 Hello guys. Good evening. Can you hear me? Okay. We'll wait a few minutes for others to join and then we'll start. Okay. So guys Yeah Today, we are going to start a new chapter metallurgy. Okay, so Like we'll finish this chapter today itself. Okay. We don't have much to study one class four hours is enough You know for this topic If you look at the importance, I did not Check I did tell see, okay Yeah, I did tell us drop me a high. Okay, I did a C. Yes, sir. Yeah Okay, so like if you see this particular chapter, I think from the board sleepers also, they have to move for this year, right and As far as competitive exam is concerned this chapter is not that important especially for Jay Okay, for other exams like bit set CT. They ask you, you know Theoretical questions on this. They're not any numericals. You're going to get in this particular chapter. So it's basically Theory you have methods, you know process by which we can extract metal from its ore. Correct So metallurgy is all about extraction extraction of metals like copper zinc iron Aluminium right, how do we extract metals from its or? you know What is the property of the ore of the given metal and based on the property we choose various processes Okay, so what are those process? Right based on property. How do we choose the processes for the extraction of a particular metal? That is what we are going to see Okay, so basically if you look at this all this stuff, you need to know the properties based on the properties will have the purification of metals so if you look at These elements or matters that we have in earth cursed They're available in combined state Right, if you look at elements elements in earth cursed they occurs in or exist in Combined state correct element occurs or exist in in combined state So basically, you know all these elements metals, whatever you say, okay They reacts easily with oxygen. For example, you say that they can react with moisture They can react with other chemical elements also and exist in the form of in the form of what in the form of compounds We haven't no DNF block. We don't know what is the last portion we have done Dnf block So we were just doing zinc sulfate All right, so it's done I think few compounds are there just one or two three compounds are there if you look at the you know chapter There's so many compounds given okay, so most important one we have done I said last class that other compounds you can go through on your own. There's nothing Okay, so yes, that was my understanding Hence, I'm starting this particular chapter. If you want you have any doubt we can do that later on. Let's continue with this Yes, yes, yes, and these NCRT is more than that you can go through. So I think we are done with DNF block. There's so many compounds if you look at the books, right? But all those compounds are not important important one we have discussed you need to focus on NCRT for these chapters Okay, not more than that Yeah, yeah Okay, yeah, so that is what I was talking about elements So in this chapter again, I'm repeating in this chapter. We are going to study about the extraction process Of metals correct. That's the basic thing we have only one particular You know thing is important for J point of view. That is elingum diagram Okay, elingum diagram is important for board also But since this year you don't have this chapter in board slavers. So that is also gone, right But for J point of view elingum diagram Properties what all information we can extract from elingum diagram that you need to focus on Okay, all other things are not that important for J Okay, so yes, so element occurs Or exist in combined state All these elements like under different different conditions They may combine with oxygen moisture or other chemical reagents and occurs in combined state Right, for example, you see non metals mostly exist in the reduced form. Okay, so I'll write down here Nonmetal for example, you see non metals exist in Exist in reduced form Okay reduced form means what for example if I take the example of halogens They exist in the form of x minus cl minus br minus i minus etc Reduced form they exist in the form of halides. Okay Metals which we are going to focus on in this chapter metals are No, they're they are reactive towards oxygen. So they generally exist in the form of oxides. Okay, so metals metals exist in the form of oxides For example, you see we have Al2O3 Aluminium oxide alumina we call it as iron oxide is Fe2O3 etc So our job is to extract These metals like aluminium from its oxide iron from its oxide It's not necessary that will always extract metals from its oxides only Which compound we are going to choose For the extraction of metals that depends upon several You know several conditions we have for that Like suppose you need to extract aluminium. Correct So we have aluminium cut different different compounds. Correct. So if you take one particular compound Yes, right angle, right if you take one particular compound You need to think of the convenience of the process that we are going to use to extract the metal. So The process must be convenient and economical For the extraction of metal There's no any point of extracting our metal and you are putting so much of money behind it Right, because eventually you have to make profit out of it. Correct So we we choose those compounds only From which we can extract metal conveniently and economically Right so among all those compounds of one particular metal Those compounds that we choose for the extraction of metals we call it as ores Right and all these compounds like I have written over here the Elements which occurs in combined listed. So the compound that we have those compounds we call it as Minerals. Okay. So whatever the compounds we have for any given metal All those compounds belongs to the category of mineral Among those compounds one particular compound that we use for the extraction of metal We call it as ores Correct. So all ores are minerals, but all minerals are not Ores, okay. I hope you understand it the two points we have over here We first of all you write down the definition of minerals minerals Write down compounds of metals which are compounds