In the present study, DEHP in selected municipal sewage (raw and treated) and industrial sludges of Taiwan was quantified by SFE and GC/EID. As a precursor, the optimal operating parameters of SFE were identified by laboratory experiments using DEHP spiked quartz sand. DEHP extraction efficiency was increased by the addition of modifier i.e. methanol (0.5mL, 7%). DEHP concentration in all sewage sludge (M-1 to M-4) and a textile industry (I-6) samples were above the limit suggested by the European Union (100mg/kg). The results suggest that excess DEHP concentration observed in the sewage sludge needs considerable attention before disposal.
- Di-(2-ethylhexyl) phthalate
- Sewage sludge
- Soil fertilizer
- Supercritical fluid extraction