scholarly journals Adsorption of Malachite Green by Jordanian Diatomite Ores: Equilibrium Study

Author(s):  
Emad El Qada

The focal theme of this work is to assess the ability of Jordanian diatomite to treat MG-bearing effluents. Effects of several experimental parameters namely, particle size of diatomite, pH and initial MG concentration were investigated through liquid-phase adsorption processes. Several equilibrium isotherm models were applied. It was found that initial MG concentration, pH and particle size of diatomite had a significant effect on the adsorption process. MG uptake has increased from 99.3 mg/dm3 to 898.7 mg/dm3 over the whole concentration range. A high percentage of MG removal (99.6%) was achieved as the diatomite particle size decreased from 500-710μm to 125-250μm. The optimum pH for the removal of MG was=9. Freundlich model was satisfactorily applied to the experimental data.

2010 ◽  
Vol 7 (1) ◽  
pp. 157-165 ◽  
Author(s):  
Tariq S. Najim

The batch removal of Cu(II) from aqueous solution using poly (furfural-acetone), (PFA) as adsorbent was investigated in this study. The influences of initial Cu(II) ion concentration (10 to 120 ppm), pH (4-8) and contact time have been reported. Adsorption of Cu(II) is highly pH-dependent and the result indicate that the optimum pH for the removal was found to be 6. At this pH a small amount of PFA, 2 g/L, could remove as much as 97% of Cu(II) from a solution of initial concentration 10 ppm. It was observed that an increase in initial concentration of Cu(II) leads to decrease in percent removal of Cu(II) and increase in amount of Cu(II) adsorbed per unit mass of PFA. The adsorption process of Cu(II) is tested with four isotherm models, Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D-R). It was found that all models were applicable and the maximum adsorption capacity was found to be 13.66 mg/g. From the isotherm constants it was confirmed that, the sorption process was physisorption.


2018 ◽  
Vol 7 (3) ◽  
pp. 1904
Author(s):  
Gunjal Karania ◽  
Paridhi Singh ◽  
C R. Girish

The present work explores the potential of tea fibre waste as an adsorbent to remove phenol and nickel from wastewater in both single and binary component mode. The properties of the tea fibre such as surface area, pore volume and particle size were improved by treating with hydrochloric acid. The isotherm models were verified for single component system to find the adsorption mechanism. The equilibrium data were obeying Freundlich model. The simultaneous adsorption of two pollutants were carried out in order to evaluate the interaction mechanism such as synergic, antagonistic or non-interaction effect. It was observed that overall the system was exhibiting synergistic type of behavior.  


2015 ◽  
Vol 12 (1) ◽  
pp. 148-156
Author(s):  
Baghdad Science Journal

The subject of this research involves studying adsorption to removal herbicide Atlantis WG from aqueous solutions by bentonite clay. The equilibrium concentration have been determined spectra photometry by using UV-Vis spectrophotometer. The experimental equilibrium sorption data were analyzed by two widely, Langmuir and Freundlish isotherm models. The Langmuir model gave a better fit than Freundlich model The adsorption amount of (Atlantis WG) increased when the temperature and pH decreased. The thermodynamic parameters like ?G, ?H, and ?S have been calculated from the effect of temperature on adsorption process, is exothermic. The kinetic of adsorption process was studied depending on Lagergren ,Morris ? Weber and Rauschenberg equations.


2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Emmanuel Nyankson ◽  
Jonas Adjasoo ◽  
Johnson Kwame Efavi ◽  
Reuben Amedalor ◽  
Abu Yaya ◽  
...  

