scholarly journals Nitrogen-Doped Carbonaceous Materials for Removal of Phenol from Aqueous Solutions

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Magdalena Hofman ◽  
Robert Pietrzak
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Liquid Phase ◽  
Carbonaceous Material ◽  
Phase Changes ◽  
Waste Materials ◽  
Isotherm Models ◽  
Phenol Content ◽  
Nitrogen Doped ◽  
Adsorption Isotherm Models

Carbonaceous material (brown coal) modified by pyrolysis, activation, and enrichment in nitrogen, with two different factor reagents, have been used as adsorbent of phenol from liquid phase. Changes in the phenol content in the test solutions were monitored after subsequent intervals of adsorption with selected adsorbents prepared from organic materials. Significant effect of nitrogen present in the adsorbent material on its adsorption capacity was noted. Sorption capacity of these selected materials was found to depend on the time of use, their surface area, and pore distribution. A conformation to the most well-known adsorption isotherm models, Langmuir, and Freundlich ones, confirms the formation of mono- and heterolayer solute (phenol) coverage on the surface of the adsorbent applied herein. The materials proposed as adsorbents of the aqueous solution contaminants were proved effective, which means that the waste materials considered are promising activated carbon precursors for liquid phase adsorbents for the environmental protection.

scholarly journals Catalytic Performance of Nitrogen-Doped Activated Carbon Supported Pd Catalyst for Hydrodechlorination of 2,4-Dichlorophenol or Chloropentafluoroethane

Molecules ◽  
2019 ◽  
Vol 24 (4) ◽  
pp. 674 ◽  
Author(s):  
Haodong Tang ◽  
Bin Xu ◽  
Meng Xiang ◽  
Xinxin Chen ◽  
Yao Wang ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Liquid Phase ◽  
Gas Phase ◽  
Nitrogen Doping ◽  
Catalyst Surface ◽  
Catalytic Performance ◽  
Atomic Ratio ◽  
Pd Catalyst ◽  
Nitrogen Doped ◽  
The Stability

Nitrogen-doped activated carbon (N-AC) obtained through the thermal treatment of a mixture of HNO3-pretreated activated carbon (AC) and urea under N2 atmosphere at 600 °C was used as the carrier of Pd catalyst for both liquid-phase hydrodechlorination of 2,4-dichlorophenol (2,4-DCP) and gas-phase hydrodechlorination of chloropentafluoroethane (R-115). The effects of nitrogen doping on the dispersion and stability of Pd, atomic ratio of Pd/Pd2+ on the surface of the catalyzer, the catalyst’s hydrodechlorination activity, as well as the stability of N species in two different reaction systems were investigated. Our results suggest that, despite no improvement in the dispersion of Pd, nitrogen doping may significantly raise the atomic ratio of Pd/Pd2+ on the catalyst surface, with a value of 1.2 on Pd/AC but 2.2 on Pd/N-AC. Three types of N species, namely graphitic, pyridinic, and pyrrolic nitrogen, were observed on the surface of Pd/N-AC, and graphitic nitrogen was stable in both liquid-phase hydrodechlorination of 2,4-DCP and gas-phase hydrodechlorination of R-115, with pyridinic and pyrrolic nitrogen being unstable during gas-phase hydrodechlorination of R-115. As a result, the average size of Pd nanocrystals on Pd/N-AC was almost kept unchanged after liquid-phase hydrodechlorination of 2,4-DCP, whereas crystal growth of Pd was clearly observed on Pd/N-AC after gas-phase hydrodechlorination of R-115. The activity test revealed that Pd/N-AC exhibited a much better performance than Pd/AC in liquid-phase hydrodechlorination of 2,4-DCP, probably due to the enhanced stability of Pd exposed to the environment resulting from nitrogen doping as suggested by the higher atomic ratio of Pd/Pd2+ on the catalyst surface. In the gas-phase hydrodechlorination of R-115, however, a more rapid deactivation phenomenon occurred on Pd/N-AC than on Pd/AC despite a higher activity initially observed on Pd/N-AC, hinting that the stability of pyridinic and pyrrolic nitrogen plays an important role in the determination of catalytic performance of Pd/N-AC.

