TY - JOUR
T1 - Enhanced dissolution of tantalite/columbite following milling
AU - Welham, N. J.
PY - 2001
Y1 - 2001
N2 - A tantalum/niobium concentrate has been ball-milled for up to 50 h in a laboratory mill without apparent phase change, other than a decrease in unit cell symmetry and some amorphisation. The extent of dissolution in a mixture of hydrochloric acid and sodium fluoride increased with milling time. For a powder milled for 50 h, over 95% of the concentrate were solubilised in 24 h compared with ∼ 50% in 48 h for a 2-h milled powder. The kinetics of dissolution changed with the milling time, indicating a change in the rate-determining step due to milling. These effects were attributed to the decrease in crystallinity of the powder, giving a substantial increase in the lattice strain and in unsatisfied surface bonds where dissolution was thought to occur.
AB - A tantalum/niobium concentrate has been ball-milled for up to 50 h in a laboratory mill without apparent phase change, other than a decrease in unit cell symmetry and some amorphisation. The extent of dissolution in a mixture of hydrochloric acid and sodium fluoride increased with milling time. For a powder milled for 50 h, over 95% of the concentrate were solubilised in 24 h compared with ∼ 50% in 48 h for a 2-h milled powder. The kinetics of dissolution changed with the milling time, indicating a change in the rate-determining step due to milling. These effects were attributed to the decrease in crystallinity of the powder, giving a substantial increase in the lattice strain and in unsatisfied surface bonds where dissolution was thought to occur.
KW - Dissolution
KW - Mechanical activation
KW - Milling
UR - http://www.scopus.com/inward/record.url?scp=0035090149&partnerID=8YFLogxK
U2 - 10.1016/S0301-7516(00)00032-6
DO - 10.1016/S0301-7516(00)00032-6
M3 - Article
SN - 0301-7516
VL - 61
SP - 145
EP - 154
JO - International Journal of Mineral Processing
JF - International Journal of Mineral Processing
IS - 3
ER -