Link: https://renewable-carbon.eu/news/sustainable-electronics-compostable-circuit-boards-made-from-citric-acid-production-waste/

Instead of disposing of this biomass waste, the team processes it into a plastic-like material through an innovative process involving molding and air-drying, resulting in a small, approximately 0.5 cm thick plate with a density of 1.23 g/cm³, comparable to the density of conventional printed circuit boards (PCBs). Using direct ink writing or a standard etching process and manual soldering, the researchers were able to deposit electronic components directly onto the fungal plates.

That's neat. Do we also have compostable components? If so, we could have fully compostable devices. :D

If you can compost the board you can recover the components / metals more easily … maybe?

Are there use cases where it's especially important for circuit boards to be compostable?

They'd be good for anything disposable that will be thrown into the trash

I guess the used vapes I find lying around have circuit boards in them

Do we also have compostable components?

I know only a bit about bio-tech that comes from fungi, and people are working on it, but we're not there yet to my understanding. As one example, researchers from The Ohio State University recently discovered that common edible fungi, such as shiitake mushrooms, can be grown and trained to act as organic memristors, a type of data processor that can remember past electrical states.

This one looks like that:

And here are some relevant articles, in case you feel like checking them out.

Given how many are out there, anyone making a compostable RFID chip should get a prize.

I suppose it makes extracting the valuable/scarce materials easier when the circuit boards brick

Yeah, but we could also ban vapes without replaceable batteries that cannot be charged.

There's no reason for vapes to exist that are throwaway products.

Powerbanks can be charged. Vapes are just smaller powerbanks with a heating element.

The coil should be fairly easy. Just find something that's conductive and compostable.

The tiny silicone chip will be much harder to replace.

When the PCB is sus 📮

I don't know all the details, but the impression I get is that much of the popularity of disposable vapes has been driven by regulatory efforts to crack down on other aspects of vaping, even when the disposable vapes themselves are made illegal by them:

But Nancy Heredia-Villanueva, the mom who stormed the gas station, says local authorities in her area haven't shown interest in enforcing sales of illegal vapes – even though they're specifically banned in New Jersey law.

First, she reported the store to police: "I had to actually email ordinances to the detective," she says. "And even then, he was like: 'Well, what am I supposed to do about it?'

In general it seems like a complex issue with a variety of things behind it (at least one comment here implies that bans on taking vapes on planes also drives the use of disposables for instance), so if the goal is to address the e-waste part of the problem I could see how you might want a multi-pronged approach. But yeah compostable circuit boards isn't really a total solution, those things also have lithium batteries etc.