[noise]
Hello, good morning everybody [vocalized-noise]. So, welcome to this class where we are talking
about the Mineral Fertilizers and we were with urea. So, we are talking in the last class about
the how we use the different kinds of ah is activity for urea and we have reached here
where we have seen that ah the certain kind of resin which are also made of urea [vocalized-noise]. And, so, if urea if you have as a raw material
you can get the corresponding urea formaldehyde resin as well as urea formaldehyde with another
component the third component is the melamine and you get that resin and we have also ah
told you that how that reaction-wise how the formaldehyde molecules are important in coupling
this urea formaldehyde resin formation; that means, the polymerization [vocalized-noise]. So, there are large other number of users
also urea has. So, one such example is typically a different
one where we can use urea as a selective non catalytic reduction material. So, the process is known as SNCR selective
non-catalytic reduction process [vocalized-noise] or selective catalytic reaction. So, we should have something where we see
that urea can function or can trigger those catalytic reactions to reduce the NOx pollutants;
that means, NOx pollutants we all know that these are the different types of nitrogen
oxides because we know starting from your NO symbol, NO – the nitric oxide [vocalized-noise]
and where you have the nitrogen oxidation state is plus 2 because the when you have
a nitrogen oxidation state of plus 1 it is N 2 O the nitrous oxide. So, nitrous oxide nitric oxide to up to you
can reached up to N 2 O 5 where the nitrogen oxidation state is plus 5. So, these properties we know a well and we
studied a lot about their reactivity pattern. So, in this automobile exhaust which is basically
polluting our environment particularly the large cities and the towns and the metropolitans
are heavily polluted with these NOx pollution. So, NOx pollution is nothing, but depending
upon the magnitude of x and the number of nitrogen; that means, the corresponding oxidation
states of the nitrogen it is corresponding potential for oxidation reduction whatever
you think off is completely different. So, when you have the oxygen you get that;
that means, that those NOx can be used as the typical oxidizing agents [vocalized-noise]. So, if you have some very cheaply available
and suitable reduction agent or reducing agent such as urea what happens? So, if you collect those exhaust gases because
the initial trial, the laboratory trial or some ah bigger scale trial for this reaction
we see that whatever amount of this NOx were present from the corresponding exhaust gases;
that means, the combustion of diesel, the dual fuel or the natural gas engines because
nowadays we know that we are running large number of auto rickshaws and all others by
LPGs or CNGs [vocalized-noise]. So, the natural gas burning process where
you have the corresponding hydrocarbons and we [vocalized-noise] have some the nitrogen
also because it is burning in presence of the air air as cynical amount of nitrogen. So, during that burning process also [vocalized-noise]
we produce the NOx. So, this NOx can now be used for the reduction
reaction with the urea. So, it can either be a catalytic process;
that means, in presence of some catalyst or it can be simple selective catalytic reduction
and non catalytic reduction also. So, we take the example of simple NO the nitric
oxide where x is equal to 1 [vocalized-noise]. So, the nitric oxide where the nitrogen oxidation
state is plus 2 react with urea which is CH NH 2 double ah NH 2 whole 2 CO with presence
of oxygen. So, the burning process what is taking place
in presence of O 2 giving you such a simple things; that means, it is producing nitrogen,
it is producing water and it is producing carbon dioxide. So, is a very interesting one that we are
destroying the NOx which has a severe polluting effect in the environment to convert that
NO 2 di-nitrogen molecule which is already a constituent in our air in our atmosphere
[vocalized-noise]. So, urea can that way is a very useful material
for tracking a tray tracking the corresponding polluting effect of NO or NOx. So, what ah the companies are trying to make
that they are trying to make something where you can have the corresponding ah chamber
where you can have a 32 to 35 percent solution of urea and through that urea solution if
we allow to pass this particular automobile exhaust gas which is known as the diesel exhaust
solution. You see the name basically the companies have
already arrived into the market they are producing that particular solution, they are simply
selling the urea solution. But, they are marked as the corresponding
diesel exhaust solution because it can trap the NOx from the diesel exhaust and it can
destroy those NOx [noise]. So, if the reaction is only water based nothing
is required because urea has a certain amount of solubility in water; so, injecting a water
based urea solution into the exhaust system or you can pass the exhaust gasses through
the urea solution it is again the same thing what you are trying to [vocalized-noise] get. So, when you get this we [vocalized-noise]
we can basically destroy the NOx from there. So, the thing is that what ammonia is produced
during hydrolysis we have seen last time that we can talk in terms of the corresponding
urea’s activity that urea’s is there in the soil material also. So, ureas which is available. So, that urea’s is responsible for the hydrolysis
of urea producing simply the material were from we got urea; that means, the carbon dioxide