In this work, zeolite (Z) and Z-Fe3O4 nanocomposite (Z-Fe3O4 NC) have been synthesized. The Fe3O4 nanoparticles were synthesized using the extract from maize leaves and ferric and ferrous chloride salts and encapsulated into the zeolite framework. The nanocomposite (Z-Fe3O4 NC) was characterized using X-ray diffractometer (XRD), Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray (EDX) spectroscopy, and scanning electron microscopy (SEM). The potential of Z-Fe3O4 NC as an adsorbent for removing methylene blue molecules (MB) from solution was examined using UV-Vis and kinetic and equilibrium isotherm models. The adsorption data fitted best with the pseudo-second-order model and Weber and Morris model, indicating that the adsorption process was chemisorption, while the Weber and Morris described the rate-controlling steps. The intraparticle diffusion model suggests that the adsorption processes were pore and surface diffusion controlled. The Langmuir isotherm model best describes the adsorption process indicating homogeneous monolayer coverage of MB molecules onto the surface of the Z-Fe3O4 NC. The maximum Langmuir adsorption capacity was 2.57 mg/g at 25°C. The maximum adsorption efficiency was 97.5%. After regeneration, the maximum adsorption efficiency achieved at a pH of 7 was 82.6%.


2014 ◽  
Vol 556-562 ◽  
pp. 282-285
Author(s):  
Li Fang Zhang ◽  
Zhao Shao ◽  
Chun Yang Jiang

In this study, Biosorption of Ni (II) ions from aqueous solution by using biomass ofAspergillusnigerwas investigated. Different parameters such as initial pH, Ni (II) ions concentration, contact time and temperature were explored. The biosorption of Ni (II) ions was highly pH dependent and the optimum pH for biosorption of Ni (II) ions was found to be 7.0. The biosorption equilibrium was established in about 30min of contact time. Ni (II) ions removal increased with increasing temperature in the studied range. Equilibrium uptake of Ni (II) ions onto biomass increased with increasing initial Ni (II) ions concentration (20-300mg/L). The Langmuir and Freundlich isotherm models were applied to experimental equilibrium data and the Langmuir model better described the equilibrium metal uptake than the Freundlich model. These results suggest that the biomass ofAspergillusnigeris a promising biosorbent for removal of nickel (II) ions from the wastewater.


2016 ◽  
Vol 2 (1) ◽  
pp. 71-80
Author(s):  
Lisa Adhani ◽  
Isalmi Aziz ◽  
Siti Nurbayti ◽  
Christie Adi Octavia

Used cooking oil can be used as raw material for biodiesel, but the levels of free fatty acids (Free Fatty Acid, FFA) is quite high. It is necessary for pretreatment in the form of the adsorption process to reduce levels of FFA. This study aims to determine the optimal conditions of adsorption process and determine the quality of biodiesel produced from adsorption processes and transesterification. Natural zeolites are used as adsorbents activated beforehand using ammonium chloride, calcined and heated to obtain H-zeolite. Furthermore, the adsorption process optimization includes the time, the adsorbent concentration, temperature and particle size. The oil that is already in the adsorption catalyst is reacted with methanol and KOH to obtain biodiesel. The optimum adsorption conditions obtained at the time of 90 minutes, the concentration of H-zeolite 12%, temperature 90 ° C, and a particle size of 0.2 mm that can lower FFA levels from 3.2% to 1.1%. Biodiesel produced meets the quality requirements of SNI 04-7182-2006 with a water content of 0.02%, a density of 857.60 kg / m3, the acid value of 0.29 mg-KOH / g, iodine number 15.71, saponification 168 , 02 and cetane index of 75.62. Compounds contained in biodiesel are methyl 9-octadecanoic (49.45%), methyl heksadekanoat (20.79%), and methyl 9,12oktaekanoat 9.12 (18.87%). Keywords: Biodiesel, used cooking oil, adsorption, transesterification, H-zeolitDOI: http://dx.doi.org/10.15408/jkv.v2i1.3107


2020 ◽  
Vol 4 (2) ◽  
pp. 75-81
Author(s):  
Nasir Abdus- Salam ◽  
Fabian Audu Ugbe ◽  
Abiola Victoria Ikudayisi- Ugbe

