Initial Study of Nickel Electrolyte for EnFACE Process

Nickel electrolyte for a micro-pattern transfer process without photolithography, EnFACE, has been developed. Previous work on copper deposition indicated that a conductivity of ~2.7 Sm-1 is required. Electrochemical parameters of electrolyte i.e. current density and overpotential are also crucial to govern a successful pattern replication. Therefore, the investigation focused on the measurement of physicochemical properties and electrochemical behaviour of the electrolyte at different nickel concentrations and complexing agents of chloride and sulfamate. Nickel electrolytes containing sulfamate, chloride and combined sulfamate-chloride with concentrations between 0.14 M and 0.3 M were investigated. Physicochemical properties i.e. pH and conductivity were measured to ensure if they were in the desired value. The electrochemical behaviour of the electrolytes was measured by polarisation experiments in a standard three-electrode cell. The working electrode was a copper disc (surface area of 0.196 cm2) and the counter electrode was platinum mesh. The potential was measured againts a saturated calomel reference electrode (SCE). The experiments were carried out at various scan rate and Rotating Disc Electrode (RDE) rotation speed to see the effect of scan rate and agitation. Based on the measured physicochemical properties, the electrolyte of 0.19 M nickel sulfamate was chosen for experimentation. Polarisation curve of agitated solution suggested that overall nickel electrodeposition reaction is controlled by a combination of kinetics and mass transfer. Reduction potential of nickel was in the range of -0.7 to -1.0 V. The corresponding current densities for nickel deposition were in the range of -0.1 to -1.5 mA cm-2

Prarancangan Pabrik Asam Sulfat dari Sulfur dan Udara Kapasitas 325.000 ton/tahun

Sulfuric acid plant raw material with sulfur and air capacity of 325,000 tons/year it is planned to operate for 330 days/year. Products of sulfuric acid (98%) produced as much as 41,035.3535 kg/hour of need as much sulfur raw materials 13,218.9274 kg\/h and air dry as much as 84,905.6490 kg/h. Supporting utilities water supply include process amounted to 767,024.80 kg\/h, the electric needs of 650.157 kW obtained from the State electricity company (PLN) and supplied generator set as a backup. The planned factory is established in Banyuwangi, East Java by 2020 with a land area of 10,492 m2 and require employees of 282 people. Using sulfuric acid factory fixed capital is Rp. 700,551,445,143.45 and working capital amounting to Rp. 135,930,726,589. Economic analysis of the results against the factory obtained results Percent Return on Investment before tax amounting to 32.8% and after tax of 26.3%. Pay Out Time before tax amounted to 2.34 years and after of 2.76 years. Break Even Point (BEP) of 44,62%, Shut Down Point (SDP) by 21% and the Discounted Cash Flow (DCF) for 39,28 percent. From the above data then it can be inferred that the factory is profitable and viable. Keywords : sulphuric acid, kontak process, fixed be