This document provides an overview of electrochemical remediation technologies for polluted soils, sediments, and groundwater. It is divided into 9 sections that cover topics such as the remediation of heavy metals, organic pollutants, and mixed contaminants. It also discusses electrokinetic barriers, integrated/coupled technologies, mathematical modeling, economic and regulatory considerations, and field applications/performance assessment. The document contains 33 chapters written by over 70 international experts and provides a comprehensive reference for electrochemical remediation.
In India around 147 million hectares (Mha) of land is under degradation, this includes 94 Mha from water erosion, 16 Mha from acidification, 14 Mha from flooding, 9 Mha from wind erosion, 6 Mha from salinity, and 7 Mha from a combination of factors. Even though The total land area of India is just 2.4% of the world’s land area , it ranks second in the world in farming. Agriculture employs almost 50% of the total workforce in India. So there is an increased need for monitoring and researching the various facets of land degradation. Electrokinetics is defined as the physicochemical transport of charge, action of charged particles and effects of applied electric potentials on formation and fluid transport in porous media. The utilization of electrokinetic in geotechnical engineering for dewatering, consolidation and stabilization of low permeability and to transport certain chemical species in an electrolyte system had opened new opportunities for application in geo environmental engineering. Approaching anode is one of the enhancement techniques in electrokinetic soil remediation. This technique is reported to give promising migration for heavy metals under shorter treatment time and at lower cost in comparison to normal fixed anode system. In the present study, the effectiveness of fixed anode and approaching anode techniques in electrokinetic soil remediation for lead migration under different types of wetting agents (0.01M NaNO3 and 0.1M citric acid) was investigated. Key Words: Acidification , Failure, Land Degradation, Electrokinetics
Electrochemical study of anatase TiO2 in aqueous sodium-ion electrolytesRatnakaram Venkata Nadh
In this paper, a basic electro-analytical study on the behavior of anatase TiO2 in aqueous NaOH has been presented using cyclic voltammetry technique (CV). The study has explored the possibility of using TiO2 as anode material for ARSBs in presence of 5 M NaOH aqueous electrolyte. CV profiles show that anatase TiO2 exhibits reversible sodium ion insertion/de-insertion reactions. CV studies of TiO2 anode in aqueous sodium electrolytes at different scan rate shows that the Na+ ion insertion reaction at the electrode is diffusion controlled with a resistive behavior. Proton insertion from aqueous sodium electrolytes into TiO2 cannot be ruled out. To confirm the ion inserted and de-inserted, CV studies are done at different concentration of NaOH and it is found that at lower concentrations of NaOH, proton insertion process competes with Na+ ion insertion process and as the concentration increases, the Na+ ion insertion process becomes the predominant electrode reaction making it suitable anode materials for aqueous sodium batteries in 5 M NaOH.
Photocatalysis has now become an emerging scientific discipline due to its interdisciplinary nature. The wide range of research groups is now working on different aspects of photocatalysis worldwide. It is one of the technology the world looking forward to address environmental as well as energy related issues. Hence we can call it as a technology for the future or a dream technology! We need to overcome too many hurdles to implement this technology in real life. Like any other discipline there is a lot of misunderstanding/ misconceptions in photocatalysis.
Most frequently cited article in the field of photocatalysis is by Fujishima and Honda published in 1972 in nature and it has been cited by the photocatalytic community as an origin of photocatalysis. This aspect is not true at all. This article cannot be the origin of photocatalysis. This article only promoted photocatalytic studies. The author itself, actually, started a research career in the “boom” of photocatalytic studies initiated by this article.
This small presentation aims to deliver some misconceptions like above in photocatalysis. The entire presentation is based on different personal commentaries written by Jean Mary Hermann and Bunsho Ohtani. Some recent articles relevant to the topic are collected by the speaker itself and put it in one platform.
Carbon-cuprous oxide composite nanoparticles
were chemically deposited on surface of thin glass tubes of spent
energy saving lamps for solar heat collection. Carbon was
obtained from fly ash of heavy oil incomplete combustion in
electric power stations. Impurities in the carbon were removed by
leaching with mineral acids. The mineral free-carbon was then
wet ground to have a submicron size. After filtration, it was
reacted with concentrated sulfuric/fuming nitric acid mixture on
cold for 3-4 days. Potassium chlorate was then added drop wise on
hot conditions to a carbon slurry followed by filtration.
Nanocarbon sample was mixed with 5% by weight PVA to help
adhesion to the glass surface. Carbon so deposited was doped with
copper nitrate solution. After dryness, the carbon/copper nitrate
film was dipped in hydrazine hydrate to form cuprous oxide -
carbon composite, It was then roasted at 380-400 °C A heat
collector testing assembly was constructed of 5 glass coils
connected in series with a total surface area of 1250 cm2
. Heat
collection was estimated by water flowing in the glass coils that
are coated with the carbon/copper film,. Parameters affecting the
solar collection efficiency such as time of exposure and mass flow
rate of the water were studied. Results revealed that the prepared
glass coil has proven successful energy collector for solar heat.
