Interfaces selectivas para recuperar Ag(I) de lixiviados de e-waste: evaluación de eficiencia basada en DEA

The efficiency of selective separation interfaces (SSIs) for recovering Ag(I) from e-waste leachates was examined through Data Envelopment Analysis (DEA) as a multicriteria assessment framework. The SSIs were produced by a dissolution–casting–evaporation route using cellulose triacetate as the polymeric support, dissolved in dichloromethane, and tris(2-ethylhexyl) phosphate (TEHP) as the carrier-phase component. Transport tests were conducted in a two-compartment diffusion cell under controlled conditions (V_d = 80 mL, V_a = 80 mL, A = 4.9 cm², 500 rpm, and 180 min). Ag(I) was quantified by UV–Vis spectrophotometry at 404 nm using an external calibration curve (Abs = 0.0052·C_{Ag(I)} + 0.0149; r = 0.9998; C in ppm), with matrix blanks used for background correction. An output-oriented BCC DEA model was applied to 18 experimental configurations (DMUs), considering SSI thickness (δ), carrier concentration (C_{car}) and energy consumption (E) as inputs, and extraction (%), flux (J) and selectivity (S) as outputs. The assessment identified 9 DMUs on the efficient frontier (score = 1.000), whereas the inefficient cases required output expansions of up to Φ = 1.328 (≈32.8%) to match the best observed performance. Overall, the results provide a quantitative basis for ranking SSI designs according to silver recovery performance and resource use.