17 Jul 2014

Green Chemistry

From Our Changing World, 9:34 pm on 17 July 2014

Ex-pat Kiwi chemist Professor Terry Collins has been involved in the field of green chemistry since the early 1980s, and he’s hopeful that tiny catalysts that he’s designed will be a big help in removing chemicals, hormones and hormone-mimics from wastewater.

‘Green chemistry is really about designing chemical products and processes that reduce and eliminate hazardous substances. Basically, to get rid of toxic substances from the commercial space.’

Green chemistryTerry, who is the Teresa Heinz Professor of Green Chemistry at Carnegie Mellon University in the United States told Alison Ballance that the aim of his research was ‘to produce small molecules that would do what big enzymes do because small molecules are much easier to commercialise so that you could disinfect water with hydrogen peroxide rather than chlorine, to avoid chlorination disinfection by-products.’

Terry’s research, which began in the early 1980s, has developed ‘TAML Activators’, a new class of oxidation catalysts, which activate hydrogen peroxide to destroy chemicals in water.

Humans alive today have thousands more chemical compounds in their urine than their grandparents did. In a recent study Canadian researchers detected at least 3,079 compounds in urine. While 72 of these compounds are made by bacteria, and 1,453 come from the body itself, a further 2,282 come from diet, drugs, cosmetics or environmental exposure. Some of these anthropogenic chemicals are ingested deliberately, such as pharmaceuticals, while others, such as plasticisers, are by-products from common household items such as plastic bottles.

Of particular concern to Terry are endocrine disruptors, which affect human hormones and can have feminising or masculinising effects on humans and wildlife.

‘A very tiny amount of the catalyst in the water with hydrogen peroxide will break these endocrine disrupting compounds down very quickly’, says Terry ‘and it looks like it will be much more cost-effective and less energy intensive.’

Terry says the critical question for him was whether his catalysts might, in their turn become a problem, and so the catalysts have been subjected to – and passed – a number of tests to ensure they aren’t themselves endocrine disruptors.