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"Liquid Wood" a Contender To Replace Plastic
Ostracus recommends a Christian Science Monitor piece on the 40-year quest to find a replacement for non-biodegradable plastic. One candidate, written off 20 years back but now developed to the point of practicality, is a formulation based on the lignin found in wood. And it turns out there is another strong environmental reason to put lignin to use in this way: burning it, which is its common fate today, releases the carbon dioxide that trees had sequestered. "Almost 40 years ago, American scientists took their first steps in a quest to break the world's dependence on plastics. But in those four decades, plastic products have become so cheap and durable that not even the forces of nature seem able to stop them. A soupy expanse of plastic waste — too tough for bacteria to break down — now covers an estimated 1 million square miles of the Pacific Ocean. ...[R]esearchers started hunting for a substitute for plastic's main ingredient, petroleum. They wanted something renewable, biodegradable, and abundant enough to be inexpensive."
We *can* create oil, even out of plain CO2 if necessary. We do have the chemical knowledge for that you know.
Making any plastic will be still as easy as it is today : you buy some type of oil-derivative at the store, and polymerisize it. Easy enough.
It will however, be a very costly thing to do indeed : it requires loads of energy. Right now that energy has simply been put in oil long ago, and making most plastics is in fact an exotherm process.
We will still make plastics. Producing them, however, will stop producing energy and start massively costing energy.
So that leaves multiple scenarios open. If we do get fusion operational somehow, for example, plastics will likely be as abundant as they are today, at least for a while. Even if we don't nuclear power is probably cheap enough to provide all those "specialty plastics", maybe even at comparable prices. The mass-market plastic will be the only thing disappearing.
My guess is, we'd replace it by another extremely useful and versatile substance we so massively used before the oil started to get so widespread : Iron. It's only marginally more expensive than plastics (mostly due to the mines' labour cost, there is more than enough iron in the ground to coat the entire earth with it several times). Instead of buying your salami in cheap plastic packaging you'll simply buy it in a can.
My reading of this vaguely written sentence is that lignin is currently being burned. If instead used as a petroleum replacement in plastic-like materials it would not be burned -- at least not until it hits the post consumer trash incinerator.
Is lignin extracted from wood in any other industries besides paper production? Would the paper industry be able to supply enough lignin to replace even a fraction of the plastic currently being produced? Even if it did, sounds like that would simply shift the burning from lignin in the wood fiber to petroleum products.
At the paper mill where I recently worked, the lignin was not burned just for the pleasure of it. The quicky skipping a couple dozen steps process is as follows... The lignin is extracted from the wood pulp by a cocktaail of sodium family chemicals casually referred to as liquor. When loaded with nice potential energy filled lignin, the liquor is referred to as black liquor. The black liquor is piped to the recovery boilers where the lignin burns out leaving nice clean white liquor and a lot of high pressure steam. The white liquor is in closed loop system and goes back to pick up more lignin. The high pressure steam is used on the actual paper machines and drives turbines to provide nearly one hundred percent of the electrical power needed by the entire mill.
Remove the lignin by another process so that it can be used to make 'liquid wood'. Now where will the mill get its high pressure steam? Burning petroleum products just like it does now when there is an upset condition in the supply of black liquor. Lots of natural gas. Lots.
Although lingin-based plastics may be something new, bioplastics are by no means new.
By pure and honest coincidence, I have a disposable cup made out of a plant-based bioplastic sitting on my desk that I got from a restaurant along with some take-out earlier today.
It's virtually indistinguishable from a normal plastic cup, and actually looks a bit nicer than your typical disposable drinkware -- the crystal-clear bioplastic is sturdy and has a nice 'shine' to it. It's biodegradable, and contains no oil-based inputs, although you'd never guess it by looking at it or handling it.
The manufacturers of the biopolymer claim that it can be adapted to all sorts of other products, at what seem to be fairly reasonable prices (~$1/kg). What's not to love?
-- If you try to fail and succeed, which have you done? - Uli's moose