DETAILED ACTIONNotice 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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
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 1 and 4-7 are rejected under 35 U.S.C. 103 as being unpatentable over Gu et al. 2021, CN 214991237 U, in view of Duan et al. 2010, CN 201578978 U, Zhang 2012, CN 202136979 U, Hunter et al. 1995, US 5406828 A, Schenker 2010, US 20100255588 A1, and Zhou, 2019, CN 209076071 U, and evidenced by page 9 of The Nitrogen Industry by James Riddick Partington, Leslie Henry Parker Constable, 1922. Machine translations of Gu, Duan, Zhang, and Zhou are provided with this Office action and cited herein.
Regarding claim 1, Gu teaches a nitrogen stripping device (0007) comprising:
a mixer (venturi mixer 230, Fig. 1; all reference labels defined in paragraph 0018),
a temperature-controlled column (gas-liquid separator 240, Fig. 1; “predetermined temperature” of the entirety of device 200, 0022),
wherein the mixer is configured for mixing a nitration reaction liquid (line from heater 252 to mixer 230, which is supplied by line from nitration reaction device 100, Fig. 1; see 0022 and 0037) and nitrogen (line 260, Fig. 1; “nitrogen entering the first venturi mixer 230,” 0037), and feeding a nitration reaction liquid-nitrogen gas mixture into the column through a first pipeline (pipe from mixer 230 into 240, Fig. 1);
the lower portion of the column is filled with a mass-transfer enhancement member (the outlet end of the first Venturi mixer 230, 0037) for dispersing the nitration reaction liquid and increasing a contact area between the nitrogen gas and the nitration reaction liquid to ensure that volatile materials are taken away by the nitrogen gas (it is inserted below the liquid surface in order to generate an aeration effect, thereby further improving the nitrogen stripping effect, 0037); a top end of the column is connected to the mixer (Fig. 1), and a bottom port of the column is connected to a storage tank (drying and separation device 500, Fig. 1) through a second pipeline (line 220, Fig. 1); the storage tank is configured to receive a nitric acid-free reaction liquid (neutral nitration liquid D, 0030) which is produced by removing nitric acid from the nitration reaction liquid (0029-0030); and a pump is provided on the second pipeline to transfer the nitric acid-free reaction liquid to the storage tank (pump 251, Fig. 1);
a top port of the column is connected to a condensing device (nitric acid recovery device 600) through a third pipeline (line 210 to device 600, Fig. 1), such that waste gas and nitric acid are discharged from the top port of the column to the device through the third pipeline to allow recovery of nitric acid (0032);
Gu does not teach:
The device being an on-line continuous evaporation device for on-line continuous recovery of nitric acid in a nitration reaction;
A temperature-controlled corrosion-resistant column;
A metering pump and compressed air cylinder;
A flow rate of the nitrogen gas is adapted to be controlled by a gas flow meter
The temperature-controlled corrosion-resistant column has a double-layer structure comprising an inner layer and an outer layer; the inner layer is a hollow column;
A top port of the inner layer is connected to a condensing device through the third pipeline;
A gap is provided between the inner layer and the outer layer, and is configured to allow a heat transfer fluid to flow through; and an upper portion of the outer layer is provided with an outlet of the heat transfer fluid, and a lower portion of the outer layer is provided with an inlet of the heat transfer fluid.
However, regarding limitation I, it would be obvious to one skilled in the art that the device is an on-line continuous evaporation device, capable of on-line continuous recovery of nitric acid in a nitration reaction, from Figure 1. Figure 1 clearly shows that the device is not a batch process device but rather is capable of continuous flow of material through the pipe network disclosed, and therefore meets the limitation of an on-line continuous device that conducts evaporation via separator 240 and line 210.
