Zn–Ni sulfide selective precipitation: The role of supersaturation

Pollution control and metal resource recovery for acid mine drainage

“…As shown in Table 6, the REM Zn was also significantly aligned with the MOR, when the MOR was less than 2.0 and the R was 0.86. Secondly, the Cu concentration was only 5% of that in the Sampaio et al (2010) test, and it is harder for the supersaturation of the precipitate. Supersaturation, achieved by adding more sulphide, could speed up the precipitation process (Veeken et al, 2003).…”

“…As shown in Table 6, The REM Cu was only 36.08% when the MOR Cu was 1, and a MOR Cu of 2 was found to be the optimal value for Cu selective precipitation. However, Sampaio et al (2010) found that with a MOR of 1.1, the REM Cu was approximately 99%. The higher MOR Cu might be due to three reasons.…”

“…Flotation technology is frequently used for mineral enrichment, and the CuS and ZnS sludges could be refined further by this method (Avila et al, 2011;Pagnanelli et al, 2004;Pestryak et al, 2013). Sampaio et al (2010) found that with sulphide precipitation, the Cu sludge was covellite, while the Zn was spharelite. The median particle diameters of the Cu and Zn sludges were 7.5 μm and 5.24 μm, respectively.…”

“…Precipitators commonly used include sodium hydroxide, sodium sulphide and sodium decanoate (Jameson et al, 2010;Mauchauffée et al, 2008;Michalkova et al, 2007;Tokuda et al, 2008). Sampaio et al (2010) studied the sludge generated in the Zn selective precipitation process, and found that, with the addition of sodium sulphide, sphalerite could be detected in the sludge. This method reduced the overall volume of sludge by 70% compared to the chemical precipitation treatment with no metal recovery process (Silva et al, 2012).…”

Metal recovery from the copper sulfide tailing with leaching and fractional precipitation technology

“…With the UV conversion of the Fe sludge, magnetite particles could be obtained and it can be applied for the paint industry (Silva et al, 2012), while the Fe 2 O 3 content of the magnetite particles should be higher than 75%. It has been found that mostly Cu and Zn sludges and those generated in the sulfide precipitation process were covellite and spharelite (Sampaio et al, 2010), and those could be refined and sold to smelters to recover the metals (Cibati et al, 2013). Generally, the Cu and Zn contents of the sludge are about 0.5% and 2% for their flotation refinement respectively.…”