Adsorption of chromium (VI) from aqueous solutions on activated carbon

1994 ◽  
Vol 30 (9) ◽  
pp. 191-197 ◽  
Author(s):  
R. Leyva Ramos ◽  
A. Juarez Martinez ◽  
R. M. Guerrero Coronado
Keyword(s):  
Activated Carbon ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Ph Effect ◽  
Freundlich Isotherm ◽  
Maximum Adsorption Capacity ◽  
Experimental Adsorption ◽  
Ph Values ◽  
Chromium Vi ◽  
Adsorption Data

The adsorption isotherm of chromium (VI) on activated carbon was obtained in a batch adsorber. The experimental adsorption data were fitted reasonably well to the Freundlich isotherm. The effect of pH on the adsorption isotherm was investigated at pH values of 4, 6, 7, 8, 10 and 12. It was found that at pH < 6, Cr(VI) was adsorbed and reduced to Cr(III) by the catalytic action of the carbon and that at pH ≥ 12, Cr(VI) was not adsorbed on activated carbon. Maximum adsorption capacity was observed at pH 6 and the adsorption capacity was diminished about 17 times by increasing the pH from 6 to 10. The pH effect was attributed to the different complexes that Cr(VI) can form in aqueous solution. The adsorption isotherm was also affected by the temperature since the adsorption capacity was increased by raising the temperature from 25 to 40°C. It was concluded that Cr(VI) was adsorbed significantly on activated carbon at pH 6 and that the adsorption capacity was greatly dependent upon pH.

Adsorption of cadmium(II) from aqueous solution onto activated carbon

1997 ◽  
Vol 35 (7) ◽  
pp. 205-211 ◽  
Author(s):  
R. Leyva-Ramos ◽  
J. R. Rangel-Mendez ◽  
J. Mendoza-Barron ◽  
L. Fuentes-Rubio ◽  
R. M. Guerrero-Coronado
Keyword(s):  
Activated Carbon ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Carbon Surface ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Ph Values ◽  
Average Percent Deviation ◽  
Initial Ph

The adsorption isotherm of cadmium on activated carbon was measured in a batch adsorber. Effects of temperature and solution pH on the adsorption isotherm were investigated by determining the adsorption isotherm at temperatures of 10, 25, and 40°C and at initial pH values from 2 to 8. Langmuir isotherm better fitted the experimental data since the average percent deviation was lower than with the Freundlich isotherm It was noticed that the amount of Cd2+ adsorbed was reduced about 3 times by increasing the temperature from 10 to 40°C. It was found that Cd2+ was not adsorbed on activated carbon at pH of 2 or lower and that Cd2+ was precipitated out as Cd(OH)2 at pH values above 9. Maximum adsorption capacity was observed at pH of 8 and the adsorption capacity was decreased about 12 times by reducing the initial pH from 8 to 3. According to the cadmium speciation diagram the predominant species below pH of 8 is Cd2+. Thus, cadmium was adsorbed on the activated carbon surface as Cd2+. It was concluded that the adsorption capacity is a strong function of pH and temperature.

scholarly journals Karekterisasi, Kinetika, dan Isoterm Adsorpsi Limbah Ampas Kelapa sebagai Adsorben Ion Cu(II)

SAINTIFIK ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 104-115
Author(s):  
Agusriyadin Agusriyadin
Keyword(s):  
Adsorption Capacity ◽  
Ph Effect ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Optimum Conditions ◽  
Langmuir Adsorption ◽  
Adsorbent Surface ◽  
Adsorption Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Penelitian ini bertujuan untuk menguji kemampuan AK dan AKPM dalam mengadsorpsi ion Cu (II), pengaruh parameter adsorpsi dan mekanisme adsorpsi. AK dan AKP Madsorben dibuat dari residu ampas kelapa. Adsorben dikarakterisasi dengan FTIR, SEM dan EDS. Pengaruh parameter adsorpsi seperti pH awal, dosis adsorben, waktu kontak dan konsentrasi ion Cu (II) awal diperiksa untuk menentukan kondisi optimum serapan tembaga (II). Ion Cu (II) yang teradsorpsi diukur berdasarkan pada konsentrasi Ion Cu (II) sebelum dan sesudah adsorpsi menggunakan metode AAS. Hasil karakterisasi menunjukkan bahwa struktur pori dan gugus fungsi tersedia pada permukaan adsorben. Menurut percobaan efek pH, kapasitas adsorpsi maksimum dicapai pada pH 7. Waktu kontak optimal dan konsentrasi tembaga awal (II) ditemukan masing-masing pada 120 menit dan 100 mg L-1. Data eksperimental sesuai dengan model kinetik orde dua orde dua, dan Langmuir isoterm adsorpsi yang diperoleh paling sesuai dengan data adsorpsi. Kapasitas adsorpsi maksimum adsorben ditemukan menjadi 4,73 dan 6,46 mg g-1 pada kondisi optimal. The results of characterization showed that the pore structure and the functional groups were available on adsorbent surface. According to the pH effect experiments, the maximum adsorption capacity was achieved at pH 7. Optimum contact time and initial copper(II) concentration were found at 120 min and 100 mg L-1, respectively. The experimental data were comply with the pseudo-second-order kinetic model, and Langmuir adsorption isotherm obtained best fitted the adsorption data. The maximum adsorption capacity of the adsorbents was found to be 4.73 and 6.46 mg g-1 at optimum conditions.

