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 .
Priority
Acknowledgment is made of applicant’s claim for foreign priority (CN201910826732.9, filed on 02 September 2019) under 35 U.S.C. 119 (a)-(d). Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION. —The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
Claims 1, and 3-8 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites the limitations “the last mother liquor of taurine generated in the ethylene oxide taurine production process” from (a), and “a circulation path for returning filtrate to the ammonia mixing reaction tank” from the Wherein clause. The scope is unclear because the “returning filtrate” can reasonably be read as the “last mother liquor of taurine,” but the claim recites the “last mother liquor of taurine” is received by the upstream activated carbon device while the “returning filtrate” is returned to the ammonia mixing reaction tank. The Specification describes circulating filtrate back to the tank only until the filtrate is clear, and then transferring the material out to the ammonolysis reaction process for recycle (¶[0071]). Accordingly, Claim 1 is indefinite because the flow path is ambiguous. Claim 3–8, which depend on Claim 1, are similarly rejected by virtue of dependency.
Claim 1 recites the limitations “the anion resin adsorption device” and “the last mother liquor” in element (a). There is insufficient antecedent basis for these limitations in the claim. Claims 3–8, which depend from Claim 1, are similarly rejected by virtue of dependency.
Claim 4 recites the limitation “the discharge port” in Claim 4. There is insufficient antecedent basis for this limitation in the claim.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
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 5-8 are rejected under 35 U.S.C. 103 as being unpatentable over XIA et al. (CN105732440A, hereinafter XIA) in view of SUN et al. (US10604478 / CN201910574419 with foreign publication date: June 28, 2019, hereinafter SUN), and JIANG et al. (CN206867843U, hereinafter JIANG).
Regarding Claim 1, XIA discloses taurine production technology directed to fully recovering mother liquor (¶[0002]). Ethylene oxide gas is mixed and reacted with sodium bisulfite in a synthesis tower to obtain sodium hydroxyethyl sulfonate solution, and the sodium hydroxyethyl sulfonate solution is mixed with treated recycled mother liquor and ammonia and pumped into a high pressure synthesis tower via a high pressure plunger pump to obtain sodium taurine solution (¶¶[0020]–[0021]). The sodium taurine solution is processed using a horizontal spiral sedimentation centrifuge to remove byproducts, and the supernatant is subjected to a further centrifugation step to obtain crude taurine, wherein the material is prepared for concentration and desalting (¶[0024]).
The material is heated and concentrated using a steam mechanical compression device (¶[0026]). The filtered material is treated with sodium taurate solution or ammonia water and passed through a plate and frame filter press to obtain sodium sulfate and mother liquor, and all mother liquor after filtration is recovered and used in the synthesis section (¶[0029]). The mother liquor after the secondary extraction of crude taurine by pressure filtration is completely reused (¶[0066]).
It is reasonably interpreted that recovering and reusing the mother liquor in the synthesis section requires a physical conduit structure. Specifically, returning the filtrate from the filter press to the synthesis vessel for the mixing disclosed by XIA requires a return conduit to transport the fluid. Furthermore, the disclosure of “pressure filtration” reasonably encompasses a sealed or closed filter assembly because operating a filter under pressure inherently requires an enclosed housing to maintain the pressure differential and prevent leakage.
However, XIA does not explicitly disclose (b) an anion resin adsorption device for adsorbing the anions of taurine and sodium isethionate, wherein the anion resin adsorption device includes an anion exchange resin column.
SUN discloses taurine production technology directed to producing taurine and to removing impurities from a taurine reaction system (Col. 1, Lns. 17 to 20). A reaction solution comprising alkali metal taurinate and or alkali metal isethionate is passed through a column of basic anion exchange resin to adsorb anions and obtain an eluate comprising at least one impurity. The adsorbed anions are desorbed with an alkaline solution to obtain a desorption liquid comprising alkali metal taurinate and or alkali metal isethionate (Col. 1, Lns. 47 to 64). The basic anion exchange resin adsorbs anions of both alkali metal taurinate and alkali metal isethionate from mother liquor obtained after taurine separation in the ethylene oxide method (Col. 4, Lns. 1 to 6). In another aspect, the desorption liquid is fed into the reaction system for producing taurine (Col. 5, Lns. 31 to 46).
