HALDOR TOPSØE A/S

Patent Trials and Appeals Board

Jan 12, 2022

2021003132 (P.T.A.B. Jan. 12, 2022)

UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 16/096,493 10/25/2018 Poul Erik HØJLUND NIELSEN 0089865-000035 1592 21839 7590 01/12/2022 BUCHANAN, INGERSOLL & ROONEY PC 1737 KING STREET SUITE 500 ALEXANDRIA, VA 22314-2727 EXAMINER KOSACK, JOSEPH R ART UNIT PAPER NUMBER 1626 NOTIFICATION DATE DELIVERY MODE 01/12/2022 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): ADIPDOC1@BIPC.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE __________ BEFORE THE PATENT TRIAL AND APPEAL BOARD __________ Ex parte POUL ERIK HØJLUND NIELSEN, BURCIN TEMEL MCKENNA, JOHN BØGILD HANSEN, and RASMUS MUNKSGÅRD NIELSEN __________ Appeal 2021-003132 Application 16/096,493 Technology Center 1600 __________ Before RICHARD M. LEBOVITZ, JEFFREY N. FREDMAN, and ULRIKE W. JENKS, Administrative Patent Judges. FREDMAN, Administrative Patent Judge. DECISION ON APPEAL This is an appeal1 under 35 U.S.C. § 134 involving claims to a process for the synthesis of a nitrile. The Examiner rejected the claims as obvious. We have jurisdiction under 35 U.S.C. § 6(b). We reverse. 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies the Real Party in Interest as HALDOR TOPSØE A/S (see Appeal Br. 2). We have considered the Specification filed Oct. 25, 2018 (“Spec.”); Final Rejection of Aug. 19, 2020 (“Final Act.”); Appeal Brief filed Dec. 16, 2020 (“Appeal Br.”); Examiner’s Answer filed Mar. 8, 2021 (“Ans.”); and Reply Brief filed Apr. 13, 2021 (“Reply Br.”). An oral hearing was held on Dec. 15, 2021. Appeal 2021-003132 Application 16/096,493 2 Statement of the Case Background “The non-oxidative synthesis of nitriles . . . is a high temperature process which takes place between 700 and 1000°C” (Spec. 1:8-11). “The concept of using inductive heating to heat a catalyst during a gas phase chemical reaction at elevated temperature is generally known in the art” (id. at 2:10-12). “This procedure is, however, not very energy efficient, because the magnetic field generated by the coil will continue also outside the coil” (id. at 4:8-10). “While this drawback may be avoided by shaping the coil as a torus, there will still be a loss due to the resistance in the coil, i.e. the ohmic heat, which normally will be lost for the process” (id. at 4:10-13). The Specification teaches a “more energy efficient approach. . . . the coil will be mounted within the reactor, and the catalyst will be placed inside the coil. This way, the ohmic heat will not be lost for the process, and . . . the magnetic field generated by the coil will not be able to penetrate out of the reactor” (Spec. 4:16-23). The Claims Claims 1, 4, and 6-15 are on appeal. Claim 1 is an independent claim, is representative, and reads as follows: 1. A process for the synthesis of a nitrile by catalyzed reaction of ammonia with a hydrocarbon using heating obtained by passing an alternating current through a metallic coil in a synthesis reactor with a catalyst, wherein the endothermic reaction between ammonia and the hydrocarbon takes place in the synthesis reactor with direct inductive heating in a reaction zone, wherein the coil is mounted within the synthesis reactor, and all of the catalyst is placed inside the coil. Appeal 2021-003132 Application 16/096,493 3 The Rejections A. The Examiner rejected claims 1, 10, and 12-15 under 35 U.S.C. § 103(a) as obvious over Slaten2 and Blackwell3 (Final Act. 6-7). B. The Examiner rejected claims 1, 4, and 6-15 under 35 U.S.C. § 103(a) as anticipated by Slaten, Blackwell, and Hojlund4 (Final Act. 7-9). A. 35 U.S.C. § 103(a) over Slaten and Blackwell The Examiner finds Slaten teaches a process for the synthesis of a nitrile by catalyzed reaction of ammonia with methane using heating obtained by passing AC through a metallic coil wire, wherein the endothermic reaction occurs in a reactor with direct inductive heating in the reaction zone. Slaten also teaches that the catalyst is placed inside of the coil. (Final Act. 6). The Examiner acknowledges that “Slaten does not specifically teach . . . all of the catalyst is placed inside of the coil” (id. at 7). The Examiner finds Blackwell teaches a “catalyzed reaction of ammonia with methane using heating obtained by passing AC through a metallic copper tube, wherein the endothermic reaction occurs in a reactor with direct inductive heating in the reaction zone and all of the catalyst is placed inside of the coil” (id.). The issue with respect to this rejection is: Does a preponderance of the evidence of record support the Examiner’s conclusion that Slaten and Blackwell render the claimed method obvious? 