and ammonia. So, ammonia which is being produced from the
hydrolysis of the urea can react with NOx how this reaction is going on whether it is
a reaction of urea only with [vocalized-noise] NO or ammonia with NO and is converted to
N 2 and H 2. So, this reaction is only that NH 3 which
is coming out through the hydrolysis of urea. So, we must have certain condition that in
C 2 we should be able to hydrolyze urea [vocalized-noise] to ammonia and that ammonia is basically reacting
with your NO or NOx producing N 2 and H 2 and at the same time during the production
of your ammonia carbon dioxide is getting liberated. So, within the catalytic converter everything
is happening. So, this particular one is the urea based
catalytic converter which can destroy the NOx molecules [vocalized-noise]. Now, we moves to [vocalized-noise] the metal
ion based fertilizers; that means, the potassium containing fertilizer. So, we have seen nitrogen we have seen phosphorus
and now we will see the metal ion containing fertilizer. So, phosphorus is basically a micronutrient
for the plant life it is available where is you get it. So, the availability is always very much important
otherwise you cannot start off, you cannot think of an industrial thing. So, if you last looking for the production
of potassium based fertilizer you must have a good source or cheaply available potassium
sources over there. So, we must know where from we cheaply get
the potassium like that of your sodium [vocalized-noise]. So, we can have numerous deposits like your
sodium chloride. So, sodium chloride we have seen that from
the sodium chloride stock; that means, the brine water or the sodium chloride deposit
the rock salt deposits we get sodium ah for its isolation and the isolation of sodium
as the different compounds [vocalized-noise]. So, this rock salt, the halite we call it
[vocalized-noise] is the rock salt is also once again another source very good source
of potassium because it also gives certain amount of potassium chloride from it because
potassium chloride is there within the rock salt [vocalized-noise]. Then only the silver ah potassium chloride
which is sylvine. So, sylvine is another ore type of material
or a deposit [vocalized-noise] natural deposit where from you get potassium chloride [vocalized-noise]. So, these are from sodium chloride certain
amount of potassium chloride and the potassium chloride itself in sylvine we can think of
certain thing where you can have also the magnesium and depending upon your percentage
availability and how quickly you can get that thing your magnesium bearing another production
chloride salt which is nothing, but a double salt type of thing of magnesium chloride and
potassium chloride which is potassium magnesium chloride [vocalized-noise] which is carnallite. So, carnallite is KMgCl 3 [vocalized-noise]. So, in some amount of is the typically a double
salt formula 1 is to 1 double [vocalized-noise] salt formula, but interestingly when it crystallizes
out it has a definite composition otherwise you cannot go for its crystallization. So, the challenge is that how you get the
typical ore source the mineral source the powder form and how you ultimately crystallize
it [vocalized-noise] because during crystallizes and you are also improving the quality of
the material, the purity of the material [vocalized-noise]. So, with hexahydrate form the carnallite is
crystallizing in it is pure form and when the composition of that carnallite is 1 is
to 1 potassium chloride magnesium chloride you must be sure that we have that particular
composition and it is separating as a pure salt [vocalized-noise]. So, this industrial processes based on this
type of salts is largely looking on the typical crystallization process or the fractional
crystallization process [vocalized-noise]. We can also have instead of magnesium chloride
we can have magnesium sulfate also what we known as [vocalized-noise] magsulf [vocalized-noise]. So, magnesium sulfate can also be useful and
now potassium magnesium chloride sulfate again you have [vocalized-noise] a formula of one
is to one of KCl and Mg [vocalized-noise] s SO 4 [vocalized-noise], but four of these
double salts are entangled or [vocalized-noise] having a network with eleven water molecules
which are known as water of crystallization in kainite [vocalized-noise]. So, these are the typical sources little bit
we should know and we should know about the sources where from we get because some countries
are very rich in these materials and some are not [vocalized-noise]. So, looking at from the industrial point of
view where you can start this industrial process of making potassium compound or making the
potassium based fertilizers we should always look at the corresponding availability or
the cheap availability of that particular material in pure form [vocalized-noise]. So, what we get is that when you make the
fertilizer we just simply put potassium chloride. So, the salt like your sodium chloride [vocalized-noise]
is the simplest possible salt once we just simply [vocalized-noise] give the input within
the fertilizer whether you have a nitrogen based fertilizer or a potassium based fertilizer,
but we put potassium chloride [vocalized-noise] and the remaining being [vocalized-noise]
potassium sulfate because you can have a corresponding check in the solubility. So, you have a basically a potassium chloride
and potassium sulfate [vocalized-noise] double salt into 9 is to certain percentage not even
9 is to 1 [vocalized-noise]. Then, you can have the potassium magnesium
