Modified hydrophobic and oleophilic polyurethane sponge for oil absorption with MIL-53

Isha Riyal; Gunjan Joshi; Himani Sharma; Charu Dwivedi

doi:10.1016/j.envres.2023.116982

Modified hydrophobic and oleophilic polyurethane sponge for oil absorption with MIL-53

Environ Res. 2023 Nov 15;237(Pt 2):116982. doi: 10.1016/j.envres.2023.116982. Epub 2023 Aug 30.

Authors

Isha Riyal¹, Gunjan Joshi¹, Himani Sharma², Charu Dwivedi³

Affiliations

¹ Department of Chemistry, Doon University, Dehradun-248001, India.
² Department of Physics, Doon University, Dehradun-248001, India.
³ Department of Chemistry, Doon University, Dehradun-248001, India. Electronic address: cdwivedi.ch@doonuniversity.ac.in.

PMID: 37657607
DOI: 10.1016/j.envres.2023.116982

Abstract

A hydrophobic composite sponge (HPCS) is developed for the first time using the dip coating and drying method in an effort to remove organic contaminants like toluene and various oils from water. We employed a polyurethane (PU) sponge, which is reasonably priced, easily accessible, high mechanical strength and a suitable porous substrate on which the hydrophobic composite of MIL-53(Al) along with PDMS was anchored. A crystalline metal organic framework (MOF), MIL-53(Al), with adjustable porosity, functionality, and hydrophobicity is used for oil absorption. Polydimethylsiloxane (PDMS) is utilized to increase the hydrophobicity of MIL-53(Al). The MIL-53(Al)@PDMS composite was used to the produce a sponge having high hydrophobicity and oleophilicity. In contrast to PU sponge, which has a low water contact angle (79.64°), the hydrophobic composite sponge showed a wide range of oil absorption capacity (12-50.5 g/g), a very low amount of water absorption (0.84 g/g), and water contact angle of 128.13°. This hydrophobic composite performed phenomenally by separating out various oils and solvents from water even in varying ionic strengths. Moreover, the recyclability of the formed composite was also performed resulting into 6-20 cycles for different oils and solvents. The synthesized hydrophobic composite sponge was characterized using FT-IR, XRD, TEM, surface area analysis, FESEM, XPS, TG analysis and contact angle measurement. Furthermore, the materials used in the synthesis of composite are non-toxic and do not harm the environment, resulting in no greenhouse gas emissions making our composite environmentally friendly.

Keywords: Climate change; Composite; Hydrophobic; Metal organic frameworks; Oleophilic; Sponge; oil absorption.