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 .
Final Rejection
Claims 1, 3-5 and 7-20 pending. Claim 1 is independent. Claims 1, 3 and 7 are amended in the response filed 7/29/2026.
Response to Amendment
The rejection of claims 1, 3-5, 7-14, 16-20 under 35 U.S.C. 103 as being unpatentable over Sim et al. “Encapsulated biochar-based sustained release fertilizer for precision agriculture: A review - ScienceDirect in view of Shao et al. (2021) The formation of 5-hydroxymethylfurfural and hydrochar during the valorization of biomass using a microwave hydrothermal method - ScienceDirect and Shao et al. (2019) Hydrochar derived from green waste by microwave hydrothermal carbonization is maintained.
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Sim et al. “Encapsulated biochar-based sustained release fertilizer for precision agriculture: A review - ScienceDirect in view of Shao et al. (2021) The formation of 5-hydroxymethylfurfural and hydrochar during the valorization of biomass using a microwave hydrothermal method - ScienceDirect and Shao et al. (2019) Hydrochar derived from green waste by microwave hydrothermal carbonization and further in view of Kambo et al. A_comparative_review_of_biochar_and_hydrochar_in_t.pdf Renewable and Sustainable Energy Reviews 45 (2015) 359–378 is maintained.
Response to Arguments
Applicant's arguments filed July 29, 2026 have been fully considered but they are not persuasive. Applicant’s urge that Sim et al. do no teach a hydrochar, hydroxymethylfurfural (HMF) and a crosslinker as required by the amended claim 1.
In response to Applicant’s arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
Sim et al. is pertinent to the claim 1 as amended to include the crosslinker see section 2.5 of Sim et al. teach mixing with N.N methylene bisacrylamide (MBA) crosslinker (see section 2.5 and the abbreviations in the Introduction). See also table 2, MBA and APS were added into the mixture, polymerization was performed by using microwave irradiation. Arguments that Sim et al. teach different crosslinkers from that which is claimed is not persuasive because Sim et al. teach the N.N methylene bisacrylamide (MBA) crosslinker required by claim 7 and claim 1 is not limited by any specific crosslinker. Section 2.3 discloses 2 different crosslinking agents, namely ethylenglycol dimethacrylate and the claimed N,N′-Methylenebisacrylamide (MBA). Thus, one of ordinary skill reading Sim et al. is guided to a composition of hydrochar and crosslinker however, Sim et al. alone do not specifically teach wherein the hydrochar comprises microwave irradiated biomass and thus, its teaching is properly combined with Shao et al. (2021) teaching the formation of 5-hydroxymethylfurfural (HMF) and hydrochar during the valorization of biomass using a microwave hydrothermal method. See page 7, the example under the 5. Conclusions and fig 1 and the title explaining that hydrochar is from microwave-irradiated biomass.
As Shao et al. (2021) does not specifically teach incorporation into soil or any composition, the combination with Shao et al. (2019) establishes that one of ordinary skill understands that hydrochar is the major product from hydrothermal carbonization and has a higher carbon content and calorific value than the feedstock, hence hydrochar is useful as a fuel source, soil amendment, carbon-based catalyst, or adsorbent. Accordingly, the claim amendments are addressed below.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 3-5, 7-14, 16-20 are rejected under 35 U.S.C. 103 as being unpatentable over Sim et al. “Encapsulated biochar-based sustained release fertilizer for precision agriculture: A review - ScienceDirect in view of Shao et al. (2021) The formation of 5-hydroxymethylfurfural and hydrochar during the valorization of biomass using a microwave hydrothermal method - ScienceDirect and Shao et al. (2019) Hydrochar derived from green waste by microwave hydrothermal carbonization.
With respect to claim 1 Sim et al. teach a fertilizer composition comprising hydrochar on page 5 table 1, copied herein:
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Sim et al. teach in section 2.5 on page 6, that microwave irradiation is a commonly known polymerization method that can be utilized to synthesize the superabsorbent hydrogel-based fertilizer.
With respect to the crosslinker of claim 1, Sim et al. Section 2.3 discloses 2 different crosslinking agents, namely ethylenglycol dimethacrylate and the claimed N,N′-Methylenebisacrylamide (MBA) thus a hydrochar with a crosslinker does not provide a contribution over the art. See also table 2, MBA was added where polymerization was performed by using microwave irradiation.
However, Sim et al. do not exemplify a composition comprising a hydrochar, HMF, and crosslinker wherein the hydrochar comprises microwave irradiated biomass as required by claim 1.
