Nuclear waste recycling

Why health and fatality risk and suffering?

Recycle, Reuse, Repurpose,
Refuel & Renew (5R)

Radioactive waste to clean H2 and non-radioactive products

Why dump and risk ecosystem?

Nuclear waste recycling

MSDS - Entity 1: Transforming Greenhouse Gases to Energy and Valuable Materials

Nuclear waste recycling

01.

.

Physical

Incineration Distillation
EvaporationDumping

02.

.

Chemical

Precipitation Wet Oxidation Acid Digestion

03.

.

Biological

Microbial Remediation via MECC Microbial digestion

General Methods of radioactive waste recycling - Recycling methods

Entity 1 | Electrochemical reactions of CO2 and N2

Electrocatalytic conversion of GHG emissions from petrochemical industries

The electrocatalytic conversion of GHG emissions to Value Added Products (VAPs) including ethanol is carried out employing electrochemical reactor at ambient of 28oC, 1 atms pressure and flow rate of emissions from petrochemical industry roughly 500ml/min. The initiator solution is acidified with 50 ml of conc. HCl. The acidified solution generates in-house hydrogen gas to facilitate the reduction of GHG emissions with carbon in the form of CO2, CO, CH4, ethane, N2, SOx, NOx, S, H2S etc into ethanol, acetates and 5-methyl –phenylazothiophene – 2 – azo dye.

Thus, from the HR-MS spectra of liquid and solid products of the GHG emissions electrocatalytic reduction as ethanol, Mg acetoethoxide, Cupric ethoxide, cuprous ethoxide, 5-methyl-phenyl azo thiophene-azo dye. Depending on the variation in constituents and composition of the input GHG emissions, either ethanol or 5-methyl-phenyl azo thiophene-azo dye or acetic acid can be fine-tuned to be the major product.

Electrocatalytic conversion of GHG emissions from petrochemical industries

Electrochemical separation and agglomeration of iron ore in steel slag

Steel slag is a by-product obtained in the steel production plants and also presents huge challenge in the solid waste disposal. The steel slag although considered as solid waste also possess several valuable elements such as titanium, nickel, Zinc, iron, aluminum, silica so on and so forth. These elements or compounds when extracted by chemical or physical process results in value addition in diverse fields of applications such as wastewater treatment to semiconductor devices. It can be understood from the literature that the leaching technique was the most widely used in the resource recovery domain followed by other techniques like fusion, hydrothermal treatment. As iron is the major constituent of steel production, any Fe content in the slag can be recovered electrochemically and utilize the silica content in the slag to encapsulate the same to avoid from environmental reactions and corrosion. The major advantage of Entity1 solution is that it can separate the minerals or elements at concentrations as low as parts per million (ppm) or parts per billion (ppb) (Ref: 202341000490).

Silicon Ingots From Refractory Bricks and Steel Sludge, Slag Industrial Wastes

Steel slag is a by-product obtained in the steel production plants and also presents huge challenge in the solid waste disposal. The steel slag although considered as solid waste also possess several valuable elements such as titanium, nickel, Zinc, iron, aluminum, silica so on and so forth. These elements or compounds when extracted by chemical or physical process results in value addition in diverse fields of applications such as wastewater treatment to semiconductor devices. It can be understood from the literature that the leaching technique was the most widely used in the resource recovery domain followed by other techniques like fusion, hydrothermal treatment.
Refractory bricks from steel plants are mostly silicon dioxide (> 70-98%). These refractory
bricks are rich source of semiconductor materials like Si and SiC upon proper processing. In
addition, steel sludge a waste material from steel industries possesses > 70% of SiO 2 that can be processed to Si or SiC.

Oil & Gas

The electrochemical reactions of CO2 and N2 are of interest for the synthesis of chemicals and for approaches to decrease global warming. Work has been done looking at synthesizing specialty chemicals such as formate, acetates, urea, methanol, ethanol, isoamyl alchol and n-butanol from CO2 and N2 gas combination. Most of the thermal power plants emit flue gas with combination of < 20% of CO2, 80-85% of N2 and small amounts of other gases like SOx and NOx. As these flue gases are let out into the atmosphere, they increase GHG emissions and also the chemically inert and important energy carrier N2 gas is left unused. To reduce the GHG emissions and to utilize the excess N2 gas untapped so far in thermal power plant exhausts we propose our patented and proprietary electrocatalytic conversion process where the CO2 is reduced to fuels such as methanol, ethanol, butanol, isoamyl alcohol, acetates so on and so forth, whereas N2 can be reduced to the most important energy carrier Ammonia or amides like urea (fertilizer), amines and imines (hydrogen storage or carriers).

