Investigation of nitrate adsorption onto activated carbon from the pods hulls of Moringa

Coconut granular activated carbon (CGAC) was modified by impregnating with ZnCl2solution to remove nitrate from aqueous solutions. Sorption isotherm and kinetic studies were carried out in a series of batch experiments. Nitrate adsorption of both ZnCl2-modified CGAC and CGAC fitted the Langmuir and Freundlich models. Batch adsorption isotherms indicated that the maximum adsorption capacities of ZnCl2-modified CGAC and CGAC were calculated as 14.01 mgN·g−1and 0.28 mgN·g−1, respectively. The kinetic data obtained from batch experiments were well described by pseudo-second-order model. The column study was used to analyze the dynamic adsorption process. The highest bed adsorption capacity of 1.76 mgN·g−1was obtained by 50 mgN·L−1inlet nitrate concentration, 20 g adsorbents, and 10 ml·min−1flow rate. The dynamic adsorption data were fitted well to the Thomas and Yoon–Nelson models with coefficients of correlationR2 > 0.834 at different conditions. Surface characteristics and pore structures of CGAC and ZnCl2-modified CGAC were performed by SEM and EDAX and BET and indicated that ZnCl2had adhered to the surface of GAC after modified. Zeta potential, Raman spectra, and FTIR suggested the electrostatic attraction between the nitrate ions and positive charge. The results revealed that the mechanism of adsorption nitrate mainly depended on electrostatic attraction almost without any chemical interactions.

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Removal of nitrate from synthetic aqueous solution and groundwater in a continuous pilot system using chemical activated carbon derived from walnut shell

Water Practice & Technology ◽

10.2166/wpt.2016.082 ◽

2016 ◽

Vol 11 (4) ◽

pp. 784-795 ◽

Cited By ~ 5

Author(s):

Abolghasem Alighardashi ◽

Shooza Shahali

Keyword(s):

Aqueous Solution ◽

Activated Carbon ◽

Average Pore Size ◽

Fixed Bed ◽

Walnut Shell ◽

Maximum Adsorption Capacity ◽

Average Pore ◽

Langmuir Adsorption ◽

Bet Specific Surface Area ◽

Nitrate Adsorption

Excessive nitrate in the water impose a danger to human health and contribute to eutrophication. The present continuous fixed bed pilot study was carried out using granular activated carbon made from walnut shell for removal of nitrate from aqueous solution and natural groundwater. The carbon was characterized using SEM, FTIR and BET. The BET specific surface area and average pore size before nitrate adsorption were 1434.6 m2g−1 and 2.08 nm, respectively, and after were 633.28 m2g−1 and 2.04 nm, respectively. Optimum removal of nitrate was achieved at a contact time of 2 min, pH of 6.5 and a nitrate concentration of 200 mg/l. The hydraulic loading rate was calculated to be 10 m3/h.m2 and the maximum adsorption capacity using the Langmuir adsorption isotherm model (R2 = 0.99) was 10 mg NO3/g. These experiments were also carried out using groundwater and the removal of nitrate decreased from 68% to 60% because of competition with other cations and anions.

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Kinetic analysis of sucrose activated carbon for nutrient removal in water

H2Open Journal ◽

10.2166/h2oj.2020.012 ◽

2020 ◽

Vol 3 (1) ◽

pp. 208-220

Author(s):

Sara Jamaliniya ◽

O. D. Basu ◽

Saumya Suresh ◽

Eustina Musvoto ◽

Alexis Mackintosh

Keyword(s):

Activated Carbon ◽

Kinetic Analysis ◽

Adsorption Capacity ◽

Nitrate Removal ◽

Freundlich Isotherm ◽

Langmuir Model ◽

Phosphate Removal ◽

Phosphate Adsorption ◽

Isotherm Models ◽

Nitrate Adsorption

Abstract A renewable, green activated carbon made from sucrose (sugar) was compared with traditional bituminous coal-based granular activated carbon (GAC). Single and multi-component competitive adsorption of nitrate and phosphate from water was investigated. Langmuir and Freundlich isotherm models were fitted to data obtained from the nitrate and phosphate adsorption experiments. Nitrate adsorption fits closely to either Freundlich or Langmuir model for sucrose activated carbon (SAC) and GAC with a Langmuir adsorption capacity of 7.98 and 6.38 mg/g, respectively. However, phosphate adsorption on SAC and GAC demonstrated a selective fit with the Langmuir model with an adsorption capacity of 1.71 and 2.07 mg/g, respectively. Kinetic analysis demonstrated that adsorption of nitrate and phosphate follow pseudo-second-order kinetics with rate constant values of 0.061 and 0.063 g/(mg h), respectively. Competitive studies between nitrate and phosphate were demonstrated in preferential nitrate removal with GAC and preferential phosphate removal with SAC. Furthermore, nitrate and phosphate removals decreased from 75% removal to 35% removal when subject to multi-component solutions, which highlights the need for adsorption analysis in complex systems. Overall, SAC proved to be competitive with GAC in the removal of inorganic contaminants and may represent a green alternative to coal-based activated carbon.

