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 .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 05/04/2026 was filed after the mailing date of the non-final rejection on 03/11/2026. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Status of the Claims
Claims 1-3, 5-7, 11, 13-16, 21, and 40-45 are pending in this application. Claims 4, 8-10, 12, 17-20, and 22-39 have been cancelled by applicant. Claims 1-3, 5-7, 11, 13-15, and 40-45 are under examination herein. Claims 16 and 21 have been withdrawn from consideration as a result of the Election/Restriction requirement filed 05/09/2025 as being drawn to a nonelected species or invention.
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.
Claims 1-3, 5-6, 11, 13-15, and 40-45 are rejected under 35 U.S.C. 103 as being unpatentable over Mc Clain et al. (US 5,650,072 – From IDS – previously cited); in view of Brazdil, Jr. et al. (US 5,895,635 – previously cited) (“Brazdil”); and Tinge (WO 2014/206869) (“Tinge”).
Regarding claims 1, 5-6, and 42-44, Mc Clain teaches a method of inhibiting fouling in a process comprising addition of sulfonated oils, sulfonated fatty acids etc. (reading on claims 1, 40, and 42) (abstract). Mc Clain discloses the manufacture of acrylonitrile from the gas phase ammoxidation of propylene (reading on claims 5-6) (col. 2, lines 53-55) and further teaches a stream of acid, such as sulfuric acid, is passed countercurrent to the process of acrylonitrile preparation in order to neutralize and recover any ammonia present (reading on ammonium concentration) (col. 2, lines 55-58).
While McClain does not specifically teach their process equipment for ammonium concentration comprising an evaporator and a crystallizer; the teachings of Brazdil and Tinge are relied upon for these disclosures.
Brazdil teaches a process for the recovery of unreacted ammonia from the reactor effluent obtained from a reaction zone used to produce acrylonitrile (abstract). Bradzil teaches a preferred embodiment of their invention in which an ammonia stream is transferred to an evaporator for water removal (col. 3, lines 16-21). Brazdil teaches passing their quench bottom stream through a wet oxidation reactor to remove polymers formed during the ammoxidation process (reading on foulants) (col. 4, lines 40-57; col. 5, lines 18-22). Bradzil teaches ammonia is released during wet oxidation step and has to be recycled into fluid bed (col. 5, lines 30-35). Bradzil discloses wet oxidation conditions to remove unwanted polymers (foulants) comprise pressures between 600-3000 psi and temperatures between 200-650 °C (col. 5, lines 35-45).
Tinge teaches a process and apparatus for producing ammonium sulfate crystals (abstract). Tinge discloses most industrial acrylonitrile is produced by ammoxidation of propene, and ammonia is separated from the product stream using sulfuric acid, resulting in ammonium sulfate (para. bridging pages 1-2). Tinge teaches ammonium sulfate may be obtained by subjecting an ammonium sulfate solution to crystallization by evaporating the solvent (usually water) in a series of crystallizers; Tinge also discloses that adding an evaporator reduces energy consumption (page 2).
Therefore, regarding claims 1, 5-6, and 42-44, it would have been prima facie obvious to one of ordinary skill prior to the effective filing date of the claimed invention to introduce Mc Clain’s sulfonated oil antifouling agents into the evaporators and crystallizers for an ammonium sulfate concentration process as part of an acrylonitrile production process in view of Brazdil and Tinge. One of ordinary skill would have been motivated to do so with a reasonable expectation of success because Mc Clain teaches a method of inhibiting foulant deposition by introducing sulfonated oils into an ammoxidation of propylene process which comprises ammonium concentration and recovery at the end of their stream; further because Bradzil teaches an ammonium concentration process comprising evaporators to remove water from their ammonia stream, and discloses their method comprises passing a quench stream through a harsh wet oxidation (600-3000 psi and temperatures between 200-650 °C) to remove foulants, during which some ammonia is lost and has to be recycled; and further because Tinge discloses industrial acrylonitrile is produced by ammoxidation of propene, and ammonia is separated from the product stream using sulfuric acid, resulting in ammonium sulfate, which can be concentrated and recovered with their process and apparatus comprising evaporators and crystallizers. Thus, Mc Clain’s disclosure of the introduction of sulfonated oil anti-foulants to inhibit deposition of polymers (foulants) in the process, would circumvent the need for the harsh wet oxidation step in Bradzil’s method, leading one of ordinary skill to the instant invention; and Tinge’s methods and apparatus comprising evaporators and crystallizers would allow for efficient recovery of the ammonium sulfate resulting from the ammoxidation of propene.
