scholarly journals Photo-assisted heterogeneous Fenton-like process for treatment of PNP wastewater

2020 ◽  
Vol 10 (1) ◽  
pp. 136-145 ◽  
Author(s):  
F. C. Ban ◽  
X. T. Zheng ◽  
H. Y. Zhang
Keyword(s):  
Kinetic Equation ◽  
Ph Value ◽  
Removal Rate ◽  
Optimum Process ◽  
Process Conditions ◽  
Order Kinetic ◽  
Heterogeneous Fenton ◽  
Solution Ph ◽  
Order Kinetic Model ◽  
Fenton System

Abstract The purpose of this study was to investigate the effect of photo-assisted heterogeneous Fenton on p-nitrophenol (PNP) wastewater treatment by a homemade reactor. Supported Fe-Ce/Al2O3 was used as a catalyst and H2O2 as an oxidant to treat simulated p-nitrophenol wastewater under ultraviolet light. The effects of H2O2 dosage, catalyst dosage, initial solution pH value, reaction temperature and reaction time on the removal rate of p-nitrophenol in a photo-assisted heterogeneous Fenton system were determined. According to the relation between the concentration of each component and time, the relation curve is fitted, and then the kinetic equation is established. Finally, we obtained the optimum process conditions to achieve the PNP wastewater removal rate of 98.7%. The degradation of the photo-assisted heterogeneous Fenton method conforms to the first-order kinetic model, and the kinetic equation is . Therefore, photo-assisted heterogeneous Fenton treatment of PNP wastewater is effective and can be used in the treatment of refractory wastewater.

Comparative Study of Removal of Cadmium (II) and Chromium (III) Ions from Aqueous Solution Using Low-Cost Biosorbent

2014 ◽  
Vol 12 (1) ◽  
pp. 477-486 ◽  
Author(s):  
Abbas H. Sulaymon ◽  
Ahmed A. Mohammed ◽  
Tariq J. Al-Musawi
Keyword(s):  
Ph Value ◽  
Removal Rate ◽  
Low Cost ◽  
Order Kinetic ◽  
Cadmium Removal ◽  
Biosorption Capacity ◽  
Biosorption Process ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Batch Biosorption

Abstract This study aims to evaluate the ability of abundant low-cost garden grass to remove cadmium and chromium ions from aqueous solutions. Batch biosorption studies were carried out to examine the biosorption capacity, pH value, temperature, agitation speed, and metal ions concentration. The biosorption process revealed that the garden grass was an effective biosorbent of cadmium and chromium. The maximum chromium and cadmium removal rate was 90 and 80% at pH 4, respectively. FTIR spectroscopy analysis showed that the hydroxyl, amine, and carboxyl groups were the major groups responsible for the biosorption process. The maximum biosorption capacity was 18.19 and 19.4 mg/g for cadmium and chromium, respectively. The biosorption isotherm data fitted well the Langmuir model. Kinetic data were adequately fitted by the pseudo-second-order kinetic model.

scholarly journals Sorption of Pb(II) and Cu(II) by low-cost magnetic eggshells-Fe3O4 powder

2012 ◽  
Vol 18 (2) ◽  
pp. 221-231 ◽  
Author(s):  
Jianwei Ren ◽  
Mokgadi Bopape ◽  
Katlego Setshedi ◽  
Jacob Kitinya ◽  
Maurice Onyango
Keyword(s):  
Metal Ions ◽  
Ph Value ◽  
Low Cost ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Solution Ph ◽  
Freundlich Adsorption Isotherm ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Media Interaction

This study explored the feasibility of using magnetic eggshell-Fe3O4 powder as adsorbent for the removal of Pb(II) and Cu(II) ions from aqueous solution. The metal ionsadsorption media interaction was characterized using XRD and FTIR. The effects of contact time, initial concentrations, temperature, solution pH and reusability of the adsorption media were investigated. The metal ions adsorption was fast and the amount of metal ions adsorbed increased with an increase in temperature, suggesting an endothermic adsorption. The kinetic data showed that the adsorption process followed the pseudo-second-order kinetic model. The optimal adsorption pH value was around 5.5 at which condition the equilibrium capacity was 263.2 mg/g for Pb(II) and 250.0 for Cu(II). The adsorption equilibrium data fitted very well to the Langmuir and Freundlich adsorption isotherm models. The thermodynamics of Pb(II) and Cu(II) adsorption onto the magnetic eggshell-Fe3O4 powder indicated that the adsorption was spontaneous. The reusability study has proven that magnetic eggshell-Fe3O4 powder can be employed as a low-cost and easy to separate adsorbent.

