Composition of foliar fertilizer based on by-product of hydrothermal carbonization of sugarcane bagasse and vinasse and method of application of said composition

Description

1 / 16 COMPOSITION OF FOLIAR FERTILIZER BASED ON BY-PRODUCT OF HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE AND METHOD OF APPLICATION OF SAID COMPOSITION BRIEF DESCRIPTION

[001] This patent application relates to a “FOLIAR FERTILIZER COMPOSITION BASED ON BY-PRODUCTS OF THE HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE AND METHOD OF APPLICATION OF SAID COMPOSITION”, which refers to a foliar fertilizer composition and its method of application to plants. Said composition utilizes process water, resulting from the hydrothermal carbonization of sugarcane bagasse and vinasse, in different concentrations of total organic carbon, combined with selected mineral nutrients. The invention further describes a foliar application method that includes the application method, the quantities to be applied, the required volume, the distance from the plant, and the interval between each application. FIELD OF APPLICATION

[002] The present invention belongs to the chemistry section, to the field of organic fertilizers, more specifically, to the field of fertilizers manufactured with distillery waste, molasses, vinasse, sugar mill waste, waste or similar residues; as it refers to a foliar fertilizer composition that employs process water resulting from the hydrothermal carbonization of sugarcane bagasse and vinasse, as well as to its method of application to plants. CONVINCING

[003] Sugarcane is a biomass widely produced by the sugar and ethanol industry in Brazil. The 2023 harvest was responsible for the production of 560.54 million tons of this resource, most of which is processed for the production of sugar and ethanol (Sugarcane Industry Union and Sugarcane and Bioenergy Observatory— Fortnightly monitoring of the harvest in the Center-South region).

[004] The significant production of the sugar and ethanol industry leads to a large production of residual by-products, among them sugarcane bagasse and vinasse. A Petition 870250012542, dated 02 / 14 / 2025, page 10 / 52 2 / 16 Vinasse originates from the ethanol distillation process, generating approximately 10 to 14 liters of vinasse for each liter of ethanol produced. The main destination of this residue is the fertigation of sugarcane fields. Bagasse, another important byproduct, has an estimated production of about 280 kg of bagasse for each ton of sugarcane processed and is used in energy cogeneration (PUGLIESE, L., LOURENCETTI, C, RIBEIRO, ML. Environmental impacts on Brazilian ethanol production: a brief discussion from the field to the industry. Revista Brasileira Multidisciplinar, V.20, N.1, P. 142-165, 2017).

[005] Although these by-products have utility, they are produced in large volumes, which generates the need to consider other uses and applications capable of adding value to them. In this context, the search for alternatives that promote the sustainable use of biomass is fundamental, both for the economy and for the conservation of natural resources and the preservation of future generations.

[006] One of the alternative applications of these by-products is their subjection to hydrothermal carbonization processes for the production of fertilizers. In these processes, sugarcane bagasse and vinasse result in the formation of a solid product, known as hydrothermal charcoal, a liquid designated as process water, and a gaseous state.

[007] The present invention enables the use of process water as a fundamental component of the composition of foliar fertilizer and proposes a method for applying this composition, which has characteristics that favor plant development, such as a high concentration of carbon and the presence of phosphorus, potassium, calcium, magnesium and nitrate (FREGOLENTE, LG, MIGUEL, TBAR, DE CASTRO MIGUEL, E. et al. Evaluation of the toxicity of process water from the hydrothermal carbonization of sugarcane industry by-products. Environ Sci Pollut, V.26, P. 27579-27589, 2019). The composition also includes phenolic compounds, ketones, alcohols, carboxylic acids and aldehydes, from the biomass degradation process, as well as nitrogen compounds, furans and sulfur (LARANJA, 2018). Petition 870250012542, dated 02 / 14 / 2025, page 11 / 52 3 / 16

[008] Although hydrothermal carbonization processes of biomass and the application of the products obtained in agriculture are widely known, the need to develop new fertilizers within the context of a circular economy is growing, as is the proper disposal of process water.

