3
Phase 2—SX Compatibility
Following promising results in the pre- screening tests,
ACORGA ® EW98 was evaluated for solvent extraction
compatibility which included strip kinetics, phase disen-
gagement and interfacial tension testing.
Strip kinetics were tested using ACORGA ® M5910 in
Orfom SX-12 diluent which was max loaded and filtered.
The lean electrolyte was 30 g/L Cu and 150 g/L acid and
included a dosage of 40 ppm ACORGA ® EW98, which
was chosen as an overdose condition for the compatibility
studies. A blank was also tested to provide a baseline and
resulting kinetics shown in Figure 4.
The results showed no significant impact to strip kinet-
ics and a 95% approach to equilibrium was achieved prior
to 30 seconds of mixing time.
Strip phase disengagement was tested using the same
electrolyte and organic make-up as previously stated.
ACORGA ® EW98 was again dosed into the electrolyte
at 40 ppm and phase disengagement times are shown in
Figure 5.
The addition of ACORGA EW98 showed no impact
to phase disengagement over 4 contacts. Phase disengage-
ment times remained consistent over the 4 contacts at ~
20 seconds. Lastly, interfacial tension (IFT) was measured
to evaluate the overall health of the organic after contact
with ACORGA ® EW98. In the event a surfactant is pres-
ent and transferred to the organic phase, a decrease in IFT
is observed.. A lower IFT (suggesting lower organic qual-
ity) can impact the physical performance of the SX circuit,
such as, increasing phase disengagement times and leading
to higher entrainment. Organic was contacted five times
with synthetic electrolyte dosed with 40 ppm ACORGA
EW98 (fresh electrolyte used for each contact). The result-
ing IFT measurements are shown in Figure 6.
A similar IFT value is seen after the five contacts sug-
gesting no accumulation in the organic phase. The IFT
testing along with the phase disengagement results support
that the additive remains in the aqueous phase and does not
transfer or accumulate in the organic. In addition to these
performance tests, the organic was analyzed for the mist
Figure 2. Pre-screening results for ACORGA® EW98
Figure 3. Acid mist suppression vs. concentration -
ACORGA® EW98
Figure 4. SX strip kinetics with 40 ppm dosage of
ACORGA® EW98
Figure 5. Strip phase disengagement with 40 ppm dosage of
ACORGA® EW98
Phase 2—SX Compatibility
Following promising results in the pre- screening tests,
ACORGA ® EW98 was evaluated for solvent extraction
compatibility which included strip kinetics, phase disen-
gagement and interfacial tension testing.
Strip kinetics were tested using ACORGA ® M5910 in
Orfom SX-12 diluent which was max loaded and filtered.
The lean electrolyte was 30 g/L Cu and 150 g/L acid and
included a dosage of 40 ppm ACORGA ® EW98, which
was chosen as an overdose condition for the compatibility
studies. A blank was also tested to provide a baseline and
resulting kinetics shown in Figure 4.
The results showed no significant impact to strip kinet-
ics and a 95% approach to equilibrium was achieved prior
to 30 seconds of mixing time.
Strip phase disengagement was tested using the same
electrolyte and organic make-up as previously stated.
ACORGA ® EW98 was again dosed into the electrolyte
at 40 ppm and phase disengagement times are shown in
Figure 5.
The addition of ACORGA EW98 showed no impact
to phase disengagement over 4 contacts. Phase disengage-
ment times remained consistent over the 4 contacts at ~
20 seconds. Lastly, interfacial tension (IFT) was measured
to evaluate the overall health of the organic after contact
with ACORGA ® EW98. In the event a surfactant is pres-
ent and transferred to the organic phase, a decrease in IFT
is observed.. A lower IFT (suggesting lower organic qual-
ity) can impact the physical performance of the SX circuit,
such as, increasing phase disengagement times and leading
to higher entrainment. Organic was contacted five times
with synthetic electrolyte dosed with 40 ppm ACORGA
EW98 (fresh electrolyte used for each contact). The result-
ing IFT measurements are shown in Figure 6.
A similar IFT value is seen after the five contacts sug-
gesting no accumulation in the organic phase. The IFT
testing along with the phase disengagement results support
that the additive remains in the aqueous phase and does not
transfer or accumulate in the organic. In addition to these
performance tests, the organic was analyzed for the mist
Figure 2. Pre-screening results for ACORGA® EW98
Figure 3. Acid mist suppression vs. concentration -
ACORGA® EW98
Figure 4. SX strip kinetics with 40 ppm dosage of
ACORGA® EW98
Figure 5. Strip phase disengagement with 40 ppm dosage of
ACORGA® EW98