To rein in global warming, scientists believe it will not be
enough to reduce our greenhouse gas emissions: we will also need to remove CO2
from the atmosphere.
Soils are an important reservoir for carbon, as they contain
nearly double that found in the atmosphere and vegetation combined.
Agricultural practices have degraded soil carbon stocks, so there is a large
potential for atmospheric carbon to be sequestered in soils.
Mangroves help fight climate change but they’re at serious risk from its effects. That’s one of the findings from a study of a massive mangrove dieback that occurred in late 2015.
Local fishermen reported mangroves were dying along hundreds of kilometres along the Gulf of Carpentaria coastline, an area known for its barramundi fishing and high value commercial fisheries.
This caught the attention of Dr Damien Maher of Southern Cross University, who is interested in the chemistry of mangroves—how they store carbon in their soils, remove planet-warming nitrous oxides from the atmosphere, and neutralise ocean acidification by releasing alkaline chemicals into nearby waters.
Imagine printing your own room lighting, lasers, or solar cells from inks you buy at the local newsagent. Jacek Jasieniak and colleagues at CSIRO, the University of Melbourne and the University of Padua in Italy, have developed liquid inks based on quantum dots that can be used to print such devices and in the first demonstration of their technology have produced tiny lasers. Quantum dots are made of semiconductor material grown as nanometre-sized crystals, around a millionth of a millimetre in diameter. The laser colour they produce can be selectively tuned by varying their size.
High tech cling wraps that ‘sieve out’ carbon dioxide from waste gases can help save the world, says Melbourne University chemical engineer, Colin Scholes who developed the technology. The membranes can be fitted to existing chimneys where they capture CO2 for removal and storage. Not only are the new membranes efficient, they are also relatively cheap to produce. They are already being tested on brown coal power stations in Victoria’s La Trobe Valley, Colin says. “We are hoping these membranes will cut emissions from power stations by up to 90 per cent.”
Making cement is the third largest source of carbon emissions in the world after the burning of fossil fuels and deforestation—but the Australian roads of the future could be paved with cement that is made in a process that generates less than half the carbon emissions of traditional methods.
Each year, the world produces about 12 billion tonnes of concrete and about 1.6 billion tonnes of its key ingredient, Portland cement, which is generated by breaking calcium carbonate into carbon dioxide and calcium oxide.
This produces some 2 billion tons of carbon dioxide—so the Geopolymer and Mineral Processing Group (GMPG) at the University of Melbourne, now led by Dr John Provis, went looking for a lower carbon way of making cement.
They have now developed binders and concretes based on a low-CO2 aluminosilicate compounds called geopolymers.
A sponge that filters hot air and captures carbon dioxide
We need better ways of capturing carbon dioxide emissions from power stations and industry. And we won’t be using hydrogen cars until we’ve developed practical ways of carrying enough hydrogen gas in the fuel tank. Deanna D’Alessandro’s understanding of basic chemistry has led her to create new, incredibly absorbent chemicals that could do both these jobs and much more.
It’s all to do with surface area. Working in California and in Sydney she has constructed crystals that are full of minute holes. One teaspoon of the most effective of her chemicals has the surface area of a rugby field. What’s more, the size and shape of the pores can be customised using light. So she believes she can create molecular sponges that will mop up carbon dioxide, hydrogen, or in theory almost any gas – and then release it on cue. Continue reading Mopping up gases→
Ocean acidification, caused by increasing amounts of atmospheric carbon dioxide dissolving in the ocean, poses a serious threat to marine ecosystems.
Increasing acidity affects the ability of some planktonic organisms to form shells, and is expected to change the species composition of plankton, with flow-on effects to higher levels of the food web.
The CRC Programme has contributed funding towards the most comprehensive pilot project in the world to commercially test the storage and monitoring of concentrated carbon dioxide deep underground in geological formations, undertaken by the CRC for Greenhouse Gas Technologies.