of metals which are naturally available naturally available naturally available in earth's crust in earth's crust and can be obtained by mining can be obtained by by mining called Minerals Right Next definition we have that is ore definition write down These are the minerals from which These are the minerals from which from which a metal can be a metal can be extracted extracted economically extracted economically and conveniently Conveniently are called ores So basically minimum input maximum output Okay, in the most Excuse me economical way. Correct. One last point after this you add all Minerals are ores But all ores are not minerals vice versa is not true Okay, example you see Yeah Example is suppose FES2 It is a compound of iron We call it as iron pyrite Like this you will get many compounds over here in this chapter for which you need to memorize the formula plus name Okay, because not in j e sometimes in need and sometimes in other You know, a reasonable exams like bitsat and others they ask, you know questions on this just a second Yeah FES2 we have iron pyrite is a mineral, okay We don't use iron pyrite for the extraction of iron right is a mineral Not an ore Why because FES2 the extraction of Iron it requires high cost of production. Okay, so it is an ore. It is not a mineral Okay, we have one more term over here, which we call it as gang Gang or what gang are basically the impurities Okay, these are the impurities present in the ore Present in the we call it as gang So these are some basic definitions we have that you Need to memorize not much important by the way just you need to know that what is mineral? What is what is the difference? Okay, so what we are going to do here Our next, you know, we are going to understand the various processes That we use for the extraction of any metal in general we discuss It's not like we are going to do one specific metal. Okay, that that is what we are going to do We'll do in the last one or two metals will do but the process that we are going to use whatever metal we have More or less we are going to have all those Processes only that we are going to see next. Correct. So we'll discuss The process first. What is the overall process we have and how do we extract in given steps? What are different different methods we take for the separation of metals from impurities? Okay, based on the properties of the metal and impurities We use one particular methods for the separation of What we say metal, correct? So we'll discuss some general methods In different different steps and those methods only We we were, you know, we will be using for the extraction of a given particular metal One or two steps may be different here and there but more or less the concept will be that only but before going into The no the methods or the process we have for extraction of any metal We will discuss we'll see some compounds and its molecular formula Like I said, you need to know some compounds and their molecular formula I'll write down few compounds here. You also copy it down And you have to memorize it. Okay, it is important Like I said, not for Je but other examples. They ask these questions directly Okay, some examples of no Compounds you write down here Like the first one we have Heading you right on chemical formula Chemical form these data I have taken from, you know, different different books and CRT also I have you know referred for this So all those examples which are given in NCRT that is also important here. So the first one is you see The first one is gencite Gencite you should know the molecular formula. Its molecular formula is ZnO Correct. The second one Is Fe2O3 Fe2O3 the name is I'll write down the name first way it is hematite It is hematite Fe2O3 Okay, magnetite magnetite is Fe3O4 Okay, next is pyrolocyte Pyrolocyte mineral you must be, you know, remembering this we use this for the preparation of KMNO4 Right, MNO2 Next is Cassiterite C A double S E T E R I T E cassiterite it is SnO2 We also call it as tin stone Tin stone Copy this down. I'll go to the next page Let me know once you're done When oxides of uranium That is uh, we call it as pitch blend Formula is U3O8 Boxite Boxite is Al2O3 Dot 3 H2O Okay, galena. They've asked many times this galena Galena is lead sulphide PBS Cinnabar also they have asked in the exam Cinnabar is sulphide of mercury HGS One second Siddharth you can copy this done. I'll go back again. Okay Numbering here and there will not affect much. Okay, just to copy this on I'll go back up to this. Okay Okay, Cinnabar is HGS Fools gold This also they have asked in the exam Fools gold generally this kind of question that is E T mid-sat and off Fools gold is iron pyrite Fe S2 urgentite Is ag2s like all these are sulphides basically Okay ZNS also they have asked many times zinc blend we call it as Zink blend is ZNS. Okay copper pyrite is Cu Fe S2 copper pyrite Chalco pyrite also we call it as copy this down Chalco pyrite Okay, Siddharth copy this down done Siddharth Okay, finished all of you done Okay, few more compounds. We have here the next one is Indian salt pitter is KNO3 Chili salt pitter is Na NO3 AgCl like I'll write down the name first Horned silver Many times they have asked this question horned silver Horned silver is AgCl Okay, cryolite Cryolite is Na3 ALF6 cryolite. Okay Floors part That is Ca F2 Silvine silvine also they have asked in the exam Silvine is CaCl Okay, Magnesite not much important this one But this is a known compound to you. It is MGCO3 Magnesite Okay dolomite important this one dolomite Dolomite is CaCO3 It is an addition compound of calcium and magnesium carbonate Ciderite Ciderite is FeCO3 And the last one we have is Calamine Calamine also they have asked in the exam Calamine is ZNCO3 Zinc carbonate So I have written so many in all these compounds you see this is important This is important like the one which they have asked many times. Okay cryolite also they have asked Horned silver also they have asked Okay, these two also they have asked here This last slide is the most important one These are the few things that you need to memorize Next is The one that is no for this chapter we have Is to understand the process of