In the analogous hydrochar art, Shao et al. teach the formation of 5-hydroxymethylfurfural (HMF) and hydrochar during the valorization of biomass using a microwave hydrothermal method. See page 7, the example under the 5. Conclusions and fig 1 and the title. Thus, Shao et al. (2021) teach the claim 1 hydrochar from microwave-irradiated biomass, but do not specifically teach its incorporation into soil or any composition.
In the analogous art of hydrochar derivation from green biomass waste via microwave hydrothermal carbonization, Shao et al. (2019) teach the hydrochar is the major product from hydrothermal carbonization and has a higher carbon content and calorific value than the feedstock, hence hydrochar is useful as a fuel source, soil amendment, carbon-based catalyst, or adsorbent.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to arrive at the claimed composition comprising hydrochar comprising microwave irradiated biomass because Sim et al. teach a fertilizer composition comprising hydrochar in general and Shao et al. (2021) illustrate by example hydrochar from microwave-irradiated biomass as required by claim 1 and Shao et al. (2019) guide one of ordinary skill to the claim 1 composition comprising hydrochar as soil amendments. Thus, one of ordinary skill understands that the hydrochar in the fertilizer of Sim et al. and reasonably come from the microwave irradiated biomass as taught by the Shao et al. references 2021 teaching the process and 2019 teaching the inclusion as soil amendments. One of ordinary skill is motivated to combine the teachings of Sim et al. with that of Shao et al. 2021 and Shao et al. 2019 because all are in the analogous field of hydrochar from microwave irradiation.
Shao et al. (2021) describe 5-Hydroxymethylfurfural (HMF) as evidently playing the most important role in hydrochar formation because of the dehydration of HMF. See Shao et al. (2021) Figure 1 on page 2 and the 2nd to last line in the left column. See page 2 last 10 lines of the left column of Shao et al.(2021) teaching that formation of hydrochar from fructose is formed by the dehydration of HMF. Examiner notes Applicant’s specification [0046] and [0076] describe “The methods deposit hydroxymethylfurfural (HMF), an organic compound formed by the dehydration of food waste with high heating values to the produced hydrochar, which further increases the hydrochar porosity and augment the overall energy density of hydrochar. It is the Examiner’s position that the dehydration of fructose and biomass yields the same hydrochar formed by the dehydration of HMF encompassing the Applicant’s specification [0076]. Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to arrive at the claimed composition comprising hydrochar, comprising microwave irradiated biomass HMF and crosslinker as required by claim 1 and further comprising HMF deposited on the hydrochar as required by claim 3, because Sim et al. teach a composition comprising hydrochar in general and Shao et al. (2021) teach hydrochar formation by the dehydration of HMF and Examiner notes that Applicant’s specification discloses the deposit of HMF in [0076] via a dehydration as is also explained by the MHTC process disclosed by Shao (2021).
With respect to the initiator of claims 4-5 and the crosslinker of claim 7, Sim et al. teach mixing with ammonium persulfate (APS) potassium persulfate (KPS) initiators with N.N methylene bisacrylamide (MBA) crosslinker (see section 2.5 and the abbreviations in the Introduction) teach mixing with the claimed initiators and crosslinker to form the hydrogel. See also table 2, MBA and APS were added into the mixture, polymerization was performed by using microwave irradiation. Section 2.3 discloses 2 different crosslinking agents, namely ethylenglycol dimethacrylate and the claimed N,N′-Methylenebisacrylamide (MBA).
With respect to the solvent of claims 8-9, see Sim et al. pages 5,7 Tables 1 and 2 where the fertilizer with the hydrochar is with urea.
With respect to the biochar of claims 10-11, see Sim et al. table 1 where the fertilizer is a urea biochar and urea hydrochar
With respect to biomass of claim 12 Sim et al. teach organic materials such as animal manure, sludge, food waste, green waste and agricultural waste can be used as the precursors for biochar production, See section 3.1 on page 7, right col.
With respect to claim 13 limitation to the biomass being microwave irradiated via microwave mediated hydrothermal carbonization Sim et al. teach microwave irradiation in general. See Table 2. And Shao et al. (2021) illustrate the claimed microwave hydrothermal method. See Fig.1.
