Go to any chemistry conference these days and you’ll find multiple sessions on green chemistry. They won’t be talking about making green paints or growing plants. Actually that isn’t true. They may be talking about these things but not the way you might think. They may talk about making green paints that don’t release VOCs, volatile organic compounds. They may talk about growing plants using pesticides that don’t derive from petroleum. “Green chemistry,” you see, is all about using renewable resources and designing products and processes that minimize the use of and generation of hazardous substances. It’s all about minimizing the impact of the chemical industry on the environment. And to stimulate innovation in this area the U.S. offers a slate of Presidential Green Chemistry Challenge Awards. This year one of these went to BioAmber Inc. for its production of biobased succinic acid! Admittedly this Award doesn’t quite have the aura of an Oscar, but for those in the know, it’s a biggy. Why? Because it is given for an innovation that is likely to make the world a better place. A greener place. Chances are that you have never heard of succinic acid, but in the chemical industry it is a prized commodity. It is used to make plastics, synthetic fibres, detergents, deicing agents and plasticizers. It is an approved flavouring agent for food and finds numerous applications in the pharmaceutical industry. Today most succinic acid is made by reacting maleic anhydride with hydrogen. But therein lies a problem. The usual starting materials for the synthesis of maleic anhydride, benzene or butane, both come from petroleum. That’s why any process that can produce succinic acid from a renewable resource qualifies as a move towards greener chemistry.
Microorganisms such as bacteria or yeasts are like little chemical factories. Lactobacillus bacteria can make yogurt for us, and enzymes in yeast can convert sugars into alcohol. Evidently there are also microbes that can convert plant materials into succinic acid. As one might expect, the exact nature of these microbes is a trade secret because biobased succinic acid is a potential gold mine. Just to give you an idea, the prime target for replacement with biobased succinic acid would be petroleum derived maleic anhydride, which now has a global market of some 1.65 million tons a year. Estimates are that succinic acid made from a renewable resource could bring in about $1.3 billion a year. BioAmber is not there yet. But it is running the world’s first biobased succinic acid plant in France and is building a larger scale plant in the U.S. Right now the feedstock is glucose derived from wheat, but the goal for the future is to use agricultural and forestry waste. Green feedstocks for green chemistry!
