Extraction behavior and selective separation of lead(II) using N,N-dioctyldiglycol amic acid.

Area of Science:

• Environmental Chemistry
• Separation Science
• Hydrometallurgy

Background:

• Divalent metal ion contamination in aqueous solutions poses environmental and health risks.
• Efficient separation of lead (Pb2+) from other heavy metals is crucial for remediation and resource recovery.
• Conventional extractants often lack the selectivity and efficiency required for complex mixtures.

Purpose of the Study:

• To investigate the selective separation of lead ions (Pb2+) from a mixture of divalent metal ions using liquid-liquid extraction.
• To evaluate the performance of N,N-Dioctyldiglycol amic acid (DODGAA) as a novel extractant for lead.
• To understand the mechanism and conditions for efficient lead extraction and stripping.

Main Methods:

• Liquid-liquid extraction was employed to separate Pb2+ from aqueous solutions containing Cu2+, Cd2+, Zn2+, Mn2+, Co2+, and Ni2+.
• N,N-Dioctyldiglycol amic acid (DODGAA) was used as the selective extractant.
• Extraction efficiency, selectivity, and stripping were analyzed under mildly acidic conditions.

Main Results:

• DODGAA enabled quantitative extraction and efficient separation of Pb2+ from the multi-metal ion mixture.
• DODGAA demonstrated superior extraction performance and selectivity for Pb2+ compared to conventional extractants.
• The extraction mechanism involves a proton-exchange reaction, forming a 1:2 Pb(DODGAA)2 complex.
• Pb2+ was readily stripped from the organic phase, allowing for the recycling of DODGAA.

Conclusions:

• N,N-Dioctyldiglycol amic acid (DODGAA) is a highly effective and selective extractant for separating lead ions from complex aqueous mixtures.
• The developed liquid-liquid extraction method using DODGAA offers a promising approach for lead remediation and recovery.
• The recyclability of DODGAA enhances the economic and environmental viability of the separation process.