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 .
Response to Amendment
Applicant’s amendment filed on October 29, 2025 has been received and carefully considered. The amendment to the specification is acceptable. Claims 1-6 are withdrawn from further consideration. Claims 12-14 are new. Claims 7-14 are under consideration.
Response to Arguments
Applicant's arguments filed on October 29, 2025 have been fully considered.
In particular, Applicant (at page 8, last paragraph, to page 10, first paragraph) argues that the combination of Bachleitner et al. and Kubisa et al. fails to disclose or teach the new limitation of independent claim 7, “wherein the ozone introduced into the aqueous nitric acid-containing solution has a temperature of below 10 °C”. Applicant argues that Kubisa et al. fails to teach the introduction of ozone into the aqueous solution at a temperature below 10 °C.
The arguments are considered persuasive, and therefore, the rejection has been withdrawn. However, upon further consideration, a new ground of rejection is made in view of Bachleitner et al. and the newly cited prior art reference to Steiner et al., detailed below.
It is further noted that Bachleitner et al. (at paragraph [0016]) discloses,
“An advantageous development of the invention provides that, the oxygen, or the oxygen-containing gas, is fed at a temperature below ambient temperature, preferably below 0° C. The invention, in this embodiment proceeds from the knowledge that the exothermic reaction steps proceeding in the riser pipe and subsequently in the absorption tower proceed the more rapidly, the lower the temperature is. By feeding the cold or cryogenic oxygen, the temperature of the reactive mixture is lowered and the reaction rate is hereby accelerated.” (with emphasis added).
Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to introduce the oxidizing agent, as oxygen or ozone, into the aqueous nitric acid-containing solution at a temperature of below 10 °C in the production plant of Bachleitner et al. because the exothermic reaction steps occurring in the riser pipe and subsequently in the absorption tower would be expected to proceed more rapidly at lower temperatures, and by feeding the oxidizing agent into the aqueous nitric acid-containing solution at a low temperature, such as preferably below 0 °C, the temperature of the reactive mixture would be lowered and, accordingly, the reaction rate would be accelerated.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 7-14 are rejected under 35 U.S.C. 103 as being unpatentable over Bachleitner et al. (US 2015/0376010 A1) in view of Steiner et al. (EP 0001834 A1).
The instant “production plant” claims are considered apparatus claims.
Regarding claim 7, Bachleitner et al. (see FIG. 1) discloses a production plant 1 for preparing nitric acid (i.e., as product 17), the production plant 1 comprising:
an ammonia combustion plant 2 (see paragraph [0030]) for reacting ammonia (NH3) with oxygen (O2) to give reaction products comprising nitrogen oxides and steam;
a condenser 3 (see paragraph [0030]) connected to the ammonia combustion plant 2 for cooling the reaction products from the ammonia combustion plant to a temperature at which at least some of the reaction products condense, thereby forming a gas mixture and an aqueous nitric acid-containing solution;
a first absorption tower 4 (see paragraphs [0030]-[0032]) arranged downstream of the condenser 3 for scrubbing the gas mixture formed in the condenser (i.e., supplied from the condenser 3 via a gas feed pipe 11 into a lower region of the absorption tower 4) with water or with the aqueous nitric acid-containing solution (i.e., supplied from the condenser 3 to the absorption tower 4 via riser pipes 12);
a riser conduit (i.e., the riser pipe 12), leading from the condenser 3 to the first absorption tower 4 and equipped with a conveying device (i.e., a transport appliance 13; see paragraph [0030]) for introducing the aqueous nitric acid-containing solution formed in the condenser 3 into the first absorption tower 4; and
a conveying conduit (i.e., an outlet pipe 16; see paragraph [0033]) connecting the first absorption tower 4 to a bleaching column 6;
wherein the riser conduit 12 running between the condenser 3 and the first absorption tower 4 is flow-connected to a source for oxygen 24 via an oxygen supply conduit (i.e., an oxygen feed pipe 29 supplies oxygen to riser pipe 12 from a source of oxygen, such as oxygen from a tank 24 for liquid oxygen, passed through evaporator 25, or oxygen from a pressure vessel for gaseous oxygen, a pipe, or an appliance for air separation, not shown; see paragraph [0035]), whereby oxygen is introduced into the aqueous nitric-acid containing solution.
The production plant 1 of Bachleitner et al. is the same as the claimed plant, except that Bachleitner et al. fails to disclose that the riser conduit 12 is flow-connected to a source for ozone via an ozone supply conduit, whereby ozone (instead of oxygen) is introduced into the aqueous nitric acid-containing solution.
