DETAILED ACTION
Notice of Pre-AIA or AIA Status
This Office action is based on the 18/685,379 application filed 21 February 2024, which is being examined under the first inventor to file provisions of the AIA .
Claims 1-20 are pending and have been fully considered.
Claim Objections
Claim 19 is objected to under 37 CFR 1.75 as being a substantial duplicate of claim 4. When two claims in an application are duplicates or else are so close in content that they both cover the same thing, despite a slight difference in wording, it is proper after allowing one claim to object to the other as being a substantial duplicate of the allowed claim. See MPEP § 608.01(m).
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 4-6, 8, 12, 17, and 19-20 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 4 and 19 recite the limitation "the proportion" in line 4. There is insufficient antecedent basis for this limitation in the claims.
Claims 5 and 20 recite the limitation "the components" in line 4 of each. There is insufficient antecedent basis for this limitation in the claim.
Claim 6 recites “wherein at least one of the organic solvents is a mixture consisting of at least 95 wt% of an alcohol.” It appears that the mixture being at least 95 wt % alcohol also includes 100 wt% alcohol, in which case it is no longer a mixture. Thus, it is not clear if the organic solvent is a mixture or not.
Claim 8 recites the limitation "the organic solvent" in line 2. There is insufficient antecedent basis for this limitation in the claim. Perhaps, claim 8 should recite “The process according to Claims [[1]] 2 or 4,…”
Claim 12 recites the limitation "the purification" in line 3. There is insufficient antecedent basis for this limitation in the claim. Also, the claim recites “the addition or recycling” in line 4. The limitation should recite “…the adding of the…” Such corresponds to the recitation of instant claim 1 from which 12 depends.
Claim 17 recites the limitation "the reaction solution " in lines 3-4. There is insufficient antecedent basis for this limitation in the claim. Perhaps claim 17 should depend from claim 16 instead.
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 (i.e., changing from AIA to pre-AIA ) 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, 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.
Claim(s) 1, 3-4, 6, 8-13, 15, and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lygin et al (US 2019/0099731) in view of Diao et al in Applied Catalysis B: Environmental (2013, vol 142-143, pp 329-336).
With respect to claims 1 and 9, Lygin et al discloses a “process…of a heterogeneously catalysed oxidation reaction with an oxygen-containing gas…Some examples of the appropriate oxidation processes in the liquid phase are, for example, specific oxidations of alkenes, alkylaromatics, oxidative esterification of aldehydes to carboxylic esters, for example the conversion of (meth)acrolein to alkyl (meth)acrylate, and further selective oxidation reactions in the specialties sector. Most preferably, the heterogeneously catalysed reaction is a continuous oxidative esterification of methacrolein with oxygen and methanol for preparation of methyl methacrylate” [paragraphs 0060-0062]. More specifically, Lygin et al teaches “[t]he pH of a 42.5% by weight solution of methacrolein (MAL) in methanol was adjusted to pH=7 with stirring by the addition of a 1% by weight solution of NaOH in methanol. This solution was fed at a constant feed rate continuously into the upper portion of the draft tube (zone 1) of the reactor usable in accordance with the invention according to FIG. 1 at pressure 5 bara and internal temperature 80° C. At the same time, a sufficient amount of 1% by weight NaOH solution in methanol, together with 600 g of Au/NiO/SiO2—Al2O3—MgO powder catalyst…was fed into this reactor (including in the upper portion of the draft tube) that the value pH=7 in the reactor remained constant. In the lower portion of the reactor, in zone 2, air was metered in via multiple gas distributors. The product mixture was separated from the majority of the heterogeneous catalyst by means of a continuously backwashable sedimentation system (inclined clarifier) present at the periphery of the upper portion of zone 2 and filtered through a filtration system” [paragraph 0076]. Additionally, Lygin et al teaches “[a]lternatively or additionally, and as it were preferably, the reaction mixture is discharged continuously from the reactor and filtered through at least one external filter. Thereafter, the catalyst is optionally subjected to further treatment after the filtration and passed partly or completely back into the reactor. This further treatment may, for example, involve washing, reactivating or separation by particle size. Upstream of such filters, it is preferably possible to install an additional sedimentation system, for example at the periphery of the reactor as well. This may be a specific zone with laminar flow, where a majority of the catalyst used is sedimented. Such sedimentation is thus effected before the actual filtration. One possible variant of such a sedimentation system is, for example, an assembly composed of inclined elements, for example tubes, or inclined metal sheets (for example an inclined clarifier).” [paragraphs 0049-0051]. Note that while a Au/NiO/SiO2—Al2O3—MgO powder catalyst was discussed above, the reference further discloses “[t]he heterogeneous catalysts used are preferably noble metal-containing, especially Pt-, Pd-, Ru-, Rh-, Ru-, Au- and/or Ag-containing, supported catalysts. The supports used may especially be mineral oxides, oxide mixtures, activated carbon, polymer materials or other substances” [paragraph 0063].
Lygin et al does not explicitly disclose step d. of instant claim 1. However, as noted above, the reference teaches the “catalyst is optionally subjected to further treatment after the filtration and passed partly or completely back into the reactor. This further treatment may…involve…reactivating.”
