Adsorption of methylene blue by a high-efficiency adsorbent (polydopamine microspheres): Kinetics, isotherm, thermodynamics and mechanism analysis

Synthesis and characterization of SnO2/(NH4)2‐SnCl6 nanocomposites loaded on activated carbon and its application for adsorption of methylene Blue and Orange G

“…This results is explained by the fact that following adsorption of first layer of charged dyes on adsorbent and formation of semi-capacitor, hinder form more layer adsorption via repulsive force among layer [43] The effect of isotherm shape has been discussed with a view to predict whether an adsorption system is favorable or unfavorable which in Langmuir isotherm represent by R L value to separation factor or equilibrium parameter. [44] The i.e., whether the process is unfavorable (R L > 1), or linear (R L = 1), or favorable (0 < R L < 1), or irreversible (R L = 0) and as results show R L values were in the range of 0 < R L < 1 (Table 4) which support high efficiency of this model for [48] Activated Carbon (walnut shells) MB 315.0 1440 [49] CuO-Nanoparticles Loaded on Activated Carbon MB 10.55 15 [50] PDA microspheres MB 90.70 100 [51] MWCNTs filled with Fe 2 O 3 particles MB 42.90 60 [52] Ag-Nanoparticles Loaded on Activated Carbon MB 71.43 15 [21] Humic Acid-coated Fe 3 O 4 -NP (HA-Fe 3 O 4 ) MB 93.08 27 [53] Activated Carbon of Thespesia Populnea Pods OG 9.120 180 [54] Bagasse Fly Ash OG 18.79 240 [10] explanation of data in single (MB and OG) and binary system (MB-OG) on the SnO 2 /(NH 4 ) 2 -SnCl 6 -NCs-AC. Freundlich parameters (K F and n) indicate whether the nature of sorption is either favorable or unfavorable and accordingly 1 < n < 10 imply favorable sorption and its value closer to 1 suggest more uniform adsorbent.…”

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]. Recently, graphene oxide (GO) produced by soft chemistry techniques arouse as highly efficient [10,15,21,[27][28][29] and low cost carbon nanoadsorbent [11,30] followed by various carbon materials including single/or multiwall carbon nanotubes, since it owns many superior properties such as large theoretical surface area (2630 m 2 /g) [31], mechanical flexibility, high charge carrier mobility, and chemical stability [32].…”

Kinetics adsorption study of the ethidium bromide by graphene oxide as adsorbent from aqueous matrices

“…In general, at kinetic studies, the pseudo-first-order kinetic model equation is expressed as [24][25][26] …”