MgCl2 salt, wherein the less corrosive NaCl—MgCl2 salt has less than 50 mg/kg of impurities. The term “less than 50 mg/kg of impurities” has the same meaning of “less than 0.005% of impurities by weight”. The `156 publication (FIG. 2) discloses a method for manufacturing the less corrosive NaCl—MgCl2 salt including step 218 (Cool the purified halogen salt mixture to a temperature below the melting point of the Mg metal), and step 220 (Separate solids from the salt to obtain a reduced corrosion salt). The `156 publication [0029] discloses the addition operation 206 of FIG. 2 is done in an inert environment, such as in an argon or other inert gas atmosphere. In addition, Example 3 of the `156 publication [0063] discloses the purifier was kept inside of a glove box and opened to its atmosphere. One ordinary skilled in the art would have known that a glove box for performing an inorganic metallic chemistry reaction must be filled with inert gas such as N2 or Ar under inert atmosphere. Therefore, the `156 publication anticipates claims 1-6.
In terms of claim 7, wherein said contacting is performed with agitation, Example 5 of the `156 publication [0065] discloses melt and Mg reduction with agitation, followed by filtration.
In terms of claim 8, wherein said halogen salt has a density higher than that of the liquid active metal, the `156 publication (claim 17) discloses the halogen salt is NaCl—MgCl2 salt, and the liquid active metal is Mg, wherein the density of NaCl is 2.16 g/cm3, and the density of MgCl2 is 2.32 g/cm3, and density of Mg is 1.738 g/cm3. Therefore, halogen salt has a density higher than that of the liquid active metal.
In terms of claim 9, wherein the impurity in the halogen salt is a compound that contains oxygen and/or hydrogen in addition to the cation and anion of the halogen salt, the `156 publication [0092] teaches the at least one impurity includes one or more impurities selected from water (H2O), Fe, FeCl3, Cr, CrCl3, Ni, NiCl3, Cu, CuCl3, V, VCl3, Ti, TiCl3, Mn, MnCl2, Mo, MoCl3, Zn, and ZnCl2, wherein water contains oxygen and/or hydrogen. In addition, the `156 publication [0031] teaches the impurity is Mg(OH)2.
In terms of claim 10, wherein said process is a continuous process, the `156 publication [0192] teaches continuous systems are also possible and could be easily designed using the disclosure above to perform the same methods and generate the same salts in a continuous fashion.
In terms of claim 11, wherein said process is a discontinuous process, the `156 publication [0192] teaches the embodiments described above focused on a batch system for treating MgCl2-X salts, which is a discontinuous process.
In terms of claim 13, wherein the halogen salt has a proportion of impurities of 3% by weight or less, especially 2% or less, preferably 1 % or less, before the process according to the disclosure is performed, the `156 publication [0018] teaches various grades of NaCl—MgCl2 salt (e.g., advertised as “99% pure by metals anhydrous”) with varying (often unspecified) levels of impurities (e.g., water and oxides and hydroxides of Na, Mg, as well as other cations such as Ni, Cr, and Fe, and chlorides of cations other than Na and Mg) are commercially available. In addition, TABLE 1 of the `156 publication [0053] lists the impurities of commercial constituent salts as reported by the manufacturer, which read on the limitations of claim 13.
In terms of claim 15, wherein the active metal is magnesium, and the halogen salt is a mixture containing NaCI, MgCl2 and KCI, the `156 publication [0015] teaches salts for which this method may be suitable include any MgCl2 salt that includes one or more of the following LiCl, NaCl, and KCl. For example, embodiments of low corrosivity salts of MgCl2—NaCl, MgCl2—LiCl, MgCl2—KCl, MgCl2—NaCl—LiCl, MgCl2—NaCl—KCl, MgCl2—NaCl—LiCl—KCl, and MgCl2—KCl—LiCl could be made using this method.
In terms of claim 16, wherein the contacting is carried out at a temperature of from 650°C to 750°C, especially at 700°C, the `156 publication [0057-0058] teaches the contacting is carried out at a temperature of from 650°C to 750°C.