Diao et al, which is concerned with “deactivation of the supported bimetallic Pd–Pb catalyst in the repeated runs of direct oxidative esterification of methacrolein with methanol in the atmosphere” [abstract] to form methyl methacrylate, discloses “[t]he deactivated catalyst can be regenerated in many methods. The adsorbed substances in the catalyst could be desorbed by washing the deactivated catalyst, which would result in the reactivation of the deactivated catalyst. The deactivated catalyst…was washed by stirring in either MeOH or an aqueous hydrazine solution at the reaction temperature of 80◦C for 10 h. A new direct oxidative esterification of MAL with MeOH over the regenerated catalyst in the atmosphere was then carried out in batch process (shown in Fig. 8). The results in Fig. 8 indicated that washing the deactivated catalyst with either MeOH or an aqueous hydrazine solution could completely recover its activity, signifying that washing was effective in extracting the substances adsorbed on the catalyst” [see 1st paragraph under the heading “3.3. Reactivating the degraded catalyst” on page 334].
At the time of the effective filing date of the instant application, it would have been obvious to one of ordinary skill in the art to use the regeneration (reactivating) process of Diao et al that includes heating to 80o C and washing/treating the catalyst with aqueous hydrazine, a basic solution, because the process produces a regenerated/reactivated catalyst that has a higher activity and selectivity than fresh catalyst [see, again, 1st paragraph: “The activity and selectivity of the regenerated catalyst were a little higher than that of the fresh catalyst…”]. Therefore, the invention as a whole would have been prima facie obvious.
With respect to claim 3, Lygin et al discloses “[s]lurry reactors are employed particularly for heterogeneously catalysed processes for which good mixing and low temperature and concentration gradients are advantageous” [paragraph 0004]. If catalyst is removed from a reactor in which an exothermic reaction occurs, it would be obvious to one of ordinary skill in the art to modify the reaction conditions to maintain low temperature gradients by increasing the reaction temperature.
With respect to claims 4 and 19, the aqueous hydrazine corresponds to the organic solvent and water. Additionally, it would have been obvious to reduce the concentration of methacrolein to the greatest extent possible to improve activity and selectivity of the regenerated catalyst.
With respect to claim 6, note the teaching of washing with methanol above, which may obviously be 100 wt % methanol.
With respect to claim 8, if methanol is used to treat/wash the deactivated catalyst, since it is also a reactant in the oxidative esterification reaction, it would have been obvious to use said methanol in the reaction.
With respect to claims 10 and 11, note that the selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297. Consequently, it would be obvious to substitute the catalyst of Diao et al for the catalyst of Lygin et al. Additionally, note that Diao et al discloses “[t]he Pd5Pb5/MgO–Al2O3 catalyst was prepared by the incipient impregnation of MgO–Al2O3 with a mixed aqueous solution of palladium chloride and lead acetate at 50–100◦C under stirring for 1 h” [see paragraph under the heading “2.1.2. Synthesis of the Pd5Pb5/MgO–Al2O3 catalyst” on page 330]. Also note the average pore diameters in Table 3, particularly 8 nm. Since the catalyst of Diao et al is prepared by incipient wetness impregnation, wherein a metal precursor is dissolved in a solvent, and the exact volume of this solution is matched to the pore volume of the support material so capillary action draws the liquid inward, it is obvious that the diameter of the Pd is within the recited range of claim 10.
With respect to claim 12, Lygin et al discloses “[t]he catalyst used can be withdrawn from the reactor continuously or batchwise, for example for a washing and/or regenerating operation, for continuous monitoring/analysis or renewal” [paragraph 0064]. Note that batchwise corresponds to semi-continuously. Additionally, if the withdrawal is batchwise, it is obvious that the separation from the product mixture may also be batchwise as well as the regeneration of the catalyst via heating to 80o C and mixing with aqueous hydrazine. Additionally, if regeneration is performed batchwise, adding regenerated catalyst to the reactor would also, obviously, be performed batchwise (or semi-continuously).
With respect to claim 13, Lygin et al discloses “a catalyst used with preference for such an oxidation reaction has a mean diameter between 10 and 200 μm” [paragraph 0063]. Also, recall, the reference teaches “The product mixture was separated from the majority of the heterogeneous catalyst by means of a continuously backwashable sedimentation system (inclined clarifier),” which clarifier corresponds to the recited settler.
With respect to claim 15, Lygin et al discloses “[f]or additional retention of the fine catalyst particles, the reaction mixture, once it has been filtered through reactor filters (5), is preferably filtered at least once more through finer filters having porosity of 1 to 10 μm outside the reactor, such that the particles of not more than 5 μm are retained by the filter to an extent of at least 90%” [paragraph 0054]. Thus, said fines are not recycled but retained by the filter.
Allowable Subject Matter
Claims 5 and 20 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.
Claims 2, 7, 14, and 16-18 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including 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: with respect to claim 2, the prior art does not teach “an aqueous hydroxide solution is used as the basic solution, and/or the thermal treatment takes place at temperatures between 250 and 750°C;” recall that the temperature taught by Lygin et al is 80o C and treating with aqueous hydrazine. With respect to claims 5 and 20, the prior art does not teach any of the recited organic solvents; with respect to claim 7, the prior art does not teach “the basic solution is a hydroxide solution…;” with respect to claim 14, while the reactor of Lygin et al is a three-phase reactor [see, e.g., abstract & claim 1], which may include fixed-bed reactors, the reference suggests that the catalyst is a slurry rather than fixed-bed [see e. and f. in table under paragraph 0069: e: Catalyst slurry outlet…f: Catalyst slurry inlet]. With respect to claim 16, Lygin et al does not disclose a reaction solution containing between 2 and 10 wt % water; with respect to claim 17, the reference teaches reaction zones 1 and 2 having different catalyst concentrations; there is no teaching of a circulation stream containing a lower concentration of catalyst than the reactor or any zone within the reactor. With respect to claim 18, the prior art fails to teach “the at least one precious metal is obtained in elemental metal form and is optionally used for producing fresh catalyst.”
Conclusion
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/BRIAN A MCCAIG/Primary Examiner, Art Unit 1772
25 July 2026
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