scholarly journals Synthesis of walnut shell modified with titanium dioxide and zinc oxide nanoparticles for efficient removal of humic acid from aqueous solutions

2016 ◽  
Vol 14 (6) ◽  
pp. 989-997 ◽  
Author(s):  
Ali Naghizadeh ◽  
Habibeh Shahabi ◽  
Fatemeh Ghasemi ◽  
Ahmad Zarei
Keyword(s):  
Zinc Oxide ◽  
Titanium Dioxide ◽  
Humic Acid ◽  
Aqueous Solutions ◽  
Contact Time ◽  
Walnut Shell ◽  
Maximum Adsorption Capacity ◽  
High Adsorption ◽  
Efficient Removal ◽  
Batch Condition

The main aim of this research was to study the efficiency of modified walnut shell with titanium dioxide (TiO2) and zinc oxide (ZnO) in the adsorption of humic acid from aqueous solutions. This experimental study was carried out in a batch condition to determine the effects of factors such as contact time, pH, humic acid concentration, dose of adsorbents (raw walnut shell, modified walnut shell with TiO2 and ZnO) on the removal efficiency of humic acid. pHzpc of raw walnut shell, walnut shell modified with TiO2 and walnut shell modified with ZnO were 7.6, 7.5, and 8, respectively. The maximum adsorption capacity of humic acid at concentration of 30 mg/L, contact time of 30 min at pH = 3 in an adsorbent dose of 0.02 g of walnut shell and ZnO and TiO2 modified walnut shell were found to be 35.2, 37.9, and 40.2 mg/g, respectively. The results showed that the studied adsorbents tended to fit with the Langmuir model. Walnut shell, due to its availability, cost-effectiveness, and also its high adsorption efficiency, can be proposed as a promising natural adsorbent in the removal of humic acid from aqueous solutions.

scholarly journals Behaviour of titanium dioxide and zinc oxide nanoparticles in the presence of wastewater-derived organic matter and implications for algal toxicity

2015 ◽  
Vol 2 (1) ◽  
pp. 86-93 ◽  
Author(s):  
Peta A. Neale ◽  
Åsa K. Jämting ◽  
Elissa O'Malley ◽  
Jan Herrmann ◽  
Beate I. Escher
Keyword(s):  
Zinc Oxide ◽  
Titanium Dioxide ◽  
Organic Matter ◽  
Humic Acid ◽  
Zinc Oxide Nanoparticles ◽  
Wastewater Effluent ◽  
Oxide Nanoparticles ◽  
Zno Nanomaterials ◽  
Algal Toxicity

This study compared the behaviour and effect of TiO2 and ZnO nanomaterials in wastewater effluent, humic acid and test media.

Application of Chitosan Film for the Removal of Triclosan from Aqueous Solutions by Adsorption

2016 ◽  
Vol 675-676 ◽  
pp. 455-458
Author(s):  
Peeyanan Noirod ◽  
Jittapat Lamangthong ◽  
Padarat Ninjiaranai
Keyword(s):  
Aqueous Solutions ◽  
Contact Time ◽  
Chitosan Film ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Acidic Ph ◽  
Adsorption Efficiency ◽  
Freundlich Isotherms ◽  
Langmuir And Freundlich Isotherms ◽  
Equilibrium Data

The aim of this work was to study the adsorption efficiency of chitosan as an adsorbent for triclosan, commercially known as Irgasan, in aqueous solutions. The effects of contact time, pH and temperature were investigated using a batch adsorption technique. Langmuir and Freundlich isotherms were used to analyze the equilibrium data at different absorption conditions. The results showed that the maximum adsorption capacity for chitosan was found in the acidic pH 3 and at a temperature of 65 oC. These results suggested that chitosan can be used as an adsorbent for removal of triclosan from aqueous solutions.

Adsorption of methyl violet from aqueous solution using brown algae Padina sanctae-crucis

2018 ◽  
Vol 43 (6) ◽  
pp. 623-631 ◽  
Author(s):  
Reza Mahini ◽  
Hossein Esmaeili ◽  
Rauf Foroutan
Keyword(s):  
Aqueous Solutions ◽  
Brown Algae ◽  
Contact Time ◽  
Methyl Violet ◽  
Kinetic Studies ◽  
Maximum Adsorption Capacity ◽  
Order Model ◽  
Equilibrium Study ◽  
Freundlich Isotherms ◽  
Pseudo Second Order

Abstract Objective The presence of dyes in the water is toxic and harmful to human body so, it must be removed from the water. In the present study, the removal of methyl violet (MV) from aqueous solutions using brown algae “Padina sanctae-crucis” was investigated. Materials and methods The rate of adsorption was investigated under various parameters such as contact time (5–200), pH (2–11), dye concentration (10–60 mg/L), amount of adsorbent (0.25–5 g/L) and temperature (25–45°C). Results The maximum adsorption was achieved in 10 mg/L, pH=8 and adsorbent dose 2 g/L and 80 min contact time for removal of MV from aqueous solutions. Kinetic studies showed that the pseudo second-order model describes adsorbent kinetic behavior better. Besides, experimental data have been modeled using Langmuir and Freundlich isotherms and the results showed that both models are proper to describe adsorption isotherm behavior. In addition, the equilibrium study shows that the adsorption was physical and favorable. Moreover, a thermodynamic study revealed that the adsorption process is exothermic and spontaneously in nature. Furthermore, Maximum adsorption capacity using adsorbent was 10.02 mg/g. Conclusions It could be concluded that the P. sanctae-crucis biomass is a good adsorbent for removing MV dyes from aqueous solutions.