extraction Okay to understand the process of extraction This is what the entire chapter is all about Okay So like I said, we will first discuss the general process of extraction. What are the methods we have in this? involved in this and based on the property of The impurities and And metals we use one of those methods for the extraction process So overall the the you know the map of extraction is what you see we have An ore first Right, so we have first of all we'll choose the ore From this ore We'll do the concentration of ore and this concentration term has nothing to do with the concentration morality morality Concentration of ore means we also call it as ore dressing. Okay. So basically we prepare ore for the further processes of extraction Okay, that we call it as concentration of ore So next step is the concentration of ore concentration of ore We also call this partly Concentrated or because obviously in one step you cannot remove the entire impurities Correct. So step by step we'll do right. We use different different reaction. We mix different different compounds So that we can remove the impurities from that. Okay. The same process here I'll just change the color and light down here the same process. We also call it as ore dressing ore dressing once you are done with it You will get what you will get Concentrated ore right from this step second step Next you will get the concentrated ore So this is the Concentrated ore we have you'll get the concentrated ore With this concentrated ore, I'll write on steps also involved over here We further get impure metal impure metal Okay, and then we'll apply some methods into this then we'll get the pure metal in the last which is our objective here Right. So after this we'll get the pure metal So basically the method that we use here. We use different different methods in the first step Okay I cannot write down the entire process over here But overall the thing is this only we can use here in this step after taking ore. We can use floatation We can use floatation method where we use the you know The grinded ore will put into the solution and we'll mix it properly so that the froth forms Right, which we can take it out Like it it is you know, we use this method when we have the difference in density Between the impurities and the ore don't write it on this listen to me because one by one we'll discuss all these steps Okay, where I'll write down I'll tell you that what is the condition we have to use this particular methods Okay, so floatation is one of the method another method is hand picking Suppose you have this sample, right? Let me just write it down Where we have, you know, suppose this is the actual metal particles we have present here Which obviously makes it's not like it is separated in this also we have mixing of metals, right? So this is the ore particles mixes with some impurities and apart from this there are others, you know Impurities also present like this suppose which you can easily identify with the naked eye Right like this suppose unwanted or impurities are present over here unwanted particles or impurities are present Which you can easily hand pick, right? We can look at it and you can remove it to handle right manually you can do this Right by physical methods. So hand picking is also one of the process in the concentration of ore, right? All those impurities which you can see observe, right? You can hand pick those particles that is one part of concentration Okay, so hand picking is one of the method we have hydraulic was also gravity separation method we have over here Right, we have froth flotation also we have over here, right? We have electromagnetic separation when the metals are impure are you know present over there Which contains magnetic properties and impurities does not show any magnetic properties So in that case, we can use magnetic separation, which we also call it as electromagnetic separation Right all these processes we can use Once the concentrated ore you get okay after concentration is done Concentrated ore you get then we use to you know reduce because usually we get near oxides of metals Which we can reduce and we can remove oxygen and we get impure metals over here Which we can do for purification So what are the different steps we have that we are going to Discuss now always keep that in mind Concentration of ore has nothing to do with the concentration term that we have done so far, right? It only and only means that we need to prepare ore for the further Processes right which we call it as concentrated ore correct so This is the entire the flow map of extraction processes Now we are going to discuss One by one. What are these steps? What are the processes involved in these steps and what is the property required property for metal and impure? Okay, so first step you write down the first step is Is grinding grinding and pulverizing grinding and pulverizing i'll tell you the No method what we have all these methods See what happens in this the ore that we get from earth crust generally these ores are present in the form of big lumps, okay because It is the you know it is present in the combined state No, so it is possible that the ores are present in a big lump size is big over there Okay, so what we do first of all we take all these you know ore particles the lumps that we have And we break down this into small pieces First of all right we break down this into small pieces Right and this we use in crushers or grinders. So this process we call it as grinding process understood to break down the Ores which is present as a big lump Into small pieces is grinding Which we usually done in crusher or grinders Okay, what is pulverizing pulverizing is even one step You know further you need to go not small pieces. You need to you know convert this into Powder form right fine powder form which we used to do in ball mill Okay, ball mill is the name of the Device or we can say the machine that we use for the process of pulverizing Okay, if you study mechanical or chemical engineering You'll be dealing with all these you know machines in the lab in your Injuring college right like I said ball mill you have you have you know crushers You