scholarly journals Kinetic Study of the Adsorption of Polyphenols from Olive Mill Wastewater onto Natural Clay: Ghassoul

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Safae Allaoui ◽  
Mohammed Naciri Bennani ◽  
Hamid Ziyat ◽  
Omar Qabaqous ◽  
Najib Tijani ◽  
...  

The aim of this study is based on natural clay as an adsorbent in the elimination of polyphenols from olive mill wastewater (OMW). This clay was analyzed using XRD, SEM/EDX, FTIR, surface area measurement (BET method), thermal analysis (TGA/DTA), and X-ray fluorescence (XRF) and then used in adsorption experiments. The results reveal that the best quantity of adsorption of polyphenols is 161 mg/g at the temperature of 25°C, but they decrease at 35°C and 45°C. A great agreement with pseudo-second-order and Freundlich model is represented by kinetic and isotherms models, and several parameters such as ΔG0, ΔS0, and ΔH0 were determined using the thermodynamic function relationship.

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 898
Author(s):  
Ximena Jaramillo-Fierro ◽  
Silvia González ◽  
Fernando Montesdeoca-Mendoza ◽  
Francesc Medina

Adsorption is an effective method of removing harmful pollutants from air and water. In the present study, zeolites prepared by sol-gel method from two Ecuadorian clays were combined with precursor clays and the ZnTiO3/TiO2 semiconductor for adsorbing methylene blue (MB) as a water contaminant. The synthesized compounds were characterized using powder X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive X-ray, and surface area measurement. These compounds were combined to form cylindrical extrudates of 0.2 cm (diameter) and 1.0 cm (length). The adsorption characteristics of the composites were measured using batch sorption studies as a function of pH, initial concentration, and contact time. The pseudo-second-order model and the Langmuir isotherm model were better suited to the adsorption process. The equilibrium state was achieved around 180 min of adsorption, and a pH of 7 was established as the optimal operating condition. The maximum adsorption values of the dye were obtained with the composites derived from G-Clay, whose average adsorption capacity was 46.36 mg g−1, in contrast with composites derived from R-Clay, whose average adsorption value was 36.24 mg g−1. The results reflect that synthesized composites could be used potentially for the removal of cationic dye from wastewater.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohamed S. Yahia ◽  
Ahmed S. Elzaref ◽  
Magdy B. Awad ◽  
Ahmed M. Tony ◽  
Ahmed S. Elfeky

Abstract Commercial Granulated Active Carbon (GAC) has been modified using 10 Gy dose Gamma irradiation (GAC10 Gy) for increasing its ability of air purification. Both, the raw and treated samples were applied for removing Chlorpyrifos pesticide (CPF) from ambient midair. Physicochemical properties of the two materials were characterized by Fourier Transform Infrared (FT-IR) and Raman spectroscopy. The phase formation and microstructure were monitored using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), supported with Energy-Dispersive X-ray (EDX). The Surface area measurement was detected using BET particle size prosometry. Obtained outcomes showed that, the maximum adsorption capacity, given by Langmuir equations, was greatly increased from 172.712 to 272.480 mg/g for GAC and GAC10 Gy, respectively, with high selectivity. The overall removal efficiency of GAC10 Gy was notably comparable to that of the original GAC-sorbent. The present study indicated that, gamma irradiation could be a promising technique for treating GAC and turned it more active in eliminating the pesticides pollutants from surrounding air. The data of equilibrium has been analyzed by Langmuir and Freundlich models, that were considerably better suited for the investigated materials than other models. The process kinetics of CPF adsorbed onto both tested carbon versions were found to obey the pseudo first order at all concentrations with an exception at 70 mg/l using GAC, where, the spontaneous exothermic adsorption of Chlorpyrifos is a strong function for the pseudo-first order (PFO) and pseudo second order (PSO) kinetics.


Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6636
Author(s):  
Muna Abu-Dalo ◽  
Jehad Abdelnabi ◽  
Abeer Al Bawab

Olive oil production generates solid and liquid wastes that cause various environmental problems due to their high phenols and polyphenols load. Although many treatment methods were investigated to manage these wastes, more research is still needed to identify simple and cost-effective approaches. In this study, activated carbon (AC) was prepared from olive cake waste and functionalized with Cu/Cu2O/CuO for efficient and selective removal of phenolic content from olive mill wastewater (OMW). AC media were characterized by scanning electron/dispersive X-ray spectroscopy (SEM-EDS), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrometry, and Brunauer–Emmett–Teller (BET) surface area analysis. The optimum adsorption parameters were investigated, and the adsorption isotherms, thermodynamics, and kinetics were determined. The adsorption of phenols onto copper oxide AC was best described by the Langmuir adsorption with maximum adsorption capacity of 13.9, 12.7, and 9.9 mg/g at 311, 302, and 293 K, respectively. The adsorption reaction was found to be spontaneous and endothermic where ∆H° and ∆G° were found to be 30.104 kJ/mol and −1.765, −2.839, and −3.723 (kJ/mol) at 311, 302, and 293 K, respectively. In addition, the kinetics data were perfectly fit by the pseudo-second-order model. The activated product derived from recyclable olive cake and enriched with inorganic functionality can offer a cost-effective treatment solution for OMW; thus, reducing both the liquid and solid waste generated from the olive mill industry.


2020 ◽  
Vol 81 (10) ◽  
pp. 2270-2280
Author(s):  
Yonggang Xu ◽  
Tianxia Bai ◽  
Yubo Yan ◽  
Yunfeng Zhao ◽  
Ling Yuan ◽  
...  

Abstract It is of great significance to remove Cr(VI) from water as a result of its high toxicity. Biochar from corn straw was modified by different acids (HNO3, H2SO4 and H3PO4) to remove Cr(VI) from aqueous solution. To estimate the removal mechanisms of Cr(VI) by the acid-modified biochars, batch experiments were performed in the light of contact time, Cr(VI) concentration, and pH, and the characteristics of acid-modified biochars before and after Cr(VI) adsorption were investigated by Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS). The adsorption kinetics of Cr(VI) by acid-modified biochars were consistent with the pseudo-second-order model, and the adsorption isotherm obeyed the Freundlich model. Furthermore, the acid- modified biochars could supply more oxygen-containing functional groups (-COOH and -OH) as electron donor (e−) and hydrogen ion (H+) to enhance the reduction of Cr(VI) to Cr(III), resulting in enhanced removal of Cr(VI). HNO3-modified biochar exhibited the highest removal efficiency of Cr(VI). In general, the acid modifition of biochar was an effective method to increase the removal of Cr(VI).


Author(s):  
Reda Elkacmi ◽  
Noureddine Kamil ◽  
Mounir Bennajah

Treatment of olive mill wastewater (OMW) by electrocoagulation (EC) was investigated in a stirred tank reactor (STR), the effect of different influential parameters, namely, contact time, current density and pH was determined. Over 72 % of COD, 93 % of polyphenols and 95 % of color intensity were removed efficiently at pH of 5.2, current density of 58.33 mA/cm2 and a residence time of 45 min. A kinetic study of these three parameters was carried out and both COD and dark color removal obey the first-order law model. On the other hand, the polyphenols reduction, fits the pseudo second-order model with current- dependent parameters. A variable order kinetic (VOK) model derived from the Langmuir-Freundlish equation was proposed to determine the kinetics of pollutant removal reactions with EC. Results showed that the model equations strongly fit the experimental concentrations of the three pollutants.


2019 ◽  
Vol 4 (4) ◽  
pp. 101
Author(s):  
Neza Rahayu Palapa ◽  
Bakri Rio Rahayu ◽  
Tarmizi Taher ◽  
Aldes Lesbani ◽  
Risfidian Mohadi

Zn/Al and Zn/Fe layered double hydroxides has successfully synthesized by co-precipitation methods with molar ration 3:1. The samples were characterized using X-Ray Diffraction, Fourier Transform Infrared Spectroscopy and Surface Area using BET method. In this study, Zn/Al and Zn/Fe layered double hydroxides were used to remove direct yellow dye in aqueous solution. The experiments were carried out time variations with the aim of observing the kinetic studies. The results showed that the adsorption of direct yellow onto Zn/Al and Zn/Fe layered double hydroxides based on co-efficient correlation kinetic models more fit using pseudo-second-order than pseudo-first-order.


