Poly(lactic acid)/poly(butylene succinate) dual-layer membranes with cellulose nanowhisker for heavy metal ion separation

Int J Biol Macromol. 2021 Dec 1:192:654-664. doi: 10.1016/j.ijbiomac.2021.10.042. Epub 2021 Oct 13.

Abstract

In this study, poly(lactic acid) (PLA)/poly(butylene succinate) (PBS) dual-layer membranes filled with 0-3 wt% cellulose nanowhisker (CNWs) were fabricated with aim to remove metal ions from wastewater. An integrated method was employed in the membrane fabrication process by combining water vapor-induced and crystallization-induced phase inversions. The membrane thickness was measured in between 11 and 13 μm, which did not pose significant flux deviation during filtration process. The 3% CNW filled membrane showed prominent and well-laminated two layers structure. Meanwhile, the increase in CNWs from 0 to 3% loadings could improve the membrane porosity (43-74%) but reducing pore size (2.45-0.54 μm). The heat resistance of neat membrane enhanced by 1% CNW but decreased with loadings of 2-3% CNWs due to flaming behavior of sulphated nanocellulose. Membrane with 3% CNW displayed the tensile strength (23.5 MPa), elongation at break (7.1%), and Young's modulus (0.75 GPa) as compared to other samples. For wastewater filtration performance, the continuous operation test showed that 3% CNW filled membrane exhibited the highest removal efficiency for both cobalt and nickel metal ions reaching to 83% and 84%, respectively. We concluded that CNWs filled dual-layer membranes have potential for future development in the removal of heavy metal ions from wastewater streams.

Keywords: Cellulose nanowhisker; Dual-layer membranes; Poly(butylene succinate); Poly(lactic acid).

MeSH terms

  • Adsorption
  • Butylene Glycols / chemistry*
  • Cellulose / chemistry*
  • Chemical Phenomena
  • Ions / chemistry*
  • Mechanical Phenomena
  • Membranes, Artificial*
  • Metals, Heavy / chemistry*
  • Nanocomposites / chemistry*
  • Nanocomposites / ultrastructure
  • Polyesters / chemistry*
  • Polymers / chemistry*
  • Porosity
  • Spectrum Analysis
  • Thermogravimetry

Substances

  • Butylene Glycols
  • Ions
  • Membranes, Artificial
  • Metals, Heavy
  • Polyesters
  • Polymers
  • bionole
  • poly(lactide)
  • Cellulose