Removal Of Ammonium Ions Research Articles

Recycling of raw corn cob residues as an agricultural waste material for ammonium removal: kinetics, isotherms, and mechanisms

Corn cob is an agricultural by-product worldwide available in large amounts. In this study, the potential of raw corn cob as a natural lignocellulosic waste material of no economic value was investigated for the removal of ammonium ions from aqueous solution. Sorption capacities of raw granular corn cob (GCC) for ammonium ions were evaluated in simulated and actual wastewater samples. The FT-IR analysis indicated the presence of different functional groups involved in a surface interaction with ammonium ions. Maximum removal efficiency of ammonium by raw GCC was found to be 56% achieved within 60 min contact time. Optimum pH range for the sorption of ammonium ions was found to be 4.5 to 9.5. The sorption of ammonium ions by GCC was best fitted to Freundlich isotherm. Pseudo-second order kinetic model was found to adequately describe the ammonium sorption process. In general, the results revealed that raw corn cob residues demonstrate good capacity for ammonium-nitrogen uptake.

Removal of ammonium ions by laboratory-synthesized zeolite linde type A adsorption from water samples affected by mining activities in Ghana

Ammonium ion adsorption by laboratory-synthesized zeolite (linde type A; LTA) was investigated in batch kinetics experiments. Synthesized zeolite LTA was characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy and particle size analysis. Water samples were taken from the Nyam and Tano rivers in Ghana, and 0.8 g of zeolite was added to 100 ml portions of each sample. Portions of the samples were withdrawn every 30 min for 150 min and the concentration of ammonia in each sample was determined. The removal efficiency of zeolite LTA was evaluated by retrieving the zeolite from the water samples and adding to a fresh sample to repeat the process. Equilibrium data were fitted by Langmuir and Freundlich isotherms. Maximum adsorption capacities were 72.99 mg g(-1) for samples from the River Nyam and 72.87 mg g(-1) for samples from the River Tano. The equilibrium kinetic data were analysed using adsorption kinetic models: pseudo-first order and pseudo-second order kinetic models. Linear regression was used to estimate the adsorption and kinetic parameters. The results showed that the adsorption followed pseudo-second order kinetics and suggest that zeolite LTA is a good adsorbent for the removal of nitrogen ammonia from water.

Eco-Friendly Synthesis of Nanozeolite NaA from Rice Husk Ash and its Efficiency in Removing Ammonium Ions

The eco-friendly synthesis of nanozeolite need to be developed in order to minimize the consumption of unwanted excess extracted solutions or solvents and maximize the utilization of beneficial wastes as its raw materials. Thus, the synthesis of nanozeolite NaA from rice husk ash (RHA) without extraction of silica from RHA and without organic template has been successfully achieved. Nanozeolite NaA was synthesized from rice husk ash (RHA) via this main step: aging the aluminosilicate suspension (3.190 Na2O: Al2O3: 1.4SiO2:235.07H2O) for 3 days at room temperature with agitation rate of 150 rpm followed by heating at 55 °C for 18 hours. The nanozeolite NaA was confirmed by XRD, FTIR, FESEM and particle size distribution analysis where the highest particle size was in the range of 100 to 400 nm. Its efficiency in removing ammonium ions in aqueous solution was found to be better than that of microsized zeolite NaA thus proved that the lower particle sizes of zeolite NaA (nanosize) tended to have higher adsorption sites and higher exchange capacity.

Adsorption behavior and mechanism of ammonium ion from aqueous solution onto nanoparticles zero valent iron

Nano zero valent iron (nZVI) has been investigated as an adsorbent for the removal of ammonium ion from aqueous solutions. Batch experiments were carried out to investigate the effect of agitation speed, pH, adsorbent dose, contact time, temperature and initial concentration on sorption efficiency. The favorable pH for maximum ammonium ion adsorption was 8.0. For the investigated initial concentration (50–150mg/L), and maximum adsorption rates were achieved almost in 20min of contact. An adsorbent dose of 0.6g was optimum for almost complete ammonium removal within 25min from a 100mg/L ammonium solution. For all contact times, an increase in ammonium concentration resulted in increase in the percent ammonium removal. The equilibrium adsorption data were best fitted with the Langmuir isotherm. The kinetics of ammonium adsorption was very well described by the pseudo-second-order kinetic model. Thermodynamic analysis showed negative values of Gibbs free energy change indicating adsorption was favorable and spontaneous, positive values of enthalpy change indicating endothermic adsorption and positive values of entropy change indicating increased disorder and randomness at the solid solution interface of ammonium ion with the adsorbent nZVI.

