Polydimethylsiloxane/carbonized bacterial cellulose sponge for oil/water separation

Abstract

Frequent oil spills from ships at sea have caused irreversible damage to the Marine environment. It is particularly important to develop environmentally friendly sorbent materials with special wettability and recyclability for oil/water separation. The polydimethylsiloxane/carbonized bacterial cellulose sponge (PDMS/CBC sponge) is self-assembled with PDMS as the matrix skeleton and CBC as the surface filler. With adding CBC, the elasticity and hydrophobicity of the PDMS composite sponge have been significantly improved. The PDMS/CBC sponge can be compressed to 80% deformation with only 1.45 MPa of force, and introducing of CBC makes the PDMS/CBC sponge more flexible. Even after 50 times of pressing, it can restore its original appearance and keep the internal channels from collapsing. The water contact angle of the PDMS/CBC sponge can reach 146.8°. The micro-nano structure substance CBC added into the surface of the low surface energy substance increases the roughness of the sponge and makes the sponge more lipophilic, which also makes the PDMS/CBC sponge have an excellent sorption ability of oil. And the sorption capacity of organic solvent/oil is from 300% to 900%. This super elasticity also allows material and regenerate by simple squeezing, and the sorption efficiency can reach 99.3% of the first time after 30 recycles. In addition, the PDMS/CBC sponge also shows a good sorption effect in an acid-base salt environment.