Description:FIELD OF THE INVENTION
The present invention relates to the field of water purification, specifically to the development of bio-ceramic nanocomposite materials for the simultaneous removal of fluoride and arsenic from contaminated groundwater in an efficient, eco-friendly, and cost-effective manner.
BACKGROUND OF THE INVENTION
References which are cited in the present disclosure are not necessarily prior art and therefore their citation does not constitute an admission that such references are prior art in any jurisdiction. All publications, patents and patent applications herein are incorporated by reference to the same extent as if each individual or patent application was specifically and individually indicated to be incorporated by reference.
There are 19 states in India are affected by various forms of fluorosis, including dental, skeletal, and non-skeletal manifestations. According to World Health Organization (WHO) guidelines, the maximum permissible fluoride level in drinking water is set at 1.5 mg/L, while the arsenic limit is 10 ppb. Therefore, it is crucial to remove excessive fluoride and arsenic from groundwater using groundbreaking bio-ceramic nanocomposites. The bio-ceramic nanocomposites offer an environmentally friendly and non-hazardous approach for earth-friendly purification of fluoride and arsenic in groundwater systems. The developed bio-ceramic nanocomposites achieve safe water purification while being cost-effective and ecologically friendly and highly efficient in their removal of pollutants.
High fluoride levels in drinking water led to dental fluorosis, causing tooth discoloration, and skeletal fluorosis, resulting in bone deformities and joint pain. Prolonged exposure to fluoride can harm the nervous system, affect infant development, damage kidneys, and disrupt thyroid function. Arsenic contamination in drinking water causes arsenicosis, leading to skin lesions, pigmentation changes, and an increased risk of cancers (skin, lung, bladder, and kidney). Chronic arsenic exposure contributes to cardiovascular diseases, neurological disorders, immune suppression, and organ damage. Due to its persistence and bioaccumulation in groundwater, arsenic contamination poses a severe public health threat requiring urgent remediation. Several nanomaterials have been developed to remove excess fluoride and arsenic separately. However, in this study, we develop bio-ceramic nanomaterials capable of removing both arsenic and fluoride from groundwater simultaneously.
A more effective solution for the simultaneous removal of fluoride and arsenic toxins is achievable through nano-sized bio-ceramics. Using these materials, 95% of fluoride and 92% of arsenic can be removed from contaminated groundwater by cost effective method.
Alum, bone char, zeolites were developed for the removal of fluoride content and the titanium dioxide, iron-based adsorbents, Reverse Osmosis (RO) methods are costliest methods or materials for the removal of fluorine and arsenic contents.
The present invention is designed for the removal of fluoride and arsenic toxic elements from groundwater, wastewater, and industrial pollutants. The sorbent material is prepared using a simple method, making it suitable for practical applications in treating large volumes of water contaminated with excessive fluoride and arsenic.
Several patents issued for heavy metal ions removal but none of these are related to the present invention. Patent WO2018122871A1 provides discloses an adsorbent composition of chitosan reinforced mixed oxide granular nanocomposite for water-related applications, specifically for water purification. The granular nanocomposite comprises active ingredients homogenized in the aggregated network of chitosan templated aluminum oxyhydroxide/2-line iron oxyhydroxide composite. The composition is versatile as any metal or non-metal ion (including transition metals and/or rare earth metals) can be used. The composition itself can be a water purifier, such as an adsorbent for fluoride and arsenic removal from water with excessively high fluoride and arsenic adsorption capacity.
Another patent US11766641B2 relates to nanoadsorbent based filter is used for purification of fluoride and arsenic contaminated water. 140-150 g low cost (˜10 USD/kg) nanoparticles of gamma alumina of 20-25 mg/g fluoride and 25-30 mg/g arsenic adsorption capacity is incorporated in propylene filter without susceptibility of leaching incorporated nanoparticles in water. The cost of domestic defluoridation device containing low cost nanoalumina incorporated filters/cartridges along with housing, overhead tank, tubing and treated water storage container etc. is of very low cost of around 25 USD/device. The fluoride treatment cost would be <0.5 USD/100 lit for 4-5 mg/l fluoride water after 2-3 regenerations while, the arsenic treatment cost using domestic filtration device would be <0.25 USD/100 lit for 90-100 μg/l arsenic (III) water. A method incorporates nanoadsorbent in a sediment removal filter candle and provides a household defluoridation device capable of treatment of fluoride and arsenic contaminated ground/drinking water without electricity.
Another patent WO2009152172A2 provides bio-ceramic compositions for removing fluoride from water, and methods for making the same are disclosed. The bio-ceramic composition may comprise alumina, calcium oxide, sulfur, and/or carbon. The bio-ceramic composition may be produced from at least one natural media, such as chitin or eggshell membrane. The bio-ceramic composition may realize an initial fluoride adsorption capacity, in water, of at least about 5 mg/g.