Adsorptive Removal of Ni2+ from Aqueous Solution Using Rice Husk-Based Activated Carbon

2015 ◽  
Vol 754-755 ◽  
pp. 950-954
Author(s):  
Mohd Faisal Taha ◽  
Anis Suhaila Shuib ◽  
Maizatul Shima Shaharun ◽  
Azry Borhan
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Rice Husk ◽  
Textural Properties ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Adsorption Studies ◽  
Adsorptive Removal ◽  
Equilibrium Data ◽  
Good Potential

An attempt was made to study the potential of rice husk as an alternative cheap precursor for activated carbon to remove Ni2+ from aqueous solution. Rice husk was treated chemically (with NaOH) and physically (carbonization) to prepare rice husk based activated carbon (RHAC). The textural properties of RHAC, i.e. surface area (255 m2/g) and pore volume (0.17 cm2/g), were determined by N2 adsorption using Brunauer-Emmett-Teller (BET) surface analyzer. RHAC was also characterized for its morphology and its elemental compositions. The adsorption studies for the removal of Ni2+ from aqueous solution were carried out using different dosage of RHAC as adsorbent as a function of varied contact time. The concentration of Ni2+ was determined by atomic absorption spectrometer (AAS). The results obtained from adsorption studies indicate good potential of rice husk as a cheap precursor to produce activated carbon for the removal of Ni2+ from aqueous solution. The equilibrium data from adsorption studies fitted well the of Langmuir and Freundlich isotherm models.

scholarly journals Reactive Blue 203 dye Removal Using Biosorbent: A Study of Isotherms, Kinetics, and Thermodynamics

2018 ◽  
Vol 5 (2) ◽  
pp. 91-99
Author(s):  
Marzieh Bagheri ◽  
Mohammad Nasiri ◽  
Bahareh Bahrami
Keyword(s):  
Activated Carbon ◽  
Dye Removal ◽  
Dye Adsorption ◽  
Industrial Wastes ◽  
Isotherm Models ◽  
Characterization Methods ◽  
Pine Cone ◽  
Adsorption Isotherm Models ◽  
Ft Ir ◽  
Maximum Removal

Nowadays, due to increasing usage of dye in various industries and its destructive effects on health and environment, it is necessary to remove dyes from industrial wastes. Although few studies can be found on using pine cone for removal of different dyes, it has not been used yet to remove Reactive Blue 203 (RB203) dye. The purpose of this study is to investigate RB203 dye adsorption using activated carbon produced from pine cone. Optimal values of influencing factors for RB203 dye removal were obtained. The results showed that the maximum removal was occurred at a pH of 2, temperature of 30˚C, dye concentration of 30 mg/L, adsorbent dosage of 100 mg/L, and contact time of 15 min. The maximum removal percentage was 98.48%. In order to study the synthesized activated carbon, some characterization methods including scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy and Brunauer-Emmett-Teller (BET) have been used. Investigation of adsorption isotherm models revealed that adsorption of RB203dye can be described through D-R and Temkin isotherm models. Additionally, RB203 dye removal follows the pseudo-firstorder kinetic equation.

scholarly journals Chemical and physical preparation of activated carbon using Raw bagasse for cationic dye adsorption

2016 ◽  
Vol 18 (2) ◽  
pp. 402-415 ◽  
Keyword(s):  
Activated Carbon ◽  
Sugarcane Bagasse ◽  
Contact Time ◽  
Dye Adsorption ◽  
Isotherm Models ◽  
Adsorptive Capacity ◽  
Adsorption Isotherm Models ◽  
Equilibrium Data ◽  
Agriculture Wastes ◽  
Physical Preparation

<div> <p>Agriculture wastes like sugarcane bagasse are available in large quantities in Egypt. Various adsorbents from natural materials, industrial waste materials, agricultural by-products, and biomass based activated carbon can be used in the removal of various dyes. Raw Bagasse pith (RBP) was used to prepare activated carbon (AC) using phosphoric acid (H<sub>3</sub>PO<sub>4</sub>) as a chemical activating agent. C The raw BP and the synthesized adsorbent were characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). The effectiveness of AC prepared in adsorption of methylene blue (MB) has been studied as a function of adsorbent type, initial dye concentration and contact time. The effects of the initial dye concentration and contact time were evaluated. Adsorption isotherm models - Langmuir, Freundlich and Temkin were used to simulate the equilibrium data. Langmuir equation was found to have the highest value of R<sup>2</sup> compared with other models. Furthermore, it was found that sugarcane bagasse have a high adsorptive capacity towards MB.</p> </div> <p>&nbsp;</p>

scholarly journals The Adsorption Efficiency of Chemically Prepared Activated Carbon from Cola Nut Shells by on Methylene Blue