[009] In this context, the present invention is inserted, which aims to contribute to sustainable development by providing a foliar fertilizer composition that uses process water from the hydrothermal carbonization of sugarcane bagasse and vinasse as a starting material, which contributes both to the economy and to the conservation of natural resources, in addition to providing essential nutrients for plant development in a sustainable and low-cost manner.

[010] The proposed foliar fertilizer composition consists of an organomineral fertilizer that provides organic carbon and nitrogen to plants, improves root development, and increases the rate of photosynthesis, being able to significantly increase plant growth in shoot height and root length. In trials conducted using the foliar fertilizer on corn and tomato crops, high photosynthetic efficiency was observed with an increase in chlorophyll, which demonstrates the efficiency of using process water obtained through the hydrothermal carbonization of sugarcane bagasse with vinasse as a source of organic matter. In addition to the good results in relation to crop cultivation, the product also adds value to the technical field by enabling the reuse of by-products from sugar and ethanol plants and by contributing to better management of the waste generated by them. BACKGROUND OF THE INVENTION

[011] In the current state of the art, there are some documents that refer to fertilizer compositions produced from agro-industrial biomass waste, through processes that employ hydrothermal carbonization. However, given that there is a growing demand for the development of new fertilizers within the context of a circular economy and that, in general, current fertilizers obtained by hydrothermal carbonization are not obtained from process water but from solid biomass, the present invention represents a major technological advance that Petition 870250012542, dated 02 / 14 / 2025, page 12 / 52 4 / 16 solves problems related to the proper disposal of this waste, process water, enabling the transformation of this environmental liability into an asset.

[012] In this sense, the use of process water as a raw material in a foliar fertilizer composition is a differentiating factor of the present invention, since currently only hydrothermal carbon obtained from the hydrothermal carbonization process has applications. In addition to the composition of a foliar fertilizer that meets current demands, the present invention also provides a method for applying the claimed foliar fertilizer, which was tested in tomato and corn crops, with spray application at novel concentrations of total organic carbon in organic matter and with added salts.

[013] The prior art BR102015003018-5, entitled Process for converting vinasse into carbon- and nutrient-rich solid material and clarified water for reuse, refers to a process for obtaining a carbon- and nutrient-rich ecomaterial and clarified water for reuse from vinasse, which consists of the hydrothermal carbonization of vinasse, with control of the variables temperature, reaction time and acidity of the reaction medium, transforming the organic matter present in the medium into a carbon- and nutrient-rich solid material with potential use as general-purpose fertilizers and controlled-release fertilizers, for fertilizing various agricultural crops, and clarified water with potential reuse in the industrial process.

[014] The focus of the prior art is the process of obtaining a product rich in carbon and nutrients via hydrothermal carbonization of vinasse. The document describes the best process conditions (temperature, reaction time, and acidity of the reaction medium) to obtain said product. As in the present invention, the product obtained is also used as a fertilizer for agricultural crops. However, the prior art uses the solid part of the product obtained from the hydrothermal carbonization process, while in the present invention the fertilizer formulation is based on the liquid part, designated as process water. Therefore, although the document does not focus on or clearly describe the composition of the fertilizer, this difference is sufficient to distinguish the present invention from the prior art, demonstrating its contribution to the technical field. Petition 870250012542, dated 02 / 14 / 2025, page 13 / 52 5 / 16

[015] The prior art BR102016002221-5, entitled Process for the production of organomineral fertilizer from the hydrothermal carbonization of vinasse and sugarcane bagasse and the product obtained, describes a process for the production of organomineral fertilizer with water retention capacity from the hydrothermal carbonization (HCT) of vinasse and sugarcane bagasse, in which an acid catalyst, preferably phosphoric acid, is employed in a hydrothermal carbonization process, adding value to these residues, allowing them to be applied within the production cycle itself, reducing costs with transportation, fertilizers, chemical treatments, among others.