Another patent CN101163530A discloses the treatment of water containing unwanted species, including but not limited to arsenic, selenium or alum, to remove these contaminants. Compositions and methods and for contaminants from water are provided. The compositions comprise ferric hydroxide and ferric oxyhydride coated substrates for use in removing the contaminant from the water. Contacting water bearing the contaminant with the substrates can substantially reduce contaminant levels therein. Methods of oxidizing the contaminants in water to facilitate their removal by the ferric hydroxide and ferric oxyhydride coated substrates are also provided. The contaminants include, but are not limited to, arsenic, selenium, uranium, lead, cadmium, nickel, copper, zinc, chromium and vanadium, their oxides and soluble salts therof.
Another patent US20190106337A1 provide relates to compositions and methods for removing contaminants from a fluid, and more particularly, for removing arsenic and/or heavy metals from water. A medium for removal of a contaminant in a fluid is provided. The medium includes, when in dry form: about 90% or greater by weight of aluminum oxide; about 0.1% to about 2.0% by weight of zero valent iron (ZVI); and about 1% to about 5% by weight of carbon. Methods for producing the medium are also provided.
OBJECTS OF THE INVENTION
Main object of the present invention is to groundbreaking bio-ceramic nanocomposites for groundwater decontamination of fluoride and arsenic.
Another object of the present invention is to provide a cost-effective and scalable method for the synthesis of bio-ceramic nanocomposites using simple precursors and microwave-assisted techniques.
Another object of the present invention is to achieve high removal efficiency—up to 95% for fluoride and 92% for arsenic—from aqueous solutions, making the treated water safe for human consumption as per WHO guidelines.
Another object of the present invention is to offer an environmentally friendly and non-toxic solution for water purification that minimizes the use of hazardous chemicals or expensive equipment.
Another object of the present invention is to address the limitations of existing water treatment technologies, such as high operational costs, complex procedures, and inability to remove both fluoride and arsenic simultaneously
SUMMARY OF THE INVENTION
This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention.
This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.
To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings.
The present invention provides a novel, cost-effective, and eco-friendly solution for the simultaneous removal of fluoride and arsenic from contaminated groundwater using bio-ceramic nanocomposites. Synthesized through a simple microwave-assisted method using calcium nitrate and ammonium phosphate, the nanocomposites exhibit high adsorption efficiency, achieving up to 95% fluoride and 92% arsenic removal. This invention addresses a critical need in water purification by offering a sustainable, non-toxic alternative to existing technologies, making it suitable for large-scale deployment in both rural and urban areas affected by water contamination.
Herein enclosed a bio-ceramic nanocomposite material for simultaneous removal of fluoride and arsenic from groundwater.
A method to prepare bio-ceramic nanocomposite comprising the steps of:
Preparing a 1M solution of calcium nitrate tetrahydrate (Ca(NO3)2⋅4H2O)(Ca(NO₃)₂·4H₂O)(Ca(NO3)2⋅4H2O) and adjusting the pH to 10–11;
Preparing a 0.6 M solution of ammonium hydrogen phosphate ((NH4)2HPO4)((NH₄)₂HPO₄)((NH4)2HPO4) with a similar pH range of 10–11;
Adding the phosphate solution dropwise to the calcium nitrate solution under continuous stirring;
Stirring the mixture for 2 hours at room temperature while maintaining the pH between 10 and 11;
Subjecting the stirred mixture to microwave irradiation using a domestic microwave (2.45 GHz, 800 W) for 10 to 30 minutes;
Allowing the irradiated mixture to age undisturbed for 12 to 15 hours; and
Washing the aged product thoroughly and drying it in a vacuum oven at 70 °C to obtain the final bio-ceramic nanocomposite
DETAILED DESCRIPTION OF THE INVENTION
The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.
It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a",” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
In addition, the descriptions of "first", "second", “third”, and the like in the present invention are used for the purpose of description only, and are not to be construed as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" and "second" may include at least one of the features, either explicitly or implicitly.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
In some embodiments of the present invention, groundbreaking bio-ceramic nanocomposites for groundwater decontamination of fluoride and arsenic.
In some embodiments of the invention, dissolved calcium nitrate tetrahydrate [Ca(NO₃)₂·4H₂O] in distilled water to obtain a 1 M solution. Adjust the pH to 10–11 using an appropriate base (e.g., ammonia solution or NaOH).
In some embodiments of the invention, prepared a 0.6 M solution of ammonium hydrogen phosphate [(NH₄)₂HPO₄] in distilled water and similarly adjust its pH to 10–11.
