TY - JOUR
T1 - Characterisation and hydrometallurgical processing of nickel from tropical agromined bio-ore
AU - Vaughan, James
AU - Riggio, Justin
AU - Chen, Jeff
AU - Peng, Hong
AU - Harris, Hugh H.
AU - van der Ent, Antony
PY - 2017/5/1
Y1 - 2017/5/1
N2 - Hyperaccumulator plants (“metal crops”) can be used for selective extraction of Ni from low-grade resources, thereby producing a high-grade “bio-ore”. This so-called agromining (or phytomining) technology involves farming select metal crops on ultramafic soils, mineral wastes, or overburden that are sub-economic Ni resources for conventional extractive technology. Key to profiting from agromining is the efficient recovery of Ni and by-products from the bio-ore, either directly from freshly harvested biomass or from the ash after incineration. Bio-ore of wild grown specimens of the Ni hyperaccumulator plants Rinorea bengalensis and Phyllanthus securinegoides were collected in Malaysia. After incineration, the ash composites contained 5.5 and 12.7 wt% Ni for Rinorea and Phyllanthus respectively, along with substantial amounts of Ca, K, C, Mg, P, Na, S and Cl. Other minor impurities included Si, Fe, Al, Mn and Zn. The solids were characterised in detail by SEM-EDS, XRD and XANES. The effect of solution chemistry on the leaching behaviour of the bio-ore (dried biomass and ash) was also assessed. A hydrometallurgical process for recovering Ni from the bio-ore was then demonstrated. The processes involves the bio-ore (ash) being water-washed, yielding > 90% recovery of K to solution. After water washing, > 95% Ni recovery was achieved by H2SO4 leaching at 60 °C, although long residence times and high acid concentrations were required. Ni(OH)2 was then precipitated from solution using the K2CO3 rich wash-water. The bio-ore generated precipitant was compared with NaOH and MgO used industrially.
AB - Hyperaccumulator plants (“metal crops”) can be used for selective extraction of Ni from low-grade resources, thereby producing a high-grade “bio-ore”. This so-called agromining (or phytomining) technology involves farming select metal crops on ultramafic soils, mineral wastes, or overburden that are sub-economic Ni resources for conventional extractive technology. Key to profiting from agromining is the efficient recovery of Ni and by-products from the bio-ore, either directly from freshly harvested biomass or from the ash after incineration. Bio-ore of wild grown specimens of the Ni hyperaccumulator plants Rinorea bengalensis and Phyllanthus securinegoides were collected in Malaysia. After incineration, the ash composites contained 5.5 and 12.7 wt% Ni for Rinorea and Phyllanthus respectively, along with substantial amounts of Ca, K, C, Mg, P, Na, S and Cl. Other minor impurities included Si, Fe, Al, Mn and Zn. The solids were characterised in detail by SEM-EDS, XRD and XANES. The effect of solution chemistry on the leaching behaviour of the bio-ore (dried biomass and ash) was also assessed. A hydrometallurgical process for recovering Ni from the bio-ore was then demonstrated. The processes involves the bio-ore (ash) being water-washed, yielding > 90% recovery of K to solution. After water washing, > 95% Ni recovery was achieved by H2SO4 leaching at 60 °C, although long residence times and high acid concentrations were required. Ni(OH)2 was then precipitated from solution using the K2CO3 rich wash-water. The bio-ore generated precipitant was compared with NaOH and MgO used industrially.
KW - Agromining
KW - Bio-ore
KW - Nickel
KW - Phytomining
KW - Tropical hyperaccumulator
U2 - 10.1016/j.hydromet.2017.01.012
DO - 10.1016/j.hydromet.2017.01.012
M3 - Article
AN - SCOPUS:85014193976
SN - 0304-386X
VL - 169
SP - 346
EP - 355
JO - Hydrometallurgy
JF - Hydrometallurgy
ER -