have all these civil engineering also we have these kind of application So grinding right down in this quickly right Ores obtained from the earth crust I'll also write down once again from the earth crushed Is generally occur Is generally occur in the form of In the form of big lumps Next line grinding is the process grinding is the process We use to We use to Is the process we use to convert Or not convert convert you don't write we use to break down Break down the ores into Ores into small pieces Small pieces and for this what we use we use grinders. We use crushers The machine that we use here is grinders Grinders we can use we can use crushers for this process Okay grinders or crushers not important this you don't have to memorize Okay Next line write down in pulverizing write down next In In pulverizing the small pieces the small pieces Are reduced to reduced to fine powder Are reduced to fine powder with the help of Ball mill Ball mill like I said again a You know device we have the machine that we use for Reduce the size of the particles so first of all we took the we take the Ores the big lump then you We break this down into small pieces Or fine powder. This is what we have in grinding and pulverizing the first step is this See any process Venkat if you see any process that is required First of all small pieces A small size will have large surface area Right so we can have better interaction with other reagents Right if some reaction is to take place Or if you want to prepare a solution Right suppose flotation process you have right Where that that we use when we have difference in density between the metal and the impurities So what happens when you mix this powder into the solution right it forms froth we continuously mix this So it forms froth right so heavier density substance that settles down and lighter densities That that will be at the surface with the froth Which we can easily filter out Are you getting my point got it so if you don't don't break down into small pieces You won't be able to prepare the solution out of it. It won't mix properly Oh, okay, sir. Okay for better reaction Happening. Yes, better reaction. You can say or to prepare a solution for other processes for the steps. You need to No reduce the size of the old particles that you are getting Oh, okay, sir Correct. So this is the uh first step that is grinding and pulverizing One second Sasham granny Uh with the help of the It is the ball mill Ball mill is the machine that we use reduce the fine powder with the help of the ball mill ball mill is the machine Correct. Now, this is the first step which is done grinding and pulverizing. We are done with it Next step is the concentration of ore Concentration of ore which we also call it as ore Dressing So it's it's kind of will dress up ore for the further processes right Correct. So it's like, you know, uh In in this process what happens? all those impurities Which can which we can remove easily without any chemical reactions Like I took the example few minutes back of hand picking Those kind of process takes place into this Okay, or some physical, you know processes like we have hydraulic washing Okay, gravity, which is also known as gravity separation method. Okay, we use in this process So concentration of ore write down write down the metallic ores I'll also write down. Otherwise you'll get confused Copy this down the metallic ores Ores obtained from obtained from earth crust are often mixed with non-metallic non-metallic and rocky materials ROCKY And rocky materials Rocky materials such as such as we have sand clay, etc So we'll mix all this sand clay right limestone So metallic ores obtained from earth crust are often mixed with non-metallic and rocky materials that is sand clay limestone, etc Right correct We mix this and then we'll allow this mixture with ore and this The the non-metallic and rocky material that we add we allow this to pass through a You know gravity separation process. We have hydraulic You know Classifier there as machine. We call it a hydraulic classifier From which we allow this mixture to pass through and then we'll see what happens in this I'll show you the diagram also over here. But in this first two one two points again you write down here We know the impurities present in the metallic ores are called gang. We also call it as matrix Okay Gang or matrix are the same thing. Both are impurities. I'll just write down here Gang and matrix So both are impurities Gang or matrix both are impurities. Okay write down the concentrated ore the concentrated ore Which is also relatively purified The concentrated ore is called concentrate Okay, the concentrated ore is called concentrate Right this process concentration of ore this process. We also call it as benefaction process Just we have different different names purposes say B E N E F A C T I O N benefaction process Concentration of ore is called benefaction process Now what we do for the concentration of ore what we do for the benefaction of processes, correct? a benefaction process The first method like I said under this concentration, we can do hand picking Okay, I'm not dictating you anything into this. You already understood. What is the meaning of hand picking we have So we can do hand picking We can also do a hydraulic washing hydraulic washing Right, which is nothing but the gravity separation method gravity separation method Copy this down So hydraulic washing or gravity separation methods when we use what is the condition we have to use this method Okay, so we'll use this method when there is a difference in specific gravity Condition is what the condition is we have difference in difference in specific gravity between gang and ore We must have difference in specific gravity between the gang and ore if you have You know difference in these two things gang and ore Then we can use this method that is hydraulic washing or gravity separation method for the concentration of ore Okay, so based on the property we use this copy this down Now under this hydraulic washing or gravity separation. We also have different different methods again. Okay So under this you write down we have two processes two methods we have