Adsorption Of Ammonium Ions Research Articles

Response surface methodology (RSM) and its application for optimization of ammonium ions removal from aqueous solutions by pumice as a natural and low cost adsorbent

Abstract This research was conducted to study the adsorption of ammonium ions onto pumice as a natural and low-cost adsorbent. The physico-chemical properties of the pumice granular were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Modeling and optimization of a NH4+ sorption process was accomplished by varying four independent parameters (pumice dosage, initial ammonium ion concentration, mixing rate and contact time) using a central composite design (CCD) under response surface methodology (RSM). The optimum conditions for maximum removal of NH4+ (70.3%) were found to be 100 g, 20 mg/l, 300 rpm and 180 min, for pumice dosage, initial NH4+ ion concentration, mixing rate and contact time. It was found that the NH4+ adsorption on the pumice granular was dependent on adsorbent dosage and initial ammonium ion concentration. NH4+ was increased due to decrease the initial concentration of NH4 and increase the contact time, mixing rate and amount of adsorbent.

Optimization of ammonia removal by natural zeolite from aqueous solution using response surface methodology

Ammonium removal from aqueous solution was investigated using natural zeolite. Operating variables were optimized by statistical design for this process. Eight variables including pH, contact time, dose and size of adsorbent, initial ammonia concentration, temperature, agitation and concentration of other adsorbate were screened by Placket-Burman design. The results indicated particle size, contact time, dose of zeolite and initial ammonia concentration are effective on removal efficiency with p-value<0.02. Optimizations of three important factors were conducted by response surface method. The optimal condition of ammonia removal in terms of removal efficiency was found to be at 0.18-0.4 mm particle size, 4 min contact time and 111 g L-1 dose of zeolite. The removal efficiency was found to be 98.25% at optimal condition. The maximum adsorption capacity of ammonium was 1.276 mg g-1 that was obtained at 0.18-0.4 mm zeolite size, 60 min contact time and 20 g L-1 zeolite dosage. The Langmuir and Freundlich isotherms adequately described the adsorption of ammonium ions by HCl-modified natural zeolite.

Local-scale recovery of wastewater nitrogen for edible plant growth.

An anaerobic/ion exchange (AN-IX) system was developed for recovery and reuse of wastewater nitrogen at point-of-origin. AN-IX combines upflow solids blanket anaerobic treatment with ammonium ion adsorption onto granular natural zeolite. AN-IX operates passively and without energy input. A 57 L empty-bed prototype was operated for 355 days on wastewater primary effluent. Total nitrogen removal exceeded 95% over the first 214 days of operation and ammonia reduction exceeded 99%; accumulation of oxidized nitrogen species (NO3(-) + NO2(-)) was not observed. The wastewater flowrate was increased during the last 35 days of operation to deliberately exhaust the ion exchange media. Spent granular media was removed from the AN-IX prototype and deployed in plant chamber experiments for cultivation of Solanum lycopersicum (cherry tomato). Wastewater nitrogen captured on zeolite was capable of supplying the total growth requirement for nitrogen. Canopy volume and plant flowering and fruiting were higher for wastewater nitrogen than for artificial fertilizer. The AN-IX process is a passive, mechanically simple and reliable system for local-scale nitrogen recovery. AN-IX is modular, scalable, adaptable and can be applied in diverse treatment contexts and recycling scenarios. AN-IX benefits include appropriate technology for local-scale nitrogen recovery, low capital and energy costs, and protection of health and the environment.

Reducing nitrogen loss and salinity during ‘struvite’ food waste composting by zeolite amendment

Struvite formation during composting through supplementation of Mg and P salts conserved nitrogen but in the same time increased the electrical conductivity (EC) of the compost limiting its application. Therefore the present study aimed at utilizing zeolite to control the EC under ‘struvite’ composting of food waste. Zeolite at 5% and 10% (dry weight basis) was supplemented to the composting mass receiving Mg and P salts and compared with treatment with Mg and P salts only and the control without any amendment. Addition of Mg and P salts effectively buffered the pH to ∼8.0 but also increased the EC of the compost to 6.45mS/cm. Co-amendment with 10% zeolite effectively reduced the EC down to 2.82mS/cm and improved compost maturity. It also increased the adsorption of ammonium ions reducing ammonia loss to 18% resulting in higher total nitrogen content in the final compost.