As N2 reduction to ammonia is normally carried out by Haber-Bosch process which is energy intensive process occurring at very high temperatures and pressure. High temperature is required to achieve N≡ N bond breaking, whereas high pressure is achieved to increase the reaction rate . In the proposed electrocatalytic technique, ammonia is formed by electrocatalytic process where the reaction occurs at ambient temperature and pressure and hence less energy intensive. The electrocatalyst utilized is also cost-effective such as carbonaceous compounds or metal foam embedded carbon electrocatalysts leading to near 100% conversion efficiency and > 90% Faradaic efficiency.

For a representative composition of flue gas and the tentative products that can be achieved from the flue gas employing the Electrocatalytic Reduction Process is as provided in the Table below

In case of Gas industries, the VAPs obtained are

Distilleries

Electrochemical conversion of carbon dioxide and conversion into Ethanol (Patent Number: 524748; PCT/2023/050840)

The electrochemical reactions of CO2 are of interest for the synthesis of chemicals and for approaches to decrease global warming.
Far greater impact on decreasing atmospheric CO2 levels might be obtained by synthesizing fuels.
The main advantages of such carbon-based fuels, vs. storing electricity in batteries or as hydrogen, are the ease of use within existing infrastructures and the higher energy density.
Key discovery is the direct electrocatalytic reduction of CO2 to ethanol @ Faradaic efficiency upto 85% at RT.

Entity 1 | Emissions-to-Value Added Products

Physical Method

Evaporation: removal of salts, heavy metals and other hazardous & radioactive waste

Reduction of volume of radioactive waste and other toxic materials from LLW & ILW
Highly expensive due to its high-energy requirement
High amount of inactive salts leads to slowdown
Evaporation in organic salts leads to explosion

Incineration or Pyrolysis (High Temperature)

Releasing CO2, H2O, S, and HC1 as by-product
Requires gas-filtering systems to control radioactive discharges.
Thickening and removal of water need pretreatment

Advantage:

H2: 120-142 MJ/kg
Gasoline: 44-51 MJ/kg From radioactive waste

Distillation: Involves reduction of volume of radioactive waste in solid

Pretreatment technique of incineration
Requires high energy and slow output

Environmental & health benefits

2.2 pounds (1 kg) of H2 gas = the energy in 1 gallon (6.2 pounds, 2.8 kgs) of gasoline
Hydrogen is abundant stored in H2O, hydrocarbons & other organic matter

Distillation: Involves reduction of volume of radioactive waste in solid

Radioactive waste is treated, in chronological order Incineration, evaporation and compaction to avoid contamination
Radioactive waste remain forever buried
Possibilities of leakage and contamination into the ground water or into the ocean
Other physical methods: cutting, decontamination, sedimentation, land fill
Ineffective in the treatment of radioactive waste
Need for novel methods to treat the radioactive waste!!!

Chemical Methods

Acid digestion: Radioactive waste is decomposed by strong acid in mixtures like nitric acid and phosphoric acid

High temperature with adequate atmosphere pressure leading to bond breaking in waste
Products are inorganic liquids and gases (O2, CO2)
Oxidative destruction technology
Oxidizes the organic liquid wastes (cellulose, latex rubber, polyethylene, plastic, oils and other organic materials).

Chemical precipitation: Aqueous radioactive waste

Manage and remove radioactive substances from LLW and ILW
Radioactive components removed by precipitation and sorption

Wet Oxidation: of dissolved or suspended components of waste, organic liquid radioactive waste

Pretreatment technique of incineration
Requires high energy and slow output

Biological Methods

Mesophilic bacteria available in environment

Klebsiella Oxyoetica
Ponteae agglomerans
Klebsiella stutseli
Pseudomonas putida

Resistance to radiation from nuclear graphite at levels up to 1.055 ± 0.067 BqµL-1

Klebsiella Oxyoetica
Klebsiella Stutseli
Pseudomonas Agglomerans
76% efficiency
Mostly for LLW and PoPs with radioactivity (organic solvents)

Low Level Waste

Bulk of natural graphite from Gen IV fast reactors
14C from aromatic organic solvents used in nuclear industries and hospitals
Waste water stream with organic pollutants
Highest environmental risk via Total Carbon Content (TOC) and toxicity
Best solution involving locally available microorganisms

