Improved Performance of Polysulfone Ultrafiltration Membrane Using TCPP by Post-Modification Method

Abstract

Ultrafiltration (UF) membranes have found great application in sewage purification and desalination due to their high permeation flux and high rejection rate for contaminants under low-pressure conditions, but the flux and antifouling ability of UF membranes needs to be improved. Tetrakis (4-carboxyphenyl) porphyrin (TCPP) has good hydrophilicity, and it is protonated under strongly acidic conditions and then forms strong hydrogen bonds with N, O and S, so that the TCPP would be well anchored in the membrane. In this work, NaHCO 3 was used to dissolve TCPP and TMC (trimesoyl chloride) was used to produce a strong acid. Then, TCPP was modified in a membrane with a different rejection rate by a method similar to interfacial polymerization. Performance tests of TCPP/polysulfone (PSf) membranes show that for the membrane with a high BSA (bovine serum albumin) rejection, when the ratio of NaHCO 3 to TCPP is 16:1 (wt.%), the pure water flux of membrane Z1 16:1 is increased by 34% (from 455 to 614 Lm −2 h −1 bar −1 ) while the membrane retention was maintained above 95%. As for the membrane with a low BSA rejection, when the ratio of NaHCO 3 to TCPP was 32:1, the rejection of membrane B2 32:1 was found to increase from 81% to 96%. Although the flux of membrane B2 32:1 decreased, it remained at 638 Lm −2 h −1 bar −1 , which is comparable to the reported polymer ultrafiltration membrane. The above dual results are thought to be attributed to the synergistic effect of protonated TCPP and NaHCO 3 , where the former increases membrane flux and the latter increases the membrane rejection rate. This work provides a way for the application of porphyrin and porphyrin framework materials in membrane separation.

TCPP/MgO-loaded PLGA microspheres combining photodynamic antibacterial therapy with PBM-assisted fibroblast activation to treat periodontitis

“…31 PMT exhibited a characteristic absorption sharp peak of TCPP (C-N, at 963 cm −1 ). 32 In short, the FTIR spectrum demonstrated the successful synthesis of various microspheres. The content of TCPP in PMT was also determined.…”

Rapid Surface Modification of Ultrafiltration Membranes for Enhanced Antifouling Properties

“…There are many studies which have reported the low antifouling properties of these UF membranes during the filtration process. For instance, Jia et al [8] found the severe flux decline (>80% flux reduction) of the PSf-based membrane after being tested for 1000 mg/L bovine serum albumin (BSA) solution for 5 h. Jamshidi Gohari et al [9] reported that the flat sheet membrane made of PES suffered from great irreversible fouling resistance (R ir : 0.46) compared to the nanomaterials-modified PES membrane (R ir : 0.04) after both membranes were tested under the same conditions using 1000 mg/L BSA solution for 2 h. Rahimi et al [10] on the other hand reported that PVDF membrane was very susceptible to the organic foulants present in the solution. The statement was supported by the remarkable flux deterioration (>66% flux reduction) and the formation of a cake layer on the membrane surface.…”