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Julius Ndi Nsami ◽  
Joseph Ketcha Mbadcam
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
Experimental Studies ◽  
Isotherm Models ◽  
Solution Ph ◽  
Batch Mode ◽  
Initial Concentration ◽  
Adsorption Isotherm Models ◽  
Pseudo Second Order ◽  
Blue Solution

The adsorption of methylene blue from aqueous solution onto activated carbon prepared from cola nut shell has been investigated under batch mode. The influence of major parameters governing the efficiency of the process such as, solution pH, sorbent dose, initial concentration, and contact time on the removal process was investigated. The time-dependent experimental studies showed that the adsorption quantity of methylene blue increases with initial concentration and decreasing adsorbent dosage. The equilibrium time of 180 min was observed and maximum adsorption was favoured at pH 3.5. The dye removal using 0.1 g of adsorbent was more than 90%. This dosage (0.1 g) was considered as the optimum dosage to remove methylene blue from aqueous solutions. The equilibrium adsorption data were analyzed by the Freundlich, Langmuir adsorption isotherm models. The kinetics of methylene blue solution was discussed by pseudo-first-order, pseudo-second-order, and Elovich models. The adsorption process follows the Elovich rate kinetic model, having a correlation coefficient in the range between 0.9811 and 1.

scholarly journals A comprehensive study on adsorption behavior of some azo dyes from aqueous solution onto different adsorbents

2017 ◽  
Vol 76 (2) ◽  
pp. 478-489 ◽  
Author(s):  
Nihan Kaya
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Azo Dyes ◽  
Binding Capacity ◽  
Agricultural Wastes ◽  
Walnut Shell ◽  
Isotherm Models ◽  
Adsorption Parameters ◽  
Dye Pollutants ◽  
Comprehensive Study

One of the major environmental problems is the existence of dye materials in water sources. This pollutant must be removed from water by appropriate methods. Although most of these methods are efficient for the treatment of waters contaminated with dye pollutants, they are very costly and commercially unattractive. Adsorption is one of the most popular methods for the removal of dye pollutants from water especially if the sorbent is inexpensive. Sorbents are classified as natural sorbents, commercial sorbents, and the sorbents obtained from industrial and agricultural wastes. Although commercial activated carbon is widely used in wastewater treatment applications, it is very expensive. In this study, usability of inexpensive materials – sepiolite as a natural adsorbent, and walnut shell and hazelnut shell as agricultural wastes – was investigated instead of commercial activated carbon to remove some azo dyes (methyl red, methyl orange and methyl yellow) from aqueous solution. Batch experiments were carried out to determine the effect of different adsorption parameters such as pH, initial dye concentration, contact time, adsorbent dose and temperature. The equilibrium of adsorptions was modeled using Langmuir and Freundlich isotherm models. This comprehensive study showed that these alternative adsorbents had sufficient binding capacity to remove these azo dyes from water.

scholarly journals Basic Blue Dye Adsorption from Water Using Polyaniline/Magnetite (Fe3O4) Composites: Kinetic and Thermodynamic Aspects

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1764 ◽  
Author(s):  
Amir Muhammad ◽  
Anwar-ul-Haq Ali Shah ◽  
Salma Bilal ◽  
Gul Rahman
Keyword(s):  
Aqueous Solution ◽  
Dye Adsorption ◽  
Isotherm Models ◽  
Blue Dye ◽  
Adsorption Parameters ◽  
Magnetic Oxide ◽  
Magnetite Fe3o4 ◽  
Adsorption Isotherm Models ◽  
Pseudo Second Order ◽  
Enhanced Adsorption