General Methods of radioactive waste recycling - Recycling methods

Electrocatalytic conversion of GHG emissions from petrochemical industries

The electrocatalytic conversion of GHG emissions to Value Added Products (VAPs) including ethanol is carried out employing electrochemical reactor at ambient of 28oC, 1 atms pressure and flow rate of emissions from petrochemical industry roughly 500ml/min. The initiator solution is acidified with 50 ml of conc. HCl. The acidified solution generates in-house hydrogen gas to facilitate the reduction of GHG emissions with carbon in the form of CO2, CO, CH4, ethane, N2, SOx, NOx, S, H2S etc into ethanol, acetates and 5-methyl –phenylazothiophene – 2 – azo dye.

Thus, from the HR-MS spectra of liquid and solid products of the GHG emissions electrocatalytic reduction as ethanol, Mg acetoethoxide, Cupric ethoxide, cuprous ethoxide, 5-methyl-phenyl azo thiophene-azo dye. Depending on the variation in constituents and composition of the input GHG emissions, either ethanol or 5-methyl-phenyl azo thiophene-azo dye or acetic acid can be fine-tuned to be the major product.

Electrocatalytic conversion of GHG emissions from petrochemical industries

Electrochemical separation and agglomeration of iron ore in steel slag

Steel slag is a by-product obtained in the steel production plants and also presents huge challenge in the solid waste disposal. The steel slag although considered as solid waste also possess several valuable elements such as titanium, nickel, Zinc, iron, aluminum, silica so on and so forth. These elements or compounds when extracted by chemical or physical process results in value addition in diverse fields of applications such as wastewater treatment to semiconductor devices. It can be understood from the literature that the leaching technique was the most widely used in the resource recovery domain followed by other techniques like fusion, hydrothermal treatment. As iron is the major constituent of steel production, any Fe content in the slag can be recovered electrochemically and utilize the silica content in the slag to encapsulate the same to avoid from environmental reactions and corrosion. The major advantage of Entity1 solution is that it can separate the minerals or elements at concentrations as low as parts per million (ppm) or parts per billion (ppb) (Ref: 202341000490).

Silicon Ingots From Refractory Bricks and Steel Sludge, Slag Industrial Wastes

Steel slag is a by-product obtained in the steel production plants and also presents huge challenge in the solid waste disposal. The steel slag although considered as solid waste also possess several valuable elements such as titanium, nickel, Zinc, iron, aluminum, silica so on and so forth. These elements or compounds when extracted by chemical or physical process results in value addition in diverse fields of applications such as wastewater treatment to semiconductor devices. It can be understood from the literature that the leaching technique was the most widely used in the resource recovery domain followed by other techniques like fusion, hydrothermal treatment.
Refractory bricks from steel plants are mostly silicon dioxide (> 70-98%). These refractory
bricks are rich source of semiconductor materials like Si and SiC upon proper processing. In
addition, steel sludge a waste material from steel industries possesses > 70% of SiO 2 that can be processed to Si or SiC.

Oil & Gas

The electrochemical reactions of CO2 and N2 are of interest for the synthesis of chemicals and for approaches to decrease global warming. Work has been done looking at synthesizing specialty chemicals such as formate, acetates, urea, methanol, ethanol, isoamyl alchol and n-butanol from CO2 and N2 gas combination. Most of the thermal power plants emit flue gas with combination of < 20% of CO2, 80-85% of N2 and small amounts of other gases like SOx and NOx. As these flue gases are let out into the atmosphere, they increase GHG emissions and also the chemically inert and important energy carrier N2 gas is left unused. To reduce the GHG emissions and to utilize the excess N2 gas untapped so far in thermal power plant exhausts we propose our patented and proprietary electrocatalytic conversion process where the CO2 is reduced to fuels such as methanol, ethanol, butanol, isoamyl alcohol, acetates so on and so forth, whereas N2 can be reduced to the most important energy carrier Ammonia or amides like urea (fertilizer), amines and imines (hydrogen storage or carriers).

As N2 reduction to ammonia is normally carried out by Haber-Bosch process which is energy intensive process occurring at very high temperatures and pressure. High temperature is required to achieve N≡ N bond breaking, whereas high pressure is achieved to increase the reaction rate . In the proposed electrocatalytic technique, ammonia is formed by electrocatalytic process where the reaction occurs at ambient temperature and pressure and hence less energy intensive. The electrocatalyst utilized is also cost-effective such as carbonaceous compounds or metal foam embedded carbon electrocatalysts leading to near 100% conversion efficiency and > 90% Faradaic efficiency.

