The use of encapsulation as a proposed solution to avoid problems encountered with conventional materials in powder form: Application in methylene blue removal from aqueous solutions

Abstract

The Ziziphus jujuba stones chemically modified with orthophosphoric acid (PZJS), then encapsulated with sodium alginate (BZJS1 and BZJS2) were used for organic dye adsorption.In this context, the basic dye methylene blue (MB) was chosen as a test molecule. The characteristics of the prepared beads were examined by different characterization techniques, such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray diffraction (EDX), X-ray fluorescence (XRF), Thermogravimetr ic analysis (TGA) and Brunauer-Emmett-Teller method (BET) with nitrogen adsorptiondesorption isotherm at 77°K. In a batch system, initial pH (2-12), temperature (10, 25, 30 and A c c e p t e d m a n u s c r i p t 2 40 °C), initial concentration (50-200 mg/L), contact time, salt and organic compound effects were studied. The obtained results showed that the maximum MB adsorption amounts were 737.13 mg/g and 660.12 mg/g onto BZJS1 and BZJS2 at ambient temperature respectively, showing that the prepared materials are more efficient than most of the other adsorbents.Moreover, experimental data modeling showed that the adsorption process followed the Redlich-Peterson model. Regarding kinetics modeling, pseudo-first-order (PFO), pseudosecond-order and Pseudo-nth order models were used to correlate experimental data, demonstrating that a mass transfer equation (PFO) could describe MB adsorption. Thermodynamic Parameters were also evaluated, demonstrating that the MB adsorption process was achievable, spontaneous and exothermic. The regeneration study showed that both of the beads had excellent adsorption efficiency even at the sixth cycle for the two beads, 92.01 and 82.88 for BZJS1 and BZJS2, respectively. From this and in view of a future implementation at industrial scale, encapsulation by sodium alginate polymer can be therefore promisingly proposed as a solution to avoid the problems of conventional materials in powder form, such as the difficulty of regeneration, performances and mass loss during the recovery step of the powder from the medium.

Adsorption of a Cationic Dye Crystal Violet onto a Binary Mixture of Forest Waste Biopolymer: Advanced Statistical Physics Studies

“…After adsorption balance (adsorbentadsorbate), the experimental data points were fitted with four mathematical simulation models, Freundlich, Langmuir, Redlich-Peterson and Sips to precisely analyze the interaction between the Cupcar-H3PO4 and the CV color. Table 2 describes these isotherm models and the obtained models parameters [41].…”

“…In this regard, biosorbents synthesized from lignocellulosic residues have been widely used as adsorbents to treat colored effluents, because of their very large porous structure, large surface area and high adsorption capacity. Among these adsorbents, we can mention: dates kernels [14], apple pulp [15], olive kernels [16],peach kernels [17], corncobs [18], coffee beans [19] and coffee grounds [20,21], Tea waste [22], bagasse [23], coconut shell [24], apricot kernels [25], fungi [26], algae [27], chitosan [28], bacteria [29] and in recent times, Ash of Cassia fistula seeds [30], coconut shell and coal ash [31], Stipatenassicima fibers [32], cones of Pinus brutia [33], wild carob [34], LDHs [35], acid treated Cupressus semperirens cones pomegranate peel [36], and more recently, pectin from orange industry residues [37], polyacrylamide-diatomite (PAA-D) [38], chitosan vermiculite beads [39], Orange Peel treated with H3PO4 [40] and jujuba stones [41].…”

Statistical physics modelling of azo dyes biosorption onto modified powder of Acorus calamus in batch reactor

“…Among these adsorbents, we can mention among others: date stones [10], apple skin [11], olive stones (10), peach stones [13], corn cobs [14], coffee beans [15], and coffee grounds [16,17], Tea waste [18], bagasse [19], coconut shell [20], apricot stones [21], fungi [22], algae [23], chitosan [24], bacteria [25]. Also, in recent times, Ash of Cassia fistula seeds [26], rice husk [27] , coconut shell and coal ash [28], Stipa tenassicima fibers [29], cones of Pinus brutia [30], wild carob [31], LDHs [32] and acid treated Cupressus semperirens cones pomegranate peel [33], as well as pectin from orange industry residues [34], polyacrylamidediatomite (PAA-D) [35], Fe3O4 [36], chitosan vermiculite beads [37], Pseudoevernia furfuracea [8], Orange Peel treated with H3PO4 [38] and particles of Ziziphus jujuba stones (BZJS1) [39].…”

“…The potential of PACK, an easily available and low-cost material, to be used as an alternative biosorbent material for the removal of a dye, MB, from aqueous solutions was therefore confirmed. [39] pectin from orange industry residues (alginate beads 398.40 [34] graphene oxide 357.14 [61] OP-H3PO4 307.63 [38] Palm fiber-activated carbon 278 [59] Activated carbon from Mangosteen fruit peel 230 [62] Wild carob-activated carbon 218 [63] Chitosan flakes-activated carbon 144 [64] Fe3O4 particle 20.40…”