In India around 147 million hectares (Mha) of land is under degradation, this includes 94 Mha from water erosion, 16 Mha from acidification, 14 Mha from flooding, 9 Mha from wind erosion, 6 Mha from salinity, and 7 Mha from a combination of factors. Even though The total land area of India is just 2.4% of the world’s land area , it ranks second in the world in farming. Agriculture employs almost 50% of the total workforce in India. So there is an increased need for monitoring and researching the various facets of land degradation. Electrokinetics is defined as the physicochemical transport of charge, action of charged particles and effects of applied electric potentials on formation and fluid transport in porous media. The utilization of electrokinetic in geotechnical engineering for dewatering, consolidation and stabilization of low permeability and to transport certain chemical species in an electrolyte system had opened new opportunities for application in geo environmental engineering. Approaching anode is one of the enhancement techniques in electrokinetic soil remediation. This technique is reported to give promising migration for heavy metals under shorter treatment time and at lower cost in comparison to normal fixed anode system. In the present study, the effectiveness of fixed anode and approaching anode techniques in electrokinetic soil remediation for lead migration under different types of wetting agents (0.01M NaNO3 and 0.1M citric acid) was investigated. Key Words: Acidification , Failure, Land Degradation, Electrokinetics
Electrochemical study of anatase TiO2 in aqueous sodium-ion electrolytesRatnakaram Venkata Nadh
In this paper, a basic electro-analytical study on the behavior of anatase TiO2 in aqueous NaOH has been presented using cyclic voltammetry technique (CV). The study has explored the possibility of using TiO2 as anode material for ARSBs in presence of 5 M NaOH aqueous electrolyte. CV profiles show that anatase TiO2 exhibits reversible sodium ion insertion/de-insertion reactions. CV studies of TiO2 anode in aqueous sodium electrolytes at different scan rate shows that the Na+ ion insertion reaction at the electrode is diffusion controlled with a resistive behavior. Proton insertion from aqueous sodium electrolytes into TiO2 cannot be ruled out. To confirm the ion inserted and de-inserted, CV studies are done at different concentration of NaOH and it is found that at lower concentrations of NaOH, proton insertion process competes with Na+ ion insertion process and as the concentration increases, the Na+ ion insertion process becomes the predominant electrode reaction making it suitable anode materials for aqueous sodium batteries in 5 M NaOH.
Photocatalysis has now become an emerging scientific discipline due to its interdisciplinary nature. The wide range of research groups is now working on different aspects of photocatalysis worldwide. It is one of the technology the world looking forward to address environmental as well as energy related issues. Hence we can call it as a technology for the future or a dream technology! We need to overcome too many hurdles to implement this technology in real life. Like any other discipline there is a lot of misunderstanding/ misconceptions in photocatalysis.
Most frequently cited article in the field of photocatalysis is by Fujishima and Honda published in 1972 in nature and it has been cited by the photocatalytic community as an origin of photocatalysis. This aspect is not true at all. This article cannot be the origin of photocatalysis. This article only promoted photocatalytic studies. The author itself, actually, started a research career in the “boom” of photocatalytic studies initiated by this article.
This small presentation aims to deliver some misconceptions like above in photocatalysis. The entire presentation is based on different personal commentaries written by Jean Mary Hermann and Bunsho Ohtani. Some recent articles relevant to the topic are collected by the speaker itself and put it in one platform.
Carbon-cuprous oxide composite nanoparticles
were chemically deposited on surface of thin glass tubes of spent
energy saving lamps for solar heat collection. Carbon was
obtained from fly ash of heavy oil incomplete combustion in
electric power stations. Impurities in the carbon were removed by
leaching with mineral acids. The mineral free-carbon was then
wet ground to have a submicron size. After filtration, it was
reacted with concentrated sulfuric/fuming nitric acid mixture on
cold for 3-4 days. Potassium chlorate was then added drop wise on
hot conditions to a carbon slurry followed by filtration.
Nanocarbon sample was mixed with 5% by weight PVA to help
adhesion to the glass surface. Carbon so deposited was doped with
copper nitrate solution. After dryness, the carbon/copper nitrate
film was dipped in hydrazine hydrate to form cuprous oxide -
carbon composite, It was then roasted at 380-400 °C A heat
collector testing assembly was constructed of 5 glass coils
connected in series with a total surface area of 1250 cm2
. Heat
collection was estimated by water flowing in the glass coils that
are coated with the carbon/copper film,. Parameters affecting the
solar collection efficiency such as time of exposure and mass flow
rate of the water were studied. Results revealed that the prepared
glass coil has proven successful energy collector for solar heat.