Owing to its exciting physicochemical properties and doping–dedoping chemistry, polyaniline (PANI) has emerged as a potential adsorbent for removal of dyes and heavy metals from aqueous solution. Herein, we report on the synthesis of PANI composites with magnetic oxide (Fe3O4) for efficient removal of Basic Blue 3 (BB3) dye from aqueous solution. PANI, Fe3O4, and their composites were characterized with several techniques and subsequently applied for adsorption of BB3. Effect of contact time, initial concentration of dye, pH, and ionic strength on adsorption behavior were systematically investigated. The data obtained were fitted into Langmuir, Frundlich, Dubbanin-Rudiskavich (D-R), and Tempkin adsorption isotherm models for evaluation of adsorption parameters. Langmuir isotherm fits closely to the adsorption data with R2 values of 0.9788, 0.9849, and 0.9985 for Fe3O4, PANI, and PANI/Fe3O4 composites, respectively. The maximum amount of dye adsorbed was 7.474, 47.977, and 78.13 mg/g for Fe3O4, PANI, and PANI/Fe3O4 composites, respectively. The enhanced adsorption capability of the composites is attributed to increase in surface area and pore volume of the hybrid materials. The adsorption followed pseudo second order kinetics with R2 values of 0.873, 0.979, and 0.999 for Fe3O4, PANI, and PANI/Fe3O4 composites, respectively. The activation energy, enthalpy, Gibbs free energy changes, and entropy changes were found to be 11.14, −32.84, −04.05, and −0.095 kJ/mol for Fe3O4, 11.97, −62.93, −07.78, and −0.18 kJ/mol for PANI and 09.94, −74.26, −10.63, and −0.210 kJ/mol for PANI/Fe3O4 respectively, which indicate the spontaneous and exothermic nature of the adsorption process.

Carbonized medlar-core particles as a new biosorbent for removal of Cu2+ from aqueous solution and study of its surface morphology

2016 ◽  
Vol 74 (1) ◽  
pp. 236-245 ◽  
Author(s):  
Narges Samadani Langeroodi ◽  
Elaheh Safaei
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
High Adsorption ◽  
Langmuir Adsorption ◽  
Adsorption Isotherm Models ◽  
Freundlich Adsorption Isotherm ◽  
High Adsorption Capacity ◽  
Core Particles

The objective of this study was to investigate the use of carbonized medlar-core particles as a new biosorbent to remove Cu2+ from aqueous solution. Fourier transform infrared spectroscopy and scanning electron microscopy were used to characterize the biosorbent. This paper reports the effects of adsorbent dose, pH, temperature and concentration of adsorbate. Batch isotherm studies were also performed to understand the ability of the adsorbent. The adsorption behavior of the Cu2+ was studied using Langmuir and Freundlich adsorption isotherm models. The maximum adsorption capacity determined from the Langmuir adsorption equation has been found as 43.478 mg.g−1 at 298.15 K. The adsorption of Cu2+ by medlar core in carbonized form was spontaneous and endothermic. It was also found that the biosorption of Cu2+ followed second-order kinetics. Carbonized medlar-core particles showed great potential in aqueous solution due to the high adsorption capacity.

Removal of Hexavalent Chromium by Adsorption on Microwave Assisted Activated Carbon Prepared from Stems of Leucas Aspera

2018 ◽  
Vol 0 (0) ◽  
Author(s):  
A. Shanmugalingam ◽  
A. Murugesan
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Ion Concentration ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Batch Mode ◽  
Microwave Assisted ◽  
Leucas Aspera ◽  
Order Kinetic Model ◽  
Impregnation Time

Abstract This study reports adsorption of Cr(VI) ions from aqueous solution using activated carbon that was prepared from stems of Leucas aspera. Eight hundred and fifty watts power of microwave radiation, 12 min of radiation time, 60% of ZnCl2 solution and 24 h of impregnation time are the optimal parameters to prepare efficient carbon effective activated carbon. It was designated as MWLAC (Microwave assisted Zinc chloride activated Leucas aspera carbon). Various adsorption characteristics such as dose of the adsorbent, agitation time, initial Cr(VI) ion concentration, pH of the solution and temperature on adsorption were studied for removal of Cr(VI) ions from aqueous solution by batch mode. Also the equilibrium adsorption was analyzed by the Langmuir, Freundlich, Tempkin and D-R isotherm models. The order of best describing isotherms was given based on R2 value. The pseudo-second-order kinetic model best fitted with the Cr(VI) adsorption data. Thermodynamic parameters were also determined and results suggest that the adsorption process is a spontaneous, endothermic and proceeded with increased randomness.

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