Environmental Engineering Reference
In-Depth Information
FiguRe .
Plot.of.apparent.solubility.coeficient.(
k
as
).against.particle.size.and.density.
than.that.of.lead,.(11.5.g/cm
3
),.all.particles.within.the.deinition.of.a.nanomaterial.
will.possess.high.
k
as
.values.and.capacity.for.metastable.suspension.(Figure.6.3)..This.
method.can.be.applied.to.materials.containing.particles.in.a.range.of.sizes.by.dein-
ing.the.volume.as.a.distribution.function.(f(
V
x
))..Figure.6.4.provides.an.example.of.
this.type.of.application.to.an.aqueous.suspension.of.nanoparticle-sized.zero-valent.
iron.(nZVI).
As.noted.above,.the.derivation.of.this.method.assumed.that.the.nanomaterials.
are.inert.and.do.not.interact.with.environmental.constituents..If.not,.then.the.integra-
tion.of.the.Boltzmann.model.represents.only.the.initial.situation..To.determine.the.
stability.of.nanoparticle.suspensions.in.reactive.environments,.dynamic.time-course.
chemical.reactions.must.be.taken.into.account.to.predict.the.nanomaterial's.sol.sta-
bility.and.thereby.its.potential.for.transport.and.receptor.exposure.
6.2.2 C
hemiCal
F
OrCes
a
Cting
On
n
anOmaterials
If. nanoparticle. size. changes. as. the. result. of. interactions. within. the. environment,.
then.the.kinetics.of.the.suspension.will.change..For.example,.agglomeration.result-
ing.from.the.chemical.interactions.of.the.nanoparticles.with.like.particles.or.with.
certain. environmental. constituents. may. increase. the. effective. particle. size.. When.
this.increase.in.size.reduces.the.particles'.buoyancy.suficiently,.they.no.longer.stay.