sulfate ah the last one the kainite type of thing and the potassium nitrate is also added
[noise]. So, when we have these things and how we separate
out potassium chloride only because our basic intention is to produce quickly the potassium
chloride like your crystallization of sodium chloride [vocalized-noise]. So, the first step from a mixture of other
material; that means can the separation technique so, is the dissolution process where you can
see that the differences in solubility of the various salts even if you think of that
you have potassium chloride and you have sodium chloride [vocalized-noise] these two have
different solubility [vocalized-noise]. So, we must have a very good idea about the
solubility of the corresponding salts when we talk in terms of [vocalized-noise] your
dissolution process as well as separation by crystallization [vocalized-noise]. So, the various constituents what you have
of the raw salt in water and exploited to attain a high percentage because if you can
go for [vocalized-noise] dissolution and crystallization dissolution and crystallizes; that means,
fractional crystallization you can increase the corresponding concentration of say potassium
chloride at this point [vocalized-noise]. Then, we can go for the flotation where you
can have the different grain size different particle size depending upon the availability
of the coarsely inter grown minerals [vocalized-noise]. During crystallization as well as when the
mineral is forming on the earth crust basically the size of those particles are different. So, we can have a different ah separation
technique through protation [vocalized-noise]. Then, we have the electrostatic fractionation
[vocalized-noise]. Tribo-electrical charging [vocalized-noise]
which is some kind of charging and the charging is different for the different salt species;
if you have potassium chloride, if you have a sodium chloride, you have potassium nitrate
or potassium sulfate [vocalized-noise] the tie tribo-electrical charging the tribo-electrical
charging basically can give you difference in the charge and the corresponding relative
humidity of the air is required for a multi stage separation technique based on the corresponding
electrical field applied [vocalized-noise]. So, electrical charge separation which can
be achieved on the conveyor belt when the material is transported from one side to the
other and that particular electrostatic fractionation is always very important so that we just take
the help of electrostatics. So, electrostatic will help depending upon
the different charges, what the particles are accumulated, we can go for a very useful
separation which is a basically a physical separation [vocalized-noise]. Then, lastly we can go for a gravitational
separation because depending upon your particle size, depending upon your density of the particles,
density of the source; that means, the density of the particles for the corresponding [vocalized-noise]
minerals or the ores because depending upon it is different types; that means, whether
you have a pure potassium chloride sample or it is mixed with magnesium chloride or
it is mixed with magnesium sulfate, you can have the differently dense material in your
hand [vocalized-noise]. So, we go for salt solutions containing ferrosilicon
sub as the gravitational liquid. So, one particular gravitational liquid because
dense liquid you should use and particularly that dense liquid can separate the heavier
particles will settle down and the lighter particles will float like that of our separation
based on water or any other solvent. How we make now potassium sulfate if we are
able to make potassium chloride nicely in an industrial scale to a huge amount [vocalized-noise]. So, the reaction the typical reaction text
book reactions are very simple that if you have huge amount of potassium chloride you
try to react with sulfuric acid already we know that this mineral sulfuric acid we have
already we know how we prepare it. So, the industrial supply of that mineral
is very much in hand. So, you directly react with sulfuric acid
giving you potassium sulphate. But, sometime the whole potassium chloride
can be reacted in C 2 with sulphur dioxide also when [vocalized-noise] we do not want
to use sulfuric acid because the sulphuric acid is a costly material. So, if we want to go down its corresponding
price for the process we can use directly the sulphur dioxide which is the raw material
for sulfuric acid production and the equivalent amount of oxygen from the air or some other
sources and water which is ultimately giving you during this reaction process the sulfate
formation [vocalized-noise]. So, in presence of KCl what you can think
of this particular second reaction you look at that particular second reaction, you try
to write it that reaction and what you can think of that in presence of KCl what we are
doing we are also forming sulfate anions from sulphur dioxide which is not so easy all the
time; [vocalized-noise] that if you have sulfur dioxide it will not very much react with what
are as well as O 2 to give you sulfate very quickly. But, potassium chloride now can have some
catalytic effect for that particular conversion because the form material what is being separated
from the medium is your K 2 SO 4. So, this particular process or the procedure
is known as Hargreaves process. So, Hargreaves process is that particular
process either you use sulfuric acid or sulfur dioxide for the production of K 2 SO 4 [vocalized-noise]. Then, a particular technique all the time
we should follow this particular one and we should be you should be asked also when during