So first one you write down a That is will flay table method will flay table method Now I'll show you the diagram of it the picture how it we use this particular thing see this This is the will flay table Okay, so the powdered ore that you have concentrated ore. See you will understand the process easily here These are the plates you can say tray we have on which we'll put this powdered ore over here We have an inlet of water pipe which sprinkles over here on this tray And then it comes down on the disk table this table This is the vibrating table we have we have some arrangement so that we can shake or vibrate this table continuously It continuously keeps on vibrating. Okay So what happens the concentrated or the ore that we have since we have difference in Specific gravity all the concentrated or or they will you know shift towards the Right right of the table or our left towards this side and slowly it comes down from here To this side and it will accumulate somewhere over here And the gang or the impurities it will come along with the water and it falls down over here This is what the gang and the little slits we have slits we use to separate the you know the ore and the Impurities present into this metals and the impurities present into it. So whatever I know Uh Compounds elements in which there is a difference in gravity that will be separated by this method like okay, you understood So i'm not going to dictate you the theory in this. I hope you can understand with the figure how this process we use correct Just a second. I'm coming. I'll take some water one second Yeah, one second guys Yeah, so this is will play table method. We are doing this under Concentration of ore. Okay. Keep that in mind under concentration of ore. We have hydraulic washing Gravity separation method under which we are doing this will play table method We have second method in this Okay, both we can use When we have difference in specific gravity on this particular information they ask question in the exam sometimes Okay, so if there is difference in gravity of specific gravity of you know Of a gang and metal we have then what which method we'll use so name you just keep in mind another one is hydraulic Classifier method. Okay, the b is hydraulic classifier method. Okay hydraulic classifier method. Look at this, you know diagram hydraulic classifier is this Try to understand the working. That is it. You don't if you understand this Uh, obviously in board the chapter is not there Or j may and in other exam. They won't ask you to you know Write down the entire process how it happens. Okay, so these things are not important as far as as the exam is concerned Okay, so what we do here we have a hopper correct from which we We put the powdered ore into this entire system, correct and from the bottom we You know, there's an inlet of water here. You produce water from this high force of water will be there So here it'll get mixed suspension forms over here suspension of ore. Okay, and we keep on you know Blowing water into this right so slowly the metal particles Right the concentrated ore since it has higher density it will settle down slowly Comes back into this container and we collect it from this outlet The gang particles which are what lighter because we have difference in gravity Especially gravity. So it will be on the top mostly So some part of it will come out from this outlet, which is the gang particle. Okay, understood this So this is the conical reservoir fitted with a hopper Right, it is a hopper Conical reservoir is this fitted with a hopper We used to when if like, you know There's no point of discussing all this thing because you are not going to get this in the schooling But yes, the method is this only Understood So working you just keep in mind how it works if they frame some questions in the exam any exam comparative exam Then you can answer it properly. Okay condition is same difference in specific gravity will be there The lighter gang particles are carried away by the current of water and heavier old particles collect at the effects of the cone the term that we use okay effects of the cone The term that we use gang particles are lighter We'll collect it from the top from here Okay, one more thing based on the design of this vessel The classifier that you have it is in the conical shape here. You see it is a conical shape that you have Obviously the bottom is not circular but with this narrow part that we have here What it does actually it, you know, it reduces the velocity of water the water that you are You know pushing in the high current of water From the bottom. So because of this, you know, a narrow portion of the tube that we have the velocity of the water decreases And because of that the metal particle which is here, which is heavier, right? It does not carry away If the velocity is very high, it is possible that it will push the metal particles also in upward direction But two things because of this narrow part here over here the velocity of water decreases Right and the metal particles which is already heavier because of difference in specific gravity So this reduce in velocity of water plus the heavier metal particles both, you know You know both what we can say The metal particles that you have It slowly settles down and comes over here But this current is sufficient enough to blow this, you know The lighter gang particles that we have which first of all comes over here and we That is what the construction part that we have why we have this conical shape Because it reduces the current of water and helps settling down Helps in settling down a settlement of the metal particles over here in this tank But like this is the purpose we have over here. So this is the you know Two methods we have in hydraulic washing or gravity separation method All these things again. We are discussing under concentration of ore the next method we have In concentration of or the third method Third method is write down all of you the third method is electromagnetic separation Method electromagnetic separation method I'll first show you the diagram for this And then we'll see The important points in this will write it down Okay, electromagnetic