Biosorption of Copper (II) Ions by Eclipta Alba Leaf Powder from Aqueous Solu...ijtsrd
The removal of heavy metals from industrial wastewater is of great concern as heavy metals are non-biodegradable, toxic elements that cause serious health problems if disposed of in the surrounding environment. The present study, Karisalangkani (Eclipta Alba) leaves were used for the adsorption of heavy metals like copper (Cu (II)) ions. The bio sorbent was characterized using SEM and BET analysis. The bio sorption experiments are conducted through batch system. The operating parameters studied were initial metal ion concentration, adsorbent dosage, initial solution pH, contact time and effect of temperature Adsorption equilibrium is achieved in 30 min and the adsorption kinetics of Cu (II) is found to follow a pseudo-second-order kinetic model. Equilibrium data for Cu (II) adsorption are fitted well by Langmuir isotherm model. The maximum adsorption capacity for Cu (II) ions is estimated to be 9.2 mgg at 25 °C. The experimental result shows that the materials have good potential to remove heavy metals from effluent and good potential as an alternate low cost adsorbent. Due to their outstanding adsorption capacities, Eclipta Alba is excellent sorbents for the removal of copper (II) ions. B. Kavitha | R. Arunadevi"Biosorption of Copper (II) Ions by Eclipta Alba Leaf Powder from Aqueous Solutions" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-5 , August 2018, URL: http://www.ijtsrd.com/papers/ijtsrd17156.pdf http://www.ijtsrd.com/chemistry/environmental-chemistry/17156/biosorption-of-copper-ii-ions-by-eclipta-alba-leaf-powder-from-aqueous-solutions/b-kavitha
Visible light solar photocatalytic degradation of pulp and paper wastewater u...eSAT Journals
Abstract
With the growing number of industries there are large volumes of wastewater generated every day. Pulp and paper mills are highly polluting as they release effluents containing organic pollutants, and high levels of Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD). Even though well-established processes exist to treat these effluents, there are only a few processes which are energy efficient. Conventional treatment methods are not effective for the degradation of toxic organic pollutants, hence other treatment techniques are necessary. One of the recent developments in this field is the Advanced Oxidation Process (AOP). Solar photocatalysis is a type of AOP which utilises UV light to activate semiconductor photocatalyst in order to produce highly reactive radical species. TiO2 is a widely used catalyst for this purpose, to oxidise or reduce the organic pollutants in industrial wastewater. However, photocatalysis using visible light has been receiving increased attention hence, modification of TiO2 is necessary for its enhanced response to visible light. There are many methods for modifying TiO2, such as doping and photo-sensitisation. This study focusses on the modification of TiO2 using the method of dye-sensitisation (photo-sensitisation) with the dyes rhodamine B and methylene blue. Solar photocatalytic experiments were carried out for the degradation of pulp and paper wastewater, at different conditions like varying catalyst loading (500mg, 600mg, 750mg and 1000mg of catalyst for 300ml of aqueous wastewater) and effluent concentration (20ml, 25ml, 30ml and 35ml of wastewater). Preliminary tests were done to determine the best conditions for photocatalytic degradation, and these were applied for final tests. Keywords - Solar Photocatalysis, Visible Light, Dye Sensitisation, Pulp and paper, Methylene blue, Rhodamine B, TiO2 catalyst.
Removal of heavy metals from wastewater by carbon nanotubesAshish Gadhave
Advent of nanotechnology has introduced us with new generation of adsorbents such as carbon nanotubes (CNTs)
which have aroused widespread attention due to their outstanding ability for the removal of various inorganic and
organic pollutants from large volumes of water. This article reviews the practical feasibility of various kinds of raw
and surface modified carbon nanotubes for adsorption of heavy metal ions from wastewater. Further, properties of
CNTs (adsorption sites), characterization of CNTs (pore volume, BET surface area, surface total acidity, surface
total basicity) and solution properties (ionic strength, effect of pH) are explained very well. The adsorption
mechanisms are mainly attributable to chemical interactions between metal ions and surface functional groups of the CNTs. The adsorption capacity increases to greater extend after functionalization i.e. surface oxidation of CNTs. Future work on developing cost effective ways of production of CNTs and analyzing its toxicity are recommended.
Extraction of Heavy Metals From Industrial Waste WaterHashim Khan
This was my topic of research during Bachelors. I made this presentation to give a brief overview of what apparatus i used and the methodologies of my experimentation.
Sunlight-driven water-splitting using two dimensional carbon based semiconduc...Pawan Kumar
The overwhelming challenge of depleting fossil fuels and anthropogenic carbon emissions has driven research
into alternative clean sources of energy. To achieve the goal of a carbon neutral economy, the harvesting of
sunlight by using photocatalysts to split water into hydrogen and oxygen is an expedient approach to fulfill
the energy demand in a sustainable way along with reducing the emission of greenhouse gases. Even though
the past few decades have witnessed intensive research into inorganic semiconductor photocatalysts, their
quantum efficiencies for hydrogen production from visible photons remain too low for the large scale
deployment of this technology. Visible light absorption and efficient charge separation are two key necessary
conditions for achieving the scalable production of hydrogen from water. Two-dimensional carbon based
nanoscale materials such as graphene oxide, reduced graphene oxide, carbon nitride, modified 2D carbon
frameworks and their composites have emerged as potential photocatalysts due to their astonishing
properties such as superior charge transport, tunable energy levels and bandgaps, visible light absorption,
high surface area, easy processability, quantum confinement effects, and high photocatalytic quantum yields.