A person skilled in the art seeking to implement an ethylene oxide taurine production process with mother liquor recycle starting with XIA’s disclosure would have recognized the same issue as disclosed in SUN, that byproducts and impurities remain in the mother liquor after taurine separation, limiting recycle and reducing productivity while increasing taurine production cost (Col. 2, Lns. 33–48). SUN addresses removal of such impurities from a taurine reaction system using a basic anion exchange resin column (Col. 1, Lns. 47–64). The impurities are removed without the use of organic solvents, resulting in taurine of high purity and high yield (Col. 3, Lns. 36–40).
Therefore, it would have been obvious to a person having ordinary skill in the art, prior to the effective filing date of the claimed invention, to incorporate the impurity removal by basic anion exchange resin column, as disclosed by SUN, upstream of the ammonia mixing and desalination stage of the taurine production system by XIA.
However, modified XIA does not explicitly disclose (a) an activated carbon decolorization and impurity removal device located upstream of an anion resin adsorption device, the activated carbon decolorization and impurity removal device including a decolorization tank and a filter for treating a last mother liquor stream.
JIANG discloses a decolorization filtration system (¶[0002]). The system includes a reactor vessel containing a decolorizing agent and a leaf filter, wherein a transfer pump conveys liquid from the reactor vessel to the leaf filter and a filtrate return pipe returns filtrate from the leaf filter to the reactor vessel (¶[0015]). The decolorizing agent in the reactor vessel is activated carbon (¶[0018]).
Advantageously, the decolorization and filtration system improves decolorization and filtration efficiency by separating decolorization and filtration and enabling cyclic processing (¶[0011]). The system reduces residual filtrate and waste and avoids cumbersome filter residue cleaning that is not conducive to continuous production (¶[0012]). The decolorizing agent is activated carbon having a large specific surface area and strong adsorption capacity (¶[0030]).
A person skilled in the art would have understood that placing the activated carbon decolorization and filtration system upstream of the anion exchange resin column reduces the impurity load entering the resin column, thereby avoiding fouling and chemical degradation of the resin, and that it would have been obvious to recirculate the mother liquor from XIA’s synthesis system to the activated carbon decolorization system by JIANG until it is clear for reuse.
Regarding ports and connections, JIANG discloses that the reaction vessel has an inlet and an outlet and the filter has an inlet and an outlet (¶[0015]). SUN discloses passing a solution through a column (Col. 1, Lns. 47 to 64), which requires an inlet and an outlet to function. While the combined devices are drawn from multiple references, inlets and outlets are inherent features of any fluid transport system conveying process liquid between stations. A flow through system cannot function without inlets and outlets, and configuring these ports to enable fluid communication between the decolorization and filtration system of JIANG, the basic anion exchange resin column system of SUN, and the ammonia mixing and filtration station of XIA is a necessary design requirement to implement the claimed system.
Therefore, it would have been obvious to a person having ordinary skill in the art, prior to the effective filing date of the claimed invention, to incorporate the activated carbon decolorization and filtration system, as disclosed by JIANG, upstream of the basic anion exchange resin column, in the taurine production system by modified XIA.
Regarding Claim 5, modified XIA makes obvious a taurine production system of Claim 1. SUN discloses passing a reaction solution comprising taurinate and or isethionate through a basic anion exchange resin column to adsorb anions, eluting the anions with an alkaline solution to obtain a desorption liquid, and feeding the desorption liquid into the taurine reaction system (Col. 5, Lns. 31–46). In Example 1, a basic anion exchange resin column is regenerated by passing a sodium hydroxide solution through the resin and monitoring pH of an effluent, and eluate obtained during the regeneration may be delivered to a storage tank (Col. 6, Lns. 36–67).
Regarding the limitation “a regeneration feed valve,” it would have been obvious to include a valve on the alkaline liquid feed line as a routine design choice to control addition of the alkaline liquid to the anion exchange resin column during regeneration.
Regarding the limitation “a receiving tank having an outlet connected to a feed port of the ammonia mixing and desalination device,” the storage tank receiving the eluate from regeneration is necessarily provided with an outlet to discharge the collected liquid, and connecting that outlet to the downstream feed port is a routine piping arrangement to return the collected stream to the process.
Regarding Claim 6, modified XIA makes obvious a taurine production system of Claim 5. XIA discloses pumping process liquid into the high pressure synthesis tower via a high pressure plunger pump (¶¶[0020]–[0021]). the synthesis tower receives ammonia, sodium isethionate, and recycled mother liquor through dedicated inlets ([0025]). The outlet of the synthesis tower is connected to a centrifuge that removes solids from the liquid stream ([0036]). The recycled mother liquor is heated and concentrated using steam mechanical recompression and then returned to the synthesis tower through a circulation path ([0044]). The mother liquor after the secondary extraction of crude taurine by pressure filtration is completely reused (¶[0066])
JIANG discloses a transfer pump for conveying liquid from a reactor vessel to a filter (¶[0015]), and a first valve provided between the discharge port of the reactor and the transfer pump to control flow from the reactor to the pump (¶[0019]).