2 Slaten, C., US 8,906,334 B2, issued Dec. 9, 2014. 3 Blackwell et al., EP 1,480,740 B1, published Apr. 29, 2009. 4 Hojlund et al., DK 2015 00118 A1, published Mar. 23, 2015. Appeal 2021-003132 Application 16/096,493 4 Findings of Fact 1. Slaten teaches “a process for synthesizing HCN in a sustained continuous endothermic reaction. The process steps comprise: reacting, using a catalyst, a portion of methane-containing hydrocarbon gas and a portion of ammonia gas at a reaction temperature above about 1000° C” (Slaten 4:5-9). 2. Figure 10 of Slaten is reproduced below: “FIG. 10 is a representation of an apparatus in accordance with the present invention” (Slaten 6:29-30). 3. Slaten teaches a high temperature heat pipe 401 comprised of an envelope formed from an appropriate high temperature metallurgy such as Inconel 600, with an internal vapor space containing a high temperature working fluid . . . The heat pipe 401 is coated with Appeal 2021-003132 Application 16/096,493 5 platinum using an electroplating technique. An energy source and reaction vessel is prepared by placing an induction coil 402 into an appropriately sized vessel 403 then forming a ceramic lining 404 . . . The casting is formed such that the heat pipe 401, placed entirely within the reactor vessel, is supported by the castable ceramic lining and is axially aligned with reactor vessel and induction coil 402 such that the induction coil 402 surrounds a portion of one end of the heat pipe 401. An annular gap is provided between the castable ceramic lining 404 and the heat pipe 401 thus forming a reaction zone. A feed gas inlet 405 and a product gas outlet 406 are provided such that gas is fed to an inlet end of the reactor, passes through the annular gap, and is discharged from an exit end of the reactor. (Slaten 15:7-30). 4. Slaten teaches: The heat pipe mechanism relies on a vapor pressure over the hot liquid working fluid at the hot end of the pipe to be higher than the equilibrium vapor pressure over condensing working fluid at the cooler end of the pipe. It is this pressure difference that drives a rapid mass transfer to the condensing end where the excess vapor condenses and releases its latent heat. The condensed working fluid then flows back to the hot end of the pipe. In the case of vertically-oriented heat pipes the fluid may be moved by the force of gravity. (Slaten 2:65 to 3:6). 5. Claim 1 of Slaten recites, in part, “providing a reaction zone containing a second heat pipe partially disposed in said reactor interior and coated with a first catalyst” (Slaten 16:23-25; claim 1, step (b)). 6. Blackwell teaches “an apparatus, a catalyst arrangement, referred to hereinafter as a ‘catalyst/susceptor’, and a process for preparing HCN by reacting ammonia and a lower alkane in the gas phase in the presence of a platinum group metal catalyst” (Blackwell ¶ 15). Appeal 2021-003132 Application 16/096,493 6 7. Blackwell teaches “a catalyst/susceptor in the form of a cylinder surrounded by an induction coil. The outer diameter of the catalyst/susceptor is preferably as large as possible” (Blackwell ¶ 19). 8. Figure 1 of Blackwell is reproduced below: Figure 1 is a schematic representation which illustrates the principle involved in the present invention. Substantially cylindrical catalyst/susceptor 1 is positioned within a reactor wall 2 which is substantially electrically nonconductive. Said cylindrical catalyst/susceptor 1 is gas-permeable, and has electrical properties (bulk conductivity and continuous conduction paths around the circumference of the cylinder) required to induce eddy currents which can flow in circular paths around and within the annular catalyst/susceptor. An induction coil 3 (typically fluid-cooled) surrounds the catalyst/susceptor 1 and the reactor wall 2. (Blackwell ¶ 25). Appeal 2021-003132 Application 16/096,493 7 Principles of Law A prima facie case for obviousness “requires a suggestion of all limitations in a claim,” CFMT, Inc. v. Yieldup Int’l Corp., 349 F.3d 1333, 1342 (Fed. Cir. 2003) and “a reason that would have prompted a person of ordinary skill in the relevant field to combine the elements in the way the claimed new invention does.