separation with diagram itself. You understand that what kind of Properties required for this kind of processes. Okay, so electromagnetic separation. You see this Okay, so we have a roller over here and a hopper Right just above the roller. We have a hopper and this is the Belt we have this is a magnetic roller and we have a belt over here Correct the finely, you know powdered ore We put this into this hopper and this roller is continuously moving Like it is moving in this direction It is moving in this direction. So obviously the ore particles which comes over here It starts traveling like this and it goes till here the one which is you know, which is Which has the magnetic properties, right? It will be in touch with the roller for a longer period of time and it will fall somewhere here right all those, you know non-magnetic particles It will lose the contact somewhere over here because it is rolling like this Like it will lose the contact somewhere over here and since the particle has a tangential velocity over here So it will fall down somewhere here Means you will you'll get the two different, you know points where the Magnetic particles and non-magnetic particles will come and hence we can separate the two here Correct. So obviously this kind of separation method we use when there is difference in the magnetic property of the metal and the Impurities which is present Correct easier one. You can understand this here. There's a few points to write down here. This method is based on This method is based on this method is based on Magnetic and non-magnetic properties of ore magnetic and non-magnetic properties of ore and the gang respectively magnetic and non-magnetic property of ore and gang respectively So ore is magnetic over here. You see the magnetic particle is the ore. This is ore Wait This is ore and this one is gang So like this the gang and the ore particles are separated by electromagnetic separation method, okay For last point you write down here This method can be used to separate This method can be used to separate Chromite ore chromite ore is This Used to separate chromite ore that is Fe CrO2 Chromite ore from From silicon impurities like siliceous. We also call it as From siliceous impurities Okay So this is the third step we have Under third method. We have under Concentration of ore electromagnetic separation Okay, I have written it twice magnetic over here. It is electromagnetic separation method Okay, next method we have in this in concentration of ore the fourth one you write down The fourth one we have Is froth flotation method Froth flotation froth flotation write down in this first This method is used Or this method is based on Is based on on different wetting characteristics wetting characteristics wetting characteristics of ore of ore and gang by Oil and water Different wetting characteristics we have by oil and water write down ore is mainly wetted by oil ore is mainly wetted by oil And gang is mainly wetted by water next line This method is used This method is used for the separation of Sulfide ores Mildi and I don't know Sulfide ores for example We can have pbs. What is the name of this sulfide? I've given it now Cu f e s 2 Copper pyrite, okay Zns Is zinc blend pbs is galena. Okay. Must remember this name important This is galena This is zinc blend. This is copper pyrite Okay, must remember this Okay Mainly for sulfide ores this information on this information they have asked question in the exam Okay, froth flotation we use for sulfide ores mainly Okay, so what we do in this process? Write down a suspension of a suspension of a suspension of finely powdered ore with water is made right A suspension of finely powdered ore with or with water is made This is called slurry. Okay. I'm in just in notational write down. We have that finely powdered ore We add water in it And this suspension or the mixture that we have We call it as slurry slu double r y slurry in this slurry. We also add some Some what we get what we say some froth um Some stabilizers we add into this. Okay, so in this slurry We add various stabilizers, which we call it as additives right So in this one, I'll just in notational write down like this in this slurry. We add froth stabilizers Which helps in the forming of froth Froth stabilizers we also add some amount of collectors in this slurry Collectors one second Some amount of collectors in this slurry So froth stabilizers what all compounds we use for this? This one is important This you must keep in mind for stabilizing froth. We use compounds like aniline Aniline we use chrysol Etc as froth stabilizers important right collectors Mainly we use the salt of ethyl xanthate One example is sodium ethyl xanthate sodium ethyl Xanthate we use as collectors the formula you see for sodium ethyl xanthate We have this uh sodium ethyl xanthate We have ch3 ch2 it is ethyl O C double bond S instead of O we have S here S minus Na plus this is sodium ethyl xanthate I'll show you the diagram also for this the picture that we have Right, so what we use As the froth stabilizers you also copy down like this only okay in notation because if you're going to write down line by line It'll take a lot of time Froth stabilizers is this we use an example and lean and chrysol we have apart from this In order to form froth, okay in a good amount of froth in order to form We also add some oil into this Which we call it as pine oil Okay, so we add which we we call it as frothing agents, okay, which can form Froth, okay, so it is a frothing agent. We have Mainly we use pine oil for this purpose We don't have much example only this much you need to memorize So pine oil we add in order to form good amount of froth To stabilize froth we add aniline chrysol and we use some collector that is sodium ethyl xanthate Fatty essence also we can use as collectors Okay, so this uh, you know a collector that we have it, you know It enhance the non-weighting ability Of mineral particles in presence of character our collectors Our weighting ability decreases for mineral particles So this is the few things we add into this one a small point again you write down Write down in this suspension One more additive One more