scholarly journals Preparation of new diatomite–chitosan composite materials and their adsorption properties and mechanism of Hg(II)

2017 ◽  
Vol 4 (12) ◽  
pp. 170829 ◽  
Author(s):  
Yong Fu ◽  
Xiaoxu Xu ◽  
Yue Huang ◽  
Jianshe Hu ◽  
Qifan Chen ◽  
...  
Keyword(s):  
Adsorption Isotherm ◽  
Kinetic Model ◽  
Contact Time ◽  
Ph Value ◽  
Raw Materials ◽  
Removal Rate ◽  
Adsorption Properties ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Order Kinetic Model

A new composite absorbent with multifunctional and environmental-friendly structures was prepared using chitosan, diatomite and polyvinyl alcohol as the raw materials, and glutaraldehyde as a cross-linking agent. The structure and morphology of the composite absorbent, and its adsorption properties of Hg(II) in water were characterized with Fourier transform infrared (FT-IR) spectra, scanning electron microscope (SEM), X-ray diffraction (XRD), Brunauer Emmett Teller (BET) measurements and ultraviolet–visible (UV–Vis) spectra. The effect of the pH value and contact time on the removal rate and absorbance of Hg(II) was discussed. The adsorption kinetic model and static adsorption isotherm and regeneration of the obtained composite absorbent were investigated. The results indicated that the removal of Hg(II) on the composite absorbent followed a rapid adsorption for 50 min, and was close to the adsorption saturation after 1 h, which is in accord with the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model. When the pH value, contact time and the mass of the composite absorbent was 3, 1 h and 100 mg, respectively, the removal rate of Hg(II) on the composite absorbent reached 77%, and the maximum adsorption capacity of Hg(II) reached 195.7 mg g −1 .

scholarly journals Effective adsorption of direct Red 23 by sludge biochar-based adsorbent: adsorption kinetics, thermodynamics and mechanisms study

2021 ◽  
Author(s):  
Ruqing Jiang ◽  
Guangwei Yu ◽  
Pamphile Ndagijimana ◽  
Yu Wang ◽  
Futian You ◽  
...  
Keyword(s):  
Adsorption Kinetics ◽  
Electrostatic Interactions ◽  
Removal Rate ◽  
Order Kinetic ◽  
Solution Ph ◽  
Adsorption Mechanisms ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Solid Adsorbents ◽  
Pseudo Second Order

Abstract Using solid adsorbents, such as biochar, has been a potential practice to remove the pollutants from water bodies to render the water safer for potential usage. A potential application of sludge biochar-based adsorbent (SBA) obtained by pyrolysis with hydrothermal treatment was developed to adsorb Direct Red 23 (DR23) from wastewater. The results showed that the synthesized SBA (0.5 g/L) in the adsorption of DR23 at low concentration (<20 mg/L), the DR23 were totally removed from the aqueous solution. PH had a limited effect on the adsorption, while an increase in temperature was shown to have a large enhancing effect. The adsorption kinetics were the best fit by the pseudo-second-order kinetic model, while the equilibrium data were best fitted by the Langmuir isotherm. A maximum saturation adsorption capacity of SBA of 111.98 mg/g was achieved. SBA could then be regenerated by pyrolysis, and after three cycles, SBA still retained the good adsorption ability of DR23, a removal rate exceeding 97% was achieved. Functional groups, pores, π-π bond, and electrostatic interactions are the key to the adsorption mechanisms. The results proved that SBA would be a promising material in the removal application of dyes in printing and dyeing wastewater.

MODIFIED AMORPHOUS SiO2 FROM Zr-CONTAINING SILICA RESIDUE: A PROMISING WAY OF RECYCLING USEFUL MATERIALS AS WELL AS REMOVING Cr(VI) FROM WATER

2021 ◽  
pp. 2150022
Author(s):  
YU LIANG ◽  
WANTING CHEN ◽  
HAN ZHANG ◽  
JIMO WANG ◽  
HAO DING ◽  
...  
Keyword(s):  
Ph Value ◽  
Waste Water Treatment ◽  
Order Kinetic ◽  
Solution Ph ◽  
Amorphous Sio2 ◽  
Adsorption Temperature ◽  
Effective Option ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
The Impact

The amorphous SiO2, which is purified from Zr-containing silica residue, was modified by CTAB before the adsorption of Cr(VI). The impact of different variables, such as solution pH value, adsorption time, adsorption temperature, and adsorbent dosage were investigated on the Cr(VI) removal from solution. The results show that the optimal pH value for Cr(VI) adsorption is 3. And 60 min is needed for the adsorption with 10 g/L of modified amorphous SiO2 at [Formula: see text]C. The acquired adsorption isotherm and the adsorption process can be interpreted by Langmuir model and pseudo-second-order kinetic model, respectively. This paper provides an effective option for waste water treatment as well as a way of recycling useful materials from the discarded Zr-containing silica residue.

