Water treatment by polysulfone membrane modified with tetrahydrofuran and water pressure

We report an effective method for separating sodium alginate through polysulfone (PSf) membranes modified with tetrahydrofuran (THF) and water pressure. The PSf supports were dipped into THF and then exposed to water pressure. Upon the application of water pressure, the PSf supports showed interconnected “sponge-like” pores structures and had a higher porosity of 24.6% than did the neat PSf support. In addition, the modified PSf support at 8 bar for 30 s showed the highest water flux of 259 L/m²h in the sodium alginate filtration test. Furthermore, the modified PSf support at 8 bar for 1 min showed a notable sodium alginate rejection of 98.8%. These results were attributable to the weakened interactions of the polysulfone chain when the PSf supports were exposed to THF and water pressure of 8 bar. The higher porosity of the modified supports was confirmed by scanning electron microscopy (SEM) and porosimeter data. [Figure not available: see fulltext.]