EcoFlex sponge with ultrahigh oil absorption capacity

A paraffin microsphere-templated 3D porous EcoFlex sponge was prepared to selectively absorb oil or chemicals from water. The technology for producing this EcoFlex sponge does not need complicated synthesis processes or instruments, and materials applied in this work are eco-friendly. Therefore, this sponge can be employed in environmental field. EcoFlex sponges showed high hydrophobicity (contact angle 140o -143o) and oleophilicity. The developed sponge exhibits a porous three-dimensional framework inside with excellent internal connectivity, which contributes both better absorption capacity and faster absorption rate. For instance, the absorption capacity for chloroform can reach to 3400 wt%. The adsorption capacity of the sponge was optimized using different size of paraffin microspheres and these sponges exhibits relatively high absorption capacity in a short time (2 min). The volume of sponge expands in some oils and organic solvents, the volume increasing capacity for hexane can reach 2200%. This sponge also has great recovery capability and durability; it keeps its original shape and absorption capacity after 15 cycles of oil absorption and compression.