This study aims to separate the gold of handphone circuit board scraps (PCBs) using Na2S2O5 methods that are environmentally friendly. The paper reports a promosing method to gold separation of PCBs. The gold Separation consisted of three phases; the determination of the optimum conditions using the method of Na2S2O5 solution of the gold standard and the application of methods of Na2S2O5 in used electronic scraps. Characterization of gold was analyzed by XRF and AAS. Hydrothermal process was applied, aqua regia and HNO3 solutions were used in the leaching processes, then Na2S2O5 as a precipitant in the separation process. Silver, Copper, ferous, alumunium, lead were solved in HNO3 and, but gold still as a solid residue. Gold separation of solid residue by leaching with aqua regia. Gold formed as a brown solid with the amount precipitated 0.046g for 5g PCBs samples treated, also it found high purity 99.3%.
Malaysian government introduced Small Renewable Energy Power (SREP) Program in 2001. In this paper, it discussed the possibility to utilize ocean wave in Merang shore, Terengganu, Malaysia. Besides, this paper also discusses the current technologies have been used to convert wave energy to electricity. The work principle of the devices also present in this paper. After that, sea condition in Malaysia was explored to study the possibility of utilization of wave energy in Malaysia. Finally, It is found Merang shore is the idea location to utilize the wave energy in Malaysia. Mean wave height and mean wave period at the location are 0.95 meter and 3.5 second. Also, attenuator type wave converter developed by Wave Star was considered as one of the possible devices to install at the location. From the calculation, the research obtained that the total rate of electrical power possible to grid is 649 MWh a year if only one set of C5 Wave star device install at Merang shore, Terengganu.
Department of Aeronautic, Automotive and Ocean Engineering, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, Malaysia