For a representative composition of flue gas and the tentative products that can be achieved from the flue gas employing the Electrocatalytic Reduction Process is as provided in the Table below

In case of Gas industries, the VAPs obtained are

Distilleries

Electrochemical conversion of carbon dioxide and conversion into Ethanol (Patent Number: 524748; PCT/2023/050840)

The electrochemical reactions of CO2 are of interest for the synthesis of chemicals and for approaches to decrease global warming.
Far greater impact on decreasing atmospheric CO2 levels might be obtained by synthesizing fuels.
The main advantages of such carbon-based fuels, vs. storing electricity in batteries or as hydrogen, are the ease of use within existing infrastructures and the higher energy density.
Key discovery is the direct electrocatalytic reduction of CO2 to ethanol @ Faradaic efficiency upto 85% at RT.

Physical Method

Evaporation: removal of salts, heavy metals and other hazardous & radioactive waste

Reduction of volume of radioactive waste and other toxic materials from LLW & ILW

Highly expensive due to its high-energy requirement

High amount of inactive salts leads to slowdown

Evaporation in organic salts leads to explosion

Incineration or Pyrolysis (High Temperature)

Releasing CO2, H2O, S, and HC1 as by-product
Requires gas-filtering systems to control radioactive discharges.
Thickening and removal of water need pretreatment

Distillation: Involves reduction of volume of radioactive waste in solid

Pretreatment technique of incineration
Requires high energy and slow output

Advantage:

H2: 120-142 MJ/kg
Gasoline: 44-51 MJ/kg From radioactive waste

Environmental & health benefits

2.2 pounds (1 kg) of H2 gas = the energy in 1 gallon (6.2 pounds, 2.8 kgs) of gasoline
Hydrogen is abundant stored in H2O, hydrocarbons & other organic matter

Distillation: Involves reduction of volume of radioactive waste in solid

Radioactive waste is treated, in chronological order Incineration, evaporation and compaction to avoid contamination

Radioactive waste remain forever buried
Possibilities of leakage and contamination into the ground water or into the ocean

Other physical methods: cutting, decontamination, sedimentation, land fill

Ineffective in the treatment of radioactive waste

Need for novel methods to treat the radioactive waste!!!

Chemical Methods

Acid digestion: Radioactive waste is decomposed by strong acid in mixtures like nitric acid and phosphoric acid

High temperature with adequate atmosphere pressure leading to bond breaking in waste

Products are inorganic liquids and gases (O2, CO2)

Oxidative destruction technology

Oxidizes the organic liquid wastes (cellulose, latex rubber, polyethylene, plastic, oils and other organic materials).

Chemical precipitation: Aqueous radioactive waste

Manage and remove radioactive substances from LLW and ILW

Radioactive components removed by precipitation and sorption

Wet Oxidation: of dissolved or suspended components of waste, organic liquid radioactive waste

Pretreatment technique of incineration

Requires high energy and slow output

Biological Methods

Mesophilic bacteria available in environment

Klebsiella Oxyoetica

Ponteae agglomerans
Klebsiella stutseli
Pseudomonas putida

Chemical precipitation: Aqueous radioactive waste

Klebsiella Oxyoetica

Klebsiella Stutseli

Pseudomonas Agglomerans

76% efficiency

Mostly for LLW and PoPs with radioactivity (organic solvents)

Low Level Waste

Bulk of natural graphite from Gen IV fast reactors

14C from aromatic organic solvents used in nuclear industries and hospitals

Waste water stream with organic pollutants

Highest environmental risk via Total Carbon Content (TOC) and toxicity

Best solution involving locally available microorganisms

Major radioactive elements: 238U/235U, 137Cs, 237Np, 239Pu, 241Am, 99Tc, and 90Sr can be treated to reduced insoluble, immobilized and precipitated form Based on the redox property of a radioactive element, each microbe has its own way of interaction with different heavy metals and radioactive elements.

Classification of Radioactive waste

Process of removal/disposal of radioactive waste by microorganism in electrochemical reactor

Metabolic activity of microorganism helps in the removal and conversion of radioactive compound to less radioactive/non-radioactive form.

Microbial remediation depends upon the physical, chemical, and biological properties of the microbe.