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 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 of this title, 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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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 12 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over the `156 publication in view of Zhao et al., Solar Energy Mater and Solar Cells, (2020), v.215, p.110663(1-11), published on June 29, 2020, and Ding et al., Energy Procedia, (2017), v.135, p82-91.
Determination of the scope and content of the prior art (MPEP §2141.01)
The `156 publication (claim 17) discloses a method for manufacturing a less corrosive NaCl—MgCl2 salt (i.e., halogen salt mixture of an alkali metal and an alkaline earth metal) from a NaCl—MgCl2 salt containing at least one impurity, the method comprising: mixing the NaCl—MgCl2 salt containing the at least one impurity with Mg metal (i.e., be immiscible with the molten halogen salts, have an electromotive force (EMF) that is not larger than that of the metals forming the cations of the halogen salt or salts, have an electromotive force (EMF) that is larger than that of the corrosive impurities of the halogen salt or salts, and have a density different from that of the purified halogen salt) at a temperature above the melting point of the NaCl—MgCl2 salt and the Mg metal to obtain a salt-Mg mixture containing at least one reacted impurity; and removing at least some of the at least one reacted impurity from the salt-Mg mixture to obtain the less corrosive NaCl—MgCl2 salt, wherein the less corrosive NaCl—MgCl2 salt has less than 50 mg/kg of impurities. The term “less than 50 mg/kg of impurities” has the same meaning of “less than 0.005% of impurities by weight”. The `156 publication (FIG. 2) discloses a method for manufacturing the less corrosive NaCl—MgCl2 salt including step 218 (Cool the purified halogen salt mixture to a temperature below the melting point of the Mg metal), and step 220 (Separate solids from the salt to obtain a reduced corrosion salt). The `156 publication [0029] discloses the addition operation 206 of FIG. 2 is done in an inert environment, such as in an argon or other inert gas atmosphere. In addition, Example 3 of the `156 publication [0063] discloses the purifier was kept inside of a glove box and opened to its atmosphere. One ordinary skilled in the art would have known that a glove box for performing an inorganic metallic chemistry reaction must be filled with inert gas such as N2 or Ar under inert atmosphere.
Ascertainment of the difference between the prior art and the claims (MPEP §2141.02)
The difference between claim 12 and the method of the `156 publication is that the prior art does not teach the material of the container with which the halogen salt and active metal come into contact is selected from stainless steel, which in particular is free from nickel and/or a ceramic material, and/or a carbon material, and/or alumina-forming steels.
Finding of prima facie obviousness--rational and motivation (MPEP §2142-2413)
However, the difference is further taught and/or suggested by Zhao et al. Zhao et al. (ABSTRACT) discloses a purification method for MgCl2-containing salt, wherein the salt is MgCl2-KCl-NaCl and heating temperature is at least 650 °C. In addition, Zhao et al. (Fig. 1) discloses the purification setup, wherein the material of the container with which the halogen salt and active metal come into contact is stainless steel 316 furnace vessel, which would have rendered claim 12 obvious.
In terms of claim 14 wherein the concentration of impurities is monitored by means of cyclic voltammetric measurements, or the corrosivity of the salt is monitored by means of OCP measurements, Zhao et al. (left column at p.110663-5) discloses the concentration of impurities is monitored by means of cyclic voltammetric measurement, described by [53] Ding et al., “Cyclic voltammetry for monitoring corrosive impurities in molten chlorides for thermal energy storage”, which would have rendered claim 14 obvious.
Conclusions
Claims 1-16 are rejected.
Telephone Inquiry
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Yong L. Chu, whose telephone number is (571)272-5759. The examiner can normally be reached on M-F 8:30am-5:00pm.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Amber R. Orlando can be reached on 571-270-3149. The fax phone number for the organization where this application or proceeding is assigned is (571) 273-8300.
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/YONG L CHU/Primary Examiner, Art Unit 1731
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