REMOVAL OF INDIGO CARMINE DYE (IC) BY BATCH ADSORPTION METHOD ONTO DRIED COLA NUT SHELLS AND ITS ACTIVE CARBON FROM AQUEOUS MEDIUM

Natural cola nut shells and its active carbons were used to remove indigo carmine dye from aqueous solution using batch adsorption test. The effect of pH, contact time (t), adsorbent dose (m) and initial concentrations (Co) were investigated. The equilibrium adsorption data were analyzed by Langmuir, Freundlich, Tempkin and Dubin-Kaganer-Raduskushkevich classical isotherm models. This equilibrium data best fits with all the four isotherm models for cola nut shells. Langmuir and Freundlich equations correlated well with data obtained using activated carbon based H3PO4 while Freundlich and Tempkin best agreed with activated carbon based KOH. The kinetics of indigo carmine dye was discussed by pseudo-first order, pseudo-second order, Elovich and Intra-particle diffusion models. The pseudo-second order kinetic model equation fitted best to the data from all the three adsorbents. Elovich fitted best with data obtained using activated carbon based H3PO4 while intra-particle diffusion model for activated carbon based KOH. D-K-R shows that adsorption process was chemisorption for all the three adsorbents. Natural cola nut shells and activated carbon based KOH show higher adsorption capacities with indigo carmine compared to activated carbon based H3PO4. The results indicated that these shells and it active carbon can be used as an effective and low-cost adsorbent to remove indigo carmine from aqueous solution

Potential of VIS-NIR spectroscopy to characterize and discriminate topsoils of different soil types in the Triffa plain (Morocco)

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Removal of metallic trace elements (Pb2+, Cd2+, Cu2+, and Ni2+) from aqueous solution by adsorption onto cerium oxide modified activated carbon

peer reviewedThe equilibrium and kinetic studies of removal of Pb2+, Cd2+, Ni2+, and Cu2+ metal ions were carried out using activated carbon prepared from palm kernel shell and doped with CeO2 (Ce/AC). The obtained material carbon was characterized by XRD which showed some crystalline traces of CeO2, SEM displaying the porous texture with spherical pores and the determination of pH of point of zero charge (pHPZC) which was found to be equal to 6. The contact time and adsorbate were thoroughly investigated. The maximum adsorption depends inversely on the hydrated metal radius. This observation was confirmed by calculating the formation energies (ΔH(M(OH)2)) of M(OH)2. The metal ionic radii were acting on calculated sorption capacity and that sorption efficiency related to ionic radii of metal was as follows: R(Ni2+) ≤ R(Cd2+) < R(Cu2+) < R(Pb2+). The texture and morphology of the material after sorption were affected by the metallic ion nature as observed by SEM. The kinetic studies showed that the rate constant (k2) of pseudo-second-order model decreased with the increase of the hydrated cations radii, while the rate constant of intraparticle diffusion increased with the increase of the ionic radii. The Freundlich isotherm model best fit the experimental sorption data for all the metallic ions

Batch Adsorption of Ammonium Ions from Synthetic Wastewater using Local Cameroonian Clay and ZnCl2 Activated Carbon

Local Cameroonian clay and ZnCl2 activated carbon were used for the adsorption of NH4+ ions from synthetic wastewater. The Batch adsorption experiments were conducted and optimal conditions were established to better understand the effects of solution pH, initial ammonium ions concentration, adsorbents dose and contact time. The time-dependent experimental studies showed that, the adsorption quantity of ammonium ions increases with initial concentration and decrease with adsorbents dose. The ammonium ions uptake was very fast and reached equilibrium within 10 and 15 min with ZnCl2 activated carbon and Soukamna Clay. Both ZnCl2 activated carbon and Soukamna Clay gave best adsorption results at pH 2 and 6. FTIR, powder X-ray diffraction, chemical analysis, TGA and DSC analysis were used to characterize the Soukamna Clay. The adsorption equilibrium were confronted using Langmuir, Freundlich, Temkin and DndashKndashR isotherm models and their applicability were judged by comparing the correlation coefficients and the experimental calculated quantities. The DndashKndashR, Temkin and Freundlich isotherms models best #64257tted to the experimental data for Soukamna Clay while the DndashKndashR isotherm model fitted well with ZnCl2 #821 AC. The adsorption mechanism was analyzed using the pseudo-#64257rst order, pseudo-second order, the Elovich kinetic and intra-particle diffusion models. The pseudo-second order kinetic model correlates better the experimental and calculated data than the other three kinetic models which suggests that, chemisorption was more dominant with both adsorbents. Soukamna Clay and ZnCl2 #821 AC used successfully as a low-cost adsorbent for the removal of NH4+ ions from aqueous solution can have promising application in industrial wastewater treatment

ACTIVATED CARBON BASED CANARIUM SCHEWEINFURTHII SHELLS FOR THE REMOVALOF NITRATE IONS FROM AQUEOUS SOLUTION

The activated carbons preparation conditions from canarium scheweinfurthii shells were investigated. The two most influenced factors: the H3PO4 concentration (30 to 60 %), and the activation temperature (300 to 700°C) were studied at constant impregnation ratio of 1/1. The analysis of experimental data showed that, the optimum preparation conditions were achieved for an activation temperature of 700°C and H3PO4 concentration of 30 %. Prior to the preparation, the proximate analysis of the precursor gave, 32.70 %, 2.10 %, 63.34 % and 1.86 % for the fixed carbon, moisture, volatile matter and ash contents respectively. The iodine number was found to be 436.8mg/g and the BET surface area of 397.5 m2/g. According to the batch adsorption study, the maximum quantity of nitrate ions adsorbed was 7.40 mg/g at the following reaction conditions: 0.05 g of adsorbent, 10 mg/L of adsorbate concentration, pH of 2 and 40 minutes of contact time