Assessment of sorption kinetics of carbon nanotube‐based composite foams for oil recovery application

Abstract

Sorption kinetics of pollutant oils, such as kerosene, virgin naphtha, crude oil, and pump oil, into porous siloxanic foams filled with carbon nanotubes (CNTs) are investigated. Both, pristine and functionalized, CNTs are used as foam fillers. Among all, the foam filled with pristine CNT shows a poor affinity with water and high sorption rate in light oils, in which it achieves the highest absorption values (7991 mg g−1 after 660 s and 6685 mg g−1 after 420 s, respectively, in virgin naphtha and kerosene). The kinetic data are described by the pseudo‐first order, pseudo‐second order, Elovich and intraparticle diffusion models. Results show that chemisorption processes are rate limiting the sorption step. In fact, pseudo‐second order model better represents the equilibrium isotherm data. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47374.

Preparation of polypropylene/high‐melt‐strength PP open‐cell foam for oil absorption

“…An apparent intraparticle diffusion stage, defined as diffusion after the early stages of the absorption, [ 37 ] was observed between 30 min and 220 min. [ 38 ] The high viscosity or high surface tension of motor oil and sunflower oil prevents these oils from penetrating the foam; therefore, no intraparticle diffusion stage was observed and the oil absorptions were much lower than that of gasoline.…”

“…The higher the viscosity, the higher the adsorption rate constant k 2 , as has been observed in the literature. [ 38 ]…”

Assessment of Arundo donax Fibers for Oil Spill Recovery Applications

“…The results indicate a suitable adsorption efficiency (in terms of pollutant uptake speed) and oil selectivity. These two factors represent an effective and reliable precondition for the use of these natural fibers on the industrial scale for oil spill recovery, thanks also to the cheapness of the sorbent material, which can offset the sub-optimal adsorbing performance with respect to some new emerging materials [36,38,39]. According to [40], natural fibers are characterized by an acceptable sorption efficiency and capacity for different kinds of oil.…”

“…Baker et al [41] evidenced that the water selectivity of a membrane is related to the microstructure and chemistry of the material. Piperopoulos et al [38], examining carbon nanotubes sponges for oil recovery applications, defined the sorption mechanism on porous structure in three main steps: (i) Oil molecules diffuse from bulk liquid and wet the sorbent; (ii) at the same time, physical (van der Waals forces between adsorbate molecules and the adsorbent surface) and/or chemical interactions take place, (iii) increasing the sorption time; liquid diffusion occurs with difficulty due to the limited hydrophilic or oleophilic (depending on the pollutant) active sites, not filling the internal micropores.…”

Highly efficient reusable superhydrophobic sponge prepared by a facile, simple and cost effective biomimetic bonding method for oil absorption

“…3D hydrophobic materials, which have a large storage capacity, can absorb and desorb oil immediately. However, the synthesis of materials, such as carbon nanotube (CNT) foam, rubber/graphene composite materials, cellulose aerogels and graphene aerogels, faces the challenges of complicated operation, high cost and causing environmental pollution 16 , 17 . Among these 3D materials, sponges not only possess the advantages of porous structure, great flexibility, and commercial availability 18 but can also be chemically modified 19 .…”