Steiner et al. discloses an apparatus for preparing nitric acid (see Figure; translation) comprising: an absorption tower (i.e., a column 1 which functions as both an oxidation and an absorption reactor) for scrubbing a gas mixture containing nitrogen oxides (i.e., “nitrous gases”, meaning NO, NO2, and mixtures thereof; see paragraph [0005]) with water or an aqueous nitric acid-containing solution (i.e., an “aqueous phase”, intended to mean water and/or nitric acid and oxygen-containing gas; see paragraph [0005]). Specifically, Steiner et al. discloses that an oxygen-containing gas is dispersed in the aqueous nitric acid-containing solution, wherein the oxygen-containing gas comprises “oxygen, ozone, air, etc.” (see paragraph [0005]).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to provide a source for ozone flow-connected to the riser conduit 12 via an ozone supply conduit in the production plant of Bachleitner et al. because ozone would have been considered a suitable alternative oxygen-containing gas to oxygen for dispersing into the aqueous nitric acid-containing solution and accomplishing substantially the same result in producing the nitric acid, as taught by Steiner et al., and the substitution of one known element for another would have yielded predictable results to one of ordinary skill in the art. See MPEP § 2143, I, B.
With respect to the new limitation directed to a temperature of the introduced ozone, Bachleitner et al. (at paragraph [0016]) further discloses,
“An advantageous development of the invention provides that, the oxygen, or the oxygen-containing gas, is fed at a temperature below ambient temperature, preferably below 0° C. The invention, in this embodiment proceeds from the knowledge that the exothermic reaction steps proceeding in the riser pipe and subsequently in the absorption tower proceed the more rapidly, the lower the temperature is. By feeding the cold or cryogenic oxygen, the temperature of the reactive mixture is lowered and the reaction rate is hereby accelerated.” (with emphasis added).
Steiner et al. (see paragraph [0007]) also discloses an example in which the temperature of the aqueous nitric acid-containing solution (the liquid temperature) was maintained at 27 °C. However, Steiner et al. (see paragraph [0009]) further discloses that, “The absorption rate can be increased even further by increasing the pressure and lowering the temperature”.
Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further configure the modified production plant of Bachleitner et al. so as to introduce the ozone into the aqueous nitric acid-containing solution at a temperature of below 10 °C because the exothermic reaction steps occurring in the riser pipe and subsequently in the absorption tower would be expected to proceed more rapidly at lower temperatures, and by feeding the ozone at a low temperature, preferably below 0 °C, the temperature of the reactive mixture would be lowered and, accordingly, the reaction rate would be accelerated, as taught by Bachleitner et al., and it was also recognized that lowering the temperature increases the absorption rate, as taught by Steiner et al.
Regarding claim 8, Bachleitner et al. discloses that the riser conduit 12 can be equipped with a bypass conduit (not shown) into which the oxygen supply conduit 29 opens (i.e., in an advantageous variant, the riser pipe 12 comprises a bypass pipe, and the oxygen feed pipe 29 discharges oxygen into a compressed sub-stream of the nitric acid-containing solution flowing through the bypass pipe; see paragraph [0019]-[0020], [0039]). Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further equip the riser conduit 12 with the bypass conduit into which the ozone supply conduit opens in the modified production plant of Bachleitner et al.
Regarding claim 9, Bachleitner et al. discloses that means for compressing the aqueous nitric acid-containing solution are provided in the riser conduit 12 (i.e., the transport appliance 13 ensures the necessary pressure for overcoming the hydrostatic pressure in the riser pipe 12; see paragraph [0030]) and/or the bypass conduit at least in the region of a mouth of the oxygen supply conduit into the bypass conduit (i.e., the bypass pipe can also be equipped with an appliance for pressure boosting, such that the pressure in the bypass pipe is adjustable to a value higher than the hydrostatic pressure necessary for transporting the nitric acid solution to the top of the absorption tower 12, see paragraphs [0019]-[0020]; the oxygen can be discharged into the compressed sub-stream via a mouth 34 of an oxygen feed pipe 27 arranged in the bypass pipe, see FIG. 2 and paragraph [0039]). Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further configure the ozone supply conduit to open into the bypass conduit in the claimed manner in the modified production plant of Bachleitner et al. because the compressed sub-stream of nitric acid-containing solution which flows through the bypass conduit could be enriched with the ozone and then again fed into the main stream of the nitric acid-containing solution before feeding the nitric acid-containing solution into the absorption tower 4 via the riser pipe 12, and by compressing the sub-stream in the bypass conduit to a pressure that was higher than the hydrostatic pressure necessary for transporting the nitric acid-containing solution from the condenser 3 to the absorption tower 4, the dissolution of the ozone and the formation of nitric acid would be promoted, as suggested by Bachleitner et al. (see paragraphs [0019]-[0020]).
Regarding claim 10, Bachleitner et al. (see FIG. 1) discloses that a transport conduit (i.e., a riser pipe 14) is provided, which leads from a bottom of the first absorption tower 4 into a higher region of the first absorption tower 4 and into which opens a supply conduit (i.e., an oxygen feed pipe 28) that is flow-connected to a source for oxygen (i.e., to the tank 24 for liquid oxygen or other suitable source of oxygen; see paragraph [0035]).
The modified production plant of Bachleitner et al. meets the claim because the supply conduit is merely required to flow-connect to “an additional source of ozone and/or a source for oxygen”. However, as commented above, Steiner et al. discloses that the oxygen-containing gas can comprise “oxygen, ozone, air, etc.” (see paragraph [0005]). Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further flow-connect the supply conduit 28 to an additional source for ozone in the modified production plant of Bachleitner et al. because ozone would have been considered a suitable alternative oxygen-containing gas to oxygen for dispersing into the aqueous nitric acid-containing solution and accomplishing substantially the same result in producing the nitric acid, as taught by Steiner et al., and the substitution of one known element for another would have yielded predictable results to one of ordinary skill in the art. See MPEP § 2143, I, B.