scholarly journals Gum Arabic-Magnetite Nanocomposite as an Eco-Friendly Adsorbent for Removal of Lead(II) Ions from Aqueous Solutions: Equilibrium, Kinetic and Thermodynamic Studies

Separations ◽  
2021 ◽  
Vol 8 (11) ◽  
pp. 224
Author(s):  
Ismat H. Ali ◽  
Mutasem Z. Bani-Fwaz ◽  
Adel A. El-Zahhar ◽  
Riadh Marzouki ◽  
Mosbah Jemmali ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solutions ◽  
Contact Time ◽  
Gum Arabic ◽  
Ion Concentration ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Transmission Electron ◽  
Order Kinetic Model ◽  
Langmuir Isotherm Model

In this study, a gum Arabic-magnetite nanocomposite (GA/MNPs) was synthesized using the solution method. The prepared nanocomposite was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). The prepared composite was evaluated for the adsorption of lead(II) ions from aqueous solutions. The controlling factors such as pH, contact time, adsorbent dose, initial ion concentration, and temperature were investigated. The optimum adsorption conditions were found to be 0.3 g/50 mL, pH = 6.00, and contact time of 30 min. The experimental data well fitted the pseudo-second-order kinetic model and the Langmuir isotherm model. The maximum adsorption capacity was determined as 50.5 mg/g. Thermodynamic parameters were calculated postulating an endothermic and spontaneous process and a physio-sorption pathway.

scholarly journals Al (III) removal from wastewaters by natural clay and coconut shell

2019 ◽  
Keyword(s):  
Aqueous Solutions ◽  
Contact Time ◽  
Acid Treatment ◽  
Adsorption Process ◽  
Coconut Shell ◽  
Maximum Adsorption Capacity ◽  
Agitation Rate ◽  
Batch Experiments ◽  
Natural Clay ◽  
Initial Ph

<p>This paper describes the adsorption of Al3+ ions from aqueous solutions, by natural clay (from Sakarya's Yenigün district) and coconut shell modified by means of acid treatment. Batch experiments were carried out to determine the effect of various factors such as initial pH (4-9), temperature (20, 40, 70 oC), initial concentration (10 to 200 mg L-1) and contact time (1-120 minute) on the adsorption process. The adsorption experiments were performed at a temperature of 20 ±2 oC), at 200 rpm agitation rate, with an adsorbent level of 1 g L-1, produced 98.95% (at pH 6) and 92.83% (at pH 7) maximum Al3+ removal efficiency for clay and coconut shell based adsorbents respectively. Furthermore, the process was found to be exothermic for clay and endothermic for coconut. XRF and XRD analyses of the clay variety used in adsorption analyses revealed it to be saponite clay, within the larger group of smectite clay minerals. The application of Langmuir revealed maximum adsorption capacity of 149.25 mg g-1 for natural clay adsorbent (NCA), and 120.482 mg g-1 for coconut shell adsorbent (CSA). Moreover, adsorption kinetics were found to be consistent with the second order kinetics (R2 &gt; 0.95). The result shows that, natural clay and coconut shell adsorbents are effective adsorbents to remove Al3+ from aqueous solutions with good adsorption rate (&gt;92.8%).</p>

scholarly journals Adsorption of Some Alephatic Dicarboxylic Acids on Zinc Oxide: A kinetic and Thermodynamic Study

2019 ◽  
Vol 16 (4) ◽  
pp. 0892
Author(s):  
Saddam M. Al-Mahmoud
Keyword(s):  
Zinc Oxide ◽  
Aqueous Solutions ◽  
Contact Time ◽  
Adsorption Process ◽  
Dicarboxylic Acids ◽  
Second Order ◽  
Oxide Surface ◽  
Adsorption Efficiency ◽  
Good Ability ◽  
Pseudo Second Order

The adsorption of Malonic acid, Succinic acid, Adipic acid, and Azelaic acid from their aqueous solutions on zinc oxide surface were investigated. The adsorption efficiency was investigated using various factors such as adsorbent amount, contact time, initial concentration, and temperature. Optimum conditions for acids removal from its aqueous solutions were found to be adsorbent dose (0.2 g), equilibrium contact time (40 minutes), initial acids concentration (0.005 M). Variation of temperature as a function of adsorption efficiency showed that increasing the temperature would result in decreasing the adsorption ability. Kinetic modeling by applying the pseudo-second order model can provide a better fit of the data with a greater correlation coefficient, which indicates that the adsorption process follow the pseudo-second order kinetics. The negative values of Gibbs free energy and the enthalpy change confirm the spontaneous and exothermic nature of the adsorption process. A good ability of zinc oxide to remove aliphatic dicarboxylic acids from its aqueous solutions has been found, and the chain length of the acids has no significant effect on its adsorption.