[016] The document employs a hydrothermal carbonization process that utilizes vinasse and sugarcane bagasse, in which an acid catalyst is used to obtain a product to be used as an organomineral fertilizer with water retention capacity. The process, as described in the first prior invention, also utilizes the solid part of the product obtained from the hydrothermal carbonization process, whereas in the present invention the fertilizer formulation is based on process water. Therefore, the fertilizer compositions are also different from each other.

[017] The prior art BR102020012903-1, entitled Alternative liquid fertilizer based on tannery sludge associated with cachaça vinasse for foliar fertilization of coffee, refers to the development of a liquid fertilizer for fertilizing coffee seedlings, with the aim of improving the growth and development of the seedlings, in order to use the by-product of the tanning industry, also known as tannery sludge, and the by-product of the cachaça industry, also known as vinasse, as a basis for the formulation of a foliar fertilizer for coffee cultivation.

[018] The document differs from the present invention because it involves a direct mixture of tannery sludge and vinasse diluted in water, with a specific defined use, namely the production of conilon coffee seedlings. In the present invention, the formulation uses process water, derived from the hydrothermal carbonization of sugarcane bagasse and vinasse, with added essential carbon-based minerals for the development of tomato and corn plants. Therefore, the fertilizer compositions are also different from each other. Petition 870250012542, dated 02 / 14 / 2025, page 14 / 52 6 / 16

[019] De Souza and collaborators (2021), in a publication in the Proceedings of the XXXIII Scientific Initiation Congress of Unesp, entitled Study of process water from the hydrothermal carbonization of sugarcane bagasse for tomato growth, reported the evaluation of the effect of applying process water from the hydrothermal carbonization of sugarcane bagasse and vinasse as a source of chelating organic matter in foliar fertilizer in tomato cultivation in argisol.

[020] Although the prior art deals with the same subject as the present invention, the abstract presented at the congress does not describe in detail, in a way that would allow the reproduction of the composition of the foliar fertilizer or its method of application to plants, as claimed in the present invention. Thus, the prior art does not anticipate the patentability requirements of the composition, since it only indicates the research objectives, the variables evaluated and the conclusions.

[021] Priorities are still present in the current state of the art. CN107082685A, entitled “A type of method for preparing low-release hydrothermal carbon-based nitrogen fertilizer by hydrothermal carbonization process”; CN108440076A, entitled “The method for preparing liquid fertilizer using sludge hydrothermal carbonization waste liquid”, which refers to the preparation of liquid fertilizer using municipal sludge and digested sludge as raw material for the hydrothermal carbonization process employed in the process;CN105900984A, entitled "Method for preparing pesticide by using biomass hydrothermal carbonization liquid phase and preparing organic fertilizers by using solid phase," which provides a method for preparing pesticide and organic fertilizer employing hydrothermal carbonization using citrus pulp as raw material, with the reaction product separated by filtration or centrifugation, where the liquid phase, rich in furfural with strong bactericidal power, phenol and its derivatives, is extracted with ethyl acetate to prepare a pesticide, and the solid phase, which has most of the nutrients from the biomass, is dried to prepare an organic fertilizer; CN106966766A, entitled "A kind of method that hydrothermal carbonization processing bean dregs black mud prepares fertilizer," which... Petition 870250012542, dated 02 / 14 / 2025, page 15 / 52 7 / 16 refers to the method of preparing fertilizer from black mud from bean residue by hydrothermal carbonization with the addition of two acid catalysts in two stages; in the first stage, acetic acid is added before insertion into the reactor, and then concentrated sulfuric acid is added during the reaction inside the reactor; and CN111410590A, entitled 'Fertilizer applied by combining wheat straw biochar with straw and application method', which describes the development of fertilizer applied by combining wheat straw biomass biochar by hydrothermal carbonization.