Equilibrium and kinetic study of ammonium ion adsorption by Fe3O4 nanoparticles from aqueous solutions

Fe3O4 nanoparticles were used as efficient adsorbent for the quick removal of ammonium ion from the solvent phase. The developed adsorbent was synthesized using a chemical co-precipitation method from its precursor mixtures i.e. FeCl2·4H2O and FeCl3·6H2O and which was further characterized using various analytical techniques such as Transmission electron microscopy and X-ray powder diffraction. The effect of various influential parameters such as contact time, pH, temperature and initial concentration was determined and optimized through a batch adsorption experiment. The optimized values of contact time, pH, temperature and initial concentration for adsorption were found to be 40min, pH10, T: 298K and 140mg/L of ammonium ions, respectively. The adsorption capacity of Fe3O4 to adsorb ammonium ion in aqueous solution was well investigated and elucidated. The adsorption equilibrium data was found to be well fitted and in good agreement with the Langmuir isotherm model, which clearly depicts the strong interaction between the developed adsorbent and the ammonium ions; which directly leads to the rapid adsorptions of ammonium ion from the aqueous solution.

Kinetic, thermodynamic, and equilibrium studies for adsorption of ammonium ion on modified polyurethane

Modified polyurethane (APU) was used as an absorbent for removal of aqueous ammonium. The surface structure of polyurethanes were modified by covalent bonding of carboxylic functional group of alginate. Effects of various operation parameters (such as temperature and pH) on adsorption capacities of APU for ammonium ion were investigated. Langmuir and Freundlich models were fitted on experimental data. It was found that Freundlich model described best for adsorption of ammonium ion onto APU. The values of Freundlich parameter KF was found to be 0.276, 0.367, and 0.406 (mg/mg)/(mg/L)1/n at temperature of 288, 298, and 308 K, respectively. Analysis of kinetic data showed that adsorption of ammonium ion follows pseudo-first-order kinetics. The value of first-order kinetic coefficient, k1, was found to be 7.93 × 10−3, 1.37 × 10−2, 1.45 × 10−2 h−1 at 288, 298, and 308 K, respectively. The values of standard free energies at different temperatures were within −22.76 to −26.81 kJ/mol with higher value at higher applied temperature. The value of standard enthalpy was found to be −0.40 kJ/mol. The optimum pH for ammonium ion adsorption onto APU was found within pH range 5–7. Results reveal that application of APU can be beneficial for removal of aqueous ammonium; hence, it can improve the quality of water.

Production, characterization, and evaluation of activated carbons from de-oiled canola meal for environmental applications

The objective of this study was the utilization of waste canola meal to produce activated carbons for environmental applications. Activated carbons were produced from de-oiled canola meal (DOCM) by slow-pyrolysis followed by physical (steam and CO2) and chemical (NH3 and KOH) activations. Physico-chemical characteristics of the precursor and activated carbons were investigated using BET, FTIR, SEM, TGA, Boehm, CHNSO, and particle size analysis. The effect of activation methods on porous structure and surface chemistry of activated carbons was investigated. Activated carbons produced from canola meal were evaluated for their efficiency as adsorbents for ammonium ion adsorption from aqueous solutions. The effect of pH, surface area, and surface functional groups of activated carbons was examined on adsorption of ammonium ion at 260.0mg/L. The role of both porous structure and surface functionality of activated carbons was studied as a function of adsorption of ammonium ion. The results showed that the maximum adsorption (qe) of ammonium ion was 55.4mg/g for steam activated carbon, 17.9mg/g for CO2 activated carbon, 56.7mg/g for ammonia-treated activated carbon, and 148mg/g for KOH activated carbon.

Thermodynamics and kinetics of adsorption of ammonium ions by graphene laminate electrodes in capacitive deionization

Electrodes made of graphene laminates (GL) with favourable electrochemical properties were used to remove sodium and ammonium ions by membrane capacitive deionization (MCDI). First, the electrosorption mechanisms of the GL-based electrodes were investigated by adsorption isotherms, kinetic models and thermodynamics under different concentrations of aqueous sodium chloride (NaCl). The ion sorption followed the Langmuir isotherm corresponding to monolayer adsorption and indicated a physisorption process according to thermodynamic parameters. The GL-based electrodes were then used to remove ammonium chloride (NH4Cl). With an initial concentration of 400mg/L, the NH4Cl removal capacity was 15.3mg/g at 20°C with a removal efficiency of 99%, indicating similar electrosorption characteristics to NaCl. A higher removal rate of ammonium ions was demonstrated compared to that of sodium, confirming that the GL-based capacitive deionization (CDI) process can effectively remove ammonium ions from aqueous solutions.