Removal of ammonia by clinoptilolite

The important advantage of zeolite applied to water treatment is its high porosity when comparing to other minerals. The porosity results in good hydrodynamic properties (the increase in the pressure loss on the zeolite filters is 1.5-2.0 times smaller than in the case of sand filters) and adsorption roperties, and in turn high capacity which allows for adsorption of contaminants (a clinoptilolite filter allows for removal of phytoplankton and bacteria). The increase in the application of artificial fertilizers and gradual contamination of water resulted from discharging industrial wastewater into the environment led to the contamination of the environment by nitric compounds. Wastewater contains about 15-50 mg dm-3 of nitric compounds (based on nitrogen) – ammonia salts constitute about 55-60% whereas organic forms of proteins, pesticides and aminoacids about 40-50%. Natural clinoptilolite could be applied to remove ammonium ions from water and wastewater. The ammonium ion uptake behaviour of clinoptilolite is connected to the processes of ion exchange. The main aim of this investigation is to evaluate the adsorption capacity of clinoptilolite towards ammonium ions. According to the obtained results the adsorption capacity of clinoptilolite for the removal of ammonium ions demonstrates its potential application in the treatment of water, wastewater and sanitary landfill leachate contaminated with ammonia. The highest adsorption capacity of clinoptilolite towards ammonium ions of 3.79 mg g-1 was found for the initial concentration of 300 mg L-1. The highest removal level reached by clinoptilolite for ammonium was of 99.74% for the initial concentration of ammonia of 50 mg L-1. The effect of exposure time on maximum uptake of ammonia was found to be insignificant.

Removal of ammonium ion from aqueous solutions using natural zeolite: kinetic, equilibrium and thermodynamic studies

The aim of the present study is to investigate the removal of ammonium ions from aqueous solutions using the natural Western Azerbaijan zeolite by utilizing ion exchange process. Batch experimental studies were conducted to evaluate by changing relevant parameters such as pH, dosage of adsorbent, stirring time, initial ammonium concentration, and temperature. The results clearly confirmed that all mentioned parameters have vital affects on removing ammonium ions from wastewater and effluents, so got optimized. Adsorption kinetics and equilibrium data for the removal of ammonium ion were analyzed using Langmuir and Freundlich equations. The Langmuir model fits the equilibrium data better than the Freundlich model. According to the Langmuir equation, the maximum uptake for ammonium ion was 43.47 (mg g−1). Pseudo-first-order and pseudo-second-order models were used to represent the kinetics of the process. Kinetic studies showed that the adsorption followed a pseudo-second-order reaction. The calculated thermodynamic parameters (ΔG°, ΔH°, and ΔS°) indicate that the adsorption process is feasible, spontaneous, and endothermic at 20–50 °C. Based on the experimental results, it can be suggested that the natural Western Azerbaijan zeolite has the potential of application as an efficient adsorbent for the removal of ammonium ions from aqueous solutions, and is suggested for wastewater treatment purposes.

Removal of ammonium and phosphate ions from wastewater samples by immobilized Chlorella sp.

Ammonium and phosphate ions present in wastewater sampled from the Puerto Colombia oxidation lagoon effluent were removed by immobilized microalgae Chlorella sp. The wastewater was filtered and sterilized to ensure the elimination of suspended solids and micro-organisms prior to biological post-treatment. Two different initial pH levels were tried in experiments. The biological nutrient removal at the lagoon was poor, compared to the limit of technology, i.e. 3 mg L−1 for total nitrogen and 0.1 mg L−1 for total phosphorus. After a 32 h contact period, 68% ammonium and 65% phosphate were uptaken by the immobilized biomass. Initial pH values of 6.5 or 7.5 slightly affected the biomass ability to remove these nutrients. These results indicate that immobilized microalgae can be a suitable alternative for nutrient removal.