additive Which is known as Which is known as activators Or depressant two terms we have we all write down here We can use activator activators or depressant activator or depressant Is added activator or depressant is added In order to use this method for non-sulfide ore also So activator is what activator is The compound which improves the floating characteristics And is opposite of activator is depressant. Okay activators improves the floating characteristics Of ore improves the floating characteristics of ore And the one which reduces the floating characteristics Is depressant Reduces the floating characteristics depressant Okay example of activator one example we have write down it is lead sulphate Pb so forth Lead sulphate here we have nacn kcn nacn kcn we can write okay look at the diagram for this the figure that we have We have froth flotation this Okay So we have this paddle here Which we can rotate in order to form the froth Because everything if you make simple when in water if you add detergent right you have to mix it properly So that the froth forms correct same thing we have here we have an arrangement of Mixing the mixture over here paddle we rotate This is the blade we have and hence the mixture, you know mix properly and forms froth If froth is not forming will add pine oil in order to get more amount of froth right to serve the purpose right so Or we have an inlet over here to put ore into this and oil and then we'll mix it will forms or will form this froth Which we can take it out or filter it out Okay, air also mix over from this point We have an arrangement of low air also into this mixture in order to form froth again Okay, the same purpose we have here mineral froth. We can filter it out from this and we'll get the Concentrated ore over here. This is the arrangement of froth flotation. Okay, so this method we have Till now we discussed this under concentration of ore So we discussed handpicking we discussed hydraulic washing In that we discussed two methods, which is will flay table method and Hydraulic classifier. Okay, these two methods we discuss And then the third method we discuss in this electromagnetic separation Magnetic and non magnetic property. We have that roller law example You must have seen that and then the fourth one we have that is froth Flotation process. So four different methods we use for the concentration of ore Right now when the concentration is done Concentration of ore is done. You get the concentrated ore Then we have the next method which we call it as leaching One second So once we get the concentration concentrated ore We have the next step For the purification and that is the third term we have the third step we have That is leaching leaching. We also call it as Hydro metallurgy Hydro metallurgy or leaching both are the same thing Okay, right down it involves I'll write on it and leaching right down It involves the treatment of It involves the treatment of finely powdered ore finely powdered ore with a suitable reagent with a suitable reagent like Acid base any reagent we can use we can use acid base Any other chemical reagent we can use right down acid we can use for this purpose base or Other reagents chemical reagents we can use for this purpose And we choose this reagent in such a way In such a way that this reagent can dissolve ore But not the gang or impurities, okay So it involves the treatment of finely powdered ore with a suitable reagent Which can dissolve? Which can dissolve? What ore? But not the gang This is the condition we have right down the metal the metal Can be obtained after this When we dissolve this reagent we'll get the salt of metal from which it can be obtained by Different methods like electrolysis another thing, right the metal can obtain by obtained from its salt from its salt by Electrolysis Okay, I will give you one example here For leaching method only one example we'll discuss like suppose we are having the leaching of leaching of bauxite ore Okay, bauxite ore We call it as Bayer's process. This name is also important Okay, Bayer's process So in bauxite or first of all what happens you have to keep this in mind that pure alumina obtained from The bauxite ore Right in Bayer's process In Bayer's process pure alumina That is l203 obtained from from the bauxite ore Pure alumina obtained from the bauxite ore Okay, generally what happens in bauxite the impurities present are We have ion oxide like Fe2O3 These are the impurities present in bauxite We have silica SiO2 the impurities present and titanium oxide TiO2 Now these are the facts, you know, you cannot do anything into it like what impurities are present that you have to memorize Okay, so in in bauxites all these impurities we have now this solution is mixed with the NaOH solution 40% NaOH solution we mix into this that is the base we are using suitable reagent, you know reagent is NaOH over here Right now this NaOH when added into this so l203 dissolves and convert into sodium meta-aluminate that is That is the you know complex compound of aluminum. I'll write down the formula here And other impurities are left behind So first of all this NaOH I'll write down the reaction here We have the solution of al203 the bauxite ore And all those impurities present into this when you are added with You add this NaOH solution into this. This is solid This is aqueous Right and obviously water we have here So it converts into 2 Na alOH 2 NaAlOH4 Aqueous this is the product we get right which in This is sodium meta-aluminate sodium meta-aluminate Which further on you know Electrolysis it converts into the next reaction we have al203 solid Plus the base we have OH- In presence of H2O. This is the ionic form. I am writing it down. This is the molecular form ionic reaction is this which is alOH4 Minus anyone you can write Okay, aqueous So could you please go back to the previous slide? Yeah Sorry after this Okay, so we get this right sodium meta-aluminate now this solution of sodium meta-aluminate is filtered and the filter is cooled Filter is cooled down and at a certain pH Right it is neutralized with carbon dioxide and aluminum hydroxide precipitated out here Okay, this aluminum hydroxide if I