Traditional Analysis by Gravimteric & Volumetric Analysis of Cement or Clinker for Determination of SiO2,Al2O3 ,Fe2O3 & Cao & MgO Dear Sir,
I have few Queries On Gravimteric & Volumetric Analysis of Cement or Clinker
Question Detail*On Gravimteric & Volumetric Analysis of Cement or Clinker for Determination of SiO2,Al2O3 ,Fe2O3 & Cao & MgO
1. Dear Sir We adopting the Method for Determination of SiO2 as follow : 0.5 gm of sample + 0.5 gm NH4Cl Mix Vigourly till smell of NH3 comes then kept for 30 - 40 Min of Slow Hot Plate (70 Deg. Celsius) then Filter thorugh Whatmann Filter Paper42 . My Question is "what "what is the purpose of NH4Cl addition in this Analysis " 2. Further in R2O3 Determination what will happened if We added more 1:6 NH4OH on Analysis after formation of Precipitate of R2O3 & Also why HNO3 is added , R2O3 Pricipitate get form without adding it.
3.Can You provide Chemical Reaction involved in Gravimteric A nalysis of Cement or Clinker for the determination of SiO2,Al2O3 ,Fe2O3 & Cao & MgO.
4.Can You provide Chemical Reaction involved in Gravimteric & Volumetric Volumetric Analysis of Cement or Clinker Clinker by Rapid Cao Method : 0.5 gm sample + 5-10 ml Conc HCL then Boil & add methyl red after that 1:6 NH4OH till Yellow Color appear then Oxalic acid added then 7% Amm onium Oxalate added & kept for digestion for 30 -40 Min on Slow Hot Plate ,Filter thorugh 41 WFP & 10-20 ml H2SO4 & Titrate against KMnO4 in Hot Condition 5.Role of Oxalic Acid in Rapid CaO Method & Also Give Chemical Reaction involved in it
6.Is any Rapid MgO Method for Mgo Determination.
7.Give Chemical Reaction involved in TC & MC & also Method.Theoretical Calculus is also needed
8.In LSF formula from which calculation of we get 2.8 part of SiO2 ,1.2 part of Fe2O3 & 0.65 part of AL2O3 & also 0.7 SO3.
9.How to do more than 5 component Raw Mix design.Please provide me Calculus or Suggest in excel.
10. Give Volumetric Method for Cement or Clinker Analysis
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Regards
Ravi Chauhan +918007679752
re Traditional Analysis by Gravimteric & Volumetric Analysis of Cement or Clinker for Determination of SiO2,Al2O3 ,Fe2O3 & Cao & MgO Hello Ravi,
To answer your questions;-
1. Dear Sir We adopting the Method for Determination of SiO2 as follow : 0.5 gm of sample + 0.5 gm NH4Cl Mix Vigourly till smell of NH3 comes then kept for 30 - 40 Min of Slow Hot Plate (70 Deg. Celsius) then Filter thorugh Whatmann Filter Paper42 . My Question is "what is the purpose of NH4Cl addition in this Analysis"
Could you please clarify the method. At what stage is water added in the example above? Normally hydrochloric acid is used to dissolve the clinker minerals and gypsum in the determination of free silica (insoluble residue) in clinker or cement, not ammonium chloride.
2. Further in R2O3 Determination what will happened if We added more 1:6 NH4OH on Analysis after formation of Precipitate of R2O3 & Also why HNO3 is added , R2O3 Pricipitate get form without adding it.
R2O3 is composed of Al2O3 + Fe2O3. Al2O3 is amphoteric (ie it will dissolve in an excess of either acid or base.) NH4OH is strongly basic. So, if you added too much NH4OH, it would dissolve some of the Al2O3 out of the R2O3 precipitate giving you a low result for Al2O3.
Please clarify at what point in the test HNO3 is used?
3.Can You provide Chemical Reaction involved in Gravimteric Analysis of Cement or Clinker for the determination of SiO2,Al2O3 ,Fe2O3 & Cao & MgO.
There are many reactions involved in each analysis, please be more specific.
