Environmental Engineering Reference
In-Depth Information
table .
examples of Manufacturing Methods for target nanomaterials
nanomaterial
Process description
Ref.
Titanium.dioxide
Minerals.rutile.(TiO
2
).and.ilmenite.(FeTiO
3
).are.extracted.from.heavy.
mineral.sands..Nanoscale.particles.can.be.manufactured.by.milling,.
but.iner.TiO
2
.particles.can.be.manufactured.by.a.combination.of.
chemical.synthesis.and.milling:.
[9-11]
.
.
Prepare.aqueous.solution.of.TiCl
4
.in.solution.with.HCl,.HPO
4
.
.
.
.Vacuum-dry.solution.and.spray-dry.at.200-250°C.to.produce.dry.
TiO
2
.
.
.
.Calcinate.at.600-900°C.for.0.5-8.hours.to.produce.crystalline.
nanostructure.
.
.
.Wash.precipitate.with.C
2
H
5
OH,.dry,.and.mill.to.nano-sized.
particles.
Zero-valent.iron
The.following.processes.are.currently.used.in.commercial.production.
to.manufacture.nano.zero-valent.iron:
[12-14]
.
.
.React.ferric.chloride.with.sodium.borohydride.to.create.particles.
approximately.50.nm.in.diameter.
.
.
.React.iron.oxides.(goethite.and.hematite).with.hydrogen.at.200-
600°C.to.form.particles.approximately.70.nm.in.diameter.
containing.Fe
0
.and.Fe
3
O
4
.
Silver
Silver.is.recovered.from.ore.via.smelting.and.electrolysis..Nanoscale.
particles.can.be.created.by.several.processes:
[15-17]
.
.
.Silver.powder.can.be.generated.by.atomizing.molten.silver.(e.g.,.
via.a.high-velocity.gas.jet).to.create.very.small.droplets.that.then.
solidify.into.powder.form.
.
.
.Very.ine.silver.particles.are.more.commonly.produced.by.
chemical.precipitation,.e.g.,.from.silver.nitrate.using.a.reducing.
agent.(e.g.,.ascorbic.acid)..In.a.new.variation.on.this.process,.the.
reaction.occurs.in.a.spinning.disk.processor.(SDP);.nanoparticles.
5-200.nm.form.in.a.thin.luid.ilm.on.the.rotating.disk.surface.
.
.
.Nanometer-sized.angular.silver.particles.(1-100.nm).are.produced.
when.a.high-power.laser.beam.strikes.a.metallic.block.of.silver.
immersed.in.a.silver.salt.solution.
.
.
.Electrolysis.of.a.silver.electrode.in.deionized.water.produces.
colloidal.silver.containing.both.metallic.silver.particles.(1-25.
wt%).and.silver.ions.(75-99.wt%).