Regarding the limitation “said pump provided with a transfer discharge valve for discharging filtered material,” it would have been obvious to provide a discharge valve on the pump as a routine flow control component to control discharge of the transferred liquid.
Regarding Claim 7 and 8, modified XIA makes obvious a taurine production system of Claim 1. JIANG discloses the reactor vessel is equipped with a stirring device and a steam jacket on the outside of the reactor vessel (¶[0020]). Although JIANG describes the jacket as a steam jacket, a person skilled in the art would have understood that the tank jacket is used for temperature control, and the jacket can be supplied with either a heating medium or a cooling medium to maintain the tank at a desired temperature.
Claims 3-4 are rejected under 35 U.S.C. 103 as being unpatentable over XIA in view of SUN and JIANG as applied to claim 1 above, and further in view of JANGBARWALA et al. (US5951874A, hereinafter JANGBARWALA).
Regarding Claim 3 and 4, modified XIA makes obvious a taurine production system of Claim 1. However, modified XIA does not explicitly disclose a cationic resin adsorption device connected to the downstream end of the activated carbon decolorization and impurity removal device and adapted for reducing the pH of the last mother liquor of taurine, wherein the cationic resin adsorption device comprises a raw material tank and a cation exchange resin column, the raw material tank is connected to the discharge port of the activated carbon decolorization and impurity removal device, and the cation exchange resin column is connected to the anion exchange resin column.
JANGBARWALA discloses a technology to significantly reduce overall waste volume generated in deionization or demineralization systems (Col. 2, Lns. 33–45). In such systems, ion exchange removes objectionable ions by exchanging cations and anions for hydrogen ions and hydroxyl ions (i.e., adapted for reducing the pH; Col. 1, Lns. 14–20).
In Embodiment 1, a basic deionizing and regenerating system uses counter-current down-flow regeneration. Service flow is performed in an up-flow direction via a collection sump, a pump, a filter, a granular activated carbon bed, a cation exchange bed (strong acid), and an anion exchange bed (strong base) to a service outlet. Backwash for the cation and anion exchange beds is performed in an up-flow direction in a loop returning to the collection sump, whereby divalent cation is removed prior to entering the anion exchange bed, and regeneration is performed using HCl from an acid tank (Col. 11, Lns. 28–56).
A person skilled in the art would recognize the significance of JANGBARWALA’s disclosure that placing a cation exchange bed upstream of an anion exchange bed avoids precipitation and fouling in the anion resin (Col. 6, Lns. 21–30), and that installing a chelated metal removal column, a granular activated carbon column, and a filtration device upstream of the cation column further minimizes waste volume (Col. 6, Lns. 37–42). It would have been beneficial to include a cation exchange resin column before the anion exchange resin column not only to avoid precipitation and fouling in the anion resin, but also to exchange cations for hydrogen ions to optimize the pH condition of the stream for anion exchange.
Regarding to the limitation “the cationic resin adsorption device comprises a raw material tank” and “the raw material tank connected to the discharge port,” it would be obvious to include a raw material tank, like the collection sump disclosed by JANGBARWALA, to provide storage, regulate flow between the activated carbon and cation exchange stages. In fluid treatment systems, intermediate tanks are commonly used for buffering, flow control, and isolating unit operations, and a person skilled in the art would recognize such placement as a routine structural consideration.
Therefore, it would have been obvious to a person having ordinary skill in the art, prior to the effective filing date of the claimed invention, to incorporate a cationic resin adsorption device upstream of an anion exchange resin column, as disclosed by JANGBARWALA, in the taurine production system by modified XIA.
Response to Arguments
Applicant’s arguments, see REM, filed October 21, 2025, with respect to the rejection(s) of claim(s) 1–6 under 35 U.S.C. § 103 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground of rejection is made under 35 U.S.C. § 103 in view of XIA et al., SUN et al., JIANG et al., and JANGBARWALA et al.
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 TAK L. CHIU whose telephone number is (703)756-1059. The examiner can normally be reached M-F: 9:00am - 6:00pm (CST).
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/TAK L CHIU/Examiner, Art Unit 1777
/KRISHNAN S MENON/Primary Examiner, Art Unit 1777