your exam time [vocalized-noise] that a particular type of metathesis reaction you always keep
in your mind that what is that particular metathesis reaction and how this metathesis
reaction can be useful to get some useful compounds. So, how metathetically the reaction is useful
[vocalized-noise] for the conversion of potassium chloride to potassium sulfate. Just now we show that one particular process
is useful in presence of sulphur dioxide [vocalized-noise], but if we are able to go for a corresponding
metathesis reaction and that metathesis reaction is nothing, but [vocalized-noise] the exchange
of the cation and the anion part [vocalized-noise]. So, what you should use whether you use? sodium sulfate, aluminum sulfate, iron sulfate
or that particular magnesium sulfate which can be available at a low cost or low price. So, if you have a very low price material
magnesium sulfate in your hand [vocalized-noise] you can try for that reaction in presence
of water and that reaction will give you a double salt of magnesium sulfate because magnesium
sulfate what is being used [vocalized-noise] is directly giving you the corresponding double
salt when you produce also the potassium sulfate which is also known as the Epsom salt. So, that type of all sorts of double salts
there are available. So, your starting component; that means, whatever
magnesium sulfate is we are using, [vocalized-noise] your basic intention or basic idea is very
simple that you are not only producing potassium sulfate because our idea is not you produced
potassium sulfate because the price of potassium sulfate would be less compared to your this
particular complex double salt. The way we know also that when we make the
more salt which is ferrous ammonium sulfate [vocalized-noise]. So, it is basically a stable one and which
is not easily oxidized in air to ferric sulfate [vocalized-noise]. So, definitely the usefulness of that material
is higher compared to your starting ferrous sulfate [vocalized-noise]. So, your cost will be more, the market demand
is high. So, industry will try to produce that double
salt fast. [vocalized-noise] Similarly, this particular
double salt the Epsom salt so, is very useful and is costlier compared to your both potassium
chloride and magnesium sulfate. So, it is the typical crystallization process
or double salt formation which is [vocalized-noise] we can consider as a value added process and
that value added process directly give you a good quality a very pure quality of the
corresponding salt which can be marketed directly from there [vocalized-noise]. So, this double sulfate what is formed in
the medium what is formed in a saturated solution [vocalized-noise] can be separated and can
further be reacted with additional potassium chloride [vocalized-noise] because whatever
part one part is going as the magnesium chloride, so, this double salt can be separated and
reacted [vocalized-noise] during the reaction with the addition and potassium chloride you
can get that again you have the magnesium source again you have the potassium chloride
salt. So, only thing that if you think of now for
the next step you can think of that you can have certain amount of sulfate salts [vocalized-noise]. So, this particular one so, in between that
as intermediate you have this double salt [vocalized-noise] and that double salt is
further reacted with the starting potassium chloride [vocalized-noise]. So, the starting potassium chloride is reacting
and when you think that the entire amount of sulfate anion what was available from your
magnesium salt is converted to your potassium salt and always remember that the solubility
of potassium sulfate is more. But, due to this typical mass action reaction
[vocalized-noise] more and more amount of potassium sulfate will be forming [vocalized-noise]
and less amount of magnesium chloride it may remain in solution in a supersaturated form,
but it will not [vocalized-noise] crystallize out with that of your potassium sulfate [vocalized-noise]. So, this crystallization technique are all
the time very useful and it can apply for also your formation of potassium nitrate because
the [vocalized-noise] nitrate salts are much more soluble than your corresponding sulfate
salts [vocalized-noise]. And, now directly we can use this particular
one and you can remember where we can have the corresponding chlor-alkali process that
where we see have seen [vocalized-noise] that electrolysis of sodium chloride can produce
you give you the sodium hydroxide can give you the chlorine can give you the hydrogen
also. Similarly, during the production of potassium
nitrate which can be industrially very beneficial also and you can use the mineral acid nitric
acid; not any other nitrate salt by metathesis or double metathesis type of thing [vocalized-noise],
but directly the acid is used for it is corresponding anion supply in presence of oxygen because
oxygen is utilized for your oxidation. So, [vocalized-noise] as we all know, that
both nitric acid and oxygen both of them are oxidizing agent [vocalized-noise]. So, you can have this particular effect, but
the consumption of nitric acid as the oxidizing agent is not taking place here because we
want to have the intact nitrate as the anion from nitric acid to be converted to be taken
away by potassium ions to form potassium nitrate [vocalized-noise]. Only the oxygen what is used for it is reaction
that oxygen is utilized for your oxidation of chloride ion to produce chlorine [vocalized-noise]. So, not only you are making potassium nitrate
in this particular reaction, but also you are producing chlorine. So, you have to separate that is a gas which
