Binchotan carbon to filter tap water, from dream to reality

Do you purify your tap water with Binchotan charcoal, or the Chinese version made from bamboo charcoal, sold under a number of brand names? Before you hear the cries from the back of the room, here is one of my sources of information, and there are many others, which testify not so much to the danger of binchotan coal as to its uselessness: "Activated carbon: does putting binchotan in water make sense? by www.lexpress.fr.

WHAT IS BINCHOTAN?

For those who don't use it, we owe them a brief explanation of the exact nature of this particular charcoal.

Activated carbon

Binchotan carbon is a type of activated carbon. Now, you might ask, "What the hell is activated carbon?

Well, activated carbon is made from organic materials such as wood, coconut shells or sugar residues. It is made by burning these materials at high temperatures, which creates microscopic pores in the charcoal. These pores allow the activated carbon to capture certain impurities in the water. or air (a phenomenon called "adsorption", which is different from "absorption").

Activated carbon is often used in the following applications cartridges of your filter jugs for example, in order to purifying tap water (But is it effective? See our article on carafe filter).

Binchotan, a Japanese activated carbon

Le white charcoal binchotan is a type of Japanese activated carbon made from the Japanese ubamegashi holm oak. This oak grows mainly in a region formerly known as the province of Kishu and more specifically in the town of Wakayama (other towns and regions in Japan produce it today).

It is made using a low-temperature combustion process in which wood is burnt in an earthen furnace for several days. This creates very dense and hard charcoal sticks with a relatively smaller specific surface area than conventional activated carbons, but with a higher adsorption capacity.

Some people therefore consider Binchotans to be effective for water and air purification because of their ability to adsorb impurities and odours.

Le Binchotan coal from Kishu is considered to be of the highest quality, thanks to the quality of the wood used and the know-how and experience of local producers.

Now you know (just about!) everything you need to know to continue our discussion.

Read also: Tap water filter: What to choose

DO YOU THINK BINCHOTAN IS ORGANIC?

I'd like to say yes, just as much as destroying the Amazon rainforests by fire!

Unfortunately, this is oak wood burnt at very high temperatures (from 400 to 1200°C) for dozens of hours (up to 15 days!). This process releases fumesand fine particles and CO2. The final product will then be transported 10,000 km from its place of production, while being wrapped in aluminised plastic for preservation.

It will then redo a few thousand km by lorry to reach the depot or shop before you get home to filter your tap water: it's anything but sustainable.

The only thing organic about it (apart from the fact that you can find it in organic shops...) is that it's easier to recycle than a carafe filter. It decomposes very easily in the soil. So for the environment : binchotan coal danger !

Oh yes, it's prettier too.

DO YOU THINK BINCHOTAN ACTIVATED CARBON IS EFFECTIVE?

Perhaps a little. There is indeed a change in flavour, but strangely enough, no independent scientific study has proven the real benefits of its use. Did you say bizarre?

What effect does this purification method really have on the heavy metals, pesticides, traces of fertiliser and drug residues contained in tap water?

We will have to make do with manufacturers' claims alone. Curious for a food product, which should be controlled before being put on the market...

Read also: Tap water filter: Which one to choose?

DO YOU THINK THAT BOILING THE BINCHOTAN IS ENOUGH TO REGENERATE IT?

No way! This sterilisesbut does not regenerate its adsorption capacity. The pores would have to be unblocked in an oven at 1200°C to make it "activated" again.

You are therefore advised to change it regularly, but nobody knows how often. We also don't know how long it will take to purify a certain volume of water.

On the other hand, boiling it once a week is not recommended by some, means a much higher carbon footprint. The choice is yours.

DO YOU THINK BINCHOTAN COAL IS CHEAP?

Real Binchotan from Japan (for a 1l jug) costs around €40 a year, or €200 every 5 years. That's certainly cheaper than plastic bottles of mineral water, but it's far from free.

Fake binchotan coal, of uncertain provenance and available almost everywhere, is a little cheaper. However, it may be chemically activated with products that aren't very cool, or that are badly burnt and contain residual tar or some other unpleasant surprise... It is therefore in its counterfeiting lies the danger of binchotan coal.

Read also: The most common water filtration methods: advantages and disadvantages

BUT HOW MUCH WATER CAN I PRODUCE EVERY DAY?

Some sources say that the water is perfect after 4 hours. But what do they really know, without measuring?

That's one litre in the morning, one litre in the afternoon and possibly a litre more if you remember to fill the jug in the evening. These quantities are not sufficient for a family.Unless you have two decanters. So much wasted space and handling.

Conclusion: look around you, there are absolute solutions, scientifically verified and no more expensive, with a real guarantee of bacterial non-proliferation: https://lavie.bio

Pascal Nuti - CIO Solable - Passionate about energy, I'm constantly on the lookout for new targets for improvement, exploring cross-disciplinary paths using novel methods.

Article written on 30/05/2023 published updated on 26/07/2024