Easy removing of phenol from wastewater using vegetable oil-based organic solvent in emulsion liquid membrane process

•Environmental friendly emulsion liquid membrane process for phenol removal from wastewater•Green palm oil based organic solvent•83% phenol was removed in the process.•Enrichment ratio of phenol in the recovery phase was 11 times.

Phenol is considered as pollutant due to its toxicity and carcinogenic effect. Thus, variety of innovative methods for separation and recovery of phenolic compounds is developed in order to remove the unwanted phenol from wastewater and obtain valuable phenolic compound. One of potential method is extraction using green based liquid organic solvent. Therefore, the feasibility of using palm oil was investigated. In this research, palm oil based organic phase was used as diluents to treat a simulated wastewater containing 300 × 10-6 of phenol solution using emulsion liquid membrane process (ELM). The stability of water-in-oil (W/O) emulsion on diluent composition and the parameters affecting the phenol removal efficiency and stability of the emulsion; such as emulsification speed, emulsification time, agitation speed, surfactant concentration, pH of external phase, contact time, stripping agent concentration and treat ratio were carried out. The results of ELM study showed that at ratio 7 to 3 of palm oil to kerosene, 5 min and 1300 r·min− 1 of emulsification process the stabile primary emulsion were formed. Also, no carrier is needed to facilitate the phenol extraction. In experimental conditions of 500 r·min− 1 of agitation speed, 3% Span 80, pH 8 of external phase, 5 min of contact time, 0.1 mol·L− 1 NaOH as stripping agent and 1:10 of treat ratio, the ELM process was very promising for removing the phenol from the wastewater. The extraction performance at about 83% of phenol was removed for simulated wastewater and an enrichment of phenol in recovery phase as phenolate compound was around 11 times.