Equilibrium and Thermodynamic Studies of the Adsorption of ammonium ions from Aqueous Solution by multi-walled carbon nanotube surface

This study was an attempt to examine to the feasibility of removing ammonium ions from aqueous solutions by using multi-walled carbon nanotube (MWCNT). The adsorption behavior of ammonium ions from aqueous solution onto multi-walled carbon nanotube (MWCNTs) was investigated as a function of several parameters such as contact time, initial ammonium ions concentration, and temperature. The removal of ammonium ions on carbon nanotube was studied at different temperatures ranging from 288 to 328 K. Thermodynamics parameters such as enthalpy (ΔH0) and entropy (ΔS0) of the procedure were −2.74 KJ/mol and −0.0083 kJ/mol K, respectively. The negative value of ΔH0 indicates that the removal of ammonium ions by MWCNT is exothermic and also the negative value of ΔG0 represents the fact that the process of removal of ammonium ions by MWCNT is spontaneous.

Pseudo-second-order kinetic equations for modeling adsorption systems for removal of ammonium ions using multi-walled carbon nanotube

Nitrogen and phosphorus compounds are very essentialelements for living organisms.However, when they aremore than needed, they can lead to eutrophication.The main purpose of this work is to kinetics study the possibilities for removal of ammonium ions from aqueous solutions by using multi-walled carbon nanotube (MWCNTs).The equilibrium time was found to be 35 min. Removal of ammonium ions was investigated using solutions with different concentrations in the range 100–140 mg/L. In this study adsorption of ammonium ions on multi-walled carbon nanotube surface has been investigated by UV-Vis spectrophotometer. The microstructure of carbon nanotubes were characterized using scanning electron microscopy (SEM).The kinetic rates were modeled by using the pseudo-first-order, pseudo-second-order, Intraparticle diffusion andElovich models. The pseudo-second-order model was found to explain the adsorption kinetics mosteffectively. It was also found that the pore diffusion played an important role in the adsorption. The results indicated a significant potential of the multi-walled carbon nanotube as an adsorbent for ammonium removal.

Kinetics for ammonium ion removal using a three-dimensional electrode system

Electrochemical oxidation of ammonium ions (NH(4)(+)) by using a three-dimensional electrode (TDE) composed of IrO(2)-Ta(2)O(5)/Ti anode and bamboo carbon was carried out in this paper. Experimental results reveal that the NH(4)(+) oxidation follows first-order kinetics at lower NH(4)(+) concentration and the rate constant is highly dependent on the applied current density, dosage of chlorine ions and initial NH(4)(+) concentration. In addition, increasing current density, more Cl(-) dosage and higher initial NH(4)(+) concentration are beneficial for NH(4)(+) removal. By inspecting the relation between rate constant and those operating factors, an overall empirical equation for estimation of the rate constant of NH(4)(+) oxidation is presented. The estimated model is in good agreement with the experimental results and it could also be used for accurate design of the TDE system.

Adsorption of Ammonium Ion by Multi-walled Carbon Nanotube: Kinetics and Thermodynamic Studies

This study was an attempt to examine the feasibility of removing ammonium ions from aqueous solutions by using multi-walled carbon nanotube (MWCNT). The adsorption behavior of ammonium ions (NH4 +) from aqueous solution onto MWCNTs was investigated as a function of several parameters such as contact time, initial ammonium ion concentration and temperature. The adsorption of ammonium ions on carbon nanotube was studied at different temperatures ranging from 288 K to 328 K. Enthalpy (ΔH0) and entropy (ΔS0) of the procedure were −2.74 KJ/mol and −0.0083 KJ/mol K, respectively. The negative value of ΔH0 indicates that the adsorption of ammonium ions onto CNTs is exothermic and that the negative value of ΔG0 represents the fact that the process of adsorption of ammonium ions onto CNTs is spontaneous. Kinetic analysis showed that the adsorption of ammonium ions on MWCNT followed the pseudo-second-order model.

