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  • Original Paper: Sol–gel and hybrid materials for energy, environment and building applications
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Eco-friendly and efficient demulsification by chitosan biopolymer modified with titanium dioxide nanohybrid on carbonaceous substrates in (W/O) emulsions of crude oil


Oil refinery activities have increased and the utilization of chemicals in the industry has enhanced and generated various types of wastewater. The main objective of this work was the optimization and enhancement of the efficiency of chitosan biopolymer for eco-friendly and efficient rapid demulsification. Environmental and economic viability of chitosan production are of utmost importance nowadays. Chitosan is widely regarded a non-toxic and biologically compatible polymer. In this work, chitosan and its composite with titanium dioxide nanoparticles modified by zirconium on carbonaceous compounds such as graphene oxide (GO) and carboxylic functionalized, multi-walled carbon nanotubes (MWCNT-COOH) have been prepared by the sol–gel method. Several spectroscopic techniques have been applied to characterize the structures and properties of the nanoparticles prepared. The demulsification efficiency of four biocomposites was investigated under different conditions of concentration, settling time, and temperature. The demulsification activity of chitosan with titanium dioxide nanohybrid on graphene oxide (CT/TZG) was optimized via response surface method combined with central composite design (CCD). The results revealed that the maximum demulsification efficiency of 100% was achieved under optimum conditions at temperature, concentration, and time of 65 °C, 100 ppm, and 100 min, respectively.

Graphical abstract


  • A novel chitosan biopolymer modified with nano titania and carbonaceous substrate was used to chemically demulsify water in crude oil emulsions (W/O).

  • According to the results, the demulsifiers show good performance in the demulsification of W/O emulsions.

  • RSM and CCD were used to optimize the demulsification efficiency.

  • Demulsifier concentration and temperature significantly affected the demulsification efficiency.

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Correspondence to Marzieh Shekarriz.

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Bigdeli, T., Shekarriz, M., Mehdizadeh, A. et al. Eco-friendly and efficient demulsification by chitosan biopolymer modified with titanium dioxide nanohybrid on carbonaceous substrates in (W/O) emulsions of crude oil. J Sol-Gel Sci Technol 104, 211–224 (2022).

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  • Chitosan
  • TiO2
  • Graphene oxide
  • Sol–gel
  • Demulsification