scholarly journals Adsorption of hexavalent chromium by polyacrylonitrile-based porous carbon from aqueous solution

2018 ◽  
Vol 5 (1) ◽  
pp. 171662 ◽  
Author(s):  
Bin Feng ◽  
Wenzhong Shen ◽  
Liyi Shi ◽  
Shijie Qu
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Porous Carbon ◽  
Photoelectron Spectroscopy ◽  
Ph Value ◽  
Functional Materials ◽  
High Specific Surface Area ◽  
Maximum Adsorption Capacity ◽  
Elementary Analysis ◽  
Initial Adsorption

Owing to the unique microporous structure and high specific surface area, porous carbon could act as a good carrier for functional materials. In this paper, polyacrylonitrile (PAN)-based porous carbon materials (PPC-0.6-600, PPC-0.8-600, PPC-0.6-800 and PPC-0.8-800) were prepared by heating KOH at 600°C and 800 o C for the removal of Cr(VI) from aqueous solution. The adsorbent was characterized by the techniques of Fourier transform infrared spectroscopy (FT-IR), elementary analysis, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and N 2 adsorption techniques. The results showed that the adsorption capacity increased with decreasing pH value of the initial solution. The adsorption capacity of Cr(VI) on PPC-0.8-800 was much greater than that on other materials, and maximum adsorption capacity were calculated to be 374.90 mg g −1 . Moreover, PPC-0.8-800 had superior recyclability for the removal of Cr(VI) from wastewater, about 82% of its initial adsorption capacity was retained even after five cycles. The result of kinetic simulation showed that the adsorption of Cr(VI) on the PAN-based porous carbon could be described by pseudo-second-order kinetics. The adsorption process was the ionic interaction between protonated amine groups of PPC and HCrO 4 - ions.

Adsorption of lead using a novel xanthated carboxymethyl chitosan

2013 ◽  
Vol 69 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Qingping Song ◽  
Chongxia Wang ◽  
Ze Zhang ◽  
Jiangang Gao
Keyword(s):  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Adsorption Mechanism ◽  
Ph Value ◽  
Carboxymethyl Chitosan ◽  
Langmuir Model ◽  
Maximum Adsorption Capacity ◽  
Visible Spectra ◽  
Initial Ph ◽  
Uv Visible

Adsorption of Pb(II) was studied using a novel xanthated carboxymethyl chitosan (XCC). The XCC was synthesized using the xanthation reaction of N-carboxymethyl chitosan (NCMC). The chemical structure of XCC was characterized by UV–visible spectra. The effects of initial pH value of the solutions, contact time and adsorption isotherms on adsorption of Pb(II) were investigated. Moreover, the possible adsorption mechanism was identified using Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The experimental results showed XCC experienced a high adsorption capacity. The adsorption isotherm followed the Langmuir model. The maximum adsorption capacity obtained from the Langmuir model was 520.8 mg/g. Thermodynamic studies revealed a spontaneous and exothermic adsorption process. FTIR and XPS studies showed that the carboxyl groups, nitrogen atoms and sulfur atoms participated in the adsorption of Pb(II).

scholarly journals Comparative study on the synthesis of magnetic ferrite adsorbent for the removal of Cd(II) from wastewater

2018 ◽  
Vol 36 (7-8) ◽  
pp. 1456-1469 ◽  
Author(s):  
Fang Liu ◽  
Kanggen Zhou ◽  
Quanzhou Chen ◽  
Aihe Wang ◽  
Wei Chen
Keyword(s):  
Aqueous Solution ◽  
Wastewater Treatment ◽  
Adsorption Capacity ◽  
Settling Velocity ◽  
Ph Value ◽  
Cost Effective ◽  
Precipitation Method ◽  
Maximum Adsorption Capacity ◽  
Effects Of Ph ◽  
Magnetic Ferrites

The magnetic ferrites were synthesized at ambient temperature through the precipitation method in aqueous solution at varying pH values and were used as novel adsorbents for heavy metal-containing wastewater treatment. The magnetic ferrites were applied for the removal of Cd(II) ion from wastewater. The synthesized magnetic ferrites were characterized by settling velocity, X-ray diffraction, scanning electron microscopy, laser particles size analyzer, and vibrating sample magnetometer. The effects of pH value and contact time on the adsorption process were investigated. The magnetic ferrites had a saturation magnetization value of 82.30 emu/g and a settling velocity of 2%, indicating easy separation from aqueous solution under magnetic field. The adsorption of Cd(II) onto the magnetic ferrites followed the pseudo-second-order kinetics and the Langmuir isotherm model. The most suitable pH condition for the synthesis of magnetic ferrite with optimal Cd(II) adsorption capacity was 9.0, and a maximum adsorption capacity of 160.91 mg/g for Cd(II) ions can be achieved. Based on the cost analysis, the magnetic ferrite was a cost-effective adsorbent for Cd-containing wastewater treatment.