Clay Minerals ◽  
2015 ◽  
Vol 50 (4) ◽  
pp. 485-496 ◽  
Author(s):  
I. Hamadneh ◽  
R. Abu-Zurayk ◽  
B. Abu-Irmaileh ◽  
A. Bozeya ◽  
A. H. Al-Dujaili

AbstractA comparative study using bentonite (BT), hexadecyltrimethylammonium-modified bentonite (BT-HDTMA) and phenyl fatty hydroxamic acid-modified bentonite (BT-PFHA) as adsorbents for the removal of Pb(II) has been proposed. These adsorbents were characterized by X-ray diffraction, X-ray fluorescence, Fourier-transform infrared spectroscopy and surface area measurement. Cation exchange capacity was also determined in this study. The adsorbent capabilities for Pb(II) from aqueous solution were investigated, and the optimal experimental conditions including adsorption time, adsorbent dosage, the initial concentration of Pb(II), pH and temperature that might influence the adsorption performance were also investigated. The experimental equilibrium adsorption data were tested by four widely used two-parameter equations, the Langmuir, Freundlich, Dubinin- Radushkevich (D-R) and Temkin isotherms. The monolayer adsorption capacities of BT, BT-HDTMA and BT-PFHA for Pb(II) were 149.3, 227.3 and 256.4 mg/g, respectively. The experimental kinetic data were analysed by pseudo-first order, pseudo-second order and intraparticle diffusion kinetics models. The experimental data fitted very well with the pseudo-second order kinetic model. Determination of the thermodynamic parameters, ΔG, ΔH and ΔS showed the adsorption to be feasible, spontaneous and exothermic.


2011 ◽  
Vol 356-360 ◽  
pp. 529-532 ◽  
Author(s):  
Yan Wang ◽  
Liu Yang ◽  
Wei Ping Liao ◽  
Fei Wang

Two catalysts, MnOx and ceria modified MnOx were prepared by deposition-precipitation method and used for low-temperature selective catalytic reduction (SCR) with NH3in the presence of SO2. The catalysts were characterized by X-ray diffraction (XRD), surface area measurement (BET) and thermal gravimetry analysis(TG). The deactivation of MnOx and MnOx-CeO2by SO2was observed during SCR process. It was found that the resistance to SO2could be greatly enhanced for Ce modified MnOx. It was because that the formation of Mn(SO4)x was prevented and the depositions of (NH4)2SO4and NH4HSO4were significantly inhibited with the doping of ceria.


2017 ◽  
Vol 6 (3) ◽  
pp. 207
Author(s):  
Y.H. Taufiq-Yap ◽  
A. Raslan ◽  
R. Irmawati

<p>Vanadyl pyrophosphate (VO)<sub>2</sub>P<sub>2</sub>O<sub>7</sub> catalysts synthesized via VOPO<sub>4</sub>·2H<sub>2</sub>O were investigated by using BET surface area measurement, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Temperature-Programmed Techniques (TPD and TPRS). H<sub>3</sub>PO<sub>4</sub> and H<sub>4</sub>P<sub>2</sub>O<sub>7</sub> were used as the phosphorus source. Only pyrophosphate phase was observed for both final catalysts after 75 hours of calcination in a reaction flow of <em>n</em>-butane/air mixture (0.75% <em>n</em>-butane/air). However, catalyst derived from H<sub>4</sub>P<sub>2</sub>O<sub>7</sub> based preparation (denoted VPD<sub>pyro</sub>) exhibit better crystallinity and slightly higher BET surface area compared to the H<sub>3</sub>PO<sub>4</sub> based preparation (denoted VPD<sub>ortho</sub>). The nature of the oxidants for both catalysts was investigated by O<sub>2</sub>-TPD. For VPD<sub>pyro</sub>, TPD showed an oxygen peak maximum at 986 K and a shoulder at 1003 K, whereas for VPD<sub>ortho</sub>, the oxygen was desorbed as two peaks maxima at 966 and 994 K. The total amount of oxygen desorbed thermally from VPD<sub>pyro</sub> (3.60×10<sup>20</sup> atom×g<sup>-1</sup>) is higher than that obtained for VPD<sub>ortho</sub> (3.07×10<sup>20</sup> atom×g<sup>-1</sup>). VPD<sub>pyro</sub> displayed a slightly improved activity and selectivity for <em>n</em>-butane oxidation. A proper amount of V<sup>5+</sup> species may have an effect on the enhancement of the catalytic activity.</p>


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