Populus seed fibers as a natural source for production of oil super absorbents

The genus Populus, which includes poplars, cottonwoods and aspen trees, represents a huge natural source of fibers with exceptional physical properties. In this study, the oil absorption properties of poplar seed hair fibers obtained from Populus nigra italica when tested with high-density motor oil and diesel fuel are reported. Poplar seed hair fibers are hollow hydrophobic microtubes with an external diameter between 3 and 12 μm, an average length of 4 ± 1 mm and average tube wall thickness of 400 ± 100 nm. The solid skeleton of the hollow fibers consists of lignocellulosic material coated by a hydrophobic waxy coating. The exceptional chemical, physical and microstructural properties of poplar seed hair fibers enable super-absorbent behavior with high absorption capacity for heavy motor oil and diesel fuel. The absorption values of 182–211 g heavy oil/g fiber and 55–60 g heavy oil/g fiber for packing densities of 0.005 g/cm3 and 0.02 g/cm3, respectively, surpass all known natural absorbents. Thus, poplar seed hair fibers obtained from Populus nigra italica and other trees of the genus Populus are an extremely promising natural source for the production of oil super absorbents.

► Morphology of poplar seed fibers consisting of hollow hydrophobic microtubes. ► Oil sorption of poplar seed fibers surpasses known natural oil sorbent materials. ► High chemical stability of poplar seed fibers in polar and nonpolar solvents. ► Up to now the poplar seed fibers are treated as a waste. ► Can be easily used as natural source for production of oil super sorbent.