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 (EP20383135.9, filed on 22 December, 2020) under 35 U.S.C. 119 (a)-(d). Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Claim Objections
Claim 6 objected to because of the following informalities:
The phrase “by cooling or compression a gas mixture sample under pressure” should be corrected to read “by cooling or compressing a gas mixture sample under pressure” for correct use of a verb.
Claim 6 objected to because of the following informalities:
The phrase “comprising(C6-C12)alkyl” should be corrected to read “comprising_(C6-C12)alkyl” because a space is missing.
Appropriate correction is required.
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 7 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 7 recites the limitation “the refrigerant is a hydrofluorocarbon selected from...”. The limitation is indefinite because not every listed refrigerant is a hydrofluorocarbon. For example, claim 7 identifies R-406A as including R-22, R-600a, and R-142b, where R-22 and R-142b are chlorine-containing compounds and R-600a is isobutane. Thus, it is unclear whether the claim is limited to hydrofluorocarbon refrigerants or includes the listed refrigerant blends that are not hydrofluorocarbons. For examination purposes, the claim is interpreted as being limited to the listed refrigerants that are hydrofluorocarbons.
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:
Determining the scope and contents of the prior art.
Ascertaining the differences between the prior art and the claims at issue.
Resolving the level of ordinary skill in the pertinent art.
Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 3-4, 8-14, and 16 are rejected under 35 U.S.C. 103 as being unpatentable over SCHLAKE et al. (US20180345175A1, hereinafter SCHLAKE) in view of Reversed Phase Chromatography Principles and Methods (1999, hereinafter RPC Handbook) and CUI et al. (Reversed-phase high-performance liquid chromatography using enhanced-fluidity mobile phases, 1995, hereinafter CUI).
Regarding Claim 3, SCHLAKE discloses a liquid chromatographic separation system for separating an analyte from a sample using a liquefied gas mobile phase that remains as a single-phase liquid during elution (¶[0002]).
The system is applicable to analytical, semi-preparative, preparative, and flash chromatography using prepacked sorbent cartridges in place of hand-packed columns (¶[0014]). Chromatography column 152 contains a pre-loaded stationary phase, which may be a C18 silica-based adsorbent or another suitable adsorption material (¶[0048]).
The liquefied CO₂ and miscible organic solvent are maintained as a single-phase liquid mobile phase by applying back pressure in chromatography vessel 152 greater than the vapor pressure of CO₂ at the operating temperature. Back pressure regulator 170 sets pressure P₂, preferably above 60 bar. In one example, with an 80 bar CO₂ source and a flowrate of 60 ml/min, a pressure of about 65 bar maintained single-phase conditions and yielded good separation. The system operates below the CO₂ critical temperature of 31°C, and suitable P₂ values are preferably between 50 and 80 bar (¶[0035]).
At 65 bar and 20°C, liquid CO₂ and typical organic solvents remain fully miscible as a single-phase mobile phase across the full CO₂ concentration range. This eliminates phase-separation issues common in SFC systems at elevated temperatures, which exhibit two-phase behavior and reduced separation performance (¶[0038]). The reported process temperature of 20°C reads upon the claimed temperature range of 10 to 60°C.
Back pressure regulator 170 is positioned downstream of chromatography vessel 152 and maintains an upstream process pressure P₂ sufficient to keep the chromatographic fluid in liquid form during elution. The setpoint of the regulator is controlled by controller 171, and the actual pressure at the outlet of the chromatography vessel is measured by sensor 161. Controller 171 and sensor 161 may be operably connected to programmable controller 200, which compares the actual pressure with the preprogrammed setpoint and adjusts the regulator to maintain the desired pressure during operation (¶¶[0056]–[0057]).
The separated eluate is directed to fraction collector 190, which is controlled by programmable controller 200. The controller automatically directs the liquid mobile phase to waste or to one or more collection vials based on peak detection by detector 160 (¶[0061]).
However, SCHLAKE does not explicitly disclose operating the preparative chromatographic system as RP-HPLC using an aqueous mobile phase comprising an organic solvent.
RPC Handbook discloses that reversed phase chromatography is a high-resolution chromatographic technique, and the introductory material leads into the theory of reversed phase chromatography (Pg. 5).
In Theory of reversed phase chromatography, reversed phase chromatography depends on reversible adsorption/desorption between solute molecules and a hydrophobic stationary phase. The initial mobile phase conditions are primarily aqueous, and solute distribution depends on the hydrophobicity of the solute and the composition of the mobile phase. The polarity of the mobile phase is controlled by adding organic modifiers such as acetonitrile, and bound solutes are desorbed by decreasing the polarity of the mobile phase through increasing the percentage of organic modifier in the mobile phase (Pg. 6–8).