[022] Based on the prior art recovered in the current state of the art, it is noted that the present invention solves a technical problem related to the use of process water from the hydrothermal carbonization of sugarcane bagasse and vinasse, byproducts of the sugar and alcohol industry, presenting advantageous results, even considering the combination of the teachings of the cited documents. Furthermore, a person skilled in the art would not arrive at the present invention from mere modifications of the techniques presented in the state of the art, which corroborates the inventiveness of the claimed matter, which refers to a foliar fertilizer composition that uses process water resulting from the hydrothermal carbonization of sugarcane bagasse and vinasse, with different concentrations of total organic carbon, combined with selected mineral nutrients; and to its method of application. OBJECTIVE OF THE INVENTION

[023] The present invention aims to provide a foliar fertilizer composition that uses process water, derived from the hydrothermal carbonization of sugarcane bagasse and vinasse, as a starting material, capable of providing essential nutrients to plants in a sustainable and low-cost manner, in addition to promoting savings and conservation of natural resources. OF THE INVENTION

[024] The present invention relates to a carbon-based foliar fertilizer composition, obtained from a mixture of process water (1:20 m / m), derived from the hydrothermal carbonization of sugarcane bagasse and vinasse, in the presence of sulfuric acid (1-4%). ​​The foliar fertilizer composition also comprises the minerals Ca (0.1-0.6%), Mg (0.01-0.04%), B (0.01-0.04%), Cu (0.01-0.05%), Mn (0.1-0.5%) and Zn. Petition 870250012542, dated 02 / 14 / 2025, page 16 / 52 8 / 16 (0.5-1%) added in order to provide essential nutrients for plant development.

[025] The invention also relates to the ideal foliar application method, including the application method, the number of applications, the required volume, the distance and interval of each application, and teaches that the dosage of fertilizer in tomato and corn cultivars should be administered through different treatments with concentrations ranging from 0-500 mg C L-1 of total organic carbon. ADVANTAGES OF THE INVENTION

[026] The present invention has the following main advantages: ✓ To provide a foliar fertilizer composition that uses process water from the hydrothermal carbonization of sugarcane bagasse and vinasse as a starting material; ✓ To provide a foliar fertilizer composition that supplies organic carbon and nitrogen to plants, improves root development and increases the rate of photosynthesis, being able to significantly increase plant growth in shoot height and root length; ✓ To provide a foliar fertilizer composition that follows the principles of circular economy, in accordance with best practices for sustainable development and the conservation of natural resources. DESCRIPTION OF THE FIGURES

[027] In order to facilitate understanding of the present invention, reference will be made to the following figures: ✓ Figure 1A presents graphs comparing the growth between the control and treatments after the application of foliar fertilizers 35 days after tomato planting. These graphs show: T1: Control: treatment with foliar application of 0 mg L-1C; T2: Treatment with foliar application at a rate of 50 mg L-1C; T3: Treatment with foliar application in the range of 100 mg L-1C; T4: Treatment with foliar application at a rate of 500 mg L-1C; T5: Treatment with only the nutrients diluted in water; Petition 870250012542, dated 02 / 14 / 2025, page 17 / 52 9 / 16 ✓ Figure 1B shows a comparison of growth between the control and treatments after the application of foliar fertilizers 35 days after corn planting. This is: M1: Control: treatment with foliar application in the range of 0 mg C L-1; M2: Treatment with foliar application in the range of 50 mg C L-1; M3: Treatment with foliar application in the range of 100 mg C L-1; M4: Treatment with foliar application at a rate of 500 mg C L-1 and M5: Treatment with only the nutrients diluted in water; ✓ Figure 2A shows the dry mass of the aerial parts and roots of tomato plants 35 days after planting; ✓ Figure 2B shows the dry mass of the aerial parts and roots of corn 35 days after planting; ✓ Figure 3A shows the chlorophyll graph from the corn plant growth experiment after foliar fertilizer applications; ✓ Figure 4A shows the scanning electron microscopy image of tomato leaves T1 (treatment with 0 mg L-1C); ✓ Figure 4B of sheet T2 (treatment with 50 mg C L-1); ✓ Figure 4C of leaf T3 (treatment with 100 mg C L-1); ✓ Figure 4D of leaf T4 (treatment with 500 mg C L-1); ✓ Figure 4E of leaf T5 (treatment with only nutrients diluted in water); ✓ Figure 5A shows the scanning electron microscopy image of the leaves of corn M1 (treatment with 0 mg C L-1); ✓ Figure 5B of leaf M2 (treatment with 50 mg C L-1); ✓ Figure 5C of leaf M3 (treatment with 100 mg C L-1); ✓ Figure 5D of leaf M4 (treatment with 500 mg C L-1); ✓ Figure 5E of leaf M5 (treatment with only nutrients diluted in water); ✓ Figure 6 shows images of the tomato at the end of the growth experiment, being: A (treatment with 0 mg C L-1); B (treatment with 50 mg C L-1); Petition 870250012542, dated 02 / 14 / 2025, page 18 / 52 10 / 16 °C (treatment with 100 mg C L-1); D (treatment with 500 mg C L-1) and; E (treatment with only the nutrients diluted in water). DETAILED DESCRIPTION OF THE INVENTION

