Cellulose Based Cryogels as Adsorbents for Organic Pollutants

Author(s)

Toledo, Paulo V. O. ; Martins, Bianca F. ; Pirich, Cleverton L. ; Sierakowski, Maria Rita ; Teixeira Neto, Erico ; Petri, Denise F. S.

• Document type: Journal article
• Source: MACROMOLECULAR SYMPOSIA; v. 383, n. 1, p. 12-pg., 2019-02-01.

Abstract

Cryogels of hydroxypropyl methylcellulose (HPMC) and bacterial cellulose nanocrystals (CNC) were prepared with 0, 5, or 15 wt% contents of CNC. Two types of CNC were used, namely, CNC-SO4 and CNC, with zeta-potential values of - (46 +/- 1) mV and - (5 +/- 1) mV, respectively. Regardless the CNC type or content, all cryogels presented similar density, capillarity constant, contact angle, swelling rate values, and morphology. However, the addition of only 5% of CNC-SO4 to HPMC cryogels increased the compressive modulus from (120 +/- 15) kPa to (150 +/- 19) kPa. The cryogels were tested as adsorbents for 17 alpha-ethinyl estradiol (EE) and methylene blue (MB). In the dilute range, the pollutants removal efficiency of reinforced cryogels was considerably larger than that of neat cryogels. In the more concentrated range, all adsorbents presented similar efficiency. The adsorption isotherms of EE and MB onto cryogels fitted with sigmoidal and Freundlich adsorption models, indicating higher affinity for aerogels with 5% CNC-SO4. Cryogels could be recycled 10 and 5 times, respectively, for MB and EE adsorption/desorption under flow without losing efficiency, disclosing their potential for preconcentration of pollutants, and environmental remediation. (AU)

• FAPESP's process: 15/25103-2 - Magnetic stimuli in biotechnological processes
• Grantee: Denise Freitas Siqueira Petri
• Support Opportunities: Regular Research Grants