Regarding claims 2-3, Applicant is advised that In re Best (195 USPQ 430) and In re Fitzgerald (205 USPQ 594) discuss the support of rejections wherein the prior art discloses subject matter which there is reason to believe includes functions that are newly cited or is identical to a product instantly claimed. In such a situation the burden is shifted to the applicants to “prove that subject matter shown to be in the prior art does not possess the characteristic relied on.” MPEP 2112 (V).
Further regarding claim 2, Mc Clain discloses injection of an antioxidant into a process to help control formation of a polymer foulant, however, some polymer is still formed. Mc Clain suggests that addition of a dispersant would help move this polymer from the exchanger surface, thus improving unit operation. Mc Clain’s disclosure suggests that one may inject the antifoulant into the process equipment, just as one may inject the antioxidant to prevent formation of the foulant (col. 2, lines 46-52).
Further regarding claim 3, Mc Clain discloses acrylonitrile is prepared and separated from any acetonitriles present by distillation, leaving behind about 1% organic material and polymers like polyacrylic acid and its salts, which may foul the surfaces of heat exchangers and inhibit production. Mc Clain discloses that addition of an antifoulant in the process would help alleviate the problem (col. 3, lines 1-12), reading on introduction of antifoulant during the process.
Regarding claims 11 and 45, Tinge discloses most industrial acrylonitrile is produced by ammoxidation of propene, and ammonia is separated from the product stream using sulfuric acid, resulting in ammonium sulfate (para. bridging pages 1-2). Tinge discloses 0.2 tons of ammonium sulfate are produced per ton of produced acrylonitrile, thus one of ordinary skill would expect ammonium sulfate to be present in the foulant of the ammonium concentration process.
Regarding claim 13, Mc Clain teaches a method of inhibiting fouling in a process comprising addition of 0.1-10,000 ppm of antifouling agent (abstract).
Applicant is advised that the courts have stated where the claimed ranges overlap or lie inside the ranges disclosed by the prior art and even when the claimed ranges and prior art ranges do not overlap but are close enough that one skilled in the art would have expected them to have similar properties, a prima facie case of obviousness exists. See In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); Titanium Metals Corp. of America v. Banner, 778 F2d 775. 227 USPQ 773 (Fed. Cir. 1985) (see MPEP 2144.05.01). The courts have also found 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. See In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). See MPEP 2144.05-II.
Therefore, the claimed ranges merely represent an obvious variant and/or routine optimization of the values of the cited prior art.
Regarding claim 14, Mc Clain discloses injection of an antioxidant to inhibit or control polymer formation (reading on polymer inhibitors) (col. 2, lines 46-52).
Regarding claim 15, Mc Clain discloses naphthalene sulfonate formaldehyde (col. 3, lines 31-32).
Regarding claim 40-41, Mc Clain discloses naphthalene sulfonate formaldehydes may be neutralized with a variety of bases, including sodium, potassium, calcium, and ammonium hydroxides (reading on naphthalene sulfonic acid copolymer or alkali or alkali metal salt thereof) (col. 3, lines 30-42).
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Mc Clain et al. (US 5,650,072 – From IDS – previously cited); in view of Brazdil, Jr. et al. (US 5,895,635) (“Brazdil”); and Tinge (WO 2014/206869) (“Tinge”); as applied to claims 1-3, 5-6, 11, 13-15, and 40-45; further in view of Eastman et al. (US 6,294,078 B1 – previously cited) (“Eastman”).
The teachings of Mc Clain, Bradzil, and Tinge are disclosed above and incorporated herein.
While Mc Clain in view of Bradzil and Tinge do not teach the introduction of the antifoulant agent intermittently, the teachings of Eastman are relied upon for these disclosures.
Eastman discloses automatic control of antifoulant concentration is implemented, and can be continued for a predetermined amount of time (col. 3, lines 60-66; claims 1 and 6). Eastman discloses antifoulant flow can be stopped when inner surfaces of the reactor are judged to be passivated (col. 4). Thus, Eastman suggests antifoulant can be introduced intermittently when foulant is detected, and stopped when surfaces of reactor are deemed as passivated, the reintroduced when surfaces become fouled again.
Therefore, it would have been prima facie obvious to one of ordinary skill prior to the effective filing date of the instant application to introduce an antifoulant agent intermittently into a process as taught by Mc Clain, Bradzil, and Tinge in view of Eastman. One of ordinary skill would have been motivated to do so with a reasonable expectation of success because Mc Clain’s, Bradzil’s, and Tinge’s disclose a method of inhibiting fouling agent formation in evaporators and crystallizers of an ammonium sulfate concentration process that is part of an ammoxidation of propylene process; further because Mc Clain teaches that materials that foul the surfaces result in decreased production efficiency; and further because Eastman teaches automatic control of antifoulant concentration is implemented, and can be continued for a predetermined amount of time until the inner surfaces of the reactor are judged to be passivated, or inactive in catalyzing foulant formation (col. 4, lines 1-3), then may be stopped and reintroduced as needed based on surface fouling. A person with ordinary skill has good reason to pursue known options within his or her technical grasp. Note: MPEP 2143(E) KSR, 550 U.S. at 421, 82 USPQ2d at 1397.