Regarding limitation II, Gu does not teach that the column is corrosion-resistant. However, Duan teaches an analogous device for denitrification (0021) wherein the materials used for parts that come into contact with sulfuric acid and/or nitric acid are made of a corrosion-resistant material such as PFTE (0021). It would be obvious to one skilled in the art to implement the invention of Gu by using a corrosion-resistant material as suggested by Duan; one would be motivated to do so in order to avoid corrosion of the invention, so that is can be used safely for a long time, as Duan teaches (0021).
Regarding limitation III, Gu does not teach a metering pump delivering a nitration reaction liquid, nor a compressed air cylinder supplying nitrogen gas. However, Zhang teaches a nitration reaction vessel capable of external circulation (0007) comprising a metering pump 6 at the outlet of the vessel (0014). It would be obvious to modify the invention of Gu and Duan by using a metering pump as suggested by Zhang; one would be motivated to do so in order to form a continuous system, as Zhang teaches (repeated cycle, 0014), which contributes to saving energy, as Zhang teaches (0009). Furthermore, the provision of nitrogen gas from a compressed cylinder is known in the art as a way to provide nitrogen, which would be prima facie obvious to one skilled in the art; see MPEP 2143(I)(E) regarding the obviousness for one skilled in the art to choose an implementation from a finite number of identified, predictable solutions with reasonable expectation of success; KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007). In the instant case the technology of providing nitrogen gas from a compressed gas cylinder is established and a predictable technology in the art, as evidenced by Partington (“nitrogen… is then compressed into steel cylinders at 100 atm for sale,” p. 9).
Regarding limitation IV, Hunter teaches a bubbler system for introducing nitrogen gas (C3/L30-35) and adjustable spring-biased comparitors for regulating the flow rate of the compressed gas (L36). It would be obvious to one skilled in the art to modify the invention of Gu, Duan, and Zhang, by controlling the flow rate of the nitrogen gas as Hunter teaches; one would be motivated to do so in order to achieve a rate suitable for bubbling, as Hunter teaches (C3/L36), in order to bubble the nitrogen through the material, as Gu teaches (0029).
Regarding limitations V and VII, Schenker teaches a temperature-controlled column (reaction calorimeter, 0002) wherein the column has an inner and outer layer and the inner layer is a hollow column (double-walled reactor jacket, 0035); and a gap is provided between the inner layer and the outer layer, and is configured to allow a heat transfer fluid to flow through (“filled with a fluid temperature-control medium,” 0035); and an upper portion of the outer layer is provided with an outlet of the heat transfer fluid, and a lower portion of the outer layer is provided with an inlet of the heat transfer fluid (connectors 311, Fig. 2; 0054). It would be obvious to one skilled in the art to modify the invention of Gu, Duan, Zheng, and Hunter with the teaching suggested by Schenker; one would be motivated to do so in order to control the temperature of the reaction, as Schenker teaches is an advantage of the invention (0009), since Gu teaches that the temperature of the stripping must be controlled at 75-85 C(0029). It would therefore be obvious to one skilled in the art to combine the teachings of Gu, Duan, Zheng, and Hunter with the teaching of Schenker, where the outlets are implemented at any position of the heating jacket outer layer including an outlet at an upper portion of the outer layer and an inlet at a lower portion of the outer layer, as instantly claimed.
Regarding limitation VI, Zhou teaches a distillation device for treating nitrated waste acid (0018) comprising a condenser (condenser 9, 0033) and a storage unit (collection cylinder 7, 0032). It would be obvious to combine the teachings of Gu, Duan, Zheng, Hunter, and Schenker with the condenser suggested by Zhou; one would be motivated to do so in order to collect the dilute nitric acid, as Zhou teaches (0032), in order to recycle and reuse the nitric acid of the invention (0032) which reduces the content in wastewater and reduces costs of treating wastewater, as Zhou teaches (0032).
One of ordinary skill in the art would therefore arrive at the claimed invention prior to the effective filing date with a reasonable expectation of success.