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007). Analysis The Examiner finds it obvious to combine the teachings of Slaten and Blackwell because “both teachings are drawn to the use of inductive heating to catalyze the reaction with ammonia with methane and each teaching provides obvious variants that would be expected by the person of ordinary skill in the art to have the same function” (Final Act. 7). The Examiner also finds the claims obvious, in part, because the person of ordinary skill in the art would expect that the coil is touching the heat pipe to provide the largest possible reaction zone and there would be a direct electrical contact from the coil to the catalyst, even if the coil and the heat tube may have different rates of thermal expansion as argued by the Appellant (Ans. 8). Appellant contends the rejection relies on “disparate references for descriptions of separate aspects of claim 1 without articulating a rationale for why a person of ordinary skill in the art would have modified the disclosed processes to arrive at the process of claim 1” (Appeal Br. 11). Appellant contends those skilled in the art would have expected that a heat pipe completely encased within an induction coil would no longer Appeal 2021-003132 Application 16/096,493 8 possess the required “hot end” and “cool end” to drive the vaporization and condensation of the working fluid inside the pipe. The heat pipe would have been expected to possess two “hot ends” instead. Thus, without the heat pipe’s ability to cycle through the vaporization and condensation of the working fluid, those skilled in the art would have expected that the heat pipe could not generate any latent heat and thereby could not supply the energy to the reaction zone needed for the catalytic production of HCN from a feed gas. (Reply Br. 4-5). We find that Appellant has identified an error in the Examiner’s rejection because the combination described in the rejection would reasonably be expected to change the process by which Slaten operated using the condensation mechanism (FF 4) for the reasons stated by Appellant. And while the Examiner is correct that the methods of Slaten and Blackwell are otherwise similar, the difference in mechanisms undercuts the obvious substitution rationale because the device would require changes that allow it to operate using a different mechanism of action. Consequently, the Examiner has provided no persuasive reason, other than simple substitution, to make the modification, and Appellant has persuasivly explained why the substitution would not be simple and necessarily function. “We must still be careful not to allow hindsight reconstruction of references to reach the claimed invention without any explanation as to how or why the references would be combined to produce the claimed invention.” Innogenetics, N.V. v. Abbott Labs., 512 F.3d 1363, 1374 n.3 (Fed. Cir. 2008). Conclusion of Law Appeal 2021-003132 Application 16/096,493 9 A preponderance of the evidence of record does not support the Examiner’s conclusion that Slaten and Blackwell render the claimed method obvious. B. 35 U.S.C. § 103(a) over Slaten, Blackwell, and Hojlund Having reversed the obviousness rejection of claim 1 over Slaten and Blackwell for the reasons given above, we also find that the further combination with Hojlund does not provide reasons or motivation for a modification necessary to render the claim obvious. We therefore reverse this rejection for the same reasons. DECISION SUMMARY In summary: Claims Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 1, 10, 12- 15 103 Slaten, Blackwell 1, 10, 12- 15 1, 4, 6-15 103 Slaten, Blackwell, Hojlund 1, 4, 6-15 Overall Outcome 1, 4, 6-15 REVERSED