Kinetics and thermodynamics of adsorption of methylene blue by a magnetic graphene-carbon nanotube composite

Application of Magnetic Graphene Nanoparticles for Determination of Organophosphorus Pesticides Using Solid-Phase Microextraction

“…The XRD pattern of G/Fe 3 O 4 shows a broad peak corresponding to the (002) reflection of graphene at 26°, suggesting that the samples are very poorly ordered along the stacking direction. This fact solidly confirmed that GO was successfully reduced to graphene nanosheets [29]. Except the diffraction peak at 2θ = 26° resulting from graphene, all the other significant diffraction peaks of the G/Fe 3 O 4 sample matched well with data from the JCPDS card (19-0629) for Fe 3 FT-IR spectra of GO, Fe 3 O 4 , and G/Fe 3 O 4 nanoparticles are shown in Fig.…”

Kinetic and Thermodynamics of Methylene Blue Adsorption onto Zero Valent Iron Supported on Mesoporous Silica

“…The negative value of ∆G° indicated the feasibility of the process and the spontaneous nature of the adsorption with a high preference of MB onto NZVI/MSNs. The values of ∆G° were found to decrease as the temperature increased, indicating less driving force and hence resulting in less adsorption capacity [30]. Observed thermodynamic parameters indicate that the process was spontaneous and endothermic.…”

Hybrid Monolith of Graphene/TEMPO-Oxidized Cellulose Nanofiber as Mechanically Robust, Highly Functional, and Recyclable Adsorbent of Methylene Blue Dye

“…However, higher content of CNFs showed little improvement in dye adsorption capacity and specific surface area, which could be explained as follows: higher incorporation of CNFs leads to aggregation into pore orifice thus reducing the full surface area coverage of hybrid monolith for dye molecules. Based on Table S4, candidate hybrid adsorbent showed notable adsorption performance compared with other reported work such as high cost carbon nanotube (CNT) [13], graphene/CNT monolith [33], MWCNT aerogel [51], graphene by toxic hydrazine [27], graphene/luffa sponge [12], thiourea assisted graphene sponge [31], polydopamine microspheres [23], polyaniline hydrogel [26], magnetic particle based graphene composite [9,19,[34][35][36][37][38], graphene coated biochar [40], and graphene oxide/calcium alginate [14]; for more comparison see Table S4.…”

“…Among the various treatment techniques such as biological treatment [4], ozone oxidation [4], catalytic degradation [5], photocatalytic oxidation [6], coagulation and flocculation [3], nanofiltration membrane [7], and unsaturated polyester resins [8], adsorption is the most attractive due to competency for variety of organic dyes, insensitivity to toxic pollutants [9], efficiency for low concentration range [10], easiness of operating, and being economical process [9,[11][12][13][14][15][16][17][18][19][20][21]. Carbon materials in the form of activated carbon are historically dominant for dye decontamination in view of chemical stability, high surface area, and functional active sites [16,20,[22][23][24][25][26].…”

“…Likewise, oxygen functional groups make this nanomaterial behave like polymer and form variety of covalent or noncovalent bonding reactions [32]. Recently, by taking advantage of fundamental chemistry of graphene oxide a diverse range of functional adsorbents have been formulated, for instance, chemically reduced graphene [27], sponge [12,31], hydrogels/aerogels [18,33], and magnetically separable adsorbents [9,19,[34][35][36][37] to improve its competency and recollection issues. However, it suffers from low structural and adsorption capacities, while use of external magnate is practically not feasible as well.…”