[028] The present invention relates to a foliar fertilizer composition employing process water resulting from the hydrothermal carbonization of a mixture of sugarcane bagasse and vinasse (1:20 m / m), in the presence of sulfuric acid (1-4%), combined with the mineral nutrients Ca (0.1-0.6%), Mg (0.01-0.04%), B (0.01-0.04%), Cu (0.01-0.05%), Mn (0.1-0.5%) and Zn (0.5-1%). The composition has a total organic carbon concentration of 20-40 g C L-1 as the base carbon, comprising a dilution in water with total organic carbon concentrations in the range of 50 to 500 mg C L-1.

[029] The method of applying the composition consists of applying two doses, by spraying approximately 500 μL per plant, with an interval of 10 days between the two applications and at a distance of 30 cm from the plant in the concentration range of 50 to 500 mg C L-1.

[030] From the application of the composition at a concentration of 100 mg C L-1, in experiments on tomato crops, an increase of 20% in shoot height, 9% in root height, 14% in total plant length and 77% in total dry mass was observed.

[031] From the application of the composition at a concentration of 500 mg C L-1, in experiments on corn crops, an increase of 8% in shoot height, 29% in total dry mass and 57% in total chlorophyll content was observed.

[032] The experiments, presented later, demonstrated that the composition did not cause modification in the cell wall and structure of tomato and corn plants, nor anatomical ruptures with the application of foliar fertilizer in adequate concentrations of total organic carbon in the process water.

[033] To obtain the process water used in the present invention, a mixture of bagasse and vinasse from sugarcane, in a biomass ratio of 1:20 (m / m), undergoes a hydrothermal carbonization (HTC) process in the presence of H2SO4, Petition 870250012542, dated 02 / 14 / 2025, p. 19 / 52 11 / 16 in a proportion of 1-4% v / v of the mixture, in a Teflon reactor lined with stainless steel, at a temperature of 100-250°C, for a period of 13 hours. At the end of the reaction time, the reactor was subjected to an ice bath until it reached room temperature. Then, process water (PW), which is the liquid fraction of the mixture and component used in the present invention, was separated from the hydrothermal coal (HC) by vacuum filtration.

[034] The preparation of the foliar fertilizer composition began with process water containing a total organic carbon (TOC) concentration of 39.88 g C L-1. From this base, several dilutions were made to obtain TOC concentrations ranging from 50 mg C L-1 to 500 mg C L-1, and the nutrients were added in their respective proportions (m / v): Ca (0.1-0.6%), Mg (0.01-0.04%), B (0.01-0.04%), Cu (0.01-0.05%), Mn (0.1-0.5%), and Zn (0.5-1%). For analysis purposes, a condition with only process water and another with only distilled water were included.

[035] Foliar fertilizer application trials.

[036] Application trials were conducted with two different crops: tomato (Solanum lycopersicum, Solanaceae) and corn (Zea mays, Poaceae), and began with planting preparation. Each treatment was conducted in five replicates, using 500 g of clay soil previously corrected with liming. In each pot, five seeds were planted at a depth of 1-2 cm. After 12 days of planting, thinning was carried out, selecting only one plant per pot to remain until the end of the experiment. The experiments were conducted in a climate chamber (TE-4002, Tecnal), maintained at 26 °C, 55% humidity and a photoperiod of 16 hours day and 8 hours night for a period of 35 days, being irrigated with distilled water as needed.

