Our current focus is the innovative use of nanomaterials and nanotechnology to add new properties to New Zealand's natural raw materials to create novel high-value products for international markets.
We work at the interface of materials chemistry and industry. Our current focus is the innovative use of nanomaterials and nanotechnology to add new properties to New Zealand's natural raw materials to create novel high–value products for international markets. We are also committed to the development and use of new sustainable manufacturing processes. Professor Jim Johnston leads this active research group. He is also a Principal Investigator in the MacDiarmid Institute for Advance Materials and Nanotechnology.
Our long-term goal is to establish new export manufacturing industries in New Zealand and to provide new products and technologies to local and international industries.
Our innovative research utilises a broad range of locally–produced raw materials that include merino wool, cellulose fibres from wood, silica–rich geothermal waste–water, organic materials in waste streams from agriculture and wood pulp. We add substantial value to these raw materials through the use of nanomaterials, functionalisation and new process technologies.
We work extensively with both New Zealand and international companies. Our long–term goal is to establish new export manufacturing industries in New Zealand and to provide new products and technologies to local and international industries.
The development and commercialisation of all our technologies and associated products is an important part of our strategy. This is consistent with the government’s desire to support existing local industries and establish new knowledge-based industries with high added value to support the growth of New Zealand's high-tech sector.
We are actively involved in establishing new export manufacturing businesses and licensing and partnering with New Zealand and international companies with complementary interests. Students in the group gain valuable insights working with these companies on the process of commercialisation of new products and technologies.
Gold wool and silver wool
Prof Jim Johnston and Dr Kerstin Lucas have successfully led the development of our gold wool product. They have utilised nanotechnology to incorporate nanogold as a colourfast colourant in New Zealand merino and strong wool fibres.
Nano–Structured Calcium Silicate
We have developed a suite of designer nano–structured calcium silicate materials with micron size particles comprising a 3D arrangement of stacked nanosize platelets. The material has a high pore volume for liquid absorption and a highly accessible surface area that can be functionalised to bind different chemical species. Applications being pursued include its use in filled and coated paper to improve print quality, anti–corrosive and anti–microbial paints, the recovery of phosphate and heavy metals from waste streams, and in composite phase change materials for passive heat storage and release. No other products currently in the marketplace have this unique combination of properties. The material can be produced from sodium silicate or geothermal water.
The technology has now been fully developed on a laboratory scale and implemented at a pilot scale operation in the US. We are negotiating with interested parties regarding sale or licence agreements.
Enhanced Energy Recovery from Geothermal Waters
The unwanted deposition of amorphous silica from the separated geothermal water, supersaturated in dissolved silica following the steam/water separation process, is a major problem worldwide and results in blocked pipes, heat exchangers and re–injection wells. It necessitates the use of higher steam/water separation temperatures, higher binary cycle heat exchanger temperatures and lower overall heat recovery.
We have carried out research to control the precipitation of dissolved silica and produce a nano–structured calcium silicate product, which does not adhere to the surface of pipes or heat exchangers and can be readily separated as a useful product prior to reinjection. This enables the use of higher steam–water separation temperatures for steam production as well as greater heat recovery from the separated water in the heat exchangers of a binary cycle electricity generating plant. Both of these factors enable more electricity to be generated from the geothermal resource.
The technology has the potential to increase the recovery of geothermal heat energy for electricity production by about 10–15%. In addition, maintenance and field operating costs will be considerably reduced.
The laboratory scale development is now complete and investment is being sought to implement the technology at pilot scale prior to commercialisation.
Wet Air Oxidation
We have developed a proprietary wet air oxidation technology to degrade problematic organic components of waste water streams from agricultural and food processing industries. This enables the safe disposal of the waste stream to surface waterways. Applications for this technology include dairy sheds and milk, vegetable and meat processing operations.
The unwanted organic material is oxidised in water at an elevated temperature and pressure. This process breaks it down into smaller molecules that can be readily digested by microbes and substantially reduces the chemical and biological oxygen demand of the waste stream. It can then be safely discharged to a waterway or used as a chemical feedstock, in the plastics industry for example.
Our technology will enable industries to meet the increasingly stringent environmental requirements and compliance costs that relate to the discharge of organic waste into surface waterways. Some current disposal practices are no longer acceptable or sustainable and this new technology offers a simple and attractive solution. It is applicable both in New Zealand and worldwide.
A new company Wetox Ltd was established in 2010 to commercialise the technology.