OBJECTIVES
- Prepare CuSO4 exchanged clay dilutions from Cu2+ clay exchanged stock solution for atomic absorption
- Run absorption on all CuSO4 dilution samples prepared
Preparations For CuSO4 Clay Exchanged Solutions & Vacuum Filtration Procedures
Setup of a vacuum filtration system:
* Clean 250mL Erlenmeyer Filter Flask
* Large Buchner Funnel
* Whatman #42 Filter Paper
* Long Secure Rubber Hose
- Pour 20 mL of CuSO4 stock solution into a 100mL beaker with a stir bar
- As the solution stirs, measure out and add ~ 0.1 grams of NaMT clay and start the timer
- Time for ~ 1 min and then filter the solution using the vacuum filtration system setup
- Attach all parts of the apparatus to the vacuum filtrator system
- Place a piece of Whatman #42 filter paper in the Buchner Funnel
- Turn on the vacuum filtrator system
- Check the suction rate to ensure that enough pressure is applied
- Pour in the 1 min. exchanged NaMT CuSO4 aqueous solution
- Allow the vacuum filtration to continue until the clay is completely dry
- Collect the aqueous filtrate solution and place it in a labeled small closed cap vial
- Collect the soil filtrate on the filter paper and scrape it into a small labeled metal pan
- Place metal pan with the soil filtrate in the oven to dry for ~ 1 day
- Wash all glassware and equipment first with H2O and then with acetone for later use
REPEAT THE PROCEDURE ABOVE FOR TIME PERIODS OF 5 MIN & 10 MIN FOR EACH SAMPLE
REPEAT THE PROCEDURE ABOVE FOR THE 100% CEC NaMT, 50% CEC NaMT, & 2:1 Fe3O4 CLAYS AS WELL
Atomic Absorption CuSO4 Clay Exchanged Dilutions & Calculations
CuSO4 Dilution Standards
12mL 7.4 ppm CuSO4 requires:
(636ppm CuSO4)V1 = (7.4ppm CuSO4)(12mL)
V1 = 0.140mL
12mL 10 ppm CuSO4 requires:
(636ppm CuSO4)V1 = (10ppm CuSO4)(12mL)
V1 = 0.189mL
- Total of 18 dilutions were made for every time interval (1 min, 5 min, and 10 min) during the NaMT, 50% CEC NaMT, and 100% CEC NaMT clay exchanges.
Atomic Absorption Results
Atomic Absorption Data and Calibration Curve Data from AA wizard:
Cu
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'
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'
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'
|
Action |
Sample ID |
True Value (ppm) |
Conc. (ppm) |
Abs.
|
AUTOZERO |
|
|
|
|
STD |
STD 1 |
1 |
|
0.0054
|
STD |
STD 2 |
5 |
|
0.0118
|
STD |
STD 3 |
10 |
|
0.6531
|
STD |
STD 4 |
20 |
|
1.0516
|
STD |
STD 5 |
25 |
|
1.1173
|
STD |
STD 6 |
30 |
|
1.1773
|
STD |
STD 7 |
40 |
|
1.2726
|
STD |
STD 8 |
50 |
|
1.3179
|
UNK1 |
7.4ppm NaMT 1min |
|
7.5551 |
0.3993
|
UNK2 |
10ppm NaMT 1 min |
|
10.9678 |
0.4959
|
UNK3 |
7.4ppm NaMT 5 min |
|
7.0393 |
0.3847
|
UNK4 |
10ppm NaMT 5 min |
|
10.6639 |
0.4873
|
UNK5 |
7.4ppm NaMt 10 min |
|
4.2696 |
0.3063
|
UNK6 |
10ppm NaMT 10min |
|
7.2478 |
0.3906
|
UNK7 |
7.4ppm Fe3O4 1min |
|
46.4402 |
1.5
|
UNK8 |
10ppm Fe3O4 1 min |
|
44.9883 |
1.4589
|
UNK9 |
7.4ppm Fe3O4 5min |
|
39.7598 |
1.3109
|
UNK10 |
10ppm Fe3O4 5min |
|
43.9567 |
1.4297
|
UNK11 |
7.4ppm Fe3O4 10min |
|
39.841 |
1.3132
|
UNK12 |
10ppm Fe3O4 10min |
|
39.9647 |
1.3167
|
UNK13 |
7.4ppm CEC100% 1min |
|
11.1939 |
0.5023
|
UNK14 |
10ppmCEC100% 1min |
|
16.5283 |
0.6533
|
UNK15 |
7.4ppm CEC100% 5min |
|
9.5123 |
0.4547
|
UNK16 |
10ppm CEC100% 5min |
|
15.4473 |
0.6227
|
UNK17 |
7.4ppm CEC100% 10min |
|
8.4171 |
0.4237
|
UNK18 |
10ppm CEC100% 10min |
|
15.7794 |
0.6321
|
UNK19 |
7.4ppm CEC 50% 1min |
|
10.5191 |
0.4832
|
UNK20 |
10ppm CEC 50% 1min |
|
14.7443 |
0.6028
|
UNK21 |
7.4ppm CEC 50% 5min |
|
9.802 |
0.4629
|
UNK22 |
10ppm CEC 50% 5min |
|
15.3449 |
0.6198
|
UNK23 |
7.4ppm CEC 50% 10min |
|
10.4449 |
0.4811
|
UNK24 |
10ppm CEC 50% 10min |
|
15.0057 |
0.6102
|
Notes
- Dilution standards listed above for CuSO4 are incorrect and inaccurate due to miscalculations of stock solution concentrations
CuSO4 stock solution = 1283 ppm
- New original standards prepared were increasingly high in concentration; therefore, CuSO4 standards, 5-20ppm, must remade
- All 2:1 α-Fe3O4 samples remade and tested because the solutions were diluted with CuSO4 instead of distilled H2O
- Due to various errors regarding concentrations the calibration curve created was inaccurate
- AA needs to be run again
- IMPORTANT NOTE: Between each sample, distilled H2O must be run to clear out all left over residue from the previous sample. Allow the absorption value, while running distilled H2O, to reach the value of 0 on the computer before running another concentrated CuSO4 sample
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