In this work, removal of Eosin Yellow (EY) using Natural Goethite (NGT) and Synthetic Goethite (SGT) particles was studied using batch equilibrium technique. Different parameters such as initial dye concentration, particle size (NGT only), pH, and adsorbent dose were optimized to investigate the sorbents efficiency for the dye. The experimental data were tested for fitness into five common adsorption isotherm models. The various equilibrium parameters studied were found to have remarkable influence on the adsorption processes, showing optimum removal at dye concentration (150 mg/L for EY-NGT and 200 mg/L for EY-SGT), NGT particle size (0.112mm), pH (2), and dosage (0.05g), with SGT exhibiting relatively higher adsorption efficiency. The sorption data fitted well the various isotherm models in the order; Freundlich (R2 = 0.9032) > Temkin (0.8294) > Langmuir (0.8268) > DKR (0.6431) > Flory Huggins (0.616) for EY-NGT, and Langmuir (0.9831) > Flory Huggins (0.9639) > Freundlich (0.9597) > Temkin (0.8944) > DKR (0.5993) for EY-SGT. The monolayer adsorption capacity (qm) was calculated as 1.17 and 20.80 mgg-1 for NGT and SGT respectively. Additionally, combined information obtained from the isotherm study revealed that the processes were favourable, spontaneous and proceeded by a multilayer physical adsorption on already chemisorbed layer. Conclusively, the results of this study have provided useful information on the optimum working condition and mechanism of EY uptake onto goethite surfaces.


2018 ◽  
Vol 34 (3) ◽  
pp. 1283-1296
Author(s):  
Najah Ayad Alshammari ◽  
Ehteram A. Noor ◽  
Jamilah Mohammad Alahmari

The effect of Amberlite-IR 120 H+ resin to remove some organic compounds (N-alkyl pyridinium salts) from aqueous solutions at certain conditions was investigated. The effect of resin dosage, contact time, adsorbate concentration, ionic strength and solution temperature on the adsorption efficiency was examined. The experimental data collected generally proved that the adsorption efficiency decreased as the alkyl chain increased. The thermodynamic equilibrium parameters of the adsorption processes were evaluated and showed that the adsorption process is spontaneous, disordered and exothermic. Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D.R) isotherm models were applied based on the batch method. Freundlich, Temkin and D. R gave bilinear segments model based on the adsorbate initial concentrations except that for compound III where it gave straight of one segment for Temkin adsorption isotherm. Overall, Amberlite-IR 120 H+ resin is effective in removing some N-alkyl pyridinium salts from an aqueous solution.


2018 ◽  
Vol 8 (10) ◽  
pp. 1903 ◽  
Author(s):  
Puqi Jia ◽  
Hongwei Tan ◽  
Kuiren Liu ◽  
Wei Gao

Bone char was prepared from bovine bone for the removal of methylene blue from aqueous solution. The effects of particle size, contact time, and adsorption temperature on the removal rate of methylene blue were investigated. It was found that bone char particle size had an insignificant effect. The equilibration time was found at approximately 80 min. The removal rate decreased with an increase in temperature. The intraparticle diffusion was the main rate-limiting step. The experimental data was analyzed by kinetic, isotherm, and thermodynamic equations. The results show that the pseudo-second-order kinetic model and Freundlich, Temkin, and Dubinin–Kaganer–Radushkevich isotherm models are true of the adsorption process. The spontaneous and exothermic ion-exchange adsorption process was certified by the negative values of free energy change and enthalpy change, and 13.29 kJ mol−1 of adsorption energy.


Clay Minerals ◽  
2009 ◽  
Vol 44 (1) ◽  
pp. 125-133 ◽  
Author(s):  
H. Faghihian ◽  
M. Nejati-Yazdinejad

AbstractL-cysteine (Cys) was adsorbed by bentonite (Ben) from aqueous solutions of variable concentrations and pHs. The raw materials and the adsorbed molecules (Ben-Cys) were characterized using X-ray diffraction (XRD), infrared spectroscopy (IR), thermal analysis methods (TG, DTG and DSC). The results indicated that the adsorption process depended strongly on pH, temperature and concentration of amino acid. Cysteine is specifically adsorbed on bentonite surface sites, probably through its NH3+ moiety. The pH dependence suggests that these sites may be silanolate groups (≡Si-O–). It is presumed that ion exchange interaction governs the adsorption process. The experimental data of adsorption isotherms obtained and analysed with the Langmuir model showed that this model fitted the adsorption data. Calculated thermodynamic parameters (ΔHº, ΔSº, and ΔGº) indicate that the adsorption processes were exothermic.


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