scholarly journals Efficient adsorption of benzoic acid from aqueous solution by nitrogen-containing activated carbon

2018 ◽  
Vol 2017 (3) ◽  
pp. 686-694 ◽  
Author(s):  
Hangdao Qin ◽  
Rong Xiao ◽  
Renhui Zhang ◽  
Jing Chen
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Benzoic Acid ◽  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Ph Value ◽  
Point Of Zero Charge ◽  
Dispersion Force ◽  
Solution Ph ◽  
Efficient Treatment

Abstract Adsorption is an efficient treatment process to remove benzoic acid from aqueous solution. In this study, nitrogen-containing surface groups were introduced onto activated carbon (AC) surface by modification with ammonium hydroxide, ammonium carbonate, melamine or urea. The nitrogen-containing AC samples were characterized using N2 adsorption-desorption, Boehm titration, determination of the pH of the point of zero charge (pHpzc) and X-ray photoelectron spectroscopy. The adsorption of benzoic acid from aqueous solution by nitrogen-containing AC has been studied. The Langmuir model fitted the experimental data of equilibrium isotherms better than the Freundlich model. At initial solution pH 2.1, the adsorption capacity was closely related with the amount of pyridinic and pyrrolic N on the AC surface, which indicated these two nitrogen-containing groups played an important part in the adsorption process. The enhancement of adsorption capacity was due to the strengthened π–π dispersion force between benzoic acid and the AC basal plane. Since the surface charge of AC as well as the existence form of benzoic acid varied with solution pH value, the adsorption capacity was found to be highest at pH 3.8 and dropped sharply at higher or lower pH values.

scholarly journals Synthesis of a Novel Ce-bpdc for the Effective Removal of Fluoride from Aqueous Solution

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Changqing Zhao ◽  
Yanwei Cui ◽  
Fang Fang ◽  
Si Ok Ryu ◽  
Jiarui Huang
Keyword(s):  
Adsorption Capacity ◽  
Removal Efficiency ◽  
Photoelectron Spectroscopy ◽  
Ph Value ◽  
Binding Capacity ◽  
Fluoride Removal ◽  
Maximum Adsorption Capacity ◽  
Fluoride Ions ◽  
X Ray ◽  
Fluoride Adsorption

Ce-1,1′-biphenyl-4,4′-dicarboxylic acid (Ce-bpdc), a novel type of metal organic framework, was synthesized and applied to remove excessive fluoride from water. The structure and morphology of Ce-bpdc were measured by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The effects, such as saturated adsorption capacity, HCO3-, and pH, were investigated. The optimal pH value for fluoride adsorption was the range from 5 to 6. The coexisting bicarbonate anions have a little influence on fluoride removal. The fluoride adsorption over the Ce-bpdc adsorbent could reach its equilibrium in about 20 min. The Ce-bpdc coordination complex exhibited high binding capacity for fluoride ions. The maximum adsorption capacity calculated from Langmuir model was high up to 45.5 mg/g at 298 K (pH = 7.0) and the removal efficiency was greater than 80%. In order to investigate the mechanism of fluoride removal, various adsorption isotherms such as Langmuir and Freundlich were fitted. The experimental data revealed that the Langmuir isotherm gave a more satisfactory fit for fluoride removal. Finally, the tested results of ground water samples from three places, Yuefang, Jiangji, and Sanyi which exhibited high removal efficiency, also demonstrate the potential utility of the Ce-bpdc as an effective adsorbent.

scholarly journals Study on Adsorption of Nickel and Methylene Blue in Aqueous Solution by Magnetic Carboxylate-Rich Carbon

2021 ◽  
Vol 37 (2) ◽  
Author(s):  
Doan Van Dat ◽  
Nguyen Hoai Thuong ◽  
Tran Thi Kieu Ngan ◽  
Le Thi Thanh Nhi ◽  
Dao My Uyen ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Adsorption Capacity ◽  
Ph Value ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
High Adsorption ◽  
Endothermic Process ◽  
High Adsorption Capacity

