Single stream recycling: How do they sort this mess out?. Lots of ingenuity…and knowledge of physical and chemical properties!. Separation of Mixtures. Mixtures may be separated by many different techniques based on differing physical and/or chemical properties. S eparation challenges.
Single stream recycling:
How do they sort this mess out?
Lots of ingenuity…and knowledge of physical and chemical properties!
Separation of Mixtures
Mixtures may be separated by many different techniques based on differing physical and/or chemical properties
Simply picking apart the different components:
Use screens to sort by size:
or gold nuggets
Particles separated form liquid or gas:
Lab filter setup with funnel
Pouring liquid off of settled mixture:
Wine from sediment
Water in water treatment plant
Iron from aluminum, plastic, and paper
at recycling plant
Different types of plastic at recycling plant
Oil on water
If one substance dissolves and another doesn’t
Salt and sand…salt dissolves in water…sand doesn’t…sand settles
Tea flavor from tea leaves
Spinning to pull heavier part of mixture to bottom
Blood cells are separated
The spin cycle in the washer removes water from clothes
Differences in boiling points can be used to separate liquids
(differences in freezing and sublimation points may also be used )
Alcohol in stills
“chroma” meaning color,
technique was first used for dyes
A moving phase carries sample along over or through a stationary phase.
Components are separated because they have different attractions for the phases so some move faster than others.
Paper chromatography to separate ink pigments
Many variations for many different mixtures
Remove a liquid from
Sea salt isolated by evaporating sea water in shallow ponds
Solids may also be purified by recrystallization
Motion… a dog shaking to remove water
Gravity/density… gentle shaking causes dense items to sink and less dense to rise
Almost any difference in physical properties can be used to separate mixtures physically Differences in chemical properties can also be used to separate mixtures chemically. For example, oil floats on water (physical difference in density) and burns, but water does not (chemical property of flammability)
are limited only by people’s (or wizard’s ingenuity!)