In Chapter 3, Choice of mobile phase, the mobile phase generally contains an organic modifier, and the organic solvent is selected to control mobile-phase polarity and eluting power. The organic solvent is added to lower the polarity of the mobile phase, and lower polarity provides higher eluting power in reversed phase chromatography. Water-miscible organic solvents may be used, including acetonitrile, ethanol, methanol, 1-propanol, and 2-propanol (Pg. 44–45).
The RP-HPLC system and aqueous-organic mobile phase disclosed by RPC Handbook were well-known choices for high-resolution separation, since the hydrophobic stationary phase provides selective retention and the organic modifier controls polarity, eluting power, retention, and resolution. In view of SCHLAKE’s chromatographic system including a hydrophobic C18 silica-based stationary phase, a person skilled in the art would have operated the system as RP-HPLC using the aqueous-organic mobile phase to apply the known hydrophobic interaction separation mechanism of RP-HPLC.
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 apply the RP-HPLC separation mode and aqueous-organic mobile phase, as disclosed by RPC Handbook, to the pressure-controlled liquid chromatographic separation process by SCHLAKE.
However, modified SCHLAKE does not explicitly disclose maintaining the gas mixture liquefied sample and the eluting components in liquid form by applying pressure based on a vapor-pressure value at the process temperature.
CUI discloses reversed-phase HPLC using enhanced-fluidity mobile phases, in which CO₂ is added to methanol-water mobile phases to lower plate heights and analysis time without losing mobile-phase solvent strength (Abstract, Pg. 151).
In Chromatographic system, enhanced-fluidity HPLC maintains column pressure above a minimum pressure to avoid the mobile phase mixture separating into two phases, liquid-gas. A flow restrictor after the detector controls the linear velocity in the column, and the necessary column outlet pressure varies with the CO₂ mole fraction in the mobile phase (Pg. 153).
In Materials, methanol-water-CO₂ mixtures are prepared by adding liquid CO₂ to a methanol-water mixture using syringe pumps. The final solution is pressurized to 204 atm and equilibrated at 25°C before use (Pg. 153–154).
In Time of analysis, the methanol-water mobile phase with added CO₂ shortened analysis time compared to methanol-water alone, including by factors of 2.5 and 8 at tested linear velocities (Pg. 161).
Advantageously, the pressure-maintained RP-HPLC operation disclosed by CUI maintains the mobile phase above a minimum pressure to avoid liquid-gas phase separation, and the resulting methanol-water-CO₂ mobile phase decreases plate height across the tested velocity range, especially at higher velocities, improving chromatographic efficiency (Chromatographic system, Pg. 153; Chromatographic efficiency, Pg. 156–158).
In view of modified SCHLAKE’s pressure-controlled RP-HPLC separation process using an aqueous-organic mobile phase, a person skilled in the art would have maintained the CO₂-containing liquefied sample and eluting components under pressure during RP-HPLC to preserve liquid-phase operation and improve chromatographic efficiency, with predictable operation based on the pressure-maintained RP-HPLC principle.
Regarding the limitation “the highest value among these vapor pressure values,” selecting the highest vapor pressure value is a routine pressure-control condition for maintaining the gas mixture liquefied sample and the eluting components in liquid form at the process temperature. Since the highest vapor pressure value represents the controlling pressure threshold for the most volatile component or mixture condition, a person skilled in the art would have selected that value to maintain liquid-phase operation during the pressure-controlled RP-HPLC separation.
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 apply the pressure-maintained RP-HPLC operation principle, as disclosed by CUI, to the pressure-controlled RP-HPLC separation process by modified SCHLAKE.
Regarding Claim 4, modified SCHLAKE makes obvious the process for separating a gas mixture liquefied sample of Claim 3. SCHLAKE uses liquefied CO₂ as the liquefied gas mobile phase, and CO₂ is a known refrigerant designated R-744 in industrial refrigeration systems.
Regarding Claim 8, modified SCHLAKE makes obvious a process for separating a gas mixture liquefied sample of Claim 3. SCHLAKE discloses an available source 120 of liquid CO₂ supplied at chromatography pressure P₂ between about 50 bar and 100 bar and at temperatures below the critical temperature so that CO₂ is present as a liquid prior to separation (¶¶[0033]–[0035], [0038]). A person having ordinary skill in the art would understand that commercial liquid CO₂ and other liquefied gas mixtures are prepared from gas mixtures by cooling or compression under pressure to condense the gas.
