Tuesday, April 29, 2008

Gasoline from Plastic Wastes: How Soon?

As the security of our global food supply became increasingly threatened by climate change, not to mention our current hastily set-up and ill-conceived bio-fuel industry. Add to that the urgent need to clean up our environment, will fuels from plastic wastes solve this and our present pollution dilemma?


By: Vanessa Uy


Though the concept’s feasibility has been around since plastics were industrially manufactured from crude oil, converting our hydrocarbon-based plastic wastes into hydrocarbon-based fuels like gasoline and diesel never really catch-on for quite a while. The reason for this is mostly – if not the only reason - due to our heavily politicized way of running our current industry and economy. Let’s take a brief history lesson.

Before the establishment of OPEC in 1973, the West has been purchasing oil – mostly from the Gulf States – at one US dollar per barrel. A price that was mandated by the US government since that fateful day back in March 3, 1938, when crude oil was discovered in Saudi Arabia by an American oil company – Standard Oil. The intervening years after the establishment of OPEC, the reason for not scaling up to industrial scale the chemistry lab curiosity of converting disused plastics into gasoline is political – has become a favorite of conspiracy theorists. Do they offend the Oil / Petroleum Lobbyists? Not to mention the gasoline price rollback in the US back in 1995 finally destined disuse plastics sourced gasoline a mere lab curiosity. But is procrastinating the industrial application of this procedure really good for our environment’s long-term future, given our present skyrocketing crude oil prices? Not to mention our ever pressing need to protect our planet and feed our poor and hungry brethren which our present ill-conceived bio-fuel industry had created more problems than it intends to solve?

The latest incarnation of this process is the pet project of General Motors chemist Dr. Candice Wheeler. Called De-Polymerization Thermal Conversion Process, it converts crude oil sourced hydrocarbon polymers which makes up most of our existing plastics back into monomers i.e. hydrocarbon-based fuels. Since these plastics are created by the polymerization of crude oil sourced petrochemicals, logically, this chemical process can also be reversed to turn into hydrocarbon monomers which is very similar chemical structure – make that indistinguishable from - of the hydrocarbon fuels like gasoline and diesel now in current use. Though this latest version of De-Polymerization has the advantage of requiring less heat compared to the ones performed in the past. Which is good for two reasons, number one is less energy means savings in financial terms, number two is less energy means less greenhouse gas generated by the process – which is what is aimed for in the first place.

Though the plastic wastes must be sorted out first according to chemical structure since different kinds of plastics has a slightly different chemical structure. And more importantly, chlorine and other halide containing plastics like polyvinyl chloride or PVC should be processed separately because these plastics released toxic gases similar to that used in chemical warfare like phosgene.

Like hydrocarbon based bio-fuels, gasoline and / or diesel that’s derived from our plastic waste is a very attractive proposition and it’s not just about reducing our volume of solid waste that we generate. Gasoline and diesel that’s made from plastic wastes can mesh seamlessly with the industrial and economic incumbency (i.e. gasoline and diesel powered vehicles were here first, unjust starvation and global warming – though a product of our societal and political follies - came in later) with the existing technology already in use. Motor vehicle manufacturers are less likely to spend billions just to make their vehicles run on some newfangled environmentally friendly fuel whose supposed manufacturer can’t produce enough to meet demand. So that is the reason why gasoline and diesel compatible food crop derived bio-fuels are being widely mass-produced in a hurry because existing cars can run on them.

But there is a food crisis right now that demands a quick solution. To ease the demand on food, and of our conscience, we should derive our hydrocarbon fuels from sources other than food crops which the rest of our brethren needs. By deriving our fuels from a source that’s not being needed as food and also a source that if left unused threatens our planet. Then it’s the closest to a magic bullet solution to our problems yet.

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