CIRCULAR REVOLUTION: FROM POISON TO ENERGETIC POSSIBILITY

The circular economy isn’t just about generating value from waste.

It’s also about making the best out of the worst – pollution.

And environmental pollution doesn’t come packaged worse than toxic heavy metals.

TOXIC HEAVY METALS

These substances are not only toxic.

They also cannot be destroyed or degraded.

They are in their simplest form and that’s the form in which they can do maximum damage.

So once they are unleashed on our environment, they circulate in the soil, water, air and also in the bodies of animals and humans perrenially.

But which activities release these substances to torment us this way?

Well, several human activities like battery recycling, metal processing, leather tanning, plastic manufacture, mining and even…get this…fertilizer manufacture could be formidable sources of toxic heavy metals around us.

Activities that generate products that we need on a daily basis.

So get this…we need these products.

However, the processes or raw materials used to produce them unleash toxic heavy metals upon us…

And mind you, these same toxic metals cannot be destroyed in any way.

So if exposed to them, we take them in through food, water or the air we breathe making us vulnerable to disease.

This looks like a lost cause.

But is it?

CIRCULAR ECONOMY

So if we can’t destroy these substances, how about we find use for them in applications that ‘lock’ them up from the environment for ages?

This is one goal of the circular economy and by extension, sustainability…

Drawing out benefits from what is risky around us.

If that’s the case, what can we conjure up with these poisons?

ENERGY

There seems to be a unique relationship between toxic heavy metals and energy.

Just picture the lead-acid battery.

An age-old piece of scientific art that delivers the needed energy to power our cars and homes.

All this capability arises from lead, a metal that has long been associated with mental health deterioration in kids.

Some environmental activists might rightfully express concern over safety of such batteries but what’s the recourse?

Even if all industries shut down, lead metal would continuously be produced through natural processes like fission of uranium.

It’ll still be around us.

So why not look for applications that prevent it from reentering the environment…

And lead-acid battery technology is one such application…but not the only one.

ELECTRONICS

The advent of the information age carries with it a craving for supercomputers.

These are computers that process information extremely fast allowing them to do more within a very short span of time.

Hey, let’s not forget AI, machine learning, blockchain and other emerging technologies changing our lives on a daily basis.

At the heart of all of these cutting edge technologies lies a device that was once large in size.

However, today, it could be 50 times smaller than the pinky fingernail – the transistor.

Transistors help process information while giving us feedback. They do this by amplifying electrical signals.

Picture your computer processor that gives you feedback once you key in a command.

Now these transistors are made of semiconductor materials which are somewhere between metals and insulators.

Silicon is the most well-known.

But there are still others which have the same if not a greater capability.

And believe me, some of these emerging semiconductor materials are composed of toxic heavy metals.

For example, cadmium based semiconductors have found good use in solar energy generation.

Lots of research has gone into the use of cadmium telluride, cadmium selenide, cadmium sulfide and cadmium arsenide in this regard.

Others might include gallium arsenide.

Also, gallium arsenide is very useful in manufacturing if circuit boards are used extensively in electronic devices.

It’s worth noting that cadmium and arsenic are well documented toxic metals with cancer-causing capabilities.

So why not ‘confine’ them in such electronic applications over the long-haul?

But not only are these toxic substances useful in transistors.

LIGHTING

Ever marveled at multicolored lighting we see in urban areas?

Well, some of these lights are produced by devices called light emitting diodes (LEDs).

These are semiconductor devices that separate charge and convert it into light when the charges combine.

The cool thing is that they use very minimal electricity.

Substances like lead sulfide and some compounds of cadmium like the ones mentioned above have this light generation capability.

LEDs have several advantages over conventional lighting systems.

First , as stated earlier , they use minimum electricity.

Second, their material composition could be engineered to produce varying colors.

Lastly – and relevant to our discussion – they could utilize the most toxic of substances (toxic metals) to produce light.

But the light at the end of the toxic tunnel just doesn’t stop here.

FLUORESCENT BULBS

Ever wondered how a long tube filled with gas seems to glow once you switch on the power?

Fluorescent bulbs are a marvel of lighting technology because they utilize the release of light by excited mercury vapor.

MERCURY

Mercury is as toxic as they come.

This metal destroys the nervous system, damages major organs and accumulates in the body over time irreversibly.

Worse still, it’s an element that can not be destroyed once it pervades our environment.

But beyond the toxic talk that mercury brings, there seems to be a silver lining.

Atoms of some substances undergo excitation of their electrons once they are energized – by electricity

But these excited electrons don’t remain so forever – they lose their excitation as they emit the trapped energy in the form of light.

Now, mercury is unique in a number of ways.

First, the light it’s atoms emit is visible – you can see it.

Secondly, it emits many colors of light at the same time.

So when these emissions combine, they form white light.

Lastly, mercury vapor could be used for over 10,000 hours like a fluorescent lamp, making it an attractive way of storing this toxic metal away from our environment as it delivers value light to us.

But beyond this light, another application seems to shine when it comes to one of the most notorious metallic pollutant around us.

CHROMIUM

Chromium doesn’t seem to have any direct electrical or electronic application.

However, it could utilize electric power in order to be stored safely.

Chromium pollution comes from activities like leather tanning and metal smelting.

Exposure to it – especially through air pollution – carries a risk of development of lung cancer.

So leather tanning workers are endangered in this regard.

However, hidden within this risky trait is it’s ability to resist corrosion or rusting.

Metals like iron are degraded by water leading to rust formation.

However, if a coating of chromium is applied on the surface of iron, this rusting is drastically reduced.

But we can’t start chipping pieces of poisonous chromium to stick them onto iron.

No way. Instead, we use an electrically driven process called electrolysis to do that.

Electrolysis helps in development of rust resistant steels for construction of buildings, bridges, and automobiles – imagine those alloy rims – and even in making industrial tools.

IN CONCLUSION

There’s always something good that can come out of even the worst of us.

This is not only confined to humanity but is possible in all of God’s creation.

Elements are the simplest forms for God’s creation, and so we can find good use for them no matter how risky they appear to be.

Toxic heavy metals are no exception.

Originally posted on Cleannovate Blog