Superhydrophobic Silanized Melamine Sponges as High Efficiency Oil Absorbent Materials

Abstract

Superhydrophobic sponges and sponge-like materials have attracted great attention recently as potential sorbent materials for oil spill cleanup due to their excellent sorption capacity and high selectivity. A major challenge to their broad use is the fabrication of superhydrophobic sponges with superior recyclability, good mechanical strength, low cost, and manufacture scalability. In this study, we demonstrate a facile, cost-effective, and scalable method to fabricate robust, superhydrophobic sponges through the silanization of commercial melamine sponges via a solution-immersion process. The silanization was achieved through secondary amine groups on the surface of the sponge skeletons with alkylsilane compounds, forming self-assembled monolayers on the surface of sponge skeletons. This resulted in our ability to tune the surface properties of the sponges from being hydrophilic to superhydrophobic with a water contact angle of 151.0°. The superhydrophobic silanized melamine sponge exhibited excellent sorption capacity for a wide range of organic solvents and oils, from 82 to 163 times its own weight, depending on the polarity and density of the employed organic solvents and oils, and high selectivity and outstanding recyclability with an absorption capacity retention greater than 90% after 1000 cycles. These findings offer an effective approach for oil spill containment and environmental remediation.

Designing durable and flexible superhydrophobic coatings and its application in oil purification

“…Durable superhydrophobic coatings have been reported recently, 26 such as acrylic polyurethane based coating, 27 textured surface obtained by chemical etching, 28,29 surfaces template from innately microstructured hydrogel matrix, 30 block-copolymer-based thin-film patterning, 31 combination of rodlike palygorskite and organosilanes via spray-coating, 32 fluorine-free polysiloxane/multiwalled carbon nanotubes, 33 titanium dioxide materials with special wettability, 34 or various coatings fabricated on fabrics/sponges/cotton. [35][36][37][38][39][40] However, most of the reported surfaces are not durable enough, as they can only resist abrasion against wipes, 28 fine sandpaper (e.g., 800, 1000, 2000 grid), mild droplets/sand impinging, 30,31 or were easily disabled after a short distance (i.e., less than 5 m) of abrasion. 27,29,[41][42][43] Besides, the mechanical stability may be simply due to the fact that the coating thickness is too thick to be worn out completely to expose the substrate surface underneath the superhydrophobic coating.…”

Inorganic Micelles (Hydrophilic Core@Amphiprotic Shell) for Multiple Applications

“…Due to the increasing requirements for environmental and water remediation, the selective separation of oil spills (or organic solvents) from water using polymer membranes/febrics, [ 1,2 ] metal meshes, [ 3,4 ] and sponges [ 5,6 ] has been the subject of extensive research in recent years. There are several methods for fabricating oil/water separation materials.…”

Polymeric Sorbents for the Collection of Oil and Oil Products from the Surface of Reservoirs: a 2000–2017 Review of the English-language Literature (Part 2)

“…В статье [13] предложен простой и экономи-чески эффективный способ изготовления супер-гидрофобных губок силанизацией коммерческих меламин-формальдегидных губок погружением в раствор алкилсилановых соединений. Сила-низация осуществлялась по вторичным амино-группам на поверхности губки с образованием самоорганизованных поверхностных монослоёв.…”

“…Это затрудняет сравнение и выявление лучшего нефтесорбента. Так, мак-симальная сорбционная ёмкость в данной части обзора составляла 163 г/г (супергидрофобная силанизированная меламиновая губка [13]), но это сорбция хлороформа. Следующая за ней величина, 160 г/г (полиуретановая губка, по-крытая оксидом графена [12]), также относится к хлороформу.…”