is coming out from the reaction medium, from the top you can collect it and that particular
collection we can store it and we can [vocalized-noise] in you can put everything in the cylinder
for storing chlorine also [vocalized-noise]. And, the process is in fact, much more complex
than the equations shown because this rate equation. So, everywhere as I told repeatedly every
time I mention [vocalized-noise] that whenever a particular reaction is shown because we
are talking in terms of the and then we are talking about the corresponding part where
you can have the corresponding complications [vocalized-noise]. So, whenever we write a particular type of
reaction, it is not very easy to do that particular thing in industrial scale. So, the reaction is much more complex because
you are using huge amount of the material and that material is not able to react directly
when you increase the bulk of the material say for this example of this KCl this KCl
here when this KCl is a reacting that KCl amount basically because you have a huge amount
of that [vocalized-noise] KCl [vocalized-noise] whether you take that as the granules whether
you take that as the powder or in some other form basically in solution also [vocalized-noise]. The contact with nitric acid as well as the
contact with another gas component which is your O 2 is not uniform not all the time very
easy to go for molecule by molecule or ion by ion reaction because everything what is
happening at the molecular level. So, molecular level reactions always we should
think in terms of [vocalized-noise] the reactions with one molecule to the other [vocalized-noise]
and when the reactions is in very dilute form. So, whenever we have some reaction in test
tube [vocalized-noise] in a very low concentration not even the molar concentration or the normal
concentration less then [vocalized-noise] deci normal it can be centi normal or it can
be mill normal or milliliter scale. So, we should always think of the reaction
is very simple and reaction is very straight cut, but when you use some kg scale only;
sometimes some kg scale gives us all the difficulties that is why the industrial process engineering
is there because the processes would be different, the reaction chambers should be different,
the reactor should be different otherwise you cannot achieve that particular reaction
by looking at only the feasibility of that particular reaction. So, reaction can be pretty complex [vocalized-noise]. So, when we go for manufacturing these with
metathesis with other nitrates like sodium, calcium and ammonium nitrate it is also possible
instead of using nitric acid. So, [vocalized-noise] you now know that, what
are the different things you can use to convert your potassium chloride to potassium nitrate. It is the choice which will be in your hand
[vocalized-noise] whether you go for the reaction what is given in the equation; that means,
the direct reaction of the material with nitric acid in presence of O 2 or you can use some
other nitrates which can be even costlier [vocalized-noise] than the product which you
are looking for like your potassium nitrate [vocalized-noise]. So, use of sodium nitrate, use of calcium
nitrate or use of ammonium nitrate whether they are giving you any kind of benefit with
regard to the cost we should always be very much careful for that otherwise we can go
for some traditional processes because to make this salt we always look at the very
cheaply available nitrate source if your nitric acid is cheaper than sodium nitrate which
we should go for this particular reaction [vocalized-noise]. So, the metathesis reaction is very simple
and is a very direct one. So, you have KCl reacting with sodium nitrate
you have the corresponding one; that means, you can get it for your simple thing; that
means, the sulfate salt also. Why you are taking the second equation is
that [vocalized-noise] if your potassium chloride is costlier than potassium sulfate, so, we
directly take potassium sulfate because we are using some [vocalized-noise] nitrate which
is your calcium nitrate and as you all know calcium sulfate has a component of the gypsum
material is readily available and also it is solubility is less as is monohydrate and
dihydrate is the calcium sulfate what is available [vocalized-noise]. So, gypsum what we use as the calcium disulfides
and the plaster of Paris; plaster of Paris is the monohydrate one while one of the water
of hydration we take out and that can readily take back that particular material and give
you the corresponding plaster of Paris for very many purposes like your simple coating
of the ah [vocalized-noise] our walls into a interior walls of the building [vocalized-noise]. So, POP vocalized-noise] coating we call this
a POP plaster of Paris coating which is we can get it from your calcium sulfate dehydrate. So, along with your potassium nitrate what
we are making here is that we are getting some amount of gypsum type of material in
our hand [vocalized-noise]. So, we are finishing here the mineral fertilizer
part. So, we will be coming here next like in our
next class that the other area where we can talk about the metals as well as they are
compounds [vocalized-noise]. So, so far whatever we have talked about particularly
this ah mineral fertilizers we have also talked about the potassium as your potassium sulfate,
potassium nitrate and potassium chloride preparation. So, if you consider that can also be a corresponding
metal as well as the metal compounds that will see our in our next class, ok. Thank you very much [vocalized-noise].