scholarly journals Bioadsorption of lead(II) over the pulp of Acrocomia aculeata

2021 ◽  
Vol 46 (4) ◽  
pp. 38-46
Author(s):  
Alexandra Novak ◽  
F�tima Yubero ◽  
Diana Diez-P�rez-N��ez ◽  
Fernando Luis Fertonani ◽  
Brenda Gisselle Da Silva Britez ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Column Experiments ◽  
Maximum Adsorption Capacity ◽  
Batch Experiments ◽  
Adsorption Data ◽  
Acrocomia Aculeata ◽  
Scanning Electron

The adsorption of lead in aqueous solution onto Acrocomia aculeata pulp was examined. The pulp was characterized in the presence and absence of lead using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG-DTA), and scanning electron microscopy (SEM). Sulfur and oxygen bonds were responsible for adsorbing lead onto the pulp surface. The TG-DTA profile proved that adding sodium azide increases the pulp�s thermal stability until 200 �C. Adsorption data in batch and column systems were analyzed to understand the pulp adsorption compared to other biomaterials. In the batch experiments, the removal efficiency reached a maximum of 91.9% when a solution of 50 ppm of lead was placed in contact with the pulp for 30 min and fit Freundlich isotherm behavior. In the column experiments, the theoretical maximum adsorption capacity was found to be 11.97 mg g�1; more column data is needed to compare column results to other studies. Further studies to improve the pulp adsorption capacity are needed for it to be a competitive biomaterial for water treatment.

Preparation and Chelating Properties of Polystyrene Modified Ethoxycarbonyl Thiourea Resin

2011 ◽  
Vol 239-242 ◽  
pp. 781-785 ◽  
Author(s):  
Shuai Wang ◽  
Hong Zhong ◽  
Liu Yin Xia ◽  
Zhong Nan Wang ◽  
Qian Zhang
Keyword(s):  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Maximum Adsorption Capacity ◽  
Polymer Grafting ◽  
Isotherm Equation ◽  
Adsorption Capacities ◽  
Adsorption Data ◽  
Separation Factors ◽  
Langmuir Isotherm Equation ◽  
Freundlich Adsorption Isotherm

A novel polystyrene modified ethoxycarbonyl thiourea resin(PSETU) was synthesized by polymer grafting of aminated polystyrene and ethoxycarbonyl isothiocyanate. The adsorption capacities of PSETU follow the order: Au(III) > Cu(II) > Zn(II) > Ni(II) > Fe(III) > Ca(II) ≈ Mg(II). The adsorption capacity for Au(III) increases with the increase of contact time, temperature and initial concentration of Au(III). The adsorption data fit Boyd’s diffusion equation of liquid film, Langmuir adsorption isotherm and Freundlich adsorption isotherm. The maximum adsorption capacity of PSETU calculated by Langmuir isotherm equation is 3.485 mmol/g, and the separation factors of PSETU for Au(III)-base metal ions are above 380. According to XPS results, the functional atoms of PSETU coordinate with Au(III) during the adsorption process.

scholarly journals Removal of Anionic and Cationic Dyes from Wastewater Using Activated Carbon from Palm Tree Fiber Waste

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 416
Author(s):  
Basma G. Alhogbi ◽  
Shoruq Altayeb ◽  
Effat. A. Bahaidarah ◽  
Mahmoud F. Zawrah
Keyword(s):  
Electron Microscopy ◽  
Activated Carbon ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Chemical Activation ◽  
High Yield ◽  
Maximum Adsorption Capacity ◽  
Palm Tree ◽  
Fast Method ◽  
Adsorbent Dosage