Regarding Claim 9, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 3. RPC Handbook discloses that the initial mobile phase conditions are primarily aqueous and that the polarity of the mobile phase is controlled by adding organic modifiers. Bound solutes are desorbed by decreasing the polarity of the mobile phase through increasing the percentage of organic modifier in the mobile phase (Theory of reversed phase chromatography; Pg. 6–8).
Regarding Claims 10–11, modified SCHLAKE makes obvious the process for separating a liquefied gas sample of Claim 9. RPC Handbook discloses that the organic solvent is added to lower the polarity of the mobile phase, and lower polarity provides higher eluting power in reversed phase chromatography. A large number of water-miscible organic solvents may be used, and Table 6 lists typical solvents used in reversed phase chromatography, including 1-propanol (Chapter 3, Methods, Choice of mobile phase; Pg. 44).
Regarding Claim 12, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 3. SCHLAKE discloses that the solvent feed system may operate in an isocratic mode (¶[0040]). Isocratic operation is not equipment-dependent and is applicable to RP-HPLC because it refers to maintaining a constant mobile-phase composition during chromatographic separation.
Regarding Claim 13, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 3.
SCHLAKE discloses a chromatographic system for analytical, semi-preparative, and preparative chromatography in which chromatography column 152 contains a stationary phase (¶¶[0014], [0048]).
Flow of the liquid mobile phase eluate from chromatography column 152 passes through detector 160 and pressure sensor 161 that measures the outlet pressure, and then continues to back pressure regulator 170 positioned downstream of the chromatography vessel to maintain the upstream process pressure P₂ during elution (¶¶[0056]–[0057]).
The downstream back-pressure valve and pressure indicator arrangement is not specific to a particular type of HPLC and remains applicable to RP-HPLC, since controlling and monitoring column pressure is a well-known operation during chromatographic separation.
Regarding Claim 14, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 3. SCHLAKE discloses that eluate from chromatography column 152 passes to detector 160, which monitors the separated components and detects peaks. Programmable controller 200 uses the detector information to direct the eluate to waste or to one or more collection vials in fraction collector 190 (¶[0061]).
Regarding Claim 16, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 3. Claim 16 does not add any new equipment element or functional relationship beyond Claim 13; it merely repeats that the process of Claim 3 is carried out using the same preparative RP-HPLC column, downstream back-pressure valve, and intermediate pressure indicator already made obvious in Claim 13, and such mere repetition of the same arrangement without any new or unexpected result does not confer patentable significance (In re Harza, 274 F.2d 669 (CCPA 1960)).
Claims 5-7, and 20-22 are rejected under 35 U.S.C. 103 as being unpatentable over SCHLAKE in view of PRC handbook and CUI, as applied to claim 4 above, and further in view of BROWN (US20180110947A1).
Regarding Claims 5–6, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 4. However, modified SCHLAKE does not explicitly disclose “wherein the refrigerant is selected from a haloalkane refrigerant and a hydrocarbon refrigerant,” nor “wherein the refrigerant is a haloalkane refrigerant.”
BROWN discloses methods and systems for capturing and recycling halocarbons, particularly volatile anaesthetic agents used in medical environments (¶[0001]).
A halocarbon is an organic molecule containing at least one carbon atom covalently bound to one or more halogen atoms, and halocarbons are used in solvents, pesticides, refrigerants, fire-resistant oils, elastomers, adhesives, sealants, insulating coatings, plastics, and anaesthetics (¶[0002]).
Volatile anaesthetic agents include halogenated fluorocarbons such as halothane, isoflurane, sevoflurane, and desflurane, which are chlorofluorocarbons or hydrofluorocarbons containing chlorine, bromine, or fluorine groups and are classified as halocarbons (¶¶[0017]–[0019]).
Halocarbon-containing mixtures are separated using a supercritical fluid mobile phase in an elution-type separation system. The process includes purifying and collecting halocarbons based on molecular characteristics such as polarity or molecular weight. Separation may be performed by chromatography, and collected fractions are monitored and processed using a controller. Following depressurization, purified halocarbon fractions are collected from the gaseous phase using temperature-controlled cyclonic collectors (¶¶[0054]–[0056]).
BROWN confirms that halocarbon-containing mixtures may be separated by chromatography and collected using CO₂-based separation conditions, and that the halocarbons may include chlorofluorocarbons or hydrofluorocarbons (¶¶[0054]–[0059]). In view of modified SCHLAKE’s pressure-controlled chromatographic separation of liquefied CO₂-containing material, a person skilled in the art would have applied the process to haloalkane refrigerant-containing mixtures with predictable results, since such mixtures were known target materials for CO₂-based chromatographic separation.
