Bioremoval of methylene blue dye using chitosan stabilized Pickering emulsion liquid membrane: optimization by Box–Behnken response surface design

Abstract

Chitosan, an eco-friendly biopolymer, was employed as a novel emulsifier in the sequestration of methylene blue (MB) dye from aqueous solution using Pickering emulsion liquid membrane (PELM). In the present study the PELM consists of aliquat 336 as extractant, potassium hydroxide (KOH) as a stripping agent, and coconut oil as the green diluent. Response surface methodology derived from Box–Behnken design (BBD) was applied for optimizing the operational parameters affecting the MB extraction. The results obtained from BBD design showed the maximum extraction of 89.99% at chitosan concentration of 0.10 w/v %, KOH (Internal phase) concentration of 0.8 M, MB concentration of 7.5 ppm, O/A ratio of 1 and stirring speed of 400 rpm. Investigations proved that chitosan biopolymer an eco-friendly emulsifying agent can be successfully used in PELM preparation for the extraction of dye bearing wastewater.

Graphical Abstract

Keywords:

• Pickering emulsion liquid membrane
• chitosan
• methylene blue
• extraction
• Box–Behnken design