This study focuses on using a facile method for the green preparation of activated carbon (AC) from palm tree fiber (PTF) waste. The synthesized cost-effective AC was investigated for the removal of an anionic dye (Congo red, CR) and a cationic dye (Rhodamine B, RhB) from wastewater. The morphological and structural characterization of the synthesized AC were performed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), surface area, Fourier transform infrared spectroscopy (FTIR), total pore volume, average pore diameter and pore size distribution, zeta potential, and zero-point charge. To investigate the adsorption efficiency, different parameters such as adsorbent dosage, solution pH, initial dye concentration, and duration were applied using the batch experiments. Various adsorption isotherm and kinetics models were applied to study the adsorption mechanism and dynamics. The results showed that chemical activation with a weak acid (H3PO4) at 400 °C for 30 min is a fast method for the activation of each precursor and produces a high yield. The result of analysis showed an increase in the adsorption capacity at pH 2. The maximum adsorption capacity was 9.79 and 26.58 mg g−1 at 30 min for CR dye and RhB dye, respectively. The optimum adsorbent dosage for the activated carbon from palm tree fiber (PTFAC) was 0.15 g with a high percentage removal of CR (98.24%) and RhB (99.86%) dyes. The adsorption isotherm and kinetic studies were found to be favorable and feasible for assessing the adsorption of dyes with the Langmuir model and pseudo-second-order reaction, respectively. In addition, the AC showed reusability up to five cycles. The results showed that the synthesized AC was environmentally friendly and successfully removed dyes from wastewater.

The Adsorption Isotherm Studies of Orange Peel on Pesticide Furadan

2013 ◽  
Vol 477-478 ◽  
pp. 1331-1335
Author(s):  
Guang Fu Xu ◽  
Hui Min Jing ◽  
Rui Xin Guo
Keyword(s):  
Aqueous Solution ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Low Cost ◽  
Agricultural Waste ◽  
Orange Peel ◽  
Maximum Adsorption Capacity ◽  
Attractive Candidate ◽  
Adsorption Data ◽  
Langmuir And Freundlich Models

Orange peel, an agricultural waste available in large quantity in China, was utilized as low-cost adsorbent to remove furadan from aqueous solution by adsorption. Adsorption isotherms were calculated and discussed. Both Langmuir and Freundlich models fitted the adsorption data quite reasonably (R2> 0.98) and the maximum adsorption capacity was 161.29 mg.g-1. The results in this study indicated that orange peel was an attractive candidate for removing furadan from the aqueous solution.

scholarly journals Langmuir and Freundlich isotherm equation test on the adsorption process of Cu (II) metal ions by cassava peel waste (Manihot esculenta crantz)

2021 ◽  
Vol 2126 (1) ◽  
pp. 012022
Author(s):  
S Nuryanti ◽  
Suherman ◽  
S Rahmawati ◽  
M Amalia ◽  
T Santoso ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Manihot Esculenta ◽  
Contact Time ◽  
Adsorption Process ◽  
Freundlich Isotherm ◽  
Maximum Adsorption Capacity ◽  
Manihot Esculenta Crantz ◽  
Isotherm Equations ◽  
Cassava Peel

Abstract This Study aims to determine the adsorption process of Cu (II) metal by cassava peel waste (Manihot esculenta crantz) meeting the Langmuir equation and Freundlich. Research method cassava peel made into activated carbon, then determine the mass, pH and optimum contact time. Then the determination of the maximum adsorption capacity was carried out by testing with the Langmuir isotherm and Freundlich isotherm equations. The results showed that the best conditions (optimal conditions) were obtained with the addition of 0.5 grams of active carbs from cassava peels. The percentage of Cu ion adsorption in these conditions was 97.72%, at pH 6 and a contact time of 60 minutes and the absorption capacity was 98.49%. The maximum adsorption capacity of cassava peel activated carbon to Cu(II) ions at the optimum condition was determined based on the Langmuir and Freundlich isotherm equations. The results obtained were-51.813 mg/g and 26,792 mg/g, respectively.

Phenol adsorption on industrial activated carbon: evaluation of efficiency

2021 ◽  
pp. 49-54
Author(s):  
С.А.А. Ахмед ◽  
Е.С. Гогина
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
High Efficiency ◽  
Freundlich Isotherm ◽  
Isotherm Model ◽  
Maximum Adsorption Capacity ◽  
Phenol Removal ◽  
Ph Variation ◽  
Wide Ph Range ◽  
Coconut Shells