[037] The effect of foliar fertilizer on crops was evaluated after the application of two doses by spraying, at a distance of 30 cm from the plant and with an interval of 10 days between applications. For each application, a volume of approximately 500 μl was sprayed into each pot. The first application occurred after 5 days of growth and the second after 15 days of growth, in both crops. Petition 870250012542, dated 02 / 14 / 2025, page 20 / 52 12 / 16

[038] The treatments performed are described below, where: T is for tomato crop and M is for corn crop and C is the total organic carbon concentration: ✓ T1: Control: treatment with foliar application of 0 mg C L-1; ✓ T2: Treatment with foliar application of 50 mg C L-1; ✓ T3: Treatment with foliar application of 100 mg C L-1; ✓ T4: Treatment with foliar application of 500 mg C L-1; ✓ T5: Treatment with only the nutrients diluted in water; ✓ AP: Treatment with raw process water; ✓ M1 Control: treatment with foliar application of 0 mg C L-1; ✓ M2 Treatment with foliar application of 50 mg C L-1 ✓ M3 Treatment with foliar application of 100 mg C L-1; ✓ M4 Treatment with foliar application of 500 mg C L-1; ✓ M5 Treatment with only the nutrients diluted in water.

[039] The growth results at the end of the experiment are presented in Table 1 and are best visualized in Figures 1A and 1B. It can be observed that, for all parameters evaluated, such as growth measurements, dry mass, chlorophyll content, and scanning electron microscopy (SEM) analysis, treatments T2 and T3 with tomato showed superior results compared to the control and the other treatments. However, under the AP condition, with foliar application of concentrated process water, all conditions did not withstand the effect of the fertilizer. Regarding the experiment with corn, treatment M4 showed better development when compared to M1, M2, M3, and M5 for all parameters evaluated.

[040] In the AP treatment with foliar application of raw process water, all conditions were unable to withstand the effect of the fertilizer. Regarding the experiment with corn, treatment M4 showed better development when compared to M1, M2, M3 and M5 for all parameters evaluated. The measurements were performed using ImageJ software. The software processes the image and then the user uses the Straight Line option to determine a scale on the ruler.

[041] Subsequently, with the Freehand Line option, a segment is drawn in the region of interest and thus the desired length is obtained. Petition 870250012542, dated 02 / 14 / 2025, page 21 / 52 13 / 16 Treatment Number of Leaves Length (cm) Total Length (cm) Shoot Root T1 18.0 ± 2.8 23.3 ± 2.8 40.0 ± 6.6 60.3 ± 8.6 T2 21.2 ± 1.4 22.8 ± 2.3 40.3 ± 7.4 63.1 ± 8.1 T3 22.8 ± 3.0 28.1 ± 3.8 40.7 ± 8.0 68.8 ± 8.6 T4 18.2 ± 2.2 23.1 ± 3.9 36.5 ± 4.1 59.6 ± 5.2 T5 19.4 ± 1.4 21.6 ± 2.8 35.8 ± 4.3 57.4 ± 5.2 M1 4.8 ± 0.3 57.46 ± 2.5 80.8 ± 2.5 131.2 ± 4.0 M2 5.0 ± 0.0 57.7 ± 6.3 77.2±11.4 134.8 ±16.8 M3 5.0 ± 0.0 61.30 ± 3.9 73.1± 4.2 134.5 ± 5.1 M4 5.4 ± 0.5 62.5 ± 4.4 72.9±18.7 135.4 ±22.8 M5 5.0 ± 0.0 57.5 ± 7.3 77.0 ± 9.3 134.5 ± 16.3 Table 1: Average number of leaves, shoot and root length, and total length after 35 days of planting, measured using ImageJ software.

