Analysis of the Codorus Creek
Quantitative Analytical Chem.
Fall 2002
Agenda
• Background– Purpose of study– Sampling scheme– Major Polluters– Clean-up Acts
• Chloride Analysis
• Sulfates
Agenda Continued
• Sulfites
• Calcium and Magnesium
• Nitrates
• Various Metals (silver, mercury, and lead)
Codorus Creek Study
• Purpose of Study– Use various analytical techniques from
previous methods• Titrimetric, gravimetric, and UV-Vis
– Determine amounts of analyte in East and West Branches and Main Branch of Codorus Creek
Where Our Water Comes From
• http://www.yorkwater.com/
Sampling Scheme
• Sampled above and below PH Glatfelter (West Branch)– 616 Bridge
• Sampled above and below Indian Rock Dam (East Branch)– Ridge View Rd.– Reynolds Mill Rd.
• Sampled from the South Branch• Sampled from Waterway Bar and Grill, Philadelphia
St.• Sampled from Indian Rock Campground
Sampling Scheme Continued
• Make standard curves
• Test samples
• Compared values with the spec. (Hach kit)
• Spiked samples to determine % recovery
Major Industries That Pollute
• Brunner Island
• PH Glatfelter
• Baker Refractories
• Lehigh Portland Cement
Other Pollution
• Farmland– Nitrates
• Urban/Storm Runoff
• Industrial Waste
• Municipal Waste– Source:
Cleanup Acts
• Codorus Creek Cleanup June 2002– Source: www.pawatersheds.org
Analysis of Chloride
Testing performed by Kim and Jamie
Chloride Analysis
• Method from Quantitative Chemical Analysis by Daniel C. Harris
• Used in Class previously
• Found on page 859-860 of text
• Acceptable levels of Chloride are 0.01 ppm– www.epa.gov
Method
• Standard Curve– 0.03 g Dextrin to 50 mL of known conc. Plus 5
drops of dichlorofluorescein• 1ppm, 0.8 ppm, 0.6 ppm, 0.2 ppm, 0.05 ppm, and
0.01 ppm of chloride
– Titrated with 4 g of AgNO3 dissolved in 200 mL DI water
– Titrated until pink endpoint
Standard Curve of Chloride
0
10
20
30
40
50
60
70
80
0 0.2 0.4 0.6 0.8 1 1.2
ppm
mL A
gNO3
Samples
• 50 mL of sample put into Erlenmeyer Flask with 0.03 g Dextrin
• Added 5 drops of dichlorofluorescein• Titrated with AgNO3 to a pink endpoint
Location PPM By Spect
PPM By Spect
Philadelphia St.
0.227 mg/L
0.23 mg/L
0.041 mg/L
0.07 mg/L
Indian Rock Dam
0.066 mg/L
0.07 mg/L
0.022 mg/L
0.02 mg/L
West Branch (Below P.H. Glatfeder)
0.222 mg/L
0.24 mg/L
0.223 mg/L
0.25 mg/L
East Branch Above
0.010 mg/L
0.05 mg/L
0.028 mg/L
0.03 mg/L
East Branch Below
0.120 mg/L
0.13 mg/L
0.222 mg/L
0.21 mg/L
South Branch
0.01 mg/L
0.02 mg/L
0.036 mg/L
0.04 mg/L
Titration and Spec. Data
Location PPM (by spec)
Recovered amount
Percent Recovery
Philadelphia St.
0.07 mg/L Not enough sample
Indian Rock Dam
0.02 mg/L 0.988 96.7 %
West Branch (Below P.H. Glatfeder)
0.25 mg/L 1.211 96.8 %
East Branch Above
0.03 mg/L 0.986 95.7 %
East Branch Below
0.21 mg/L 1.194 98 %
South Branch 0.04 mg/L 0.987 94.9 %
Spikes
Results
• Different levels of chloride at different points along the Codorus Creek
• Highest levels 0.227 ppm– Philadelphia St.
– Stagnant water
– Shopping cart
• Lowest levels– South Branch and East Branch above Glatfelter
• 0.01 ppm---acceptable limits
Results….