4.Can You provide Chemical Reaction involved in Gravimteric & Volumetric Analysis of Cement or Clinker by Rapid Cao Method :
0.5 gm sample + 5-10 ml Conc HCL then Boil & add methyl red after that 1:6 NH4OH till Yellow Color appear then Oxalic acid added then 7% Ammonium Oxalate added & kept for digestion for 30-40 Min on Slow Hot Plate ,Filter thorugh 41 WFP & 10-20 ml H2SO4 & Titrate against KMnO4 in Hot Condition 5.Role of Oxalic Acid in Rapid CaO Method & Also Give Chemical Reaction involved in it
Oxalic acid is added to the dissolved c ement or clinker to precipitate insoluble calcium oxate from calcium c hloride by the following equation;-
CaCl2 + (COOH)2 ----> Ca(COO)2 + 2HCl
Ammonium oxalate is added as a buffer to keep the calcium oxalate from redissolving in the digestion stage. The Calcium oxalate precipitate is filtered and redissolved in sulphuric acid and the oxalic acid which is formed is titrated with potassium permanganate. This titration is an oxidation/reduction reaction in which the intense red colour of the permanganate itself is used as the indicator eg;-
Calcium oxalate dissolves in sulphuric acid;-
Ca(COO)2 + H2SO4 ------> (COOH)2 + CaSO4
Permanganate oxidises oxalic acid to CO2 and H2O while itself being reduced into potassium and manganese sulphates;-
5 (COOH)2 + 2 KMnO4 + 3 H2SO4 ------> K2SO4 + 2 MnSO4 + 8 H2O + 10 CO2
6.Is any Rapid MgO Method for Mgo Determination.
MgO can be analysed by EDTA titration of the filtrate from the "Rapid CaO" test above. Since all of the CaO is filtered out as insoluvle calcium oxalate, the MgO remains in the filtrate and can be titrated directly with EDTA. See; http://www.ncbi.nlm.nih.gov/pubmed/18965740
7.Give Chemical Reaction involved in TC & MC & also Method.Theoretical Calculus is also needed
Please clarify... what is TC & MC?
8.In LSF formula from which calculation of we get 2.8 part of SiO2 ,1.2 part of Fe2O3 & 0.65 part of AL2O3 & also 0.7 SO3.
Actually it's the other way around;- 1.18 * Al2O3 and 0.65 * Fe2O3. These factors are de rived from the phase equilibria of the CaO-SiO2-Al2O3-Fe2O3 system at the point where free CaO first starts to form. ie where LSF =1. A discussion on this subject can be found here;- http://www.cemnet.com/Forum/thread/108168/lsf-formula.html http://books.google.com.au/books?id=1BOETtwi7mMC&pg=PA56&lpg=PA56&dq=derivation+of+LSF+formula&sourc e=bl&ots=6XxcMA1VxB&sig=ZGdFf-EOuYpQVneAxDrTC7bKB8E&hl=en&sa=X&ei=oqhsUf-2K-TiAey3oCQBQ&ved=0CE0Q6AEwBA#v=onepage&q=derivation%20of%20LSF%20formula&f=false
The 0.7 SO3 applies only to the application of the LSF formula to cement, to allow for the CaO combined with SO3 in gypsum. ie (CaO=56, SO3=80, 56/80 =0.7)
9.How to do more than 5 component Raw Mix design.Please provide me Calculus or Suggest in excel.
This is a very complex and time consuming undertaking. So, unless somebody has already written such a raw mix design program, you will have to work it out for yourself using simultaneous equations,... methods for this can be found on the internet. eg ;http://www.idomaths.com/simeq.php
Regards.
Ted.
Hello Ravi,
I have researched and found enough information to attempt an more detailed explanation on your question #8;-
8.In LSF formula from which calculation of we get 2.8 part of SiO2 ,1.2 part of Fe2O3 & 0.65 part of AL2O3 & also 0.7 SO3.
Very simply speaking, LSF is the theoretical point in the C-S-A-F system where there is just enough CaO present to react completely to form C3S from C2S at 1450oC under equilibrium conditions.