Characterization, isotherm and kinetic studies for ammonium ion adsorption by light expanded clay aggregate (LECA)

The possibility of ammonium ion removal from aqueous solution using light expanded clay aggregate (LECA) was investigated in this work. FESEM and XRF analyses are used to determine the sorbent characterization. The influences of some effective parameters on ammonium ion adsorption process such as initial pH (3–9), initial ammonium ion concentration (10–100mg/L), temperature (15–45°C), and the contact time (0–180min) were studied. Also, the equilibrium behavior of LECA in ammonium ion removal was investigated in the temperature range of 15–45°C. The results showed that the equilibrium data were fitted well with two Langmuir and Freundlich isotherm models in all the studied temperature range. The maximum monolayer adsorption capacity estimated by Langmuir isotherm was obtained from 0.229 to 0.254 (mg/g). The required contact time to achieve the equilibrium condition was 150min. Also, the regression coefficients of the kinetic models and more conformity of the experimental adsorption capacity (qexp) to the calculated adsorption capacity (qcal) were confirmed that the experimental data follow the pseudo-second-order kinetic model. The controlling rate of NH4+ adsorption process by the Webber–Morris model was proved both by film diffusion and intra-particle diffusion models.

Interaction of Operational and Physicochemical Factors Leading to Gordonia amarae-Like Foaming in an Incompletely Nitrifying Activated Sludge Plant

The overgrowth of Gordonia amarae-like bacteria in the mixed liquor of an incompletely nitrifying water reclamation plant was inversely correlated with temperature (r = -0.78; P < 0.005) and positively correlated with the solids retention time (SRT) obtained a week prior to sampling (r = 0.67; P < 0.005). Drops followed by spikes in the food-to-mass ratio (0.18 to 0.52) and biochemical oxygen demand concentrations in primary effluent (94 to 298 mg liter(-1)) occurred at the initiation of G. amarae-like bacterial growth. The total bacterial concentration did not increase as concentrations of G. amarae-like cells increased, but total bacterial cell concentrations fluctuated in a manner similar to that of G. amarae-like bacteria in the pseudo-steady state. The ammonium ion removal rate (percent) was inversely related to G. amarae-like cell concentrations during accelerated growth and washout phases. The dissolved oxygen concentration decreased as the G. amarae-like cell concentration decreased. The concentrations of G. amarae-like cells peaked (2.47 × 10(9) cells liter(-1)) approximately 1.5 months prior to foaming. Foaming occurred during the late pseudo-steady-state phase, when temperature declines reversed. These findings suggested that temperature changes triggered operational and physicochemical changes favorable to the growth of G. amarae-like bacteria. Fine-scale quantitative PCR (qPCR) monitoring at weekly intervals allowed a better understanding of the factors affecting this organism and indicated that frequent sampling was required to obtain statistical significance with factors changing as the concentrations of this organism increased. Furthermore, the early identification of G. amarae-like cells when they are confined to mixed liquor (10(7) cells liter(-1)) allows management strategies to prevent foaming.

A facile synthesis of ZSM-11 zeolite particles using rice husk ash as silica source

ZSM-11 zeolite particles were prepared through in-situ extraction (extraction and conversion in a single step process) of silica from rice husk ash in the presence of other aqueous-based precursors (sodium aluminate and tetrabutyl ammonium hydroxide) following a simple hydrothermal condition at 100°C. The particles were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential thermal analysis (DTA) and field emission scanning electron microscopy (FESEM). XRD pattern confirmed the crystallization of ZSM-11 obtained at 100°C/12 days. The vibration bands at around 548 and 1221cm−1 indicated the presence of double 5-ring (D5R) in the pentasil zeolite structure of ZSM-11. The exothermic peak at 463°C in DTA curve indicated the removal of tetrabutyl ammonium ion (TBA+) which was used as a structure directing agent (SDA). FESEM image showed that nano-sized ZSM-11 particles were agglomerated in the crystals. The Si/Al ratio of ZSM-11 particles was found to be 51 as indicated by the elemental analysis with energy dispersive X-ray (EDX).