The feasibility of structural and chemical modification to optimize visible light absorption and charge
separation makes carbonaceous semiconductors promising candidates to convert solar energy into chemical
energy. In the present review, we have summarized the recent advances in 2D carbonaceous photocatalysts
with respect to physicochemical and photochemical tuning for solar light mediated hydrogen evolution
On what we know and what we don’t know about the photocatalytic conversion of...Hariprasad Narayanan
Reduction of carbon dioxide into value added fuels and chemicals has been an interested field of research both in terms of energy as well as in environmental point of view. In photocatalytic reduction, in principle, the material harnesses the natural sun and atmospheric carbon dioxide in a sustainable pathway and convert it into chemicals and fuels, which requires a series of electron and proton transfer reactions, a style similar to the natural photosynthesis. Only the fruition of the technology, even in research laboratory scale is still a challenge due to the ‘n’ number of hurdles associated with the procedure. The mechanistic aspects are yet not readable or the current knowledge is not sufficient to explain the exact reaction mechanism. Amazingly, no arguments or controversies going on these issues among the scientific community. Out of all ‘n’ number of hurdles, here we are debating the mystery behind the mechanistic aspects of CO2 reduction.
degradation of pollution and photocatalysisPraveen Vaidya
The presentation deals with the use of conduction of photocatalytic reaction using the transition metal doped transparent semiconducting thinfilms. The precursor to film is prepared by the SILAR method, which is a chemical method.
The threat of global warming is high due to the extensive use of fossil fuels.Using non-renewable resources is a viable solution. Sunlight can be converted in two ways - into electrical energy and into chemical energy. Water splitting and CO2 are two important methods which can be used in solar cells.
Multiple adsorption of heavy metal ions in aqueous solution using activated c...eSAT Journals
Abstract
Batch adsorption of different heavy metal ions (Nickel, Copper, Zinc, Lead, Cadmium and Chromium) in aqueous solution using
activated carbon from Nigerian bamboo was studied. The bamboo was cut, washed and dried. It was carbonized between 3000C -
4500C, and activated at 8000C using nitric acid. The bulk density, iodine number, Benzene adsorption, methylene adsorption, and
ash content of the activated carbon produced compared well with commercial carbons. Multiple adsorption of these metals in
same aqueous solution using bamboo carbon showed that adsorption capacity is in the order Pb>Cd>Cu>Zn>Ni>Cr which
showed that these metal ions can be adsorbed selectively by Nigerian bamboo activated carbon. The order of adsorption is related
to the maximum adsorption of lead, cadmium, copper on bamboo was found to be in the order of ionic radius of the heavy metals
used. Therefore this study demonstrates that bamboo can serve as a good source of activated carbon with multiple metal ions –
removing potentials and may serve as a better replacement for commercial activated carbons in applications that warrant their
use. However, it will also contribute to the search for less expensive adsorbents and their utilization possibilities for the
elimination of heavy metal ions from industrial waste water.
Key Words: multiple adsorption, heavy metals, Nigerian bamboo, Activated Carbon,
Molecular Mean Field Theory of ions in Bulk and ChannelsBob Eisenberg
Life and most of chemistry occurs in ionic solutions, but ionic solutions have only recently been recognized as the complex fluids that they are. The molecular view shows ions interacting with surrounding water and nearby ions. Everything is correlated in a complex way because ions and water have diameters comparable to their interaction length. The molecular scale shows only a small part of the correlation enforced by electrodynamics. Current defined as Maxwell did to include the ethereal current is exactly conserved, and therefore correlated, over all scales reaching to macroscopic boundary conditions some 10^9× larger than atoms crucial in batteries and nerve cells.
Jinn Liang Liu and I have built a molecular field theory PNPB Poisson Nernst Planck Bikerman that deals with water as molecules and describes local interactions with a steric potential that depends on the volume fraction of molecules and voids between them. The correlations of electrodynamics are described by a fourth-order differential operator that gives (as outputs) ion-ion and ion-water correlations; the dielectric response (permittivity) of ionic solutions; and the polarization of water molecules, all using a single correlation length parameter. The theory fits experimental data on activity and differential capacitance in ionic solutions of varying composition and content, including mixtures. Potassium channels, Gramicidin, L-type calcium channels, and the Na/Ca transporter are computed in three dimensions from structures in the Protein Data Bank.
Numerical analysis faces challenges
Geometric singularities of molecular surfaces
strong electric fields (100 mV/nm) and resulting exponential nonlinearities, and the
enormous concentrations (> 10 M) often found where ions are important, for example, near electrodes in batteries, in ion channels, and in active sites of proteins.
Wide ranging concentrations of Ca^(2+) in (> 10M) and near (10^(-2) to 10^(-8)M) almost every protein in biological cells make matters worse.
Challenges have been overcome using methods developed over many decades by the large community that works on the computational electronics of semiconductors.
I went to Bowdoin college to give a chemistry seminar on my graduate research as well as career advice from my experience working in industry. This powerpoint also includes many hidden slides that I recycle depending on the talk I'm giving.