In some embodiments of the invention, added the (NH₄)₂HPO₄ solution dropwise to the calcium nitrate solution under constant stirring to ensure homogeneous mixing and reaction. Maintain the pH at 10–11 during the entire addition process.
In some embodiments of the invention, continued stirring the mixed solution for 2 hours at room temperature to allow complete reaction and formation of precursor material.
In some embodiments of the invention, subjected the resulting mixture to microwave irradiation using a domestic microwave oven operating at 2.45 GHz and 800 W for a period of 10 to 30 minutes. This promotes nucleation and controlled growth of the nanocomposite particles.
In some embodiments of the invention, allowed the irradiated product to age undisturbed for 12–15 hours to enhance crystallinity and structural stability of the nanocomposites.
In some embodiments of the invention, washed the aged product thoroughly with distilled water to remove unreacted salts and by-products. Dry the final material in a vacuum oven at 70 °C until completely moisture-free.
Herein enclosed a bio-ceramic nanocomposite material for simultaneous removal of fluoride and arsenic from groundwater.
A method to prepare bio-ceramic nanocomposite comprising the steps of:
Preparing a 1M solution of calcium nitrate tetrahydrate (Ca(NO3)2⋅4H2O)(Ca(NO₃)₂·4H₂O)(Ca(NO3)2⋅4H2O) and adjusting the pH to 10–11;
Preparing a 0.6 M solution of ammonium hydrogen phosphate ((NH4)2HPO4)((NH₄)₂HPO₄)((NH4)2HPO4) with a similar pH range of 10–11;
Adding the phosphate solution dropwise to the calcium nitrate solution under continuous stirring;
Stirring the mixture for 2 hours at room temperature while maintaining the pH between 10 and 11;
Subjecting the stirred mixture to microwave irradiation using a domestic microwave (2.45 GHz, 800 W) for 10 to 30 minutes;
Allowing the irradiated mixture to age undisturbed for 12 to 15 hours; and
Washing the aged product thoroughly and drying it in a vacuum oven at 70 °C to obtain the final bio-ceramic nanocomposite.
EXAMPLE 1
BEST METHOD
The current approach focuses on the effective simultaneous removal of fluoride and arsenic using nano-bioceramic materials. This method is cost-effective, eco-friendly, and non-toxic, achieving 95% fluoride removal and 92% arsenic removal efficiency.
• A 1M solution of calcium nitrate tetrahydrate (Ca(NO3)2⋅4H2O)(Ca(NO₃)₂·4H₂O)(Ca(NO3)2⋅4H2O) was prepared and adjusted to a pH of 10–11.
• A 0.6 M solution of ammonium hydrogen phosphate ((NH4)2HPO4)((NH₄)₂HPO₄)((NH4)2HPO4) was prepared separately and maintained at the same pH range (10–11).
• The phosphate solution was added dropwise to the calcium nitrate solution under continuous stirring.
• The resulting mixture was stirred for 2 hours at room temperature while maintaining the pH between 10 and 11.
• The stirred mixture was then subjected to microwave irradiation using a domestic microwave oven operating at 2.45 GHz and 800 W, for a duration of 10 to 30 minutes.
• After microwave treatment, the product was aged undisturbed for 12 to 15 hours.
• Finally, the aged product was washed thoroughly and dried in a vacuum oven at 70 °C to obtain the bio-ceramic nanocomposite powder.

, Claims:1. A bio-ceramic nanocomposite material for simultaneous removal of fluoride and arsenic from groundwater.
2. A method to prepare bio-ceramic nanocomposite as claimed in claim 1, wherein the nanocomposite is prepared comprising the steps of:
a) Preparing a 1 M solution of calcium nitrate tetrahydrate (Ca(NO3)2⋅4H2O)(Ca(NO₃)₂·4H₂O)(Ca(NO3)2⋅4H2O) and adjusting the pH to 10–11;
b) Preparing a 0.6 M solution of ammonium hydrogen phosphate ((NH4)2HPO4)((NH₄)₂HPO₄)((NH4)2HPO4) with a similar pH range of 10–11;
c) Adding the phosphate solution dropwise to the calcium nitrate solution under continuous stirring;
d) Stirring the mixture for 2 hours at room temperature while maintaining the pH between 10 and 11;
e) Subjecting the stirred mixture to microwave irradiation using a domestic microwave (2.45 GHz, 800 W) for 10 to 30 minutes;
f) Allowing the irradiated mixture to age undisturbed for 12 to 15 hours; and
g) Washing the aged product thoroughly and drying it in a vacuum oven at 70 °C to obtain the final bio-ceramic nanocomposite.