Post on 24-Dec-2015
Analysis of Total Aluminum and Dissolved Aluminum
Louis McDonald and Jeff SkousenPlant & Soil Sciences
West Virginia University
Al3+ Complexes
Aluminum Complexes
Inorganic
e.g. fluoride, hydroxide, sulfate, carbonate
Organic
Al3+ O5
Al3+ Complexes
Aluminum Complexes
Inorganic Organic
Small Largee.g. acetic, citric e.g. humic acid,
fulvic acid
hydroxide
7
Aluminum ParticlesBy Composition
Aluminum hydroxides and oxides Gibbsite (Al(OH)3)
Aluminosilicates
Phyllosilicates Kaolinite (Si2Al5(OH)4)
Feldspar (KAlSi3O8)
Kaolinite Al2Si2O5(OH)4
9
Aluminum ParticlesBy Size
LargeMediumSmallV. Small
SandsSiltsClaysVery fine clays
Colloids – Al on surface does matter10
Al3+ Complexes
Inorganic Organic
Small Large
Particles
V. Small
Small
Medium
Large
Very Small Very Large
OH-
12
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
OH-
13
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
OH-
14
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
OH-
PolynuclearAl
18
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved 20
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
Why filter? PROPERLY!
21
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
What do instruments measure?
22
Acidifying Samples
+ Acid, H+
Al3+
Al – ComplexesAl in SolidsAl on Surfaces
Al3+
H – ComplexesAl in SolidsH on Surfaces
Dissolved Al DissolvedAl
23
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
Why might hardness matter?
24
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
What is toxic?
25
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
What is toxic?
Ingestion orInhalation
26
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
What is toxic?
Plants, algae
27
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
What is toxic?
Fish acute
28
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
What is toxic?
Fish chronic?
29
Al3+ Complexes
Inorganic Organic
Small Large
Particles
Definitely Dissolved Definitely Solid
V. Small
Small
Medium
Large
Very Small Very Large
Filter SizeOperationally Dissolved
What is Total Al? What is dissolved Al?
30