Biosorption of Copper (II) Ions by Eclipta Alba Leaf Powder from Aqueous Solu...ijtsrd
The removal of heavy metals from industrial wastewater is of great concern as heavy metals are non-biodegradable, toxic elements that cause serious health problems if disposed of in the surrounding environment. The present study, Karisalangkani (Eclipta Alba) leaves were used for the adsorption of heavy metals like copper (Cu (II)) ions. The bio sorbent was characterized using SEM and BET analysis. The bio sorption experiments are conducted through batch system. The operating parameters studied were initial metal ion concentration, adsorbent dosage, initial solution pH, contact time and effect of temperature Adsorption equilibrium is achieved in 30 min and the adsorption kinetics of Cu (II) is found to follow a pseudo-second-order kinetic model. Equilibrium data for Cu (II) adsorption are fitted well by Langmuir isotherm model. The maximum adsorption capacity for Cu (II) ions is estimated to be 9.2 mgg at 25 °C. The experimental result shows that the materials have good potential to remove heavy metals from effluent and good potential as an alternate low cost adsorbent. Due to their outstanding adsorption capacities, Eclipta Alba is excellent sorbents for the removal of copper (II) ions. B. Kavitha | R. Arunadevi"Biosorption of Copper (II) Ions by Eclipta Alba Leaf Powder from Aqueous Solutions" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-5 , August 2018, URL: http://www.ijtsrd.com/papers/ijtsrd17156.pdf http://www.ijtsrd.com/chemistry/environmental-chemistry/17156/biosorption-of-copper-ii-ions-by-eclipta-alba-leaf-powder-from-aqueous-solutions/b-kavitha
Visible light solar photocatalytic degradation of pulp and paper wastewater u...eSAT Journals
Abstract
With the growing number of industries there are large volumes of wastewater generated every day. Pulp and paper mills are highly polluting as they release effluents containing organic pollutants, and high levels of Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD). Even though well-established processes exist to treat these effluents, there are only a few processes which are energy efficient. Conventional treatment methods are not effective for the degradation of toxic organic pollutants, hence other treatment techniques are necessary. One of the recent developments in this field is the Advanced Oxidation Process (AOP). Solar photocatalysis is a type of AOP which utilises UV light to activate semiconductor photocatalyst in order to produce highly reactive radical species. TiO2 is a widely used catalyst for this purpose, to oxidise or reduce the organic pollutants in industrial wastewater. However, photocatalysis using visible light has been receiving increased attention hence, modification of TiO2 is necessary for its enhanced response to visible light. There are many methods for modifying TiO2, such as doping and photo-sensitisation. This study focusses on the modification of TiO2 using the method of dye-sensitisation (photo-sensitisation) with the dyes rhodamine B and methylene blue. Solar photocatalytic experiments were carried out for the degradation of pulp and paper wastewater, at different conditions like varying catalyst loading (500mg, 600mg, 750mg and 1000mg of catalyst for 300ml of aqueous wastewater) and effluent concentration (20ml, 25ml, 30ml and 35ml of wastewater). Preliminary tests were done to determine the best conditions for photocatalytic degradation, and these were applied for final tests. Keywords - Solar Photocatalysis, Visible Light, Dye Sensitisation, Pulp and paper, Methylene blue, Rhodamine B, TiO2 catalyst.
Removal of heavy metals from wastewater by carbon nanotubesAshish Gadhave
Advent of nanotechnology has introduced us with new generation of adsorbents such as carbon nanotubes (CNTs)
which have aroused widespread attention due to their outstanding ability for the removal of various inorganic and
organic pollutants from large volumes of water. This article reviews the practical feasibility of various kinds of raw
and surface modified carbon nanotubes for adsorption of heavy metal ions from wastewater. Further, properties of
CNTs (adsorption sites), characterization of CNTs (pore volume, BET surface area, surface total acidity, surface
total basicity) and solution properties (ionic strength, effect of pH) are explained very well. The adsorption
mechanisms are mainly attributable to chemical interactions between metal ions and surface functional groups of the CNTs. The adsorption capacity increases to greater extend after functionalization i.e. surface oxidation of CNTs. Future work on developing cost effective ways of production of CNTs and analyzing its toxicity are recommended.
Extraction of Heavy Metals From Industrial Waste WaterHashim Khan
This was my topic of research during Bachelors. I made this presentation to give a brief overview of what apparatus i used and the methodologies of my experimentation.
Sunlight-driven water-splitting using two dimensional carbon based semiconduc...Pawan Kumar
The overwhelming challenge of depleting fossil fuels and anthropogenic carbon emissions has driven research
into alternative clean sources of energy. To achieve the goal of a carbon neutral economy, the harvesting of
sunlight by using photocatalysts to split water into hydrogen and oxygen is an expedient approach to fulfill
the energy demand in a sustainable way along with reducing the emission of greenhouse gases. Even though
the past few decades have witnessed intensive research into inorganic semiconductor photocatalysts, their
quantum efficiencies for hydrogen production from visible photons remain too low for the large scale
deployment of this technology. Visible light absorption and efficient charge separation are two key necessary
conditions for achieving the scalable production of hydrogen from water. Two-dimensional carbon based
nanoscale materials such as graphene oxide, reduced graphene oxide, carbon nitride, modified 2D carbon
frameworks and their composites have emerged as potential photocatalysts due to their astonishing
properties such as superior charge transport, tunable energy levels and bandgaps, visible light absorption,
high surface area, easy processability, quantum confinement effects, and high photocatalytic quantum yields.
The feasibility of structural and chemical modification to optimize visible light absorption and charge
separation makes carbonaceous semiconductors promising candidates to convert solar energy into chemical
energy. In the present review, we have summarized the recent advances in 2D carbonaceous photocatalysts
with respect to physicochemical and photochemical tuning for solar light mediated hydrogen evolution
On what we know and what we don’t know about the photocatalytic conversion of...Hariprasad Narayanan
Reduction of carbon dioxide into value added fuels and chemicals has been an interested field of research both in terms of energy as well as in environmental point of view. In photocatalytic reduction, in principle, the material harnesses the natural sun and atmospheric carbon dioxide in a sustainable pathway and convert it into chemicals and fuels, which requires a series of electron and proton transfer reactions, a style similar to the natural photosynthesis. Only the fruition of the technology, even in research laboratory scale is still a challenge due to the ‘n’ number of hurdles associated with the procedure. The mechanistic aspects are yet not readable or the current knowledge is not sufficient to explain the exact reaction mechanism. Amazingly, no arguments or controversies going on these issues among the scientific community. Out of all ‘n’ number of hurdles, here we are debating the mystery behind the mechanistic aspects of CO2 reduction.
degradation of pollution and photocatalysisPraveen Vaidya
The presentation deals with the use of conduction of photocatalytic reaction using the transition metal doped transparent semiconducting thinfilms. The precursor to film is prepared by the SILAR method, which is a chemical method.
