scholarly journals PENURUNAN KADAR LOGAM KADMIUM MENGGUNAKAN ADSORBEN NANO ZEOLIT ALAM ACEH

2017 ◽  
Vol 6 (1) ◽  
pp. 1-6
Author(s):  
Cut Raziah ◽  
Zerlinda Putri ◽  
Atika Rahmi Lubis ◽  
Sofyana ◽  
Zuhra ◽  
...  

The presence of Cadmium (Cd) in groundwater is an issue that needs serious handling as it causes problems to human health. The removal of Cadmium (Cd) can be done by various methods such as adsorption, oxidation, filtration, and many more. In this study, the method used was adsorption using Aceh natural zeolite. This process was expected to reduce Cd metal as effectively as possible. The adsorption was conducted by varying contact time, adsorbent dosage, pH and initial concentration of Cd metal. The crystallized Aceh natural zeolite was characterized by X-Ray Fluorescence (XRF) with Si/Al zeolite ratio of 4.36 %. The concentration of Cadmium in water was analyzed by means of Atomic Adsorption Spectrophotometer (AAS) standard AA 630. The results showed that the adsorption of cadmium in water solution by Aceh natural zeolite occurred according to   the Freundlich adsorption model. While the adsorption kinetic from the process was found to be a pseudo second order with k2 value of 1.53.

Author(s):  
Alica Pastierová ◽  
Maroš Sirotiak

Abstract This paper presents a study into dynamic behaviour of the methylene blue adsorption (MB) on activated carbon. Effect of four parameters were studied: effect of the adsorbent dosage, effect of contact time, effect of pH, and effect of the initial concentration of methylene blue. The adsorption kinetic data were modelled using the pseudo-first and pseudo-second orders. Results show that, based on the experimental data, the pseudo-second order could be considered satisfactory. Thermodynamic parameters proved that adsorption of dye was spontaneous owing to increase in temperature and endothermic nature. Taguchi method was applied to determine the optimum conditions for removal of methylene blue by activated carbon. The optimum conditions were found to be pH = 7, contact time 60 min, initial concentration of MB 4 mg/L.


2013 ◽  
Vol 12 (06) ◽  
pp. 1350044 ◽  
Author(s):  
N. M. MUBARAK ◽  
M. RUTHIRAAN ◽  
J. N. SAHU ◽  
E. C. ABDULLAH ◽  
N. S. JAYAKUMAR ◽  
...  

The effectiveness of stannum ( Sn 2+) removal from aqueous solution by using magnetic biochar and functionalized multiwalled carbon nanotube (FMWCNT) was investigated. The effect of various factors, namely pH, adsorbent dosage, agitation speed and contact time was statistically studied through analysis of variance (ANOVA). Statistical analysis revealed that the optimum conditions for the highest removal of Sn 2+ are at pH 5, dosage 0.1 g with agitation speed and time of 100 rpm and 90 min, respectively. At the initial concentration of 0.1 mg/L, the removal efficiency of Sn 2+ using FMWCNTs was 93% and 85% with magnetic biochar. The Langmuir and Freundlich constant for both FMWCNTs and magnetic biochar were 13.397 L/mg, 18.634 L/mg and 17.719 L/mg, 25.204 L/mg, respectively. Hence, results prove that FMWCNTs are a better adsorbent with a higher adsorption capacity compared to magnetic biochar. Adsorption kinetic obeyed pseudo-second-order.


Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 486
Author(s):  
Alcina Johnson Sudagar ◽  
Slávka Andrejkovičová ◽  
Fernando Rocha ◽  
Carla Patinha ◽  
Maria R. Soares ◽  
...  