write down the reaction here alOH4 Negative charge in is diluted with CO2 it converts into al OH 3 So CO2 is circulated here, right? It does not take part in the reaction OH minus ion forms. Okay, and then this alOH whole price We heat this at high temperature more than 1000 around 1500 Kelvin Then it converts into solid alumina l203 solid And H2O goes out in this reaction So this is the leaching process we have we add base We get the salt of it this salt You know it is circulated with carbon dioxide forms Hydroxide here alOH whole price which on heating converts into alumina Similarly, we can have extraction of copper and other things also But everything is we don't have to do all this even this one is also not that important Sometimes they have asked questions on alumina. That's why I have taken this example Okay, I'll go back. Let's copy this down That's a thank you, sir Okay, so we have done this Concentration is done and then we have leaching. Okay When leaching is done So in leaching we mainly get mainly we get oxides of metal. You see we are getting alumina oxides of metal Now from this metal oxides you need to take metal you need to extract metal So what we do you you have to remove oxygen from this, correct? So next step is the reduction of the Of the concentrated ore after leaching we'll do the Reduction and reduction also we can do in two different way. Okay, both will discuss over here. So next step After leaching we have calcination calcination is I'm sorry leaching we have done after this thing Concentration of ore we have leaching after leaching we have reduction of the concentrated ore Production of of concentrated. Okay, write down metals are usually present Metals are usually present as Hydroxides Means you have metal hydroxides Or you have carbonates carbonates Or sulfides Mainly sulfides, etc. Okay So what we do If all these hydroxides carbonates sulfides we have So first we need to convert this hydroxide sulfides And carbonates into oxides Right, so from metal hydroxide We convert this into metal oxide metal carbonates Converts into metal oxides metal sulfides converts into metal oxides Why because we need to extract metal so it is always easier to extract metal from metal oxides right Then all other compounds due to the thermodynamic reason. Okay, it is you know easily Like feasibility of the reaction is Is Easier in comparison to the other carbonates sulfides or hydroxide that we have Okay, so one point you add in the last over here um write down to extract metal from its Compounds compounds means what I'm not giving you all the three words compounds means hydroxides carbonates and sulfides Okay to extract metal from its compounds it first the compound first converted into The metal oxides So this metal hydroxide sorry metal compounds are converted into metal oxides because Are converted into metal oxides because extraction of metal because extraction of metal Is easier is easier from Is relatively easier right now extraction of metal Is relatively easier From its oxides from its oxides Due to thermodynamic reason Due to thermodynamic reason Now, how do we convert? metal into metal hydrox sorry metal oxide Okay, all these hydroxides carbonates sulfides we have how do you convert this into oxides? So for that we have two methods One is we'll discuss under this one is calcination The first method in this a We have calcination write down It is the process in which It is the process in which The ore is heated strongly It is the process in which The ore is heated strongly The ore is heated strongly In absence or limited supply of air important this point is okay ore is heated strongly in absence or Limited supply of air that is calcination Okay, they've asked question on this information Okay, limited supply of air at a temperature at a temperature At a temperature comma lower than the melting point of the metal Means the temperature should not be more than the melting point because well in that case the metal also will be made will get melt Right, so temperature must be lower than the melting point and will heat strongly Okay, in absence or limited supply of air. So for example, you see this reaction if you have Uh, this compound Hydroxide of iron FeOH Whole thrice when you heat this you will get Fe2O3 oxide of metal and H2O will go out how much 3 H2O? right Hydrated or if you have so for example, you see bauxite or Al2O3 dot 2 H2O We again heat this strongly it converts into Al2O3 and H2O Okay, if you have carbonates like CaCO3 we get CaO Plus CO2 calcium oxide we get CO2 CaO we can also obtain from dolomite CaCO3 dot mg CO3 important this reaction is when you heat this you'll get CaO Plus mg O magnesium oxide and two molecules of CO2 So when you heat this in absence of air We'll get the oxide of metal So calcination is this Now the next second process in this reduction of concentrated ore One way is calcination other one is roasting other one is roasting in this the ore is heated strongly Is heated strongly In presence of air so previous one absence This one is presence of air Again at a temperature below the melting point excuse me Now So in this method what happens you see all the sulphide ore will be converted into the oxide Of metal okay, and that is what the purpose we have so The reaction is Suppose we have HGS This is the reaction we have Cu2s Plus O2 gives uh Cu2O 2 SO2 ZNS plus balanced reaction I'll write down 3 O2 gives 2 SO2 By this method we can also remove Write down by this method we can also remove I'll write down it we can also remove Non-metallic impurities non-metallic impurities like like arsenic antimony sulphur phosphorus etc All these non-metallic impurities we can remove So how it happens all these uh, you know non-metallic impurities converts into oxide and escapes volatile gas it forms So look at this reaction 4 AS arsenic plus 3 O2 It forms 2 AS 2 O3 Volatile gas it escapes into the atmosphere sulphur and oxygen Forms SO2 Escapes in the atmosphere Okay phosphorus O2 converts into P4 O10 Escapes in the atmosphere One last point it can also remove It can also remove water from From hydrated ores hydrated ores These are the uses we have for This method that is roasting done