[042] The evaluation of each treatment was carried out by analyzing the dry mass of the roots and aerial parts of the set of each treatment, in an oven at a temperature of 105°C for 24h and analysis by Scanning Electron Microscopy (SEM) using the FEI Company microscope: INSPECT 50 and model Q150TES.

[043] Table 2 shows the dry mass of the shoots and roots analyzed in the experiments conducted for tomato and corn, while the graphs in Figures 2A and 2B show the behavior of the different treatments in relation to the control group. Dry mass (g) Treatment Aerial part Root Total T1 0.47 ± 0.13 0.13 ± 0.06 0.59 ± 0.18 T2 0.71 ± 0.06 0.20 ± 0.03 0.91 ± 0.08 T3 0.89 ± 0.15 0.16 ± 0.03 1.05 ± 0.18 Petition 870250012542, dated 02 / 14 / 2025, page 22 / 52 14 / 16 T4 0.52 ± 0.08 0.11 ± 0.01 0.63 ± 0.08 T5 0.51 ± 0.11 0.13 ± 0.03 0.64 ± 0.13 M1 0.39 ± 0.01 0.24 ± 0.02 0.63 ± 0.03 Table 2: Average dry mass of aerial parts and roots after 35 days of planting.

[044] Treatments with foliar application of T2 (50 mg L-1C) and T3 (100 mg L-1C) in tomato crops showed better plant development compared to the control group, both in shoot and root size and dry mass.

[045] For foliar application in corn, shoot, root and total dry mass development was better for treatment M4 (500 mg L-1C). It is evident that doses with different concentrations of total organic carbon promote inversely proportional qualitative and quantitative improvements for tomato and corn crops, with higher concentrations being better for corn and lower concentrations for tomato.

[046] Considering that, in addition to the carbon-rich process water produced from hydrothermal carbonization, added nutrients played a fundamental role in improving plant growth, since fertilizers are the main source of plant nutrients (KATHPALIA and BHATLA, chap. I., p. 37-81, 2018).

[047] With regard to plant chlorophyll, the crops used as examples of application of the foliar fertilizer of the present invention are demanding in relation to nitrogen compounds, nitrogen being of paramount importance in plant metabolism, given its direct participation in the biosynthesis of proteins and chlorophylls (ANDRADE et al., 2003).

[048] Figure 3A shows the chlorophyll content among the treatments. The 500 mg L-1C condition showed greater development and a higher chlorophyll index due to the higher concentration of nitrogen compounds present in the process water, since the presence of vinasse and sugarcane bagasse in the reaction medium during hydrothermal carbonization released the formation of nitrogen compounds. Furthermore, the increase in the classes of nitrogen compounds may be due to the greater solubilization of these compounds in the process water produced by the addition of acid to the medium. Petition 870250012542, dated 02 / 14 / 2025, page 23 / 52 15 / 16 reaction (Da SILVA, 2018). It is worth noting that determining chlorophyll content in leaves is of paramount importance, as the plant's photosynthetic activity depends on the leaf's ability to absorb light. One of the factors linked to photosynthetic efficiency, growth, and adaptability of plants is chlorophyll content.

[049] In connection with plant development and growth data, SEM analyses of tomato leaves showed a large number of multicellular tector trichomes, observed in Figure 3, mainly in treatments T2 and T3 referring to foliar application of 50 and 100 mg L-1C, except in treatments T4 (500 mg L-1C) and T5 (nutrients only), which show rare multicellular tector trichomes.

[050] While SEM images of corn leaves, shown in Figure 4, show that the presence of unicellular tector trichomes is rare in all treatments. Tector trichomes closely resemble hairs and have the function of reducing water loss through transpiration in plants living in environments with water stress.Furthermore, they can hinder the movement of insects on the leaves, provide protection against direct sunlight, and act as thermal insulation by trapping air, which demonstrates better development of foliar fertilizer under these conditions, even compared to the control.