The threat of global warming is high due to the extensive use of fossil fuels.Using non-renewable resources is a viable solution. Sunlight can be converted in two ways - into electrical energy and into chemical energy. Water splitting and CO2 are two important methods which can be used in solar cells.
Multiple adsorption of heavy metal ions in aqueous solution using activated c...eSAT Journals
Abstract
Batch adsorption of different heavy metal ions (Nickel, Copper, Zinc, Lead, Cadmium and Chromium) in aqueous solution using
activated carbon from Nigerian bamboo was studied. The bamboo was cut, washed and dried. It was carbonized between 3000C -
4500C, and activated at 8000C using nitric acid. The bulk density, iodine number, Benzene adsorption, methylene adsorption, and
ash content of the activated carbon produced compared well with commercial carbons. Multiple adsorption of these metals in
same aqueous solution using bamboo carbon showed that adsorption capacity is in the order Pb>Cd>Cu>Zn>Ni>Cr which
showed that these metal ions can be adsorbed selectively by Nigerian bamboo activated carbon. The order of adsorption is related
to the maximum adsorption of lead, cadmium, copper on bamboo was found to be in the order of ionic radius of the heavy metals
used. Therefore this study demonstrates that bamboo can serve as a good source of activated carbon with multiple metal ions –
removing potentials and may serve as a better replacement for commercial activated carbons in applications that warrant their
use. However, it will also contribute to the search for less expensive adsorbents and their utilization possibilities for the
elimination of heavy metal ions from industrial waste water.
Key Words: multiple adsorption, heavy metals, Nigerian bamboo, Activated Carbon,
Molecular Mean Field Theory of ions in Bulk and ChannelsBob Eisenberg
Life and most of chemistry occurs in ionic solutions, but ionic solutions have only recently been recognized as the complex fluids that they are. The molecular view shows ions interacting with surrounding water and nearby ions. Everything is correlated in a complex way because ions and water have diameters comparable to their interaction length. The molecular scale shows only a small part of the correlation enforced by electrodynamics. Current defined as Maxwell did to include the ethereal current is exactly conserved, and therefore correlated, over all scales reaching to macroscopic boundary conditions some 10^9× larger than atoms crucial in batteries and nerve cells.
Jinn Liang Liu and I have built a molecular field theory PNPB Poisson Nernst Planck Bikerman that deals with water as molecules and describes local interactions with a steric potential that depends on the volume fraction of molecules and voids between them. The correlations of electrodynamics are described by a fourth-order differential operator that gives (as outputs) ion-ion and ion-water correlations; the dielectric response (permittivity) of ionic solutions; and the polarization of water molecules, all using a single correlation length parameter. The theory fits experimental data on activity and differential capacitance in ionic solutions of varying composition and content, including mixtures. Potassium channels, Gramicidin, L-type calcium channels, and the Na/Ca transporter are computed in three dimensions from structures in the Protein Data Bank.
Numerical analysis faces challenges
Geometric singularities of molecular surfaces
strong electric fields (100 mV/nm) and resulting exponential nonlinearities, and the
enormous concentrations (> 10 M) often found where ions are important, for example, near electrodes in batteries, in ion channels, and in active sites of proteins.
Wide ranging concentrations of Ca^(2+) in (> 10M) and near (10^(-2) to 10^(-8)M) almost every protein in biological cells make matters worse.
Challenges have been overcome using methods developed over many decades by the large community that works on the computational electronics of semiconductors.
I went to Bowdoin college to give a chemistry seminar on my graduate research as well as career advice from my experience working in industry. This powerpoint also includes many hidden slides that I recycle depending on the talk I'm giving.
I am attaching the list of departmental electives offered by the Department of Chemistry for The Autumn semester 2019 at IIT Kharagpur for two years MSc Students
Bicrystalline Titania Photocatalyst for Reduction of CO2 to Solar FuelsA'Lester Allen
Degussa P25, a mixture of anatase and rutile crystal structures, is the most commonly used precursor to form the photoactive layer in solar cells; however, the photocatalytic activity of rutile is inferior to brookite. This presentation discusses the enhancement in photocatalytic activity of an antase brookite mixture.
Table of Contents for PNAS August 19, 2014 vol. 111 no. 33.