Regarding claim 4, Gu teaches that the length of the first pipeline extending into the column is a result effective variable, since it must be a length to be inserted below the liquid surface of the liquid phase of the separator (0037); therefore one skilled in the art would recognize that the length of the pipeline is a critical parameter subject to optimization. Further, Gu teaches that gas-liquid separation happens in the gas-liquid separator (0037), therefore teaching that some volatile (i.e. gaseous) materials are taken away while the liquid phase remains in the liquid phase and therefore is not volatized. Thus, one of ordinary skill in the art would have optimized, by routine experimentation, the length of the first pipeline in Gu to obtain the desired balance between the volatization of some materials and liquid separation of other materials as taught by Gu (gas-liquid separation, 0037) (In re Boesch, 617 F.2d. 272, 205 USPQ 215 (CCPA 1980)), and arrive at a value that falls within the claimed range, since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). “[W]here 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.”
Regarding claim 5, Duan teaches PFTE as discussed above.
Regarding claim 6, Gu teaches a method for on-line continuous recovery of nitric acid in nitration reaction through the device of claim 1 (0016) comprising:
feeding the nitration reaction liquid and the nitrogen gas into the mixer at the same time followed by mixing (0037);
transporting a mixture of the nitration reaction liquid and the nitrogen gas to the temperature-controlled corrosion-resistant column for on-line continuous evaporation, wherein the nitration reaction liquid enters into the inner layer from a top end of the temperature-controlled corrosion-resistant column (Fig. 1);
discharging the waste gas and the nitric acid from the top port of the column (Fig. 1), and
discharging the nitric acid-free reaction liquid from the bottom port of the column through the pump (Fig. 1); and storing the nitric acid-free reaction liquid for subsequent treatment (0025).
Gu, modified by Duan, Duan, Zheng, Hunter, Schenker, and Zhou, teaches the device as applied to claim 1 above. Therefore the prior art teaches:
(2) performing heat exchange through a jacket between the inner layer and the outer layer; and controlling a temperature of the heat exchange at 20-150°C (Gu, temperature of 75℃～85℃, 0016) and a flow rate of the heat exchange by a temperature control machine (Schenker, 0012);
discharging the waste gas and the nitric acid from the top port (Gu, Fig. 1) of inner layer (Schenker Fig. 2) of the temperature-controlled corrosion-resistant column (Duan 0021), and recovering the nitric acid through the condensing device (Zhou 0032);
discharging the nitric acid-free reaction liquid (Gu 0030) from the bottom port of the inner layer (Gu Fig. 1) of the temperature-controlled corrosion-resistant column through the pump (Gu Fig. 1); and storing the nitric acid-free reaction liquid for subsequent treatment (Gu 0025).
Gu, Duan, Duan, Zheng, Hunter, Schenker, and Zhou do not teach:
a flow rate ratio of the nitration reaction liquid to the nitrogen gas is set to 1.0:1.0-30.0;
However, when faced with a mixture, one of ordinary skill in the art would be motivated by common sense to select a 1:1 ratio, a ratio that falls within the presently claimed amount, absent evidence of unexpected or surprising results. Case law holds that "[h]aving established that this knowledge was in the art, the examiner could then properly rely... on a conclusion of obviousness, 'from common knowledge and common sense of the person of ordinary skill in the art within any specific hint or suggestion in a particular reference.'" In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969). Therefore it would be reasonably obvious to one of ordinary skill in the art to arrive at the presently claimed invention.
Regarding claim 7, Gu teaches the nitration reaction apparatus 100 (0027) where it is depicted in Figure 1 as a “flowchart” and as a “pipeline” (0017); while Gu does not explicitly teach that the reactor 100 is a continuous flow reactor, the Examiner interprets the flowchart and language used by Gu to meet the limitation of a continuous flow reactor, since it would be sufficiently obvious to one skilled in the art that the “flowchart” and “pipeline” taught by Gu can be implemented as a continuous flow. Gu further does not teach a stopping of the process taught and does not teach a closed system or a closing of any pipelines to implement the system as a batch system.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Gu, in view of Duan, Zhang, Hunter, Schenker, and Zhou, as applied to claim 1, and in further view of Ohkawa et al., Flow and mixing characteristics of σ-type plate static mixer with splitting and inverse recombination; Chem. Eng. Res. Des., 86 (2008), pp. 1447-1453.