Evaluation of the Removal of Ammonium by Kaolin, Synthesized Zeolite Produced from Kaolin and Magnetic Zeolit from Aqueous Solutions

Background: Ammonium has introduced to environment by various resources such as industrial, domestic and agricultural effluents. Ammonium is toxic which can lead to oxygen depletion in the water and threating aquatic. On the current method for ammonium removal from water and wastewater is ion exchange and adsorption of the ion by zeolite. The objective of this study was removing of ammonium by Kaolin, zeolite synthesized from Kaolin and magnetic zeolite from aqueous solutions. Methods: In this study, various concentrations of Kaolin and synthesized zeolite (0.5, 1, 1.5, 2, 2.5 g/l) within aqueous solution containing ammonium ions (1- 20 mg/l) with different contact time (10-240 min) and pH values (3, 5, 7, 9, and 11) were probed. Using SEM, XRD and FTIR analysis, chemical characterization of synthesis Zeolite were studied.n Results: The maximum ammonium adsorption occurred at pH=7 and in 240 minutes contact time. By increasing initial concentration of ammonium, its sorption capacity was increased. However, by increasing the adsorbent dose, the removal efficiency was decreased. Optimum dosage of kaolin and zeolite was 2 g/L and 1.5 g/L, respectively. The isotherm data of ammonium were correlated reasonably well by Freundlich isotherm model. It was found that the adsorption of ammonium ion on kaolin, synthesis zeolite and magnetic zeolite followed pseudo-second order kinetic model. Conclusion: This research confirmed that the adsorption of ammonium by Kaolin, synthesized Zeolite and magnetic Zeolite is a low-cost and high-efficient method.

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.

Georgian zeolites for extraction of useful components from natural and waste waters.

Ni-modified Khekordzula clinoptilolyte is characterized by high adsorption capacity against hydrogen sulfide, and HNaX- modified Khekordzula clinoptilolyte has high adsorption capacity against potassium and ammonium ions. Thus, the abovementioned zeolites may be used for selective adsorption of hydrogen sulfide, potassium and ammonium ions.

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.

Adsorption of ammonium and phosphate by feather protein based semi-interpenetrating polymer networks hydrogel as a controlled-release fertilizer

A new feather protein-grafted poly(potassium acrylate)/polyvinyl alcohol (FP-g-PKA/PVA) semi-interpenetrating polymer networks (semi-IPNs) hydrogel was produced through graft copolymerization with FP as a basic macromolecular skeletal material, acrylic acid as a monomer and PVA as a semi-IPNs polymer. The adsorption of ammonium and phosphate ions from aqueous solution using the new hydrogel as N and P controlled-release fertilizer with water-retention capacity was studied. The effects of pH value, concentration, contact time and ion strength on NH 4+ and removal by FP-g-PKA/PVA semi-IPNs hydrogel were investigated using batch adsorption experiments. The results indicated that the hydrogel had high adsorption capacities and fast adsorption rates for NH 4+ and in wide pH levels ranging from 4.0 to 9.0. Kinetic analysis presented that both NH 4+ and removal were closely fitted with the pseudo-second-order model. Furthermore, the adsorption isotherms of hydrogel were best represented by the Freundlich model. The adsorption–desorption experimental results showed the sustainable stability of FP-g-PKA/PVA semi-IPNs hydrogel for NH 4+ and removal. Overall, FP-g-PKAPVA could be considered as an efficient material for the removal and recovery of nitrogen and phosphorus with the agronomic reuse as a fertilizer.

Ammonium Ion Adsorption and Settleability Improvement Achieved in a Synthetic Zeolite-Amended Activated Sludge

Municipal wastewater treatment plants typically exhibit two classic problems: high ammonium concentration in water after conventional biological treatment and, in some cases, poor activated sludge sediment ability. Potential solutions to these problems were investigated by adding a synthetic zeolite obtained from coal fly ash to different steps of activated sludge treatment. The experimental results for ammonium removal fit well with the theoretical adsorption isotherms of the Freundlich model with a maximum adsorption capacity of 13.72 mg·g−1. Utilization of this kind of zeolite to improve activated sludge sediment ability is studied for the first time in this work. It is found that the addition of the zeolite (1 g·L−1) to an activated sludge with settling problems significantly enhances its sediment ability and compact ability. This is confirmed by the sludge volume index (SVI), which was reduced from 163 ml·g−1 to 70 ml·g−1, the V60 value, which was reduced from 894 ml·L−1 to 427 ml·L−1, and the zeta potential (ζ), which was reduced from −19.81 mV to −14.29 mV. The results indicate that the addition of this synthetic zeolite to activated sludge, as an additional waste management practice, has a positive impact on both ammonium removal and sludge settleability.

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.

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.

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.

Dsorption of Ammonium (NH4 +) From Aqueous Solution by Ünye Bentonite

In this study, ammonium (NH4+) removal from aqueous media was investigated by using bentonit clay. Different concentrations of ammonium ion adsorption from aqueous solutions were examined at a room temperature. Adsorption data were applied to Langmuir and Freundlich models. In addition, the experimental results of adsorption applied to thermodynamic equations of free enthalpy of adsorption process, enthalpy and entropy values were found. Thus, whether voluntary and adsorption effects of temperature on adsorption or not was investigated. In addition, raw and treated clay ammonium (NH4+- bentonite) characterization of samples were established by using thermal analysis and infrared (IR) techniques.

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.

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.