• Spike Recovery– Average= 96.42% – 1 ppm spikes
Error
• Color of endpoint– Pinks hard to determine– Dull vs. bright
• Samples– Occasionally 1st sample turned right away– Other 3 trials were okay
Error…
• Water collection– After periods of rain
• Dilution errors– Pipetting
• Titration errors– Color of endpoint
• Hints of green when it turned pink– When poured down the drain
Sulfates
Testing performed by Rob and Howie
Primary Source of Sulfates
Worst Case Offenders - 1999
• Brunner Island – 71,188 tons
• PH Glatfelter – 6,521 tons
• Baker Refractories – 3,609 tons
• Lehigh Portland Cement – 1,368 tons
Sulfate Wet Deposition
Hazards of Sulfates In Water
• Below 250 ppm no direct harm to people
• Causes acidification– Kills fish– Decreases biodiversity– Causes chronic stress– At pH 5.0 most fish eggs can’t hatch
Effects of pH
Long-Term Trend in Stream Chemistry
Sulfate Analysis: Baseline
• 90 mL distilled water
• 10 mL BaCl2
• Take 20 mL off top
• 3 drops calmagite
• Titrate with EDTA
• Get Standard Zero
Sampling Procedure
• 90 mL Sample
• 10 mL BaCl2
• Allow to precipitate overnight
• Pull 20 mL off top
• 3 drops calmagite
• Titrate with EDTA
• Average Titrations
Formulas
• Standard Zero – Average Titration
• Divide by 1000
• Multiply by .0434 M EDTA
• Multiply by mw SO4 (96)
• Divide by .09 L (Amount of water sample)
• Get ppm
Spikes
• 3 different distilled water samples (.1 L)
• Added sodium sulfate (mw = 142.04 g)– #1 - .0087 g = 58.8 ppm Got 48.2 ppm– #2 - .0493 g = 333.4 ppm Got 315.7 ppm– #3 - .1194 g = 807.5 ppm Got 733.6 ppm
Results Trial 1
Location Test Kit (ppm) Titration Results (ppm)
Below PHG 80 26.39 / 51.0
Below Dam 37.03
Indian River 9.26
Above Spring Grove
11 6.02
Philadelphia St 10.65
Results Trial 2
Location Test Kit (ppm) Titration Results (ppm)
South Branch 6 18.5
Below Dam 7 6.02
Indian River 19 18.5
Above Dam 6 9.3
Sources of Error
• Determination of titration endpoint
• Titration errors
• Precipitation time
• Measurements
• Quantity of original sample
• Testing performed by John
Sulfitesin the
CODORUS!
KI-KIO3 volumetric method
Performed by John
What are sulfites used for?
• Used to sanitize and preserve foods
• Used in the wine industry as an antioxidant and antimicrobial
• Dehydration of fruits and vegetables
• Wood pulping and paper making
Effects of sulfites
• Causes allergic reactions in asthmatics
• FDA and ATF have mandated that sulfites in foods at levels of 10 ppm or higher be reported on labels
Procedure
• Standard potassium iodide-iodate titrant(diluted 100 times from procedure found in Standard Methods for Water and Wastewater)
• Starch indicator
KI-KIO3
• ~.4400 g anhydrous KIO3
• 4.35 g KI
• .0310 g sodium bicarbonate
• Place in 1000 ml volumetric flask and fill to the mark
Starch indicator
• Boil 100 ml water
• Weigh out 1 g of starch and place in 10 ml of water
• Pour paste into boiling water
• Boil until clear
• Must be made before every class
Put it all together!
• In 250 ml flask
• 1 ml sulfuric acid
• .1 g sulfamic acid
• 50 ml water sample
• 1 ml starch indicator
• Titrate with KI- KIO3 until blue
Calculation of Sulfites
• Used known amounts of sodium sulfite to create calibration curve
• Calculated amount of sulfites from equation by plugging in the amount of titrant used
Data
• Minimum detectable limits 2 mg/L = 2 ppm
• All data came out negative except Philadelphia street from both days and the east branch from day two
• Most data below minimum detectable limits
Day 1Trial g sulfamic ml KI-KIO3 ppm
Philadelphia 1 0.1014 10.3 0.962 0.1006 10.6 1.923 0.1004 11 3.2
Day 2Trial g sulfamic ml KI-KIO3 ppm
Philadelphia 1 0.1017 10.1 0.322 0.1014 10.3 0.963 0.1004 9.9 NA
East BranchAbove Dam 1 0.1007 10.7 2.24
2 0.1007 10.4 1.283 0.1009 9.9 NA
East Branchbelow dam 1 0.1004 9.8 NA
2 0.1005 10.1 0.323 0.1024 10.3 0.96
Data
Results
• Day 1– Philadelphia Street
• .96 ppm
• 1.92 ppm
• 3.20 ppm
• Day 2– East Branch below
• .32 ppm• .96 ppm
– Philadelphia Street• .32 ppm• .96 ppm
– East Branch above dam• 2.24 ppm• 1.28 ppm
Spikes
• Added a 2.508 x 10-7 M solution of sodium sulfite
• About doubled the level of sulfites in the water
• Made all of the samples above the detectable limit
Conclusions
• The levels of sulfites in the water is below detectable levels