At this point the C 2S content of the clinker would theoretically be = 0. Therefore you would only expect C 3S, C3A and C4AF to exist at this point on the C-S-A-F quaternary phase diagram. While this is certainly true for C 3S and C4AF, it turns out that a significant amount of SiO2 is incorporated into the C3A at this point and its actual composition is closer to C 3.31AS0.39 Therefore, assuming that the minerals existing at the point of lime saturation are C 3S, C4AF and C3.31AS0.39 we can the say that the sum of the oxides, SiO 2, Fe2O3 and Al2O3 in these minerals, expressed as a molar fraction of the CaO, will be equal to unity. Now, given that the minerals existing at the point of lime saturation are C 3S, C4AF and C 3.31AS0.39 we can calculate the molar weight ratios of SiO 2 /CaO, Fe2O3 /CaO and Al2O3 /CaO in these minerals. Below is the worked example for Al2O3and Fe2O3 in C4AF;Al2O3 / CaO
= 102/(4*56) = 102/224 = 0.455
Fe2O3 / CaO = 159.7/(4*56) = 159.7/224 = 0.713 Using the same method we can calculate the molar weight ratios for all of the minerals present. These are shown in the table below;-
Mineral -->
C3S
C4AF
C3.31AS0.39
SiO2 / CaO
0.357
0
0.126
Al2O3 / CaO
0
0.455
0.549
Fe2O3 / CaO
0
0.714
0
Let the relative multipliers for SiO 2, Al2O3 and Fe2O3 required for lime saturation be x, y and z respectively. Now, using the molar weight ratio information in the table above, we can write three equations (one for each mineral) which are all true at the lime saturation point;The three equations take the form;-
x * SiO2 /CaO + y * Al 2O3 /CaO + z* Fe2O3 /CaO = 1 and are;-
For C3S;-
x * 0.357 + y * 0 + z * 0 = 1
(Eq.1)
For C4AF;-
x * 0 + y * 0.455 + z * 0.714 = 1
(Eq.2)
For C3.31AS0.39;-
x * 0.126 + y * 0.549 + z * 0 = 1
(Eq.3)
Solving Eq.1 we have;-
x * 0.357 + y * 0 + z * 0 = 1
x * 0.357 = 1
x = 1 / 0.357
x = 2.8
(Which is the LSF coefficient for SiO 2)
Simplifying Eq.2 and Eq.3 we get;-
y * 0.455 + z * 0.714 = 1
(Eq.3)
and
x * 0.126 + y * 0.549 = 1
Substituting for x in Eq.4 we have;-
2.8 * 0.126 + y * 0.549 = 1
0.353 + y * 0.549 = 1
y = (1 - 0.353) / 0.549
(Eq.4)
y = 1.18
(Which is the LSF coefficient for Al 2O3)
Now, substituting for y in Eq.3 we get;-
1.18 * 0.455 + z * 0.714 = 1
0.537 + z * 0.714 = 1
z = (1 - 0.537) / 0.714
z = 0.65
(Which is the LSF coefficient for Fe 2O3)
This means that;-
2.8 * SiO2/CaO + 1.18 * Al 2O3 /CaO + 0.65 * Fe 2O3 /CaO = 1 or;-
2.8 * SiO2 + 1.18 * Al 2O3 + 0.65 * Fe 2O3 = CaO or;-
CaO
______________________________
2.8 * SiO2 + 1.18 * Al 2O3 + 0.65 * Fe 2O3
Regards,
Ted.
= 1
(ie. The lime saturation factor)
Re: Cement Fineness and Workability Hello Dilip,
I received the paper you emailed me and have sent you a reply. But for the benefit of others reading this thread I have copied my reply to you here;-
I think what this paper is saying is that although finer cement causes an increase in both the measured consistency and water demand of cement paste. There is another factor to take into account when considering workability of concrete. This factor is the fineness of the cement particles themselves and their positive effect on concrete workability. eg
"As per our findings, with an increase in the fineness of cement, both consistency of cement and workability of concrete increase. Increase in consistency means increase in water demand to get cement paste of standard consistency while increase in workability means increase i n flowability at the same water/cement ratio. In other words decrease in water demand to get the same workable concrete. Apparently it looks to give a controversial situation. But it can be more easily understood by considering that workability of concrete determines the amount of work done to achieve a certain value of compaction. When the water is added, it wets the surface of particles an d reduces the interparticle frictional resistance. When fineness of cement increases beyond a certain particle size, the particles of cement itself starts acting as lubricants in the c oncrete. Therefore, the particles flow and less effort/work is required for compaction of concrete i.e. the water demand decreases to obtain the same degree of workability."
So, it is not really a contradiction. It is just that a factor other than water content is coming into play with respect to workability of concrete... the lubricating properties of the fine particles of cement themselves.
Regards, Ted.