Regarding claim 11, Bachleitner et al. (see FIG. 1) discloses the riser conduit 12 is a first riser conduit; and a second absorption tower 5 is connected downstream of the first absorption tower 4, wherein the second absorption tower 5 is connected to the first absorption tower 4 via a second riser conduit (i.e., a riser pipe 21) leading from the base of the second absorption tower 5 to a headspace of the first absorption tower 4, and wherein a supply conduit (i.e., an oxygen feed pipe 27) that is flow-connected to a source for oxygen (i.e., a tank 24 for liquid oxygen or other suitable source of oxygen; see paragraph [0035]) opens into the second riser conduit 21.
The modified production plant of Bachleitner et al. meets the claim because the supply conduit is merely required to fluidly connect to “an additional source of ozone and/or a source for oxygen” (with emphasis). However, as commented above, Steiner et al. discloses that the oxygen-containing gas can comprise “oxygen, ozone, air, etc.” (see paragraph [0005]). Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further flow-connect the supply conduit 27 to an additional source for ozone in the modified production plant of Bachleitner et al. because ozone would have been considered suitable alternative oxygen-containing gas to oxygen for dispersing into the aqueous nitric acid-containing solution and accomplishing substantially the same result in producing nitric acid, as taught by Steiner et al., and the substitution of one known element for another would have yielded predictable results to one of ordinary skill in the art. See MPEP § 2143, I, B.
Regarding claim 12, Bachleitner et al. discloses that the conveying device (i.e., the transport appliance 13; FIG. 1, paragraph [0030]) is a first conveying device, and the bypass conduit can further comprise a second conveying device (i.e., the bypass pipe can also be equipped with an appliance for pressure boosting (not shown); see paragraphs [0019]-[0020]).
Regarding claim 13, Bachleitner et al. (at paragraph [0037]) discloses,
“The oxygen is introduced in a geodetically lower region of the respective riser pipe 12, 14, 21 and downstream of the respective transport appliance 13, 15, 22 in order to utilize the hydrostatic pressure of the liquid column present in the riser pipe 12, 14, 21 and any additional pressure generated by the respective transport appliance 13, 15, 22.” (with emphasis added).
Bachleitner et al. (at paragraph [0039]) also discloses,
“… oxygen is conducted at high pressure through the oxygen pipe 28, forces the blocking element 31 against the force of the return spring 35 into its open state and flows at high velocity into the region 39 upstream of the mouth opening of the injection appliance 30. As a result, in the inner annular channel 37, a reduced pressure is caused, on account of which nitric acid-containing solution is increasingly conducted through the inner annular channel 37, wherein—as indicated by arrows 40—in addition nitric acid-containing solution is drawn in by suction from the outer annular channel 38 into the inner annular channel 37. In the region 39, on account of the higher open pipe cross section, there is a higher pressure, and intimate mixing of oxygen and nitric acid-containing solution occurs.” (with emphasis added).
Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further provide a pressure reducer device downstream from the second conveying device in the modified production plant of Bachleitner et al. because the pressure reducer device (i.e., the device creating a reduced pressure zone within an inner annular channel of an injection appliance; see FIG. 2) provided downstream from the second conveying device (i.e., to utilize the hydrostatic pressure of the liquid column present in the bypass conduit and any additional pressure generated by the transport appliance of the bypass conduit) would have facilitated an intimate mixing of the ozone and the nitric acid-containing solution in the bypass conduit, as suggested by Bachleitner et al.
Regarding claim 14, Bachleitner et al. discloses that the oxygen supply conduit (i.e., the pipe feeding GOX; FIG. 2) opens into the riser/bypass conduit downstream from the conveying device (i.e., to utilize the hydrostatic pressure of the liquid column in the conduit and any additional pressure generated by the transport appliance; see paragraph [0037]) and upstream from the pressure reducer device (i.e., upstream of the inner annular channel 37). Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to further configure the ozone supply conduit to open into the bypass conduit downstream from the second conveying device and upstream from the pressure reduce device in the modified product plant of Bachleitner et al. because the recited arrangement of the ozone supply conduit would facilitatee an intimate mixing of the ozone and the nitric acid-containing solution in the bypass conduit, as suggested by Bachleitner et al.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: Jaroszynska-Wolinska (Journal of Molecular Structure: THEOCHEM 952 (2010) 74–83) is cited to further illustrate the state of the art.
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.
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Any inquiry concerning this communication or earlier communications from the examiner should be directed to JENNIFER A LEUNG whose telephone number is (571)272-1449. The examiner can normally be reached Monday - Friday 9:30 AM - 4:30 PM EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, CLAIRE X WANG can be reached at (571)270-1051. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JENNIFER A LEUNG/Primary Examiner, Art Unit 1774