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Modeling of Nitrate Adsorption on Granular Activated Carbon (GAC) using Artificial Neural Network (ANN)

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.1870 ◽

2009 ◽

Vol 7 (1) ◽

Cited By ~ 12

Author(s):

Alireza Khataee ◽

Ali Khani

Keyword(s):

Neural Network ◽

Activated Carbon ◽

Adsorption Process ◽

Granular Activated Carbon ◽

Spectrophotometric Analysis ◽

Ann Model ◽

Effective Parameters ◽

Neuron Network ◽

Feed Forward Back Propagation ◽

Nitrate Adsorption

High concentrations of N-containing compounds in drinking water cause health problems such as cyanosis among children and cancer of the alimentary canal. Therefore, removal of nitrate from water samples is of significant importance from the health and environmental point of view. In this work, the effective parameters on removal of nitrate by adsorption process, which included the amount of granular activated carbon (m), initial concentration (C0), contact time, pH and temperature (T), were investigated. The removal process was monitored using an on-line spectrophotometric analysis system. It was found that the content of adsorption followed decreasing order: m= 10>5>2>1g, C0= 20>15>25>10 ppm, pH=4>7>10>1 and T=25>35>45>55 0C. The three-layered feed forward back propagation neural network was used for modeling of nitrate adsorption on granular activated carbon. The comparison between the predicted results of the designed ANN model and the experimental data proved that modeling of nitrate adsorption process using artificial neuron network was a good and precise method to predict the extent of adsorption of nitrate on GAC under different conditions.

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Nitrate Adsorption by Activated Carbon

UF Journal of Undergraduate Research ◽

10.32473/ufjur.v23i.128407 ◽

2021 ◽

Vol 23 ◽

Author(s):

Adam Rosenblum

Keyword(s):

Activated Carbon ◽

Chemical Reactions ◽

Activated Carbons ◽

Chemical Activation ◽

Activated Carbon Adsorption ◽

Carbon Adsorption ◽

Food And Beverage ◽

Nitrate Adsorption ◽

Odor Removal ◽

Adsorption Rates

Activated carbon is a type of carbon that is a known catalyst for a variety of chemical reactions. Uses of activated carbon include purifying liquids and gases, food and beverage processing, odor removal, industrial pollution control, and numerous other applications. There are a variety of different activated carbons, with most being derived from coal, peat, and wood. Activated carbon is a catalyst because the small pores of the carbon increase the surface area available for adsorption or chemical reactions. One primary use of activated carbon is how it adsorbs nitrates onto its surface. This paper delves into different adsorption rates of an activated carbon (Filtrasorb 600) that is treated with different chemicals and then subjected to a chemical activation at a constant pressure under different gaseous conditions. Data collected during experiments indicate there are significant interactions between surface functional groups and nitrate. Keywords: activated carbon, adsorption, nitrates

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Nitrate adsorption by synthetic activated carbon magnetic nanoparticles: kinetics, isotherms and thermodynamic studies

Desalination and Water Treatment ◽

10.1080/19443994.2015.1079251 ◽

2015 ◽

Vol 57 (35) ◽

pp. 16445-16455 ◽

Cited By ~ 29

Author(s):

Roshanak Rezaei Kalantary ◽

Emad Dehghanifard ◽

Anoushiravan Mohseni-Bandpi ◽

Leila Rezaei ◽

Ali Esrafili ◽

...

Keyword(s):

Activated Carbon ◽

Magnetic Nanoparticles ◽

Thermodynamic Studies ◽

Nitrate Adsorption

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Magnetic Mg-Fe/LDH Intercalated Activated Carbon Composites for Nitrate and Phosphate Removal from Wastewater: Insight into Behavior and Mechanisms

Nanomaterials ◽

10.3390/nano10071361 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1361 ◽

Cited By ~ 6

Author(s):

Omar Alagha ◽

Mohammad Saood Manzar ◽

Mukarram Zubair ◽

Ismail Anil ◽

Nuhu Dalhat Mu’azu ◽

...

Keyword(s):

Activated Carbon ◽

Mesoporous Structure ◽

Phosphate Removal ◽

Phosphate Adsorption ◽

Solution Ph ◽

Adsorption Mechanisms ◽

Nitrate Adsorption ◽

Ft Ir ◽

Magnetically Separable ◽

Adsorption Desorption

This experimental work focused on the synthesis, characterization, and testing of a unique, magnetically separable, and eco-friendly adsorbent composite material for the advanced treatment and efficient removal of nitrate and phosphate pollutants from wastewater. The MgAl-augmented double-layered hydroxide (Mg-Fe/LDH) intercalated with sludge-based activated carbon (SBAC-MgFe) composites were characterized by FT-IR, XRD, BET, VSM, SEM, and TEM techniques, revealing homogeneous and efficient dispersion of MgFe/LDH within the activated carbon (AC) matrix, a highly mesoporous structure, and superparamagnetic characteristics. The initial solution pH, adsorbent dose, contact time, and temperature parameters were optimized in order to reach the best removal performance for both pollutants. The maximum adsorption capacities of phosphate and nitrate were found to be 110 and 54.5 mg/g, respectively. The competition between phosphate and coexisting ions (Cl−, CO32−, and SO42−) was studied and found to be remarkably lower in comparison with the nitrate adsorption. The adsorption mechanisms were elucidated by kinetic, isotherm, thermodynamic modeling, and post-adsorption characterizations of the composite. Modeling and mechanistic studies demonstrated that physisorption processes such as electrostatic attraction and ion exchange mainly governed the nitrate and phosphate adsorption. The composite indicated an outstanding regeneration performance even after five sequences of adsorption/desorption cycles. The fabricated composite with magnetically separable characteristics can be used as a promising adsorbent for the removal of phosphate and nitrate pollutants from wastewater.

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