Adsorption of ammonium ion by coconut shell-activated carbon from aqueous solution: kinetic, isotherm, and thermodynamic studies

Ammonium ions are one of the most encountered nitrogen species in polluted water bodies. High level of ammonium ion in aqueous solution imparts unpleasant taste and odor problems, which can interfere with the life of aquatics and human population when discharged. Many chemical methods are developed and being used for removal of ammonium ion from aqueous solution. Among various techniques, adsorption was found to be the most feasible and environmentally friendly with the use of natural-activated adsorbents. Hence, in this study, coconut shell-activated carbon (CSAC) was prepared and used for the removal of ammonium ion by adsorption techniques. Ammonium chloride (analytical grade) was purchased from Merck Chemicals for adsorption studies. The CSAC was used to adsorb ammonium ions under stirring at 100 rpm, using orbital shaker in batch experiments. The concentration of ammonium ion was estimated by ammonia distillate, using a Buchi distillation unit. The influence of process parameters such as pH, temperature, and contact time was studied for adsorption of ammonium ion, and kinetic, isotherm models were validated to understand the mechanism of adsorption of ammonium ion by CSAC. Thermodynamic properties such as ∆G, ∆H, and ∆S were determined for the ammonium adsorption, using van't Hoff equation. Further, the adsorption of ammonium ion was confirmed through instrumental analyses such as SEM, XRD, and FTIR. The optimum conditions for the effective adsorption of ammonium ion onto CSAC were found to be pH 9.0, temperature 283 K, and contact time 120 min. The experimental data was best followed by pseudosecond order equation, and the adsorption isotherm model obeyed the Freundlich isotherm. This explains the ammonium ion adsorption onto CSAC which was a multilayer adsorption with intraparticle diffusion. Negative enthalpy confirmed that this adsorption process was exothermic. The instrumental analyses confirmed the adsorption of ammonium ion onto CSAC.

Amelioration of photofermentative hydrogen production from molasses dark fermenter effluent by zeolite-based removal of ammonium ion

One of the challenges in the development of integrated dark and photofermentative biological hydrogen production systems is the presence of ammonium ions in dark fermentation effluent (DFE). Ammonium strongly inhibits the sequential photofermentation process, and so its removal is required for successful process integration. In this study, the removal of ammonium ions from molasses DFE using a natural zeolite (clinoptilolite) was investigated. The samples were treated with batch suspensions of Na-form clinoptilolite. The ammonium ion concentration could be reduced from 7.60 mM to 1.60 mM and from 12.30 mM to 2.40 mM for two different samples. Photofermentative hydrogen production on treated and untreated molasses DFE samples were investigated in batch photobioreactors by an uptake hydrogenase deleted (hup−) mutant strain of Rhodobacter capsulatus. Maximum hydrogen productivities of 1.11 mmol H2/Lc·h and 1.16 mmol H2/Lc·h and molar yields of 79% and 90% were attained in the treated DFE samples, while the untreated samples resulted in no hydrogen production. The results showed that ammonium ions in molasses DFE could be effectively removed using clinoptilolite by applying a cost-effective, simple batch process.

Optimization of ammonium removal from waste water by natural zeolite using central composite design approach

The aims of the present study are to investigate removal of ammonium ion from wastewater using natural Western Azarbaijan zeolite and to optimize effective parameters by experimental design. In order to remove ammonium ions from aqueous solutions, experiments were carried out using column method as functions of the initial ammonium concentration, flow rate and pH of the solution. The results clearly confirmed that all mentioned parameters have vital affects on removing ammonium ions from wastewater and effluents, so got optimized. Central composite design with response surface methodology was applied for the optimization of main experiment parameters. The significance of the independent variables and their interactions were tested by the analysis of variance ANOVA and f-test statistics. Optimization of the variables for maximum removal efficiency by natural zeolite was performed using the quadratic model. The model predicted maximum removal efficiency under the optimum conditions including initial ammonium concentration of 30 mg l−1; flow rate of 1 ml min−1 and pH 6, which was very close to the experimental value determined in column experiment. The cation exchange capacity of natural Western Azarbaijan zeolite was found to be 1.79 meq g−1. Based on the experimental results, it can be concluded that the natural Western Azarbaijan zeolite has an excellent potential for removing ammonium ions from aqueous solutions and it is suggested as a suitable material for wastewater treatment.