• Error– Calibration curve– Detecting endpoint
Ca2+ and Mg2+ Concentrations
By
Jennie Waughtel
And
George Collins
Points of Interest
There are no minimum or maximum standards set by the EPA
Raw Water Data from The York Water Company
Ca concentration (ppm):
Mg Concentration (ppm):
Method of Analysis• EDTA Titration
– Reagents Needed
– EDTA Solution• 0.6 g Na2H2EDTAdihydrate dissolved in 500ml distilled H20
– Calmagite indicator– 0.5 M NaOH
• 5 g NaOH dissolved in 250 ml distilled H20
– Buffer (pH 10)
• 142 ml of 28% aqueous NH3 to 17.5 g of NH4Cl• Dilute with distilled H2O to 250 ml• Adjust pH using 1M HCL• Target pH 10: Actual pH 10.03
Method of Analysis
• Procedure for total Ca2+ and Mg2+ ppm
– Pipet 50ml of sample into 250ml flask
– Add 3ml by pipet of Buffer Reagent
– Add 6 drops of Calmagite indicator
– Titrate with EDTA solution until the wine red color changes to blue
Method of Analysis
• Procedure for total Ca2+ ppm
– Pipet 50ml of sample into 250ml flask
– Add 30 drops (1.1ml) of NaOH Reagent and wait 2 min to precipitate Mg(OH)2
– Add 6 drops of Calmagite indicator
– Titrate with EDTA solution until the wine red color changes to blue
Results of Analysis• Ca2+ Concentrations
– East Branch above Lake Redman : 28.485 ppm– East Branch below dam : 41.289 ppm– West Branch above Spring Grove : 43.881 ppm– West Branch below Glatfelter : 88.141 ppm– Indian Rock Dam : 55.705 ppm– Philadelphia Street : 48.655 ppm– South Branch : 32.816 ppm
– Overall average : 48.402 ppm
Ca2+ Concentrations (ppm)
28.485
41.28943.881
88.141
55.705
48.655
32.816
48.402
28.00030.00032.00034.00036.00038.00040.00042.00044.00046.00048.00050.00052.00054.00056.00058.00060.00062.00064.00066.00068.00070.00072.00074.00076.00078.00080.00082.00084.00086.00088.000
East Branch aboveLake RedmanEast Branch belowDamWest Branch aboveSpring GroveWest Branch belowGlatfelterMain Creek at IndianRock DamMain Creek atPhiladelphia StreetSouth Branch
Overall Average
Results of Analysis• Mg2+ Concentrations
– East Branch above Lake Redman : 15.786 ppm– East Branch below dam : 15.689 ppm– West Branch above Spring Grove : 8.738 ppm– West Branch below Glatfelter : 48.210 ppm– Indian Rock Dam : 24.850 ppm– Philadelphia Street : 28.423 ppm– South Branch : 18.579 ppm
– Overall average : 22.727 ppm
Mg2+ Concentrations (ppm)
15.78615.689
8.738
48.210
24.850
28.423
18.579
22.727
7.0009.000
11.00013.00015.00017.00019.00021.00023.00025.00027.00029.00031.00033.00035.00037.00039.00041.00043.00045.00047.00049.000
East Branch aboveLake RedmanEast Branch belowDamWest Branch aboveSpring GroveWest Branch belowGlatfelterMain Creek at IndianRock DamMain Creek atPhiladelphia StreetSouth Branch
Overall Average
Background
EPA Standards
Monitoring water ways
Health effects
Previous Studies
Iowa study
Studies on Lower Susquehanna Basin
EPA study
Procedure • Pipet 10ml. of sample into an Erlenmeyer flask
• Add 2ml. of 30% salt solution, which was previously prepared using 300g. NaCl and diluted in 1L of water
• Cool the sample in an ice bath for approximately 5 minutes
• Once cool, pipet 10ml. of 13N (6.5M) Sulfuric acid solution into the flask
• The Sulfuric acid solution prepared by diluting 180.55ml of 18M Sulfuric acid to 500ml. of water
• Add 0.5ml Brucine reagent, which is prepared by dissolving 1g. brucine sulfate and 0.1g. sulfanilic acid in 70ml. of water
• Place clear mixture into a water bath and boil for approximately 25-35 minutes
• After heating, the mixture should exude a noticeable pale yellow color (which is a sign of nitrate present in solution)
• Using UV-VIS instrument test samples for absorbance
Qualitative Analysis
UV-VIS Spectrophotometer was used to measure absorbance . Matter can capture electromagnetic radiation and convert the energy of a photon to internal energy. This process is called absorption. Energy is transferred from the radiation field to the absorbing species. We describe the energy change of the absorber as a transition or an excitation from a lower energy level to a higher energy level. Since the energy levels of matter are quantized, only light of energy that can cause transitions from one level to another will be absorbed.So by measuring absorbance at specific wavelength we can determine Nitrate concentration in our sample.