Orthogonal Study on the Degradation of Aniline Process Parameters by Ultrasonic

2014 ◽  
Vol 488-489 ◽  
pp. 70-73
Author(s):  
Yong Guang Bi ◽  
Min Xia Huang
Keyword(s):  
Process Parameters ◽  
Ph Value ◽  
New Technology ◽  
Optimum Process ◽  
Process Conditions ◽  
Ultrasonic Power ◽  
Solution Ph ◽  
Ultrasonic Time ◽  
Ultrasonic Degradation ◽  
The Impact

Objective: To optimize the ultrasonic degradation of aniline wastewater process parameters. Methods: ultrasonic power, ultrasonic time, ultrasonic temperature, pH value, etc. 4 orthogonal factors and determine the optimum process conditions. Results: In the ultrasonic power 320W, ultrasonic time was 60min, ultrasonic temperature is 30 °C, pH value of 4 under the action of ultrasound sonication best, under optimum conditions, aniline degradation rate of 90.08%, and the various factors the impact of the size order of ultrasonic temperature> ultrasonic time> ultrasonic power> solution pH. Conclusion: Ultrasonic degradation of organic matter, is easy to operate, efficient, non-polluting or less polluting characteristics, is a better degradation of aniline wastewater new technology.

Heterogeneous Fenton Catalytic Removal of Organic Pollutant in Aqueous Solution by using Coal Gangue as a Catalyst

2019 ◽  
Vol 12 (4) ◽  
pp. 312-325
Author(s):  
Jiwei Zhang ◽  
Jingjing Xu ◽  
Shuaixia Liu ◽  
Baoxiang Gu ◽  
Feng Chen ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
Hydroxyl Radical ◽  
Removal Rate ◽  
Organic Pollutant ◽  
Coal Gangue ◽  
Ion Leakage ◽  
Heterogeneous Fenton ◽  
Solution Ph ◽  
X Ray

Background: Coal gangue was used as a catalyst in heterogeneous Fenton process for the degradation of azo dye and phenol. The influencing factors, such as solution pH gangue concentration and hydrogen peroxide dosage were investigated, and the reaction mechanism between coal gangue and hydrogen peroxide was also discussed. Methods: Experimental results showed that coal gangue has the ability to activate hydrogen peroxide to degrade environmental pollutants in aqueous solution. Under optimal conditions, after 60 minutes of treatment, more than 90.57% of reactive red dye was removed, and the removal efficiency of Chemical Oxygen Demand (COD) up to 72.83%. Results: Both hydroxyl radical and superoxide radical anion participated in the degradation of organic pollutant but hydroxyl radical predominated. Stability tests for coal gangue were also carried out via the continuous degradation experiment and ion leakage analysis. After five times continuous degradation, dye removal rate decreased slightly and the leached Fe was still at very low level (2.24-3.02 mg L-1). The results of Scanning Electron Microscope (SEM), energy dispersive X-Ray Spectrometer (EDS) and X-Ray Powder Diffraction (XRD) indicated that coal gangue catalyst is stable after five times continuous reuse. Conclusion: The progress in this research suggested that coal gangue is a potential nature catalyst for the efficient degradation of organic pollutant in water and wastewater via the Fenton reaction.

Adsorption Characteristics of Phenol in Aqueous Solution by Pinus massoniana Biochar

2013 ◽  
Vol 295-298 ◽  
pp. 1154-1160 ◽  
Author(s):  
Guo Zhi Deng ◽  
Xue Yuan Wang ◽  
Xian Yang Shi ◽  
Qian Qian Hong
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Pinus Massoniana ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorbent Dosage ◽  
Salt Ions ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The objective of this paper is to investigate the feasibility of phenol adsorption from aqueous solution by Pinus massoniana biochar. Adsorption conditions, including contact time, initial phenol concentration, adsorbent dosage, strength of salt ions and pH, have been investigated by batch experiments. Equilibrium can be reached in 24 h for phenol from 50 to 250 mg• L-1. The optimum pH value for this kind of biochar is 5.0. The amount of phenol adsorbed per unit decreases with the increase in adsorbent dosage. The existence of salt ions makes negligible influence on the equilibrium adsorption capacity. The experimental data is analyzed by the Freundlich and Langmuir isotherm models. Equilibrium data fits well to the Freundlich model. Adsorption kinetics models are deduced and the pseudo-second-order kinetic model provides a good correlation for the adsorbent process. The results show that the Pinus massoniana biochar can be utilized as an effective adsorption material for the removal of phenol from aqueous solution.

