Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Physicochemical Problems of Mineral Processing

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: laterite ore

Sortuj według:

Ogranicz wyniki do:

Effects and mechanism of Bayer red mud on co-reduction with a saprolitic laterite ore to prepare ferronickel

Wang Xiaoping, Sun Tichang, Wu Shichao, Hu Tianyang, Rong Lingkun

Physicochemical Problems of Mineral Processing

2020

Vol. 56, iss. 4

641--652

Co-reduction of a saprolitic laterite and waste Bayer red mud was investigated to prepare ferronickel powder. The synchronous reduction and comprehensive recovery of nickel and iron in the low-grade laterite ores and iron in the red mud were realized. At the red mud dosage of 50 wt%, ferronickel powder with nickel and iron grades of 5.58 wt% and 89.91 wt% was obtained. The corresponding nickel and total iron recoveries were 93.11 wt% and 90.23 wt%, respectively. The red mud enhanced the nickel recovery of the saprolitic laterite ore evidently, attributing to the formation of low-melting anorthite, omphacite, and diopside during co-reduction. This led that NiO in the saprolitic ore was released. Meanwhile, obvious melting phenomenon of the roasting system was appeared, enhancing the growth of the ferronickel particles.

Atmospheric pressure leaching of nickel from a low-grade nickel-bearing ore

Javanshir S., Mofrad Z. H., Azargoon A.

Physicochemical Problems of Mineral Processing

2018

Vol. 54, iss. 3

890--900

This study focused on the extraction of nickel from a low-grade lateritic ore. The characterization of representative samples was done by X-ray diffraction (XRD), X-ray fluorescence (XRF), and microscopic mineralogical studies. Nickel was uniformly distributed in iron (hydr)oxide minerals. The pre-concentration of nickel was attempted by magnetic separation, but was unsuccessful. The effect of the type of lixiviant, acid concentration, S/L ratio, time, and temperature were investigated in the atmospheric leaching process. Based on the experimental data, optimum conditions for the maximum recovery of nickel were determined under the following conditions: 5 M H2SO4, 25% (w/v), 90 ºC, and two hours. Pre-calcination, for increasing nickel extraction by converting goethite to hematite, was carried out on raw ores at different times (30-180 minutes) and temperatures (180-540 ºC). Recovery was found increasing from 69 to 95% under the same conditions. Kinetic studies were conducted by fitting the data with Shrinking Core (SC) models. The study determined, from the estimate of activation energy, that the rate of reaction controlled by chemical reaction.