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 .
Status of Claims
Claims 1, 2, 7, and 19 are currently amended and Claims 3-6 and 8-18 are as originally filed.
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 13 and 18 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.
Claims 13 and 18 recite a percentage without a basis, e.g. mass, volume, or mole. The lack of a basis makes the limitation unclear. Correction is required, though new matter will be subject to analysis under 35 U.S.C. 112, first paragraph. In this case, it is not clear what units are being used to define the strength of the hypochlorite solution, mass percent (e.g. m/m) or volume percent (e.g. v/v). The specification does not refer to either basis for support.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 19 are rejected under 35 U.S.C. 103 as being unpatentable over GB 2 349 876 A in view of Foley et al (US 2018/0112289 A1), Calla-Choque et al in Revista Mexicana de Ingeniería Química.
GB 2 349 876 A (GB ‘876) teaches recovering noble metals from ores and other materials that contain them (page 1, lines 8-10) using thiourea as represented below in Figure 1:
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The stripped leach liquor is treated with a reducing agent to regenerate thiourea, and the regenerated liquor is recycled to the leaching circuit. Therefore, thiourea is dissolve in liquid form, and the reductant at the thiourea leaching step is sodium metabisulfite (page 6, lines 15-31). The amount of sodium metabisulfite present is not recited in the claims to maintain the required thiourea:formamidine disulphide ratio. This mixture is mixed with acid to maintain the required pH control (page 6, line 22), and the acid is sulfuric (page 5, line 11). Therefore, GB ‘876 teaches step (i). Regarding step (ii), an oxidant is added, for example ferric ion or other suitable oxidation agent (lines 25-27). Regarding step (iii), solid material from the acid pretreatment contains metals is added to the thiourea leaching step as represented in the figure above. The noble metals may be stripped or recovered by ion exchange resin, carbon-in-leach, carbon-in-pulp, cementation, electrowinning, or other methods (page 6, lines 10-13). However, GB ‘876 does not teach the oxidation agent is hypochlorite or titrating thiourea as claimed.
Regarding hypochlorite as an oxidation agent, Foley et al is applied as discussed above. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use hypochlorite as an oxidation agent in GB ‘876, since Foley et al teaches that hydrogen peroxide and hypochlorite are equivalent as oxidation agents for thiourea leaching.
Regarding titrating thiourea, Calla-Choque et al is applied as discussed above. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use the titration technique of Calla-Choque et al to maintain the thiourea concentration in the process of GB ‘876, since Calla-Choque et al teaches permitting precise determination of thiourea concentrations (abstract).
Response to Arguments
Applicant's arguments filed 03/04/2026 have been fully considered but they are not persuasive. Regarding the rejection under 35 U.S.C. 112(b) for Claims 13 and 18, applicant’s response does not address the lack of basis for the concentration. As evidenced by LibreTexts, though percent of a solute in a solution is a way to describe the concentration, there are two different ways of representing this percentage: mass percent or volume percent.
Regarding the rejections under 35 U.S.C. 103(a), the indication for reasons for allowance were based on the subject matter of Claim 7, which recites having total dissolution of thiourea and sodium metabisulfite in aqueous sulfuric acid solution before the addition of a source of hypochlorite.
Allowable Subject Matter
Claims 1-12 and 14-17 are allowed.
Claims 13 and 18 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter: Regarding Claims 1-6, 8-10, and 12-15, the cited prior art does not suggest having total dissolution of thiourea and sodium metabisulfite in aqueous sulfuric acid solution before the addition of a source of hypochlorite.
Conclusion
THIS ACTION IS MADE FINAL. 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 Tima M. McGuthry-Banks whose telephone number is (571)272-2744. The examiner can normally be reached Monday through Friday, 7:30 am to 4:00 pm.
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Tima M. McGuthry-Banks
Primary Examiner
Art Unit 1733
/TIMA M. MCGUTHRY-BANKS/Primary Examiner, Art Unit 1733
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