The effect of pre-treatments to the nickel limonite leaching using dissolved gaseous SO2-air

• Published in: IOP conference series. Materials Science and Engineering Vol. 285; no. 1
• Main Authors: Wulandari, W, Soerawidjaja, T H, Alifiani, D, Rangga, D A
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.01.2018
• Subjects: Iron; Leaching; Limonite; Nickel ores; Pretreatment; Recovery; Roasting; Selectivity; Sodium carbonate
• ISSN: 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/285/1/012006

Nickel limonite leaching has been subjected to a number of studies, one of the method is by using dissolved gaseous SO2-air. The selectivity of nickel over iron extracted from leaching using dissolved gaseous SO2-air is advantageous, however the nickel that can be recovered is limited. This paper studies pre-treatments that is applied to the nickel ore prior leaching in order to increase the recovery of dissolved nickel from nickel limonite ore. There two pre-treatments that were carried out in this research, roasting and alkali-roasting using Na2CO3. The extraction was carried out for 180 min with pH 2, 3, 4, and 5 and temperature 30, 55, and 80 °C. It is found that the highest yield is achieved at pH 2 and 80 °C with nickel recovery of 61.39%. At pH 2, for alkali-roasting pre-treatment, the nickel yield raised from 28.17% to 100% and for roasting pre-treatment the nickel yield increased from 20.42% to 61.39%. However, at pH 2, the nickel to iron selectivity decreased from 96272 to 534 for roasting pre-treatment and from 1.8 to 1 for alkali-roasting pre-treatment.