In this study, magnetic carboxylate-rich carbon material (Fe3O4@CRC) was synthesized via a low-temperature carbonization method and applied as an adsorbent for adsorption of Ni(II) ions and methylene blue (MB) in aqueous solution. The synthesized Fe3O4@CRC was characterized by various techniques (XRD, FTIR, FE-SEM, TEM, EDX, VSM, and BET). The adsorption kinetics, isotherms, thermodynamics, and the effects of key adsorption factors, including the pH value, initial adsorbate concentration, contact time, adsorbent dose and temperature were investigated in detail. The results showed that Fe3O4@CRC exhibited a high adsorption capacity for MB and Ni(II) with the maximum adsorption capacity of 187.26 mg/g and 106.75 mg/g, respectively. The adsorption of MB and Ni(II) on Fe3O4@CRC was a spontaneous and endothermic process, and was best described with the first-order kinetic model, Freundlich (for MB) and Langmuir (for Ni(II)) isotherm models. In addition, Fe3O4@CRC could maintain a high adsorption capacity after many consecutive cycles. Therefore, the Fe3O4@CRC material can be used as a highly efficient adsorbent for the removal of heavy metals and dyes from wastewater due to the advantages of high adsorption performance, easy separation, and good reusability.  

Removing Cd(II) from Aqueous Solution by Inverse Opal Hybrid SiO2

NANO ◽  
2020 ◽  
Vol 15 (04) ◽  
pp. 2050047
Author(s):  
Yanhong Wang ◽  
Xiuli Wang ◽  
Cuihong Wu ◽  
Xiaomei Wang ◽  
Xu Zhang
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Ph Value ◽  
Pore Wall ◽  
Ionic Concentration ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Inverse Opal ◽  
Solution Ph ◽  
Adsorption Desorption

A hybrid adsorbent with inverse opal (IO) structure was prepared for removing Cd(II) from aqueous solution. The functional polymeric chains were grafted from the pore wall of IO silica to prepare the porous hybrid material by surface-initiated atom-transfer radical polymerization. Furthermore, the amidation reaction was carried out to obtain diethylenetriamine-modified hybrid adsorbent (IO SiO2-g-PAA-DETA). Batch adsorption of removing Cd(II) onto IO SiO2-g-PAA-DETA was studied as the effect of solution pH, adsorbent doses, contact time, ionic concentration, and temperature. When the grafted amount was 73%, the maximum adsorption capacity was obtained. The optimum adsorbent dose and pH value for adsorbing Cd(II) were found to be 5[Formula: see text]g/L and 0.5[Formula: see text]g/L, respectively. The adsorption capacity was almost unaffected by Na[Formula: see text] at low concentrations. The adsorption data was depicted by the corresponding models and the results displayed that adsorbing Cd(II) on IO SiO2-g-PAA-DETA followed the Freundlich and pseudo-first-order model. In addition, after six adsorption–desorption cycles, IO adsorbent could remain above 80% of the first adsorption ability while it was washed using 0.025[Formula: see text]M EDTA.

scholarly journals Adsorption behavior of Cr(VI) by N-doped biochar derived from bamboo

2020 ◽  
Vol 15 (1) ◽  
pp. 170-181 ◽  
Author(s):  
Bei Chu ◽  
Kento Terao ◽  
Yoshimasa Amano ◽  
Motoi Machida
Keyword(s):  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Gas Flow ◽  
Adsorption Process ◽  
Adsorption Equilibrium ◽  
Great Influence ◽  
High Specific Surface Area ◽  
Equilibrium Data ◽  
Initial Adsorption ◽  
Adsorption Equilibrium Data

Abstract In this study, N-doped biochar BZ-9.5AG-30 min was prepared from bamboo by using ZnCl2 as activator and heat treated at 950 °C under NH3 gas flow for the removal of Cr(VI). The adsorbent was characterized by BET, and the amount of introduced nitrogen content and nitrogen species on BZ-9.5AG-30 min was examined by CHN elemental analyzer and X-ray photoelectron spectroscopy, respectively. Herein, the obtained BZ-9.5AG-30 min had a high specific surface area (1,610 m2/g) and high N content (4.52%). The pH of the solution had a great influence on the adsorption process, indicating that the acid condition is conducive to the adsorption process of Cr(VI). Adsorption equilibrium data of Cr(VI) were analyzed by the Langmuir and the Freundlich models. The adsorption equilibrium data were well described by the Langmuir model, and BZ-9.5AG-30 min has excellent adsorption capacity for Cr(VI) (4.31 mmol/g). BZ-9.5AG-30 min showed superior recyclability, and after five times regenerations, the adsorption capacity of BZ-9.5AG-30 min still had 63% of the initial adsorption capacity.

scholarly journals Rapid Adsorption Removal of Triclosan and p-chloro-m-xylenol In Water By Nitrogen Doped Magnetic Porous Carbon

2021 ◽  
Author(s):  
Qiuxing Li ◽  
Li Huang ◽  
Paijin Zhu ◽  
Min Zhong ◽  
Shuxia Xu
Keyword(s):  
Adsorption Capacity ◽  
Porous Carbon ◽  
Photoelectron Spectroscopy ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
One Pot ◽  
X Ray ◽  
Order Kinetic Model ◽  
Endothermic Process ◽  
The One