Regarding claim 2, Gu, Duan, Duan, Zheng, Hunter, Schenker, and Zhou teach the invention as applied to claim 1. They do not teach that the mixer has a plate-type structure with an interdigital configuration, a Caterpillar configuration or a split-and-recombine configuration.
However, Ohkawa teaches a mixer (Fig. 1) comprising a plate-type structure (Fig. 2) with a split-and-recombine configuration (Fig. 2; “split-and-recombine,” p. 1448 paragraph 1). It would be obvious to one skilled in the art to modify the invention taught by Gu, Duan, Duan, Zheng, Hunter, Schenker, and Zhou by using the mixer taught by Ohkawa as the mixer; one would be motivated to do so in order to keep the mixing of the materials as fast as possible in order for the reactions to proceed at their intrinsic rates, as Ohkawa teaches (Introduction), and the mixer taught by Ohkawa is inexpensive (p. 1448 paragraph 1). One skilled in the art would therefore arrive at the claimed invention prior to the effective filing date.
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Gu, in view of Duan, Zhang, Hunter, Schenker, and Zhou, as applied to claim 1, and in further view of Romatier et al. 2001, US 6299845 B1.
Regarding claim 3, Gu, Duan, Duan, Zheng, Hunter, Schenker, and Zhou teach the invention as applied to claim 1. They do not teach that the mass-transfer enhancement member is a Z-shaped flow-disturbing plate, a horizontal corrugated plate, a vertical corrugated plate, or a 45°-inclined corrugated plate.
However, Romatier teaches a distillation column (C2/L65) containing corrugated plates (C3/L25) which are used to enhance mass transfer (C5/L10-15). It would be obvious to one skilled in the art to combine the teachings of Gu, Duan, Duan, Zheng, Hunter, Schenker, and Zhou with the teaching of Romatier; one would be motivated to do so in order to enhance mass transfer of the materials in the column by increasing the surface area of the materials, as Romatier teaches (“increasing surface area,” C5/L13), in order to promote mixing of the vapor and liquids, as Romatier teaches (C5/L8). Therefore one skilled in the art would arrive at the claimed invention prior to the effective filing date.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Gu, in view of Duan, Zhang, Hunter, Schenker, and Zhou, as applied to claim 1, and in further view of Rogeryermaw on the Sciencemadness Discussion Board, 2014, Can I store nitric acid safely?, The art and science of amateur experimentalism, 9-7-2008, referred to herein as Rogeryermaw.
Regarding claim 8, Gu, Duan, Zheng, Hunter, Schenker, and Zhou teach the invention as applied to claim 6. They do not teach a cooling temperature of the condensing device is controlled to -20-0°C.
However, Rogeryermaw teaches that the storage of nitric acid is unstable at temperatures above and including -10, where one skilled in the art would reasonably understand that -10 is given in units of Celsius (p. 7 paragraph 1). It would therefore be obvious to one skilled in the art to conduct the condensing of nitric acid at a range of temperature around the value of -10 C taught by Rogeryermaw, and arrive at the claimed invention falling within the range of -20 to 0 C; one would be motivated to do so in order to store the nitric acid long term, as Rogeryermaw teaches (several months, every couple of weeks, paragraph 1 of p. 7), since Zhou teaches a distillation device for treating nitrated waste acid (0018) comprising a condenser (condenser 9, 0033) where the condensing sends nitric acid to be stored (collection cylinder 7, 0032). One skilled in the art would reasonably expect to conduct the condensing at a temperature taught to provide stable nitric acid, as Rogeryermaw teaches, and arrive at the claimed invention, prior to the effective filing date of the current invention.
Conclusion
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/Eileen Moudou/ Examiner, Art Unit 1738
/MICHAEL FORREST/ Primary Examiner, Art Unit 1738
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