Nitrate and ammonium ions removal from groundwater by a hybrid system of zero-valent iron combined with adsorbents

Nitrate (NO(3)(-)) is a commonly found contaminant in groundwater and surface water. It has created a major water quality problem worldwide. The laboratory batch experiments were conducted to investigate the feasibility of HCl-treated zero-valent iron (Fe(0)) combined with different adsorbents as hybrid systems for simultaneous removal of nitrate (NO(3)(-)) and ammonium (NH(4)(+)) ions from aqueous solution. The maximum NO(3)(-) removal in combined Fe(0)-granular activated carbon (GAC), Fe(0)-filtralite and Fe(0)-sepiolite systems was 86, 96 and 99%, respectively, at 45 °C for 24 h reaction time. The NO(3)(-) removal rate increased with the increase in initial NO(3)(-) concentration. The NO(3)(-) removal efficiency by hybrid systems was in the order of sepiolite > filtralite > GAC. The NH(4)(+) produced during the denitrification process by Fe(0) was successfully removed by the adsorbents, with the removal efficiency in the order of GAC > sepiolite > filtralite. Results of the present study suggest that the use of a hybrid system could be a promising technology for achieving simultaneous removal of NO(3)(-) and NH(4)(+) ions from aqueous solution.

Applicability comparison of different models for ammonium ion adsorption by multi-walled carbon nanotube

The aim of the present research was to remove ammonium ions (NH4+) from aqueous solution using multi-walled carbon nanotubes (MWCNTs). The adsorption behavior of ammonium ions (NH4+) from aqueous solution by multi-walled carbon nanotubes (MWCNTs) was investigated as a function of some parameters such as contact time, initial ammonium ion concentration, and temperature. Adsorption equilibrium data for the removal of ammonium ions were examined by fitting the experimental data to various models. Six isotherm models were used to describe the isotherm experiment data. Langmuir, Freundlich, and Halsey isotherm models provided much better isotherm data fitting than the other isotherm models (Temkin, D–R, and Harkins–Jura). The Langmuir equation was found to best represent the equilibrium data for ammonium ion-MWCNT system. The average relative errors (ARE) value demonstrated that the Langmuir provided the best model for these data.

A Facile Hydrothermal Conversion of Rice Husk Ash to ZSM‐5 Zeolite Powders

The ZSM‐5 zeolite powders were prepared through in situ extraction (extraction and conversion in single step process) of silica from rice husk ash in the presence of other aqueous‐based precursors (sodium aluminate and tetrapropyl ammonium hydroxide) following a simple hydrothermal condition at 130°C–170°C. The powders were characterized by X‐ray diffraction (XRD), thermogravimetry analysis (TGA), differential thermal analysis (DTA), Fourier transform infrared (FTIR) spectroscopy, N2 physisorption measurements, and field emission scanning electron microscopy (FESEM). Crystallizations of ZSM‐5 were noticed at 130°C/96 h, 150°C/24 h, and 170°C/12 h. The exothermic peak at 422°C in DTA curve indicated the removal of tetrapropyl ammonium ions (TPA+) used as structure directing agent (SDA). The vibration bands at around 550 and 1221 cm−1 indicated the presence of double 5‐ring in ZSM‐5. The 150°C–170°C‐treated samples exhibited higher BET surface area and pore volume compared to those of 130°C‐treated powders. The FESEM images showed coffin‐shaped morphology of the powders, and their sizes increased with increase in both reaction temperature and time.