Invisible But Not Invincible Enemy - Hazardous Polluting Materials

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The CO2 and NO2 absorb infrared and cause global warming and hydroxyl radicals (OH) are very significant 'troposphere sink' for NO2 and SO2 gases.
The NO+NO2 are produced by aircraft and automobile emissions, biomass burning and lightening.
Both the CO with NO2 were noted to cause global warming denying any impact of NO2 on CO.
However both the gases don't have any direct impact on the climate but seem to control the major green house gases.
The OH is a chemical scavenger for the atmosphere.
Both the NOx and SOx with OH and H2O vapors form acid that damage the living beings.
There have been various additives, which effectively control the SOx by oxidizing the SO2 to SO3 forming stable metallic sulphate.
However the additives regenerate the H2X reduction but this method is very tedious and sophisticated in execution that requires a longer regeneration time.
Reportedly an oxidation of the SO2 to SO3 with both the cerium (Ce) and vanadium (V) metals was noted to increase the weight and confirmed the adsorption.
The CO2 adsorption using transient kinetic technique has noted a surface oxygen complex formation with different stabilizers.
This review is on the gas metal linkages with the vacant forces of the adsorbents responsible for adsorption.
In the year 1960s and early 70s, the control of NO emission by Cu based catalyst as CO+NO reaction was reported where an important issue concerning an oxidation state of the catalytically active surfaces were found.
For example the Cu/O2 system that changes to a gas phase and 'the steady state reaction kinetics' has been referred irrespective to the state of metals with variety of reaction mechanism.
As the X, X+, X2+ (X=metal atom) sites are all uncurbed in catalytic adsorption process with specific reaction for adsorption.
For a long, the IR spectra have been used as a best tool for detection of the metal gas interaction and a single crystal data under ultra vacuum condition provided basic information about an oxidation state.
The studies like Alumina as moderator for Cu as catalyst at NTP have been inferred by an in situ X-ray adsorption near edge structure (XANES) with first oxidation state of Cu as rate limiting step is indicated by Fernandez Garcia et al.
The electrochemical promotion by Na of CO+NO reaction over a Cu film catalyst supported on Na B" alumina, a solid electrolyte was carried out.
A brief literature review indicated that gas metal interaction has been a foundation for gas adsorption.
But in our technique metallic salts were used for gas adsorption, also the zeolites a porous material has been tremendously used for gas adsorption and separation as well.
As they have open crystal structure containing porous of molecular dimension due to shared oxygen atom of SiO4 and Al2O3 including the clinoptilolite (cp) which contain Na+, K+, Ca+ and Mg2+ channels and the device is tedious.
The surface site of coordinetively unsaturated cation and anions were in practice to adsorb NO on MgO powder.
Theoretically the DFT (density fundamental theory) and vibration frequencies calculated by abinitio has been used along with Raman spectroscopy.
It involves a complicated theoretical simulation and technique of crystallography.
The CO has been controlled by the hydrogenation method Zn/cu III, ZnO in Cu/ZnO catalyst model at high pressure.
Although the technique is purely chemical in nature, involving a reaction.
For this both the X-ray photoelectron spectroscopy (XPS) and IR have been used as detectors and the copper is refereed to as formatted species synthesized from CO2 and H2O on clean Cu (III) surface with adsorption model.
Platinum group metal surfaces were used for oxidation of CO to convert into CO2 by chemisorbing oxygen, CO before actual oxidation step.
Langmuir Hinshelwood mechanism (LH) was applied under 'steady state condition' and the reaction rate was determined which found functional to the amount of oxygen.
Still it has been seen that the exponential relation was of complicated nature and may not be applicable under NTP.
An adsorption of the CO on metal particles with carbon nano tubes as fullerene tube has been found of some use for the CO control.
The Rh/Al2O3, Ru, Ir and Re metals were useful to develop the nano particles.
It needs a little bit higher temperature above > 500 kelvin and (1-10 mbar) pressure, this technique is not workable under ordinary conditions.
It is of academic and materialistic interest and may be useful for technological purpose.
The oxidation of the CO2 by OH radical is the penultimate step in the complicated oxidation mechanism of hydrocarbon as per Lambert Beer law, using the transmittance (T%) for solution.
But for solid materials it seems to be the function of type and state of bonding.
The T for metal and their complex is found to be different however there are not much changes in the frequencies.
Thus the covalent bonding of metals are changed to complex bonding due to the new bonds developed in complex formation.
There may be a possibility that the IR light may strike the metal so the ligand may oscillate and its frequencies might be added to the transmitted light.
There is another threat of hydrochlorofluorocarbons (HCFCs) and hydrofluorocabons (HFCs) compounds which rapidly react with hydroxyl (OH) radicals reducing their concentration.
It depletes the ozone and hence the OH in optimal concentration in environment is essential but the CO quickly consumes them reducing their level.
This results into a rational increase in an amount of the CO2, CH4, N2O and O3, which are responsible for global warming.
Thereby the CO indirectly influence the environment.
The incomplete combustion in automobile industries releases the CO affecting every day life deadly.
Apart from the sulfurdioxide, carbon monoxide, nitrogen oxides and nitrogen dioxide, the volcanic eruption also releases the SO2, Therefore their control is essential and hence the work is undertaken.
Highly eco-friendly devices like survismeter are required to put to practice to curtail the pollutants.
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