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 the Claims
Claims 1-3, 5-7, 11, 13-16, 21, and 40-42 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 40-42 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 Claims 16 and 21 have been withdrawn from consideration as a result of the Election/Restriction requirement filed 05/09/2025 as being drawn to a nonelected species or invention.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, 5-7, 11, 13-15, and 40-42 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) (“Brazdil”).
Regarding claims 1, 5-6, and 42, 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, a crystallizer, or a mixture thereof; the teachings of Brazdil 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).
Therefore, regarding claims 1, 5-6, and 42, 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 for an ammonium concentration process as part of an acrylonitrile production process in view of Brazdil. 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. 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 this harsh wet oxidation step in Bradzil’s method, leading one of ordinary skill to the instant invention.
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 claim 11, Mc Clain discloses polymer and acetonitrile foulants (col. 3, lines 1-12).
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”); as applied to claims 1-3, 5-7, 11, 13-15, and 40-42; further in view of Eastman et al. (US 6,294,078 B1 – previously cited).
The teachings of Mc Clain and Bradzil are disclosed above and incorporated herein.
While Mc Clain and Bradzil do not teach the introduction of the antifoulant agent intermittently or continuously, 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 (i.e. 1-10 days) (col. 3, lines 60-66).
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 continuously into a process as taught by Mc Clain and Bradzil 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 and Bradzil’s disclose a method of inhibiting fouling agent formation in evaporators of an ammonium 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 the antifoulant may be applied continuously until the inner surfaces of the reactor are judged to be passivated, or inactive in catalyzing foulant formation (col. 4, lines 1-3). 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.
Claim Rejections - 35 USC § 112(a)
Applicant’s arguments, see page 6, filed 02/03/2026, with respect to 35 USC § 112(a) rejections have been fully considered and are persuasive. The 35 USC § 112(a) rejection of the claims has been withdrawn.
Claim Rejections - 35 USC § 103
Applicant’s arguments, see pages 6-9, filed 02/03/2026, with respect to the 35 USC § 103 rejection of the claims in view of Mc Clain have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Mc Clain and Bradzil, as outlined above.
Applicant refers to Mc Clain as D1 and Eastman as D2 – this convention will be applied here also. Applicant appears to have misinterpreted the Office’s rejection when they state “the Office Action cites D2 as a reference teaching that acrylonitrile production process may comprise an ammonium concentration process” – this is not the case (see final rejection filed 11/21/2025 – pages 7-8). Eastman (D2) is only relied upon to reject claim 7, with respect to frequency of anti-foulant administration.
Applicant argues that D1’s process comprises 3 stages, failing to teach or suggest any additional processing of neutralized ammonia steam or technical problems associated with neutralization, and asserts that one skilled in the art would not look to D1 for guidance. Applicant states one of ordinary skill would have been aware that the combination of chemical engineering processes is not simply connection of different stages, but involves commissioning of different equipment and operating conditions. Applicant states one of ordinary skill would not refer to D1 and expect the sulfonated compound in D1 to also result in acceptable performance in the process equipment of the present application. Applicant states that, like D1, D2 is silent to the problem related to the foulant, and that there is no teaching or suggestion for introducing Mc Clain’s antifoulants into the evaporation/concentration process.
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 (D1) 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, a crystallizer, or a mixture thereof; the teachings of Brazdil 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).
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 for an ammonium concentration process as part of an acrylonitrile production process in view of Brazdil. 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. 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 this harsh wet oxidation step in Bradzil’s method, leading one of ordinary skill to the instant invention.
In response to Applicant’s arguments that one of ordinary skill would have been aware that the combination of chemical engineering processes is not simply connection of different stages, but involves commissioning of different equipment and operating conditions; or that one of ordinary skill would not refer to D1 and expect the sulfonated compound in D1 to also result in acceptable performance in the process equipment of the present application . . . Applicant is advised that MPEP (2141.03 (I)) states: "A person of ordinary skill in the art is also a person of ordinary creativity, not an automaton." KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 421, 82 USPQ2d 1385, 1397 (2007). "[I]n many cases a person of ordinary skill will be able to fit the teachings of multiple patents together like pieces of a puzzle." Id. at 420, 82 USPQ2d 1397. Office personnel may also take into account "the inferences and creative steps that a person of ordinary skill in the art would employ." Id. at 418, 82 USPQ2d at 1396. Applicant is reminded that a person of ordinary skill has good reason to pursue known options within his or her technical grasp.
PNG
media_image1.png
842
1380
media_image1.png
Greyscale
Therefore, a person of ordinary skill would have been able to combine the teachings of Mc Clain and Bradzil to arrive at the instant invention. The instant invention is obvious, since Mc Clain teaches the claimed sulfonated antifoulant agents (including naphthalene sulfonate formaldehyde condensates) for their acrylonitrile production process, which ends with an ammonium concentration step; and Bradzil teaches an ammonium concentration process, wherein the formation of polymers (foulants) is reported, requiring an extra oxidation step (in 17) to remove these polymers (foulants) prior to allowing the ammonia stream into the evaporators (in 19) (see diagram above, obtained from abstract of Bradzil. Thus, a person of ordinary skill would have been motivated to introduce Mc Clain’s foulant inhibitors into Bradzil’s ammonia concentration process, circumventing the need for the harsh oxidation step.
Conclusion
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.
Examiner interviews are available via telephone and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Kortney L. Klinkel can be reached at (571) 270-5239. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/JACKSON J HERNANDEZ/Examiner, Art Unit 1627
/SARAH PIHONAK/Primary Examiner, Art Unit 1627