Involves oxidation, reduction, dissolution, precipitation, sorption, and leach processes greatly influencing the reduction of toxicity of the radioactive waste

Deinococcus radiodurans

Extremophile, ability to live in extreme condition (high-temperature and high-radiation exposure)

Bacillus sphaericus

Capability to bind and store large amount of radioactive metals, in the paracrystalline proteinaceous surface S-layer

Pseudomonas strain

Capable of intracellular sequestering of U and Th by biosorption

Ref: Environmental Science and Pollution Research

https://doi.org/10.1007/s11356-020-08404-0,

Radioactive element	Half Life	Microorganism	Interaction
Strontium 90Sr	29 years	Micrococcus luteus	Bio accumulation of Sr has been reported for several microorganism. The Sr binding to the cell envelope of the M. luteus is sensitive to pre- treatment. Radio strontium incorporation into carbonate phases is desirable.
Cesium 137Cs	30 years	Bacteria isolated from soil [E.coliKup(Trko)]	Specific Cs transport via the E.coliKup (TRKO) IS THE ONLY MICROORGANISM FOR WHICH NO WELL define K+ transport mutants are available.
Plautonium 239Pu	24,100 years	S. putrefacieans G. metallireducens B. subtilis	Direct enzymatic reduction of Pu(VI) and Pu(V) to Pu(IV) more stable and oxidized state of Pu by bacterial cell suspension. The Pu(VI) was sorbed to the bacterial cell surface through complexation with phosphate groups of the cells by B. subtilis.
Neptunium 237Np	2.14 x 10^6 years	Shewanella putrefaciens Desulfovibrio desulfuricans	Reduction of Np(V) {NpO2 highly radioactive, highly soluble} to Np(IV) by cell suspension of S.putrifaciensMR-1 and also by sulfate-reducing bacterial D. desulfuricans.
Uranium 238U 235U	4.41 x 10^9 years	Geobacter sulfurrenducens	Microbial bio transfer\reduction of toxic, soluble, mobilized {U(VI)} insoluble mineral uraninite as potential mechanism. Two step process: enzymatic reduction of U(VI) to U(V), then disproportionation of U(V) to U(IV).

Radioactive element	Half Life	Microorganisms	Interaction
Strontium 90Sr	29 years	Micrococcus luteus	Bio accumulation of Sr has been reported for several microorganism. The Sr binding to the cell envelope of the M. luteus is sensitive to pre- treatment. Radio strontium incorporation into carbonate phases is desirable.
Cesium 137Cs	30 years	Bacteria isolated from soil [E.coliKup(Trko)]	Specific Cs transport via the E.coliKup (TRKO) IS THE ONLY MICROORGANISM FOR WHICH NO WELL define K+ transport mutants are available.
Plautonium 239Pu	24,100 years	S. putrefacieans<br> G. metallireducens <br> B. subtilis	Direct enzymatic reduction of Pu(VI) and Pu(V) to Pu(IV) more stable and oxidized state of Pu by bacterial cell suspension. The Pu(VI) was sorbed to the bacterial cell surface through complexation with phosphate groups of the cells by B. subtilis.
Neptunium 237Np	2.14 x 10^6 years	Shewanella putrefaciens Desulfovibrio desulfuricans	Reduction of Np(V) {NpO2 highly radioactive, highly soluble} to Np(IV) by cell suspension of S.putrifaciensMR-1 and also by sulfate-reducing bacterial D. desulfuricans.
Uranium 238U 235U	4.41 x 10^9 years	Geobacter sulfurrenducens	Microbial bio transfer\reduction of toxic, soluble, mobilized {U(VI)} insoluble mineral uraninite as potential mechanism. Two step process: enzymatic reduction of U(VI) to U(V), then disproportionation of U(V) to U(IV).

Plausible pathways to recycle radioactive waste

References

IAEA (1970) Standardization of radioactive waste categories. Technical Reports Series No. 101. International Atomic Energy Agency, (IAEA), Vienna

IAEA (1992) Treatment and conditioning of radioactive organic liquids., IAEA-TEC-DOC-656. International Atomic Energy Agency, Vienna

IAEA (1994, Classification of radioactive waste, Safety Series. No.111- G-1.1. International Atomic Energy Agency (IAEA), Vienna

IAEA (2001a) Decontamination and decommissioning of nuclear facilities. Technical Reports Series No. 401. International Atomic Energy Agency, Vienna

IAEA (2001b), Handling and processing of radioactive waste from applications. Technical Reports Series No. 401. International Atomic Energy Agency, Vienna