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 apply the haloalkane refrigerant-containing mixture, as disclosed by BROWN, to the pressure-controlled chromatographic separation process by modified SCHLAKE.
Regarding Claim 7, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 6. BROWN confirms that halocarbon-containing mixtures may be separated by chromatography using CO₂-based separation conditions, and that the halocarbons may include chlorofluorocarbons or hydrofluorocarbons (¶¶[0054]–[0059]).
Regarding the composition of the recited refrigerant blends, the listed R-series refrigerants are standard commercially available fluorinated refrigerant mixtures having fixed component weight percentages. Selecting one of those standard blend compositions merely identifies the known material being separated and does not change the underlying pressure-controlled chromatographic separation process. Applying the process to such known refrigerant blends would have produced predictable separation of known halocarbon-containing target materials by chromatography.
Regarding Claim 19, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 5.
SCHLAKE discloses a chromatographic system for analytical, semi-preparative, and preparative chromatography in which chromatography column 152 contains a stationary phase (¶¶[0014], [0048]).
Flow of the liquid mobile phase eluate from chromatography column 152 passes through detector 160 and pressure sensor 161 that measures the outlet pressure, and then continues to back pressure regulator 170 positioned downstream of the chromatography vessel to maintain the upstream process pressure P₂ during elution (¶¶[0056]–[0057]).
The downstream back-pressure valve and pressure indicator arrangement is not specific to a particular type of HPLC and remains applicable to RP-HPLC, since controlling and monitoring column pressure is a known operation during chromatographic separation.
Regarding Claim 20, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 5. Claim 20 recites the same limitation as Claim 12 and is rejected for the same reasons. Such repetition of the same condition in a different dependency chain, without any new process step, operating condition, or unexpected result, does not confer patentable significance (In re Harza, 274 F.2d 669 (CCPA 1960)).
Regarding Claim 21, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 5. Claim 21 recites the same limitation as Claim 15 and is rejected for the same reasons. Such repetition of the same recovery step in a different dependency chain, without any new process step, functional relationship, or unexpected result, does not confer patentable significance (In re Harza, 274 F.2d 669 (CCPA 1960)).
Regarding Claim 22, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 5. Claim 22 recites the same limitation as Claim 19 and is rejected for the same reasons. Such repetition of the same equipment arrangement in a different dependency chain, without any new equipment element, functional relationship, or unexpected result, does not confer patentable significance (In re Harza, 274 F.2d 669 (CCPA 1960)).
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over SCHLAKE in view of PRC handbook and CUI, as applied to claim 4 above, and further in view of BROWN, as applied to claim 3 above, and further in view of BROWN
Regarding Claim 15, modified SCHLAKE makes obvious a process for separating a liquefied gas sample of Claim 3. However, modified SCHLAKE does not explicitly disclose “a step (c) wherein the mobile phase is recovered.”
BROWN discloses methods and systems for capturing and recycling halocarbons, particularly volatile anaesthetic agents used in medical environments (¶[0001]).
After passing through chromatography column 210, separated volatile anaesthetic agents 12 and CO₂ are released from their supercritical state. The anaesthetic agents 12 are collected in cyclonic collection vessel 212, and the gaseous CO₂ is re-compressed for re-use (¶¶[0139], [0144]).
Gaseous CO₂ 207 flows into recompression pump 214, is pumped into recompression condenser 216, converted into liquid CO₂ 201, and stored in CO₂ reservoir 204 or liquid CO₂ tank 202 (¶[0145]).
In another embodiment, after staged depressurisation and fractionation, gaseous CO₂ is released via vent 660 or may be recompressed for future use (¶[0169]).
The CO₂ recovery loop disclosed by BROWN avoids continuous consumption and discharge of the CO₂ working fluid by recompressing, condensing, and storing the gaseous CO₂ for reuse (¶¶[0144]–[0145], [0169]). In view of modified SCHLAKE’s pressure-controlled chromatographic separation process using a CO₂-containing mobile phase, a person skilled in the art would have recovered the CO₂ mobile phase after separation, since recompression and reuse of CO₂ was a known solvent-recovery operation that predictably reduces CO₂ loss during preparative chromatographic processing.
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 CO₂ mobile-phase recovery loop, as disclosed by BROWN, into the pressure-controlled chromatographic separation process by modified SCHLAKE.
Response to Arguments
Applicant’s arguments, see Remarks filed February 17, 2026, with respect to the rejection of claims 3–22 under 35 U.S.C. § 103 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, new grounds of rejection are made in view of SCHLAKE, RPC Handbook, CUI, and BROWN.
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
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