Novel Hydrophobic Polyvinyl-Alcohol Formaldehyde Sponges: Synthesis, Characterization, Fast and Effective Organic Solvent Uptake from Contaminated Soil Samples

In the present research work, PVFTX-100, PVFSDS, and PVFT-80 sponges were prepared using polyvinyl-alcohol (PVA) with surfactants triton X-100/sodium dodecyl sulfate (SDS)/Tween 80, respectively, for the removal of organic solvents from polluted soil/water samples. All three obtained sponges were further made hydrophobic using dodecyltrimethoxysilane (DTMS). The prepared sponges were characterized using different spectroscopic techniques and SEM analysis. The peaks obtained near 1050 cm⁻¹ and 790 cm⁻¹ were attributed to Si-O-C and alkyl side chain C-H stretching vibration that confirmed the formation of desired sponges. The SEM images showed the random roughness with a number of protrusions on sponge surfaces, which further played an important role in the absorption and retention of organic solvents molecules. The Sears method was chosen to calculate the surface area and pore volume of all the synthesized sponge samples. Among all three prepared sponges, the PVFTX-100 sponge showed a high pore volume and large surface area, with a maximum percentage absorption capacity of 96%, 91%, 89.9%, 85.6%, and 80 for chlorobenzene, toluene, diesel, petrol, and hexane, respectively, after eightcycles. The organic solvent uptake using PVFTX-100, PVFSDS, and PVFT-80 sponges is quite a unique and simple technology, which could be employed at a large scale for contaminated soil/water systems.