IAEA (2001c) Report series no. 401. Methods for the minimization of radioactive waste from decontamination and decommissioning of nuclear facilities. International Atomic Energy Agency (IAEA), Vienna

IAEA (2002) Application of ion exchange process for the treatment of radioactive waste and management of spent ion exchanger. Technical Reports Series No. 408. International Atomic Energy Agency, Vienna

IAEA (2004) Application of the concepts of exclusions, exemption and clearance. IAEA Safety standards Series No. RS-G-1.7. International Atomic Energy Agency (IAEA), Vienna

IAEA (2006a) Fundamental safety principles. IAEA SAFETY STANDARDS SERIES. SF-1, IAEA, Vienna

IAEA (2006b) Application of thermal technologies for processing of radioactive waste. IAEA-TECDOC-1527. International Atomic Energy Agency (IAEA), Vienna

ADP

Anaerobic Cathodic Reaction

Endogeneous electron reserves+NADH +H2

General Methods of radioactive waste recycling - Recycling methods

Electrocatalytic conversion of GHG emissions from petrochemical industries

The electrocatalytic conversion of GHG emissions to Value Added Products (VAPs) including ethanol is carried out employing electrochemical reactor at ambient of 28oC, 1 atms pressure and flow rate of emissions from petrochemical industry roughly 500ml/min. The initiator solution is acidified with 50 ml of conc. HCl. The acidified solution generates in-house hydrogen gas to facilitate the reduction of GHG emissions with carbon in the form of CO2, CO, CH4, ethane, N2, SOx, NOx, S, H2S etc into ethanol, acetates and 5-methyl –phenylazothiophene – 2 – azo dye.

Thus, from the HR-MS spectra of liquid and solid products of the GHG emissions electrocatalytic reduction as ethanol, Mg acetoethoxide, Cupric ethoxide, cuprous ethoxide, 5-methyl-phenyl azo thiophene-azo dye. Depending on the variation in constituents and composition of the input GHG emissions, either ethanol or 5-methyl-phenyl azo thiophene-azo dye or acetic acid can be fine-tuned to be the major product.

Electrocatalytic conversion of GHG emissions from petrochemical industries

Electrochemical separation and agglomeration of iron ore in steel slag

Steel slag is a by-product obtained in the steel production plants and also presents huge challenge in the solid waste disposal. The steel slag although considered as solid waste also possess several valuable elements such as titanium, nickel, Zinc, iron, aluminum, silica so on and so forth. These elements or compounds when extracted by chemical or physical process results in value addition in diverse fields of applications such as wastewater treatment to semiconductor devices. It can be understood from the literature that the leaching technique was the most widely used in the resource recovery domain followed by other techniques like fusion, hydrothermal treatment. As iron is the major constituent of steel production, any Fe content in the slag can be recovered electrochemically and utilize the silica content in the slag to encapsulate the same to avoid from environmental reactions and corrosion. The major advantage of Entity1 solution is that it can separate the minerals or elements at concentrations as low as parts per million (ppm) or parts per billion (ppb) (Ref: 202341000490).

Silicon Ingots From Refractory Bricks and Steel Sludge, Slag Industrial Wastes

Steel slag is a by-product obtained in the steel production plants and also presents huge challenge in the solid waste disposal. The steel slag although considered as solid waste also possess several valuable elements such as titanium, nickel, Zinc, iron, aluminum, silica so on and so forth. These elements or compounds when extracted by chemical or physical process results in value addition in diverse fields of applications such as wastewater treatment to semiconductor devices. It can be understood from the literature that the leaching technique was the most widely used in the resource recovery domain followed by other techniques like fusion, hydrothermal treatment.
Refractory bricks from steel plants are mostly silicon dioxide (> 70-98%). These refractory
bricks are rich source of semiconductor materials like Si and SiC upon proper processing. In
addition, steel sludge a waste material from steel industries possesses > 70% of SiO 2 that can be processed to Si or SiC.

Oil & Gas

The electrochemical reactions of CO2 and N2 are of interest for the synthesis of chemicals and for approaches to decrease global warming. Work has been done looking at synthesizing specialty chemicals such as formate, acetates, urea, methanol, ethanol, isoamyl alchol and n-butanol from CO2 and N2 gas combination. Most of the thermal power plants emit flue gas with combination of < 20% of CO2, 80-85% of N2 and small amounts of other gases like SOx and NOx. As these flue gases are let out into the atmosphere, they increase GHG emissions and also the chemically inert and important energy carrier N2 gas is left unused. To reduce the GHG emissions and to utilize the excess N2 gas untapped so far in thermal power plant exhausts we propose our patented and proprietary electrocatalytic conversion process where the CO2 is reduced to fuels such as methanol, ethanol, butanol, isoamyl alcohol, acetates so on and so forth, whereas N2 can be reduced to the most important energy carrier Ammonia or amides like urea (fertilizer), amines and imines (hydrogen storage or carriers).

