HKU Bulletin June 2006 (Vol. 7 No. 3)

15 Running on Green Power A new hybrid car joins the the University fleet. T he University has become the first tertiary institution in Hong Kong to purchase a hybrid car for its vehicle fleet, which will save on petrol and be kinder to the environment. The 1,500cc Toyota Prius, which operates on both batteries and petrol, consumes 50 per cent less petrol than a conventional petrol engine and emits 50 per cent fewer polluting emissions. It is also quieter. The Prius cost $70,000 more than a conventional Toyota 1,500cc, but Paul So, Senior Assistant Director of Estates, said the purchase had symbolic importance. “The University wants everyone to know that we need to protect the environment and we thought we should set an example here,” he said. “Hopefully when other departments need to replace a vehicle, they will buy one like this.” 14 SUSTAINABILITY Gold Extraction that Helps the Environment Scientists work with industry to extract gold. A collaborative project between University scientists and industry has resulted in a process that improves the removal of gold and silver from industrial wastewater, and helps the environment. The process is at least 10 times more effective than current technologies and leaves the water clean enough to be discharged into sewers. Scientists in the Department of Chemistry have developed the process in collaboration with Kenlap P.C.G. Manufacturer Co. Ltd., a subsidiary of Ocean Grand Chemicals Holdings, under the University-Industry Collaboration Programme. The company is contributing $900,000 and the government is providing matching funds through the Innovation and Technology Fund. Kenlap produces electroplating salts, such as gold and silver, for manufacturers on the Mainland. But clients said the residual materials in their wastewater meant it was too polluted for discharge. Kenlap then approached the University for help in addressing this problem. The process developed by the Department of Chemistry involves adding a polymer to the water, which traps the metal and can then be separated from the water. The results have come only a few months into the 18-month project, which began last November. The process will next be reproduced on a large-scale and metal residues will be extracted from the polymer, so they can be re-used. This is called reverse extraction. Professor Chan Kwong Yu, a Reader in the Department and leader of the project, said they would avoid burning the polymer, as in current reverse extraction methods, providing a further environmental benefit. They also expected the polymer, which was developed by Assistant Professor Dr Patrick Toy, could be re-used. “We feel strongly that we can do this once we extract a sufficient amount of gold from the wastewater,” he said. “At the end we expect to have an industrial-scale process and some intellectual property.”