The optimization effect of different parameters on the super hydrophobicity of prickly-shaped carbonyl iron particles

Durable superhydrophobic/superoleophilic melamine foam based on biomass-derived porous carbon and multi-walled carbon nanotube for oil/water separation

In the present study, fabrications of two eco-friendly superhydrophobic/superoleophilic recyclable foamy-based adsorbents for oil/water mixture separation were developed. Hierarchically biomass (celery)-derived porous carbon (PC) and multi-walled carbon nanotube (MWCNT) were firstly synthesized and loaded on pristine melamine foam (MF) by the simple dip-coating approach by combining silicone adhesive to create superhydrophobic/superoleophilic, recyclable, and reusable three-dimensional porous structure. The prepared samples have a large specific surface area of 240 m²/g (MWCNT), 1126 m²/g (PC), and good micro-mesoporous frameworks. The water contact angle (WCA) values of the as-prepared foams, PC/MF and MWCNT/MF, not only were 159.34° ± 1.9° and 156.42° ± 1.6°, respectively but also had oil contact angle (OCA) of equal to 0° for a wide range of oils and organic solvents. Therefore, PC/MF and MWCNT/MF exhibited superhydrophobicity and superoleophilicity properties, which can be considered effective adsorbents in oil/water mixture separations. In this context, superhydrophobic/superoleophilic prepared foams for kind of different oils and organic solvents were shown to have superior separation performance ranges of 54-143 g/g and 46-137 g/g for PC/MF and MWCNT/MF, respectively, suggesting a new effective porous material for separating oil spills. Also, outstanding recyclability and reusability of these structures in the ten adsorption-squeezing cycles indicated that the WCA and sorption capacity has not appreciably changed after soaking into acidic (pH = 2) and alkaline (pH = 12) as well as saline (3.5% NaCl) solutions. More importantly, the reusability and chemical durability of the superhydrophobic samples made them good opportunities for use in different harsh conditions for oil-spill cleanup.

Investigation of grafting silane coupling agents on superhydrophobicity of carbonyl iron/SiO2 particles for efficient oil/water mixture and emulsion separation

The present study demonstrated the wettability properties of grafting silane coupling agents on carbonyl iron (CI)/SiO₂ particles for efficient oil/water mixture and emulsion separation. CI particles were first reacted with Tetraethoxysilane (TEOS) to create a magnetic component. Then, CI/SiO₂ particles were altered by 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FAS) and Hexamethyldisilazane (HDMS) to create magnetic superhydrophobic/superoleophilic, recyclable, and reusable sorbent powders. The water contact angle (WCA) values of the as-prepared particles, CI, CI/SiO₂, CI/SiO₂@FAS, and CI/SiO₂@HMDS, were 5.4° ± 1.3°, 6.4° ± 1.4°, 151.9° ± 2.1°, and 170.1° ± 1.1°, respectively. In addition, the oil contact angles (OCAs) of a variety of oils were found to be equivalent to 0°. Hence, superhydrophobic/superoleophilic particles for kind of different oils were shown sorption capacities of 1.7-3.1 g/g and 2.5-4.3 g/g for CI/SiO₂@FAS, and CI/SiO₂@HMDS, respectively. Besides, for 1%w/w hexane/water emulsion separation efficiency higher than 99%, the lowest mass was obtained at 50 and 200 mg for CI/SiO₂@HDMS and CI/SiO₂@HDMS, respectively, suggesting a new effective material for separating tiny oil droplets. Also, the reusability and chemical durability of the superhydrophobic samples made them a prime candidate for use in different harsh conditions.

Simple one-step synthesis of urchin-like Fe-Mn nanostructures via statistical design and their effects on the morphology

In the current investigation, a new urchin-like nanostructure using an authorized one-pot precipitation technique was synthesized using Taguchi statistical design. The effect of factors, including the concentration of FeSO4⋅7H2O, KMnO4, NaOH, and reaction temperature, on the diameter-to-length ratio of the nanoneedles and the regularity or irregularity morphology of other samples, was investigated. KMnO4 and FeSO4⋅7H2O, with a contribution of 32.62% and 30.9%, had the most substantial effect on the nanoneedles' diameter. The surface morphology and chemical composition of the as-prepared samples were studied using field emission scanning electron microscopy, X-ray diffraction, and energy dispersive spectroscopy (EDX) analyses. The length and needle diameter was obtained 140 and 17 nm, respectively. The result of BET analysis for the highest and the lowest value of D/L shows that the smallest ratio of diameter to length has a high specific surface area. The results show that sample S4 has a particular surface area of 74 m2/g, much more than S3 (25 m2/g). The estimated crystallite size in synthesized S3 and S4 samples are 41.64 and 26.49 nm, respectively.