# JOURNAL NAME: Proceedings Of The National Academy Of Sciences Of The United States Of America
# ABBREVIATION: P NATL ACAD SCI USA
# 2013 JCR IMPACT FACTOR: 9.809
Electrochemical Behavior of L-Tyrosine at Poly (Dicyclomine Hydrochloride) Fi...paperpublications3
Abstract: An electrochemical method for the determination of L-Tyrosine (LTY) using a dicyclomine hydrochloride (DICY) polymer film modified carbon paste electrode. The surface morphology of poly (DICY) modified carbon paste electrode was characterized by SEM. The modified electrode showed excellent electro catalytic activity towards the oxidation of LTY in 0.1 M phosphate buffer solution of pH 6.5. The effect of pH, concentration and scan rate were studied at the bare carbon paste electrode and poly (DICY) modified carbon paste electrode were investigated. Increase of LTY concentration shows linear increase in oxidation peak current. The linear relationship was obtained between the anodic peak current (Ipa) and concentration LTY in range 2×10-5 M to 1×10-3 M with correlation coefficient of 0.9984. The low detection limit (LOD) and low quantification limit (LOQ) of LTY were detected. The cyclic voltammetric studies indicated that the oxidation of LTY at the modified electrode surface was irreversible; adsorption controlled and undergoes a one electron transfer process at the poly (DICY) film modified carbon paste electrode. The modified electrode showed high sensitivity, detection limit, high reproducibility, easy preparation and regeneration of the electrode surface.
1. Electrochemical Remediation Technologies
for polluted soils, sediments and groundwater
Reddy, K.R. and Cameselle, C.
SECTIONS
I. INTRODUCTION AND BASIC PRINCIPLES
II. REMEDIATION OF HEAVY METALS AND OTHER
INORGANIC POLLUTANTS
III. REMEDIATION OF ORGANIC POLLUTANTS
IV. REMEDIATION OF MIXED CONTAMINANTS
V. ELECTROKINETIC BARRIERS
VI. INTEGRATED (COUPLED) TECHNOLOGIES
VII. MATHEMATICAL MODELING
VIII. ECONOMIC AND REGULATORY
CONSIDERATIONS
IX. FIELD APPLICATIONS AND PERFORMANCE
ASSESSMENT
2. CONTRIBUTORS
Christopher J. Athmer (USA) Reinout Lageman (The Netherlands)
Kitae Baek (Korea) You-Jin Lee (Korea)
Dave Bowman (USA) Keun-Young Lee (Korea)
Claudio Cameselle (Spain) MyungHo Lee (Korea) Krishna R. Reddy (USA)
Penny Carter (United Kingdom) M.C. Lobo Bedmar(Spain) Alexandra B. Ribeiro (Portugal)
Ha Ik Chung (Korea) Svenja T. Lohner (Germany) José Miguel Rodríguez-Maroto (Spain)
Andrew Cundy (United Kingdom) Xiaohua Lu (China) B. Schrammel (Austria)
Giorgia De Gioannis (Italy) Rod Lynch (United Kingdom) Mika Sillanpaa (Finland)
Andrea Diamant (Austria) Charles P. Marsh (USA) Gregory J. Smith (USA)
Falk Doering (Germany) M.J. Martínez-Iñigo (Spain) R. Sri Ranjan (Canada)
Maria Elektorowicz (Canada) Eduardo P. Mateus (Portugal) Andreas Tiehm (Germany)
David Faulkner (United Kingdom) Sean Morefield (USA) M. Unterberger (Austria)
Henrik K. Hansen (Chile) Aldo Muntoni (Italy) Carlos Vereda-Alonso (Spain)
Anne Hansen (United Kingdom) Anshy Oonnittan (Finland) Chih-Huang Weng (Taiwan)
Sa V. Ho (USA) Lisbeth M. Ottosen (Denmark) W. Wesner (Austria)
Laurence Hopkinson (United Kingdom) Prof. Sibel Pamukcu (USA) Lukas Y. Wick (Germany)
Simon A. Jackman (United Kingdom) Randy A. Parker (USA) J. Kenneth Wittle (USA)
Pernille E. Jensen (Denmark) A. Pérez-Sanz (Spain) Jung-Seok Yang (Korea)
Ahmet Karagunduz (Turkey) A. Plaza-Benito (Spain) Gordon C. C. Yang (Taiwan)
David A. Kessler (USA) Alessandra Polettini (Italy) Ji-Won Yang (Korea)
Kyoung-Woong Kim (Korea) Ross Pollock (United Kingdom) Albert T. Yeung (China)
Soon-Oh Kim (Korea) Raffaella Pomi (Italy) Songhu Yuan (China)
Vladimir A. Korolev (Russia) Wiebe Pool (The Netherlands) Lawrence M. Zanko (USA)
3. Table of Contents
SECTION I: INTRODUCTION AND BASIC PRINCIPLES
Chapter 1. Overview of electrochemical remediation technologies
Krishna R. Reddy, Claudio Cameselle
Chapter 2. Electrochemical Transport and Transformations
Sibel Pamukcu
Chapter 3. Geochemical Processes Affecting Electrochemical Remediation
Albert T. Yeung
4. Table of Contents
SECTION II: REMEDIATION OF HEAVY METALS AND OTHER INORGANIC POLLUTANTS
Chapter 4. Electrokinetic removal of heavy metals
Lisbeth M. Ottosen, Henrik K. Hansen, Pernille E. Jensen
Chapter 5. Electrokinetic Removal of Radionuclides
Korolev V.A.