MgO Functionalized Magnetic Activated Carbon Material for Efficient Removal of Malachite Green from Aqueous Solutions

NANO ◽  
2021 ◽  
pp. 2150054
Author(s):  
Zongli Ren ◽  
Zhao Yang ◽  
Zhongwei Zhao ◽  
Xuan Yang
Keyword(s):  
Activated Carbon ◽  
Aqueous Solutions ◽  
Malachite Green ◽  
Contact Time ◽  
Negative Impact ◽  
Synthesis Method ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Magnetic Activated Carbon ◽  
The Cost

Malachite green (MG) pollution has a negative impact on human health. At present, the method of removing it is inconvenient to operate and the cost is high, which has aroused widespread concern. In this study, MgO functionalized magnetic activated carbon (MgO-mAC) prepared by the sol–gel method was used to remove MG in water. The physical and chemical properties of MgO-mAC were tested by SEM, TEM, FTIR, XRD, BET and VSM. The effects of adsorbent dosage, solution pH, contact time, initial MG concentration and temperature on adsorption were studied by batch experiments. The adsorption kinetics data is well described by a pseudo-second-order model. The equilibrium data fits the Langmuir isotherm well. When the pH is 8 and the contact time is 360[Formula: see text]min, the maximum adsorption capacity of MG is 3809[Formula: see text]mg[Formula: see text]g[Formula: see text]. In thermodynamic studies, [Formula: see text], [Formula: see text], [Formula: see text], MG adsorption is an endothermic and spontaneous adsorption process. The current synthesis method is simple in operation and cheap in raw materials, which can greatly reduce the cost of synthesis. Hence, the MgO-mAC material will be an effective adsorbent for removing MG from aqueous solutions.

scholarly journals A Comparative Efficiency Study of Two Adsorbent Materials to Remove Eosin Y Dye from Aqueous Solutions

2018 ◽  
Vol 15 (4) ◽  
pp. 387-391
Author(s):  
Baghdad Science Journal
Keyword(s):  
Aqueous Solutions ◽  
Contact Time ◽  
Fine Particles ◽  
Ph Value ◽  
Inverse Correlation ◽  
Walnut Shell ◽  
Eosin Y ◽  
Comparative Efficiency ◽  
Fourth Experiment ◽  
Adsorbent Materials

This study was done to find a cheap, available and ecofriendly materials that can remove eosin y dye from aqueous solutions by adsorption in this study, two adsorbent materials were used, the shells of fresh water clam (Cabicula fluminea) and walnut shells. To make a comparison between the two adsorbents, five experiments were conducted. First, the effects of the contact time, here the nut shell removed the dye quickly, while the C. flumina need more contact time to remove the dye. Second, the effects of adsorbent weight were examined. The nut shell was very promising and for all used adsorbent weight, the R% ranged from 94.87 to 99.29. However C. fluminea was less effective in removing the dye with R% ranged from 47.59 to 55.39. The third experiment was initial dye concentration. The C. fluminea showed very low ability to remove eosin y , while the nut shell was more effective in removing the dye with R% up to 97.36 and an inverse correlation between the increase of initial dye concentration and R%. The fourth experiment was the effect of pH value of the solution and the adsorbent particles size. The results show that fine particles were more effective than granular particles. Throughout the whole study, the walnut shell was very promising in removing the dye, while the C. fluminea shell was much less effective than the walnut shell.

Removal of Cr(VI) from Aqueous Solutions Using Clay from Calumbi Geological Formation, N. Sra. Socorro, SE State, Brazil

2018 ◽  
Vol 912 ◽  
pp. 1-6 ◽  
Author(s):  
J.C.T. Rezende ◽  
V.H.S. Ramos ◽  
H.A. Oliveira ◽  
Rosane Maria Pessoa Betânio Oliveira ◽  
E. Jesus
Keyword(s):  
Aqueous Solutions ◽  
Contact Time ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Initial Ph ◽  
Geological Formation ◽  
Langmuir Isotherm Model

Conventional processes for heavy metal removal are costly. Natural and modified clay with quaternary ammonium salt were used as adsorbent for the removal of Cr (VI) from aqueous solutions. Clays were characterized using Fourier transform infrared spectroscopy FTIR, thermal analysis (TG/DTA) and X-ray diffraction (XRD). Cr (VI) determination was conducted by ultraviolet-visible spectrophotometry, using complexation with 1,5-diphenylcarbazide. Absorbance was measured at the wavelength of 540 nm. The experiments were conducted at 25 ± 1 °C; initial Cr (VI) concentration of 4 to 25 mg L-1; initial pH of 2, agitation of 150 rpm; contact time of 120 minutes and clay mass of 0.1 g. Natural and modified clays exhibited a maximum adsorption capacity of 2.548 mg g-1 and 17.24 mg g-1, respectively, in accordance with the Langmuir isotherm model. X-ray diffraction analysis of clay indicated that the sample consists mainly of kaolinite and montmorillonite.

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