As N2 reduction to ammonia is normally carried out by Haber-Bosch process which is energy intensive process occurring at very high temperatures and pressure. High temperature is required to achieve N≡ N bond breaking, whereas high pressure is achieved to increase the reaction rate . In the proposed electrocatalytic technique, ammonia is formed by electrocatalytic process where the reaction occurs at ambient temperature and pressure and hence less energy intensive. The electrocatalyst utilized is also cost-effective such as carbonaceous compounds or metal foam embedded carbon electrocatalysts leading to near 100% conversion efficiency and > 90% Faradaic efficiency.

For a representative composition of flue gas and the tentative products that can be achieved from the flue gas employing the Electrocatalytic Reduction Process is as provided in the Table below

In case of Gas industries, the VAPs obtained are

Distilleries

Electrochemical conversion of carbon dioxide and conversion into Ethanol (Patent Number: 524748; PCT/2023/050840)

The electrochemical reactions of CO2 are of interest for the synthesis of chemicals and for approaches to decrease global warming.
Far greater impact on decreasing atmospheric CO2 levels might be obtained by synthesizing fuels.
The main advantages of such carbon-based fuels, vs. storing electricity in batteries or as hydrogen, are the ease of use within existing infrastructures and the higher energy density.
Key discovery is the direct electrocatalytic reduction of CO2 to ethanol @ Faradaic efficiency upto 85% at RT.

Incineration or Pyrolysis (High Temperature)

Releasing CO2, H2O, S, and HC1 as by-product
Requires gas-filtering systems to control radioactive discharges.
Thickening and removal of water need pretreatment

Distillation: Involves reduction of volume of radioactive waste in solid

Pretreatment technique of incineration
Requires high energy and slow output

Advantage:

H2: 120-142 MJ/kg
Gasoline: 44-51 MJ/kg From radioactive waste

Environmental & health benefits

2.2 pounds (1 kg) of H2 gas = the energy in 1 gallon (6.2 pounds, 2.8 kgs) of gasoline
Hydrogen is abundant stored in H2O, hydrocarbons & other organic matter

Physical Method

Evaporation: removal of salts, heavy metals and other hazardous & radioactive waste

Reduction of volume of radioactive waste and other toxic materials from LLW & ILW

Highly expensive due to its high-energy requirement

High amount of inactive salts leads to slowdown

Evaporation in organic salts leads to explosion

Distillation: Involves reduction of volume of radioactive waste in solid

Radioactive waste is treated, in chronological order Incineration, evaporation and compaction to avoid contamination

Radioactive waste remain forever buried
Possibilities of leakage and contamination into the ground water or into the ocean

Other physical methods: cutting, decontamination, sedimentation, land fill

Ineffective in the treatment of radioactive waste

Need for novel methods to treat the radioactive waste!!!

Chemical Methods

Acid digestion: Radioactive waste is decomposed by strong acid in mixtures like nitric acid and phosphoric acid

High temperature with adequate atmosphere pressure leading to bond breaking in waste

Products are inorganic liquids and gases (O2, CO2)

Oxidative destruction technology

Oxidizes the organic liquid wastes (cellulose, latex rubber, polyethylene, plastic, oils and other organic materials).

Chemical precipitation: Aqueous radioactive waste

Manage and remove radioactive substances from LLW and ILW

Radioactive components removed by precipitation and sorption

Wet Oxidation: of dissolved or suspended components of waste, organic liquid radioactive waste

Pretreatment technique of incineration

Requires high energy and slow output

Biological Methods

Mesophilic bacteria available in environment

Klebsiella Oxyoetica

Ponteae agglomerans
Klebsiella stutseli
Pseudomonas putida

Chemical precipitation: Aqueous radioactive waste

Klebsiella Oxyoetica

Klebsiella Stutseli

Pseudomonas Agglomerans

76% efficiency

Mostly for LLW and PoPs with radioactivity (organic solvents)

Low Level Waste

Bulk of natural graphite from Gen IV fast reactors

14C from aromatic organic solvents used in nuclear industries and hospitals

Waste water stream with organic pollutants

Highest environmental risk via Total Carbon Content (TOC) and toxicity

Best solution involving locally available microorganisms

Nuclear waste recycling

Why health and fatality risk and suffering?