Chapter 6. Electrokinetic Removal of Nitrate and Fluoride
Kitae Baek, Jung-Seok Yang
Chapter 7. Electrokinetic Treatment of Contaminated Marine Sediments
Giorgia De Gioannis, Aldo Muntoni, Alessandra Polettini, Raffaella Pomi
Chapter 8. Electrokinetic Stabilization of Chromium (VI) Contaminated Soils
Laurence Hopkinson, Andrew Cundy, David Faulkner, Anne Hansen, Ross Pollock
5. Table of Contents
SECTION III: REMEDIATION OF ORGANIC POLLUTANTS
Chapter 9. Electrokinetic Removal of PAHs
Ji-Won Yang You-Jin Lee
Chapter 10. Electrokinetic removal of chlorinated organic compounds
Xiaohua Lu, Songhu Yuan
Chapter 11. Elcetrokinetic transport of chlorinated organic pesticides
Ahmet Karagunduz
Chapter 12. Electrokinetic removal of herbicides from soils
Alexandra B. Ribeiro, Eduardo P. Mateus
Chapter 13. Electrokinetic Removal of Energetic Compounds
David A. Kessler, Charles P. Marsh, Sean Morefield
6. Table of Contents
SECTION IV: REMEDIATION OF MIXED CONTAMINANTS
Chapter 14. Electrokinetic Remediation of Mixed Metal Contaminants
Kyoung-Woong Kim, Keun-Young Lee, Soon-Oh Kim
Chapter 15. Electrokinetic Remediation of Mixed Metals and Organic Contaminants
Maria Elektorowicz
SECTION V: ELECTROKINETIC BARRIERS
Chapter 16. Electrokinetic barriers for preventing groundwater pollution
Rod Lynch
Chapter 17. Electrokinetic Biofences
Reinout Lageman, Wiebe Pool
7. Table of Contents
SECTION VI: INTEGRATED (COUPLED) TECHNOLOGIES
Chapter 18. Coupling Electrokinetics to the Bioremediation of Organic Contaminants: A
Microbial Perspective on Fundamental Interactions
Lukas Y. Wick
Chapter 19. Coupled electrokinetic – bioremediation: Applied Aspects
Svenja T. Lohner, Andreas Tiehm, Simon A. Jackman, Penny Carter
Chapter 20. Influence of Coupled Electrokinetic-Phytoremediation on soil remediation.
M.C. Lobo Bedmar, A. Pérez-Sanz, M.J. Martínez-Iñigo, A. Plaza Benito
Chapter 21. Coupled electrokinetic-chemical oxidation/reduction
Gordon C. C. Yang
Chapter 22. Electro Synthesis of Oxidants and Their Electrokinetic Distribution
Wolfgang Wesner, Andrea Diamant, B. Schrammel, M. Unterberger
Chapter 23. Coupled Electrokinetic-Permeable Reactive Barriers
Chih-Huang Weng
Chapter 24. Coupled Electrokinetics – Thermal Desorption
Gregory J. Smith
8. Table of Contents
SECTION VII: MATHEMATICAL MODELING
Chapter 25. Electrokinetic Modeling of Heavy Metals
José Miguel Rodríguez-Maroto, Carlos Vereda-Alonso
Chapter 26. Electrokinetic Barriers: Modeling and Validation
R. Sri Ranjan
SECTION VIII: ECONOMIC AND REGULATORY CONSIDERATIONS
Chapter 27. Cost Estimates for Electrokinetic Remediation
Christopher J. Athmer
Chapter 28. Regulatory aspects of implementing electrokinetic remediation
Randy A. Parker
9. Table of Contents
SECTION IX: FIELD APPLICATIONS AND PERFORMANCE ASSESSMENT
Chapter 29. Field Applications of Electrokinetic Remediation of Soils Contaminated with Heavy
Metals
Anshy Oonnittan, Mika Sillanpaa, Claudio Cameselle, Krishna R. Reddy
Chapter 30. Field Studies: Organics-Contaminated Soil Remediation with Lasagna Technology
Christopher J. Athmer, Sa V. Ho
Chapter 31. Coupled electrokinetic-PRB for remediation of metals in groundwater
Ha Ik Chung, MyungHo Lee
Chapter 32. Field Studies on Sediment Remediation
J. Kenneth Wittle, Sibel Pamukcu, Dave Bowman, Lawrence M. Zanko, Falk Doering
Chapter 33. Experiences with Field Applications of Electrokinetic Remediation
Reinout Lageman, Wiebe Pool
10. Table of Contents
SECTION IX: FIELD APPLICATIONS AND PERFORMANCE ASSESSMENT
Chapter 29. Field Applications of Electrokinetic Remediation of Soils Contaminated with Heavy
Metals
Anshy Oonnittan, Mika Sillanpaa, Claudio Cameselle, Krishna R. Reddy
Chapter 30. Field Studies: Organics-Contaminated Soil Remediation with Lasagna Technology
Christopher J. Athmer, Sa V. Ho
Chapter 31. Coupled electrokinetic-PRB for remediation of metals in groundwater
Ha Ik Chung, MyungHo Lee
Chapter 32. Field Studies on Sediment Remediation
J. Kenneth Wittle, Sibel Pamukcu, Dave Bowman, Lawrence M. Zanko, Falk Doering
Chapter 33. Experiences with Field Applications of Electrokinetic Remediation
Reinout Lageman, Wiebe Pool