scholarly journals The sorption of inorganic arsenic on modified sepiolite: Effect of hydrated iron(III)-oxide

2014 ◽  
Vol 79 (7) ◽  
pp. 815-828 ◽  
Author(s):  
Nikola Ilic ◽  
Slavica Lazarevic ◽  
Vladana Rajakovic-Ognjanovic ◽  
Ljubinka Rajakovic ◽  
Djordje Janackovic ◽  
...  
Keyword(s):  
Sorption Capacity ◽  
Arsenic Removal ◽  
Ph Value ◽  
Inorganic Arsenic ◽  
Arsenic Species ◽  
Deionized Water ◽  
Order Kinetic ◽  
Initial Ph ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The sorption of inorganic arsenic species, As(III) and As(V), from water by sepiolite modified with hydrated iron(III) oxide was investigated at 25 ?C through batch studies. The influence of the initial pH value, the initial As concentrations, the contact time and types of water on the sorption capacity was investigated. Two types of water were used, deionized and groundwater. The maximal sorption capacity for As(III) from deionized water was observed at initial and final pH value 7.0, while the bonding of As(V) was observed to be almost pH independent for pH value in the range from 2.0 to 7.0, and the significant decrease in the sorption capacity was observed at pH values above 7.0. The sorption capacity at initial pH 7.0 was about 10 mg g?1 for As(III) and 4.2 mg g?1 for As(V) in deionized water. The capacity in groundwater was decreased by 40 % for As(III) and by 20 % for As(V). The Langmuir model and pseudo-second order kinetic model revealed good agreement with the experimental results. The results show that Fe(III)-modified sepiolite exhibits significant affinity for arsenic removal and it has a potential for the application in water purification processes.

scholarly journals Lignocellulose@ Activated Clay Nanocomposite with Hierarchical Nanostructure Enhancing the Removal of Aqueous Zn(II)

Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1710 ◽  
Author(s):  
Xiaotao Zhang ◽  
Yinan Hao ◽  
Zhangjing Chen ◽  
Yuhong An ◽  
Wanqi Zhang ◽  
...  
Keyword(s):  
Ph Value ◽  
Removal Rate ◽  
Weight Ratio ◽  
Order Kinetic ◽  
Adsorption Parameters ◽  
Hierarchical Nanostructure ◽  
Desorption Temperature ◽  
Desorption Time ◽  
Adsorption Temperature ◽  
Hcl Concentration

A lignocellulose@ activated clay (Ln@AC) nanocomposite with a hierarchical nanostructure was successfully synthesized by the chemical intercalation reaction and applied in the removal of Zn(II) from an aqueous solution. Ln@AC was characterized by N2 adsorption/desorption isotherms and X-Ray Diffraction (XRD), scanning Electron Microscope (SEM), transmission Electron Microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis, and the results indicate that an intercalated–exfoliated hierarchical nanostructure was formed. The effects of different adsorption parameters on the Zn(II) removal rate (weight ratio of Ln to AC, Ln@AC dosage, initial Zn(II) concentration, pH value, adsorption temperature, and time) were investigated in detail. The equilibrium adsorption capacity reached 315.9 mg/g under optimal conditions (i.e., the weight ratio of Ln to AC of 3:1, Ln@AC dosage of 1 g/L, initial Zn(II) concentration of 600 mg/L, pH value of 6.8, adsorption temperature of 65 °C, and adsorption time of 50 min). The adsorption process was described by the pseudo-second-order kinetic model, Langmuir isotherm model, and the Elovich model. Moreover, Zn(II) could be easily eluted by HCl, and the effects of HCl concentration, desorption temperature, and ultrasonic desorption time on desorbed amount were tested. Desorption studies revealed that with an HCl concentration of 0.25 mol/L, desorption temperature of 70 °C, and ultrasonic desorption time of 20 min, the maximum desorption capacity and efficiency were achieved at 202.5 mg/g and 64.10%, respectively. Regeneration experimental results indicated that the Ln@AC exhibited a certain recyclable regeneration performance. Due to such outstanding features, the novel Ln@AC nanocomposite proved to have great adsorption potential for Zn(II) removal from wastewater, and exhibited an extremely significant amount of adsorbed Zn(II) when compared to conventional adsorbents.

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