Separation of Ni(II) from Nickel-Containing Wastewater in an Emulsion Liquid Membrane System with P507 as Carrier
An effective emulsion liquid membrane system with P507 as carrier, Span-80 as surfactant and H2SO4 as internal aqueous phase was established to treat Ni(Ⅱ)-containing wastewater. The effects of volume fraction of Span-80 in the oil phase(φ(Span-80)), emulsifying stirring speed(ν1), separation stirring speed(ν2), volume fraction of P507(φ(P507)), volume ratio of oil phase to internal phase(Roi), milk phase to water phase(Rew) and concentration of H2SO4 in internal aqueous phase on Ni(Ⅱ) migrating rate have been investigated in the course of migrating of nickel ions in the system. The optimal operation conditions were determined to be: φ(Span-80)=8.5%,ν1 =3600 r·min-1,ν2 =320 r·min-1, φ(P507)=6.5%, Roi =1:1, Rew =2:5 and c(H2SO4)=1.6 mol·L-1 ,under which the migrating rate of nickel ions reached above 97%.