Aerogel: Heavy Metal Ions
Week #12: Current & Future Consequences
Preface ✨
Hello everyone!
My intentions for writing these articles are:
- Explain technical information about aerogels in simple terms (to the public)
- Store information and habits for my future self and others (in <7 minutes)
Coolio? Sweet. Enjoy the series :-)
TL;DR Heavy Metal Ions 💠
“In a genuine way, then, materials are a reflection of who we are, a multi-scale expression of our human needs and desires.” — Mark Miodownik
Humans have developed new materials since the beginning of civilization to advance society. Some were made by accident, some with intentions, but the outcome remained the same:
They impacted society’s desire for advancement, order, & progress.
Not every method of development is efficient for the future. Some of these methods include:
- Agriculture Runoff (e.g. fertilizers)
- Mining
- Industrial Manufacturing (e.g. spilling of toxic chemicals, waste)
The accelerated pace of industrialization has led to the release of heavy metal ions entering our potable drinking water.
765 million people drink a certain amount of heavy metal ions in their drinking water every day. About 2.1 billion people today lack access to safe drinking water.
How Mining Creates Heavy Metal Ions 🚱
Mining is done for many reasons & intentions. One of the objectives is to find precious minerals like gold, silver, copper, etc.
Most of these precious minerals are found in ores. Ores are solid materials (like rocks) containing precious metals/minerals.
The process of extracting precious metals from ore is called “extractive metallurgy”, and the overall process is as follows:
- Separate the ore from unwanted rocks.
- The minerals (gold, silver, etc.) are separated from the ore.
- Separation methods progress because most minerals are not pure metals.
Large pieces of the ore feed are broken through crushing and/or grinding. This process extracts leftover waste from the ore extraction that is released into the environment and contaminates our water sources.
The process below is known as “Hydrometallurgy”:
(Leaching) → Metal ions are extracted from their ore by water/acids/bases solutions.
Leaching breaks down the material structure of the ore and allows for other reactions to occur to the precious metals. The common reaction is for these “free metals” to give up their outermost electrons (outer shell)
Most heavy metal ions lose two of their electrons. This causes the heavy metal ions to be very reactive and cause damage inside human organs if consumed.
Let’s use copper as an example. Copper has 29 electrons. It has one electron in its outer (last) shell from the 29 protons in the nucleus.
The goal for any atom is to get rid of extra electrons that do not fill the entire valence shell. Copper’s 4th shell needs 32 electrons to be full. The outer shell only has one.
An atom is positively charged when it loses electrons (cations). The copper ion has a Cu+ charge when it lost its outermost electron.
But the common copper heavy metal ion loses two electrons from the atom. It loses the outermost electron and an extra electron from the third shell (counting from the nucleus.)
Losing an electron from a full electron shell requires an immense amount of energy. This energy comes from the extraction metallurgy process used to extract the minerals from the ore.
The heavy metal ion configuration (Cu2+) occurs in other valuable heavy metal ions like lead (Pb2+), cadmium (Cd2+), nickel (Ni2+), etc.
Heavy metal ions are soluble in water because their positive charge attracts the oxygen atom of the water molecule and allows for the transportation of the heavy metal throughout a water source and the human body.
The most dangerous reaction of heavy metal ions occurs in the body: heavy metal ions can bond to sulfhydryl groups which are found in proteins (muscles in the body) and enzymes. These metals bind to the enzymes preventing them from working properly, and stopping or altering their metabolic process.
Here is a list of the permitted intake of heavy metal ions before they cause damage to your organs/systems recommended by W.H.O. (mg/L):
Nickel - 0.02 mg/L
Copper - 2 mg/L
Zinc - 3 mg/L
Lead - 0.01 mg/L
Cadmium - 0.003 mg/L
Chromium - 0.05 mg/L
Maybe one of you is thinking if we can boil heavy metals out of water. You cannot do that. Here’s why:
The boiling point of water is 100°C (212°F). But the boiling point of lead is 1,749 °C (3,180 °F)
The water will boil first before the heavy metal ions. Good luck with that. 😐
Closing Thoughts & Final Outcomes 🔧
These processes have led to 400 million tons of heavy metal ions & sludge entering the world’s waters annually and 765 million people drinking this water every day. The common outcomes of drinking this water are:
- Death
- Cancer
- Birth Defects
It affects the >1 billion people who own land that make crops; the food that you will eat at the dinner table tonight. If their water’s dirty, your food is dirty. You could die.
Half the world’s population will lack access to clean water by 2030 if we fail to take action to prevent future consequences. You, your children, and your children’s children could perish because of dirty water: a resource that is essential to human survival.
“If we don’t study the mistakes of the future, we’re bound to repeat them for the first time.” — Ken M.
Solve the future’s problems. ✊
© 2023 by Carlos Manuel Jarquín Sánchez. All Rights Reserved.