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Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to arrive at the claim 13 biomass that is microwave irradiated by microwave mediated hydrothermal carbonization, because Sim et al. teach a fertilizer composition derived from food waste that is microwave irradiated to form a hydrochar composition in general and Shao et al. (2021) illustrate by example hydrochar from microwave-irradiated biomass and Shao et al. (2019) guide one of ordinary skill to that hydrochar utility as soil amendments. Thus, one of ordinary skill understands that the hydrochar in the fertilizer of Sim et al. can reasonably come from the microwave irradiated biomass as taught by Shao et al. and further teaching its inclusion as soil amendments.
Claim 14 method of irradiating the biomass with microwaves under an inert atmosphere at conditions effective to yield the hydrochar is shown in Shao et al. (2021) Fig. 2, page 3, right column in purple triangles and copied herein below:
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Claim 16 method to irradiating with microwaves having a frequency, an energy, or a combination thereof, sufficient to heat the biomass to a temperature sufficient to yield the hydrochar is shown by Fig. 1 and on page 3, section 2.2 teaching obtaining the hydrochar.
Claims 17-18 limitation to wherein the method is performed at a temperature of
from 150°C to 250°C at a pressure of 6 MPa and wherein the irradiation step lasts from 5 minutes to 2 hours is taught by Shao et al. Figure 1 highlighted in red under the image of the microwave.
With respect to claim 19, Shao et al. (2021) do not teach limitation to wherein generating the composition has an activation energy of from 150 MJ/kg to 255 MJ/kg as required by claim 19. However, Shao et al. (2021) teach by example a microwave hydrothermal method with the same temperature, pressure and time as in Applicants specification US20240336842 which [0052] generates the claimed activation energy. Thus, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to arrive at the claimed activation energy of from 150 MJ/kg to 255 MJ/kg as required by claim 19 because Shao et al. (2021) Figure 1, exemplifies the same microwave hydrothermal method with the same temperature, pressure and time of irradiating the analogous biomass with the same microwave hydrothermal method, thus, one of ordinary skill would reasonably expect the same activation energy property as claimed.
With respect to claim 20, the table 1 and 2 of Sim et al. illustrate hydrochar based compositions for use as fertilizers to improve the quality of soil.
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Sim et al. “Encapsulated biochar-based sustained release fertilizer for precision agriculture: A review - ScienceDirect in view of Shao et al. (2021) The formation of 5-hydroxymethylfurfural and hydrochar during the valorization of biomass using a microwave hydrothermal method - ScienceDirect and Shao et al. (2019) Hydrochar derived from green waste by microwave hydrothermal carbonization.as applied to claims 1, 3-5, 7-14, 16-20 above and further in view of Kambo et al. A_comparative_review_of_biochar_and_hydrochar_in_t.pdf Renewable and Sustainable Energy Reviews 45 (2015) 359–378.
Sim et al., Shao et al. (2019) and Shao et al. (2021) is relied upon for its explicit illustration of 5-HMF and hydrochar from biomass using a microwave hydrothermal method however, they do not teach the claim 15 method recirculation of a liquid during the irradiation step. Examiner notes that Shao et al.(2021) Fig 1 on page 2 does not use the term recirculation.
In the analogous art of hydrothermal carbonization, Kambo et al. teach obvious and important advantages associated with the recirculation of hydrothermal carbonization HTC process water include (i) Reduction in the wastewater that would also reduce the wastewater treatment cost associated with HTC plant, (ii) recirculation of the process water has been suggested as the most efficient method of heat recovery and can reduce the external heat consumption by ten-folds, (iii) the formation of acetic acid in the process water may further catalyze the process during recirculation and therefore can simultaneously reduce the pressure and temperature requirements, (iv) the degraded sugar compounds from the biomass polymers present in the HTC process water might deposit in the porous structure of hydrochar, which may further augment the overall energy density of solid, and (v) the HTC process water can be used for the anaerobic digestion of certain types of biomass. See pg. 364, right col. section 2.2.4.2.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to arrive at the claimed recirculation of a liquid during the irradiation step as required by claim 15 because Sim et al. teach a hydrochar composition in general and Shao et al. (2021 and 2019) hydrochar for soil amendments from biomass using a microwave hydrothermal method in general and Kambo et al. guide one of ordinary skill to obvious and important advantages associated with the recirculation of hydrothermal carbonization HTC process water as the most efficient method of heat recovery and can reduce the external heat consumption by ten-folds. One of ordinary skill is motivated to combine the teachings because all are in the analogous hydrochar art.
Conclusion
THIS ACTION IS MADE FINAL. 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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/PREETI KUMAR/Examiner, Art Unit 1761
/ANGELA C BROWN-PETTIGREW/Supervisory Patent Examiner, Art Unit 1761
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