Recovery of Nickel from Selectively Reduced Laterite Ore by Sulphuric Acid Leaching.

Abstract

The laterite ore with low nickel content deposits in Indonesia can be expected to be an alternative raw material of iron making due to its high iron content. One of the required processes is the separation of nickel and cobalt from the laterite ore by leaching it with H 2 SO 4 at the atmospheric condition. The sample containing 50.88 % iron, 0.03 % cobalt and 0.30 % nickel was selectively reduced with CO/CO 2 mixed gas to obtain metallic nickel and cobalt, as well as magnetite from hematite. Accordingly, in the leaching process metallic nickel and cobalt will be dissolved by controlling the iron dissolving. The effects of various parameters have been examined. These condition include leaching time, temperature (303-343 K), H 2 SO 4 concentration (0.005-1.0) mol/l, as well as extraction rate of nickel.The result of the analysis indicated that the influence of selective reduction could speed up the nickel extraction and obstructed the iron dissolution. The extraction rate of nickel was very high for small particle and slower for larger size. The optimal condition of the test was obtained at the leaching temperature of 343 K, 0.05 mol/l H 2 SO 4 with a sample lower than 4.0 g/l. In 60 min after the test, about 93 mass% of nickel was extracted from the sample smaller than 44 mm. The nickel extraction would be higher by adding the leaching time. The rate of extraction was chemically controlled and the apparent activation energy was 42.2 kJ/mol. At the end of the leaching process, there was residual solid rich-magnetite and minimal nickel.

Microwave assisted atmospheric acid leaching of nickel from laterite ore

“…The apparent activation energy of the reaction was calculated to be 38.9 kJ/mol. The estimated apparent activation energy is in agreement with the previous study on the recovery of nickel from selectively reduced laterite ore by sulphuric acid leaching where an activation energy of 42.2 kJ/mol was reported [24]. …”

The Melting Reaction Mechanism of NaOH in Decomposing Ca2SiO4

“…Usually, the calcium, magnesium, and iron in the silicate is substituted with isomorphism elements of nickel, the main silicate forms in the ore could be as follows: Ni 2 SiO 3 Á mCa 2 SiO 4 Á nH 2 O, Ni 2 SiO 3 Á mMg 2 SiO 4 Á nH 2 O, Mg 3 Si 4 O 10 Á (OH) 2 , and Mg 2 Fe 0.2 SiO 4 (Kar et al 2000;. The Nickel element cannot be efficiently enriched from the silicate-type nickel laterite ore containing a relatively high content of calcium and magnesium silicate through a traditional method, which brings about great difficulty to use the type nickel laterite ore (Mcdonald and Whittington 2008;Moskalyk and Alfantazi 2002;Purwanto et al 2003;Stamboliadis et al 2004). Compared with the traditional beneficiation process, alkali processing of nickel laterite ore attracts wide concern, recently, due to its simple process, low energy consumption, and small investment (Zhao and Zhai 2013).…”

Extraction of Nickel from Morowali Laterite Ore with Nitric Acid

“…Mubarok & Fathoni (2016) and Astuti et al (2016) explained that theoretically, the higher the temperature, the more nickel will be obtained. In an experiment conducted by Purwanto (2003) and Wanta et al (2018), it was also stated that the concentration of the solution used in the leaching process could affect the product produced.…”