[051] With regard to stomata, in tomato cultivation all treatments showed closed anisocytic stomata and in corn showed closed dumbbell-shaped stomata on the abaxial surface of the leaf. Stomata have the function of carrying out gas exchange between the plant and the environment. The opening and closing of the stomata are determined by factors that include light incidence, reduction of carbon dioxide levels, as well as physical stresses such as humidity and high temperature.

[052] In its abaxial epidermis, the cells of the periclinal wall were shown to be slightly sinuous and convex in shape for both cultures. This wall shape has the ability to concentrate light, that is, if there is little light the tendency of the periclinal wall is to obtain this convex shape.

[053] In addition, an increase in plant cell size was observed in treatments M3, M4 and M5 (conditions of 100 mg C L-1, 500 mg L-1C and nutrients only, Petition 870250012542, dated 02 / 14 / 2025, page 24 / 52 16 / 16 respectively). In all corn crop treatments, the plant cell walls remained with the same sinuosity in relation to the control treatment.

[054] From the above, it is clear that the use of process water as a source of organic matter for the preparation of foliar fertilizer has potential for plant growth and development, since in tomato crops, conditions T2 and T3 and corn, condition M4, were the ones that showed the best development in physical and biological aspects in the parameters of photosynthetic efficiency, growth and dry mass, and no alteration of the cell wall, evidencing that the use of process water obtained through the hydrothermal carbonization of sugarcane bagasse with vinasse as a source of organic matter in fertilizer significantly stimulates plant development. Petition 870250012542, dated 02 / 14 / 2025, page 25 / 52

Claims

1 / 2 CLAIMS 1. FOLIAR FERTILIZER COMPOSITION BASED ON BY-PRODUCT OF HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE, characterized by consisting of process water resulting from the hydrothermal carbonization of a mixture of sugarcane bagasse and vinasse (1:20 m / m), in the presence of sulfuric acid (1-4%), with a total organic carbon concentration of 20-40 g C L-1 and mineral nutrients Ca (0.1-0.6%), Mg (0.01-0.04%), B (0.01-0.04%), Cu (0.01-0.05%), Mn (0.1-0.5%) and Zn (0.5-1%), being, for use, diluted in water.

2. FOLIAR FERTILIZER COMPOSITION BASED ON BY-PRODUCT OF HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE, according to claim 1, characterized in that the process water used is the liquid portion resulting from the hydrothermal carbonization of a mixture of sugarcane bagasse and vinasse, in a proportion of 1:20 m / m, in the presence of sulfuric acid, in a proportion of 1-4% relative to the mixture, at a temperature of 100-250°C, with a reaction time of 13 hours.

3. FOLIAR FERTILIZER COMPOSITION BASED ON BY-PRODUCT OF HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE, according to claim 1, characterized by having a total organic carbon concentration of 20-40 g C L-1, as a carbon basis.

4. FOLIAR FERTILIZER COMPOSITION BASED ON BY-PRODUCT OF HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE, according to claim 1, characterized by comprising dilution in water with total organic carbon concentrations in the range of 50 to 500 mg C L-1.

5. METHOD OF APPLYING THE FOLIAR FERTILIZER COMPOSITION BASED ON A BY-PRODUCT OF THE HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE, defined in claim 1, characterized by consisting of applying two doses of the composition, by spraying Petition 870250012542, dated 02 / 14 / 2025, page 40 / 52 2 / 2 of 500 μL per plant, with an interval of 10 days between the two applications and at a distance of 30 cm from the plant in the concentration range of 50 to 500 mg C L-1.

6. METHOD OF APPLYING A FOLIAR FERTILIZER COMPOSITION BASED ON A BYPRODUCT OF THE HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE, according to claim 5, characterized by being applied at a concentration of 500 mg C L1, in maize crops.

7. METHOD OF APPLYING A FOLIAR FERTILIZER COMPOSITION BASED ON A BYPRODUCT OF THE HYDROTHERMAL CARBONIZATION OF SUGARCANE BAGASSE AND VINASSE, according to claim 5, characterized by being applied at a concentration of 100 mg C L⁻¹, in tomato crops. Petition 870250012542, dated 02 / 14 / 2025, pp. 41 / 52

Images