Recycle, Reuse, Repurpose, Refuel & Renew (5R)

Radioactive waste to clean H2 and non-radioactive products

Why dump and risk ecosystem?

Nuclear waste recycling

Nuclear waste recycling

01.

.

Physical

Incineration Distillation EvaporationDumping​

02.

.

Chemical

Precipitation Wet Oxidation Acid Digestion

03.

.

Biological

Microbial Remediation via MECC Microbial digestion

General Methods of radioactive waste recycling - Recycling methods

Electrocatalytic conversion of GHG emissions from petrochemical industries

Electrocatalytic conversion of GHG emissions from petrochemical industries

Electrochemical separation and agglomeration of iron ore in steel slag

Silicon Ingots From Refractory Bricks and Steel Sludge, Slag Industrial Wastes

Physical Method

Evaporation: removal of salts, heavy metals and other hazardous & radioactive waste

Reduction of volume of radioactive waste and other toxic materials from LLW & ILW

​Highly expensive due to its high-energy requirement

High amount of inactive salts leads to slowdown

Evaporation in organic salts leads to explosion

Incineration or Pyrolysis (High Temperature)

Releasing CO2, H2O, S, and HC1 as by-product

​Requires gas-filtering systems to control radioactive discharges.

Thickening and removal of water need pretreatment

Advantage:

H2: 120-142 MJ/kg

Gasoline: 44-51 MJ/kg From radioactive waste

Distillation: Involves reduction of volume of radioactive waste in solid

Pretreatment technique of incineration

Requires high energy and slow output

Environmental & health benefits

2.2 pounds (1 kg) of H2 gas = the energy in 1 gallon (6.2 pounds, 2.8 kgs) of gasoline

Hydrogen is abundant stored in H2O, hydrocarbons & other organic matter

Distillation: Involves reduction of volume of radioactive waste in solid

Radioactive waste is treated, in chronological order Incineration, evaporation and compaction to avoid contamination

Radioactive waste remain forever buried

Possibilities of leakage and contamination into the ground water or into the ocean

Other physical methods: cutting, decontamination, sedimentation, land fill

Ineffective in the treatment of radioactive waste

Need for novel methods to treat the radioactive waste!!!

General Methods of radioactive waste recycling - Recycling methods

Electrocatalytic conversion of GHG emissions from petrochemical industries

Electrocatalytic conversion of GHG emissions from petrochemical industries

Electrochemical separation and agglomeration of iron ore in steel slag

Silicon Ingots From Refractory Bricks and Steel Sludge, Slag Industrial Wastes

Physical Method

Evaporation: removal of salts, heavy metals and other hazardous & radioactive waste

Reduction of volume of radioactive waste and other toxic materials from LLW & ILW

Highly expensive due to its high-energy requirement​

High amount of inactive salts leads to slowdown

​Evaporation in organic salts leads to explosion

Incineration or Pyrolysis (High Temperature)

​Releasing CO2, H2O, S, and HC1 as by-product

Requires gas-filtering systems to control radioactive discharges.

Thickening and removal of water need pretreatment

Distillation: Involves reduction of volume of radioactive waste in solid

Pretreatment technique of incineration

Requires high energy and slow output

Advantage:

H2: 120-142 MJ/kg

Gasoline: 44-51 MJ/kg From radioactive waste

Environmental & health benefits

2.2 pounds (1 kg) of H2 gas = the energy in 1 gallon (6.2 pounds, 2.8 kgs) of gasoline

Hydrogen is abundant stored in H2O, hydrocarbons & other organic matter

Distillation: Involves reduction of volume of radioactive waste in solid

Radioactive waste is treated, in chronological order Incineration, evaporation and compaction to avoid contamination

​

Radioactive waste remain forever buried

Possibilities of leakage and contamination into the ground water or into the ocean

Other physical methods: cutting, decontamination, sedimentation, land fill

Recycle, Reuse, Repurpose,
Refuel & Renew (5R)

Incineration Distillation
EvaporationDumping

Highly expensive due to its high-energy requirement

Requires gas-filtering systems to control radioactive discharges.

Highly expensive due to its high-energy requirement

Evaporation in organic salts leads to explosion

Releasing CO2, H2O, S, and HC1 as by-product