Адсорбция фенола на активированном угле считается одной из наиболее эффективных систем очистки сточных вод. В связи с этим изучена эффективность двух промышленных активированных углей российского производства для очистки сточных вод от фенола. Образцы включают порошкообразный активированный уголь (производимый из березового угля) и дробленый активированный уголь (производимый из скорлупы кокосового ореха). Исследование проведено в условиях изменения pH, влияния времени контакта и различных начальных концентраций фенола на процесс адсорбции. Исследование дополнительно расширено для выяснения кинетики адсорбции и модели изотерм Ленгмюра и Фрейндлиха. Результаты показали, что активированный уголь сохраняет максимальную адсорбционную способность в широком диапазоне pH – от 2 до 9. Это доказывает применимость угля для удаления фенола из различных сточных вод. Механизм адсорбции с использованием обоих образцов активированных углей следовал псевдовторому порядку и соответствовал модели изотермы Ленгмюра. Максимальная адсорбционная способность составила 185,19 и 172,41 мг/г для порошкообразного и дробленого угля соответственно, что свидетельствует о высокой эффективности удаления фенола из сточных вод. The adsorption of phenol on activated carbon is considered one of the most efficient wastewater treatment systems. In this regard, the effectiveness of two Russian manufactured industrial activated carbon types in removing phenol from wastewater has been studied. The samples included powdered activated carbon (made from birch charcoal) and crushed activated carbon (made from coconut shells). The study was carried out under the conditions of pH variation and the effect of contact time and different initial concentrations of phenol on the adsorption process. The study was further expanded to clarify the adsorption kinetics and the Langmuir and Freundlich isotherm model. The results showed that activated carbon retained the maximum adsorption capacity over a wide pH range of 2 to 9. This fact proves the usability of coal for removing phenol from various wastewater types. The adsorption mechanism using both activated carbon samples followed the pseudo-second order and corresponded to the Langmuir isotherm model. The maximum adsorption capacity was 185.19 and 172.41 mg/g for powdered and crushed coal, respectively, suggesting a high efficiency of phenol removal from wastewater.

scholarly journals Study of Chromium(VI) Adsorption from Aqueous Solution on to Activated Carbon

2000 ◽  
Vol 18 (2) ◽  
pp. 97-106 ◽  
Author(s):  
Ryszard Dobrowolski ◽  
Elżbieta Stefaniak
Keyword(s):  
Activated Carbon ◽  
Ionic Strength ◽  
Adsorption Capacity ◽  
Activated Carbons ◽  
Principal Mechanism ◽  
Ph Values ◽  
Chromium Vi ◽  
Major Process ◽  
Dilute Aqueous Solutions ◽  
Ppm Level

The adsorption of chromium(VI) from dilute aqueous solutions on to activated carbons at natural pH values was investigated. The activated carbons were modified to obtain materials with a well-defined surface containing inorganic impurities at ppb or ppm level. Measurements of the adsorption kinetics relative to the degree of granulation were undertaken. It was found that the reaction rate of the ions on the surface of the activated carbon rather than diffusion was the major process influencing the equilibrium. Surface reduction of CrVI to CrIII appeared to be the principal mechanism for the adsorption of chromium on the activated carbons studied. It was demonstrated experimentally that the presence of oxidizing agents dramatically changed the adsorption capacity of CrVI on the studied carbons. The influence of the ionic strength (controlled by the addition of NaCl) on the adsorption capacity was also studied. Variable and complex influences of the ionic strength on the adsorption capacity were observed.

scholarly journals Adsorption characteristic of As(III) on goethite waste generated from hydrometallurgy of zinc

2017 ◽  
Vol 75 (12) ◽  
pp. 2747-2754 ◽  
Author(s):  
Jian-Long Hu ◽  
Xiao-Song Yang ◽  
Ting Liu ◽  
Li-Nan Shao ◽  
Wang Zhang
Keyword(s):  
Wastewater Treatment ◽  
Adsorption Capacity ◽  
Raw Material ◽  
Maximum Adsorption Capacity ◽  
Distribution Analysis ◽  
Adsorption Characteristic ◽  
Wastewater Treatment Process ◽  
Ph Values ◽  
Adsorption Data ◽  
Langmuir Isotherm Model

In this paper, goethite waste from hydrometallurgy of zinc was used as a raw material for arsenic adsorbent preparation. The goethite waste adsorbent (GWA) was characterized with scanning electron microscope (SEM), X-ray powder diffraction (XRD), and particle size distribution analysis. The adsorption of As(III) on GWA was studied as a function of contact time, pH, and coexisting anions. The safety of GWA usage in the wastewater treatment process was assessed by toxicity characteristic leaching procedure (TCLP) tests. The equilibrium adsorption data fitted well with the Langmuir isotherm model, and the maximum adsorption capacity of As(III) on GWA was 51.47 mg.g−1. GWA showed higher adsorption capacity at weak alkaline pH values (7.0–9.5). The coexisting PO43− and SiO32− presented significant adsorption competition with As(III) in aquatic systems. No significant heavy metals leaching was observed for GWA and As(III) loaded GWA in TCLP tests, which implied the safety of GWA as an adsorbent for arsenic containing wastewater treatment.

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