Response to Arguments
Claims
Claim amendments are acknowledged and have been entered. No new matter has been introduced.
Claim Rejections - 35 USC § 103
Applicant’s arguments, see pages 6-7, filed 06/08/2026, with respect to the 35 USC § 103 rejection of the claims in view of Mc Clain and Bradzil have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration and in view of claim amendments, a new ground(s) of rejection is made in view of Mc Clain in view of Bradzil and Tinge, as outlined above.
Applicant argues that Mc Claim, Bradzil, and Eastman do not teach process equipment comprising evaporators and a crystallizer, and states one of ordinary skill would not have been motivated to select a method with the features of the instant claims.
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 response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007).
In this case, Mc Clain teaches a method of inhibiting fouling in a process comprising addition of sulfonated oils, sulfonated fatty acids etc. (reading on claims 1, 40, and 42) (abstract). Mc Clain discloses the manufacture of acrylonitrile from the gas phase ammoxidation of propylene (reading on claims 5-6) (col. 2, lines 53-55) and further teaches a stream of acid, such as sulfuric acid, is passed countercurrent to the process of acrylonitrile preparation in order to neutralize and recover any ammonia present (reading on ammonium concentration) (col. 2, lines 55-58).
Brazdil teaches a process for the recovery of unreacted ammonia from the reactor effluent obtained from a reaction zone used to produce acrylonitrile (abstract). Bradzil teaches a preferred embodiment of their invention in which an ammonia stream is transferred to an evaporator for water removal (col. 3, lines 16-21). Brazdil teaches passing their quench bottom stream through a wet oxidation reactor to remove polymers formed during the ammoxidation process (reading on foulants) (col. 4, lines 40-57; col. 5, lines 18-22). Bradzil teaches ammonia is released during wet oxidation step and has to be recycled into fluid bed (col. 5, lines 30-35). Bradzil discloses wet oxidation conditions to remove unwanted polymers (foulants) comprise pressures between 600-3000 psi and temperatures between 200-650 °C (col. 5, lines 35-45).
Tinge teaches a process and apparatus for producing ammonium sulfate crystals (abstract). Tinge discloses most industrial acrylonitrile is produced by ammoxidation of propene, and ammonia is separated from the product stream using sulfuric acid, resulting in ammonium sulfate (para. bridging pages 1-2). Tinge teaches ammonium sulfate may be obtained by subjecting an ammonium sulfate solution to crystallization by evaporating the solvent (usually water) in a series of crystallizers; Tinge also discloses that adding an evaporator reduces energy consumption (page 2).
Therefore, it would have been prima facie obvious to one of ordinary skill prior to the effective filing date of the claimed invention to introduce Mc Clain’s sulfonated oil antifouling agents into the evaporators and crystallizers for an ammonium sulfate concentration process as part of an acrylonitrile production process in view of Brazdil and Tinge. One of ordinary skill would have been motivated to do so with a reasonable expectation of success because Mc Clain teaches a method of inhibiting foulant deposition by introducing sulfonated oils into an ammoxidation of propylene process which comprises ammonium concentration and recovery at the end of their stream; further because Bradzil teaches an ammonium concentration process comprising evaporators to remove water from their ammonia stream, and discloses their method comprises passing a quench stream through a harsh wet oxidation (600-3000 psi and temperatures between 200-650 °C) to remove foulants, during which some ammonia is lost and has to be recycled; and further because Tinge discloses industrial acrylonitrile is produced by ammoxidation of propene, and ammonia is separated from the product stream using sulfuric acid, resulting in ammonium sulfate, which can be concentrated and recovered with their process and apparatus comprising evaporators and crystallizers. Thus, Mc Clain’s disclosure of the introduction of sulfonated oil anti-foulants to inhibit deposition of polymers (foulants) in the process, would circumvent the need for the harsh wet oxidation step in Bradzil’s method, leading one of ordinary skill to the instant invention; and Tinge’s methods and apparatus comprising evaporators and crystallizers would allow for efficient recovery of the ammonium sulfate resulting from the ammoxidation of propene.
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 JACKSON J HERNANDEZ whose telephone number is (571)272-5382. The examiner can normally be reached Mon - Thurs 7:30 to 5.
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/JACKSON J HERNANDEZ/Examiner, Art Unit 1627 /SARAH PIHONAK/Primary Examiner, Art Unit 1627
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