Qualitative Analysis
After blanking the instrument with distilled water sample we ran a 722ppm Nitrate standard. We observed that at 352nm absorbance was higher than that at 410nm. After running a series of standards ranging from low concentration to high concentration we constructed a calibration curve. Calibration curve showed that absorbance at 410 is more stable and therefore has a better correlation of absorbance vs. concentration.
Calibration Curve
Next step was to create a calibration curve. We ran several standards and then plotted absorbance vs. concentration of nitrate in our samples.
Calibration Curve
y = 0.0005x + 0.0083
R2 = 0.9802
0.00E+00
5.00E-02
1.00E-01
1.50E-01
2.00E-01
2.50E-01
0 100 200 300 400
Concentration of Nitrate (ppm)
Abs
orba
nce
Quantitative Analysis
Sample ppm AbsorbanceS. Branch A 13.20 1.49E-02S. Branch B 10.00 1.33E-02S. Branch C 12.00 1.43E-02S. Branch Avg. 11.73Spike A 166.00 9.13E-02Spike B 161.80 8.92E-02Spike C 160.20 8.84E-02Spike Avg. 162.67
Spike ppm Added: 160.44% Recovery: 94.07%
Below PHG 230.7 ppmAbove S.G. 52.0 ppmPhilladelphia St. 10.0 ppmBelow Dam N/DIndian R.Dam N/DE.B. Above Redman 72.8 ppm
Sources of Error
• Brucine reagent very unstable (to be stored at 5 F at all times)
• Errors in preparation of brucine-sulfanilic acid reagent, specifically when measuring precisely 0.1 g of sulfanilic acid
• Errors in calculations
• The fact that the water samples were not always fresh samples
• Procedures were done over a period of different days
Conclusion
Heavy Metal Analysis
Lead, Mercury, and Silver
Performed by Ben
Health Hazards
• Mercury– From industrial and agricultural sources– .002 ppm EPA level– elemental mercury damages brain and kidneys– methylmercury- formed in water, most toxic
• bioaccumulative• very small levels cause severe neurological damage
and death• most severe in infants and children
Health Hazards
• Lead– from industrial and agricultural sources– .015 ppm EPA level– delay mental and physical development in
infants and children– affects the heart liver, and nervous system and
causes kidney problems and high blood pressure in adults
Health hazards
• Silver– from industrial and agricultural sources– low toxicity to humans– no EPA level found
Gravimetric Analysis
• Metal ions precipitated out as insoluble chlorides with HCl
• Then the precipitates were separated• PbCl2
– dissolves in boiling water, others won’t– remaining precipitates filtered out– acetic acid and K2CrO4 added to filtrate to
obtain PbCrO4
Gravimetric Analysis continued
• Hg2CL2– Remaining precipitate added to 6 M NH4OH – AgCl dissolves– Hg2Cl2 reacts with NH4OH to form
HgNH2CL, a black to gray precipitate– filtered and dried
Gravimetric Analysis continued
• AgCl– 6 M HNO3 added to filtrate– A white AgCl precipitate forms in an acidic
environment– filtered and dried
Water Sample results
mercury lead silver
East branch above the dam
Below detectable limits
Below detectable limits
Below detectable limits
East branch below the dam
Below detectable limits
Below detectable limits
Below detectable limits
West branch above P.H.G.
Below detectable limits
Below detectable limits
Below detectable limits
West Branch below P.H.G.
Below detectable limits
Below detectable limits
Below detectable limits
South Branch Below detectable limits
Below detectable limits
Below detectable limits
Codorus Creek Indian Rock
Below detectable limits
Below detectable limits
Below detectable limits
Codorus Creek Philadelphia St
Below detectable limits
Below detectable limits
Below detectable limits
Detectable limits
• Using chloride forms of metals, the lowest concentration able to form precipitate was 50 ppm
• Also, the lowest detectable limit using the current balances is 1.7 ppm
Errors
• Gravimetric analysis may not be best method due to minute levels to be measured
• Also, measuring for elemental forms of the metal, which in water may be present in other forms, such as methylmercury or lead sulfides
Top Related