Abstract Contamination of water resources with organic substances like phenolic fungicides is undesirable due to the improvement of living standards, huge production and consumption of daily chemicals, and an increase in the population. In this study, ZIF-67(Co) was synthesized using the “one pot method”, and the Co-magnetic porous carbon (Co-NPC) was prepared by ZIF-67 (Co) carbonization in an atmosphere of N2. The materials were tested using a X-ray diffractometer (XRD), scanning electron microscope (SEM), infrared spectroscopy (IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption and magnetization analysis. These methods indicated that the Co-NPC was successfully prepared. With the original morphology of ZIF-67 (Co) crystal, the Co-NPC also has good porosity, magnetic properties and a large specific surface area. In water, Co-NPC-800 has a good adsorption capacity for triclosan (TCS) and p-chloro-m-xylenol (PCMX), which are kinds of aromatic fungicides. The adsorption of Co-NPC-800 on both reached equilibrium within 3 min, which is in accordance with the quasi-second-order kinetic model. At 298 K, the maximum adsorption capacity of Co-NPC-800 for TCS and PCMX was 163 and 39 mg·g-1, respectively. The adsorption of TCS and PCMX by Co-NPC-800 is a spontaneous endothermic process with reduced entropy. The combination of Co-NPC-800 and phenols come from multiple action of electrostatic, π-π and hydrogen bond effects. Moreover, Co-NPC-800 can be regenerated through simple washing and can be reused several times. Therefore, Co-NPC-800 has great potential to be applied across sewage treatments and other environmental fields.

Synthesis of Lignin-Base Bead Adsorbent and its Application in Removing Pb (II) from Aqueous Solution

2011 ◽  
Vol 391-392 ◽  
pp. 773-777 ◽  
Author(s):  
Ya Ling Huang ◽  
Ru Lin Fu ◽  
Zhen Kun Huang ◽  
Xian Su Cheng
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Ph Value ◽  
Maximum Adsorption Capacity ◽  
Condensation Polymerization ◽  
High Concentration ◽  
Modified Lignin ◽  
Scanning Electron ◽  
Better Than

A spherical amine modified lignin-base adsorbent had been prepared (L-BAA) by condensation polymerization of lignin with epoxy chloropropane and diamines. The modified products were characterized by FTIR spectra and scanning electron microscopy. Few researches on adsorbing Pb (II) of high concentration from aqueous had been reported. The spherical lignin-base adsorbent was used to adsorb Pb (II) of high concentration from aqueous solution. The effect of shaking time, pH value and temperature on adsorption had been investigated in the study. It was indicated that the adsorption was dependent on pH and temperature of Pb (II) aqueous solution. The maximum adsorption capacity was 151.0 mg/g at follow condition: pH value was 4.00 and temperature was 35°C. The adsorption capacity was better than other reported adsorbents.

Utilization of Waste of Enzymes Biomass as Biosorbent for the Removal of Dyes from Aqueous Solution in Batch and Fluidized Bed Column

2020 ◽  
Vol 71 (1) ◽  
pp. 1-12
Author(s):  
Salman H. Abbas ◽  
Younis M. Younis ◽  
Mohammed K. Hussain ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor ◽  
...  
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Particle Size ◽  
Adsorption Capacity ◽  
Fluidized Bed ◽  
Flow Rate ◽  
Fungal Biomass ◽  
Solution Flow Rate ◽  
Maximum Adsorption Capacity ◽  
Solution Flow

The biosorption performance of both batch and liquid-solid fluidized bed operations of dead fungal biomass type (Agaricusbisporus ) for removal of methylene blue from aqueous solution was investigated. In batch system, the adsorption capacity and removal efficiency of dead fungal biomass were evaluated. In fluidized bed system, the experiments were conducted to study the effects of important parameters such as particle size (701-1400�m), initial dye concentration(10-100 mg/L), bed depth (5-15 cm) and solution flow rate (5-20 ml/min) on breakthrough curves. In batch method, the experimental data was modeled using several models (Langmuir,Freundlich, Temkin and Dubinin-Radushkviechmodels) to study equilibrium isotherms, the experimental data followed Langmuir model and the results showed that the maximum adsorption capacity obtained was (28.90, 24.15, 21.23 mg/g) at mean particle size (0.786, 0.935, 1.280 mm) respectively. In Fluidized-bed method, the results show that the total ion uptake and the overall capacity will be decreased with increasing flow rate and increased with increasing initial concentrations, bed depth and decreasing particle size.

Sign in / Sign up

Export Citation Format

Share Document