Metakaolins (MKs) prepared from low-grade kaolins located in the Alvarães (A) and Barqueiros (B) regions of Portugal were used as the aluminosilicate source to compare their effect on the compressive strength and heavy metal adsorption of geopolymers. Natural zeolite, an inexpensive, efficient adsorbent, was used as an additive in formulations to enhance geopolymers’ adsorption capacities and reduce MK utilization’s environmental footprint. Geopolymers were synthesized with the replacement of MK by zeolite up to 75 wt.% (A25, B25—25% MK 75% zeolite; A50, B50—50% MK 50% zeolite; A75, B75—75% MK 25% zeolite; A100, B100—100% MK). The molar ratios of SiO2/Al2O3 and Na2O/Al2O3 were kept at 1 to reduce the sodium silicate and sodium hydroxide environmental impact. Geopolymers’ crystallography was identified using X-ray diffraction analysis. The surface morphology was observed by scanning electron microscopy to understand the effect of zeolite incorporation. Chemical analysis using X-ray fluorescence spectroscopy and energy dispersive X-ray spectroscopy yielded information about the geopolymers’ Si/Al ratio. Compressive strength values of geopolymers obtained after 1, 14, and 28 days of curing indicate high strengths of geopolymers with 100% MK (A100—15.4 MPa; B100—32.46 MPa). Therefore, zeolite did not aid in the improvement of the compressive strength of both MK-based geopolymers. The heavy metal (Cd2+, Cr3+, Cu2+, Pb2+, and Zn2+) adsorption tests exhibit relatively higher adsorption capacities of Barqueiros MK-based geopolymers for all the heavy metals except Cd2+. Moreover, zeolite positively influenced divalent cations’ adsorption on the geopolymers produced from Barqueiros MK as B75 exhibits the highest adsorption capacities, but such an influence is not observed for Alvarães MK-based geopolymers. The general trend of adsorption of the heavy metals of both MK-based geopolymers is Pb2+ > Cd2+ > Cu2+ > Zn2+ > Cr3+ when fitted by the Langmuir isotherm adsorption model. The MK and zeolite characteristics influence geopolymers’ structure, strength, and adsorption capacities.


Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 217
Author(s):  
Marin Ugrina ◽  
Martin Gaberšek ◽  
Aleksandra Daković ◽  
Ivona Nuić

Sulfur-impregnated zeolite has been obtained from the natural zeolite clinoptilolite by chemical modification with Na2S at 150 °C. The purpose of zeolite impregnation was to enhance the sorption of Hg(II) from aqueous solutions. Chemical analysis, acid and basic properties determined by Bohem’s method, chemical behavior at different pHo values, zeta potential, cation-exchange capacity (CEC), specific surface area, X-ray powder diffraction (XRPD), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), as well as thermogravimetry with derivative thermogravimetry (TG-DTG) were used for detailed comparative mineralogical and physico-chemical characterization of natural and sulfur-impregnated zeolites. Results revealed that the surface of the natural zeolite was successfully impregnated with sulfur species in the form of FeS and CaS. Chemical modification caused an increase in basicity and the net negative surface charge due to an increase in oxygen-containing functional groups as well as a decrease in specific surface area and crystallinity due to the formation of sulfur-containing clusters at the zeolite surface. The sorption of Hg(II) species onto the sulfur-impregnated zeolite was affected by the pH, solid/liquid ratio, initial Hg(II) concentration, and contact time. The optimal sorption conditions were determined as pH 2, a solid/liquid ratio of 10 g/L, and a contact time of 800 min. The maximum obtained sorption capacity of the sulfur-impregnated zeolite toward Hg(II) was 1.02 mmol/g. The sorption mechanism of Hg(II) onto the sulfur-impregnated zeolite involves electrostatic attraction, ion exchange, and surface complexation, accompanied by co-precipitation of Hg(II) in the form of HgS. It was found that sulfur-impregnation enhanced the sorption of Hg(II) by 3.6 times compared to the natural zeolite. The leaching test indicated the retention of Hg(II) in the zeolite structure over a wide pH range, making this sulfur-impregnated sorbent a promising material for the remediation of a mercury-polluted environment.


2015 ◽  
Vol 14 (04) ◽  
pp. 1550009 ◽  
Author(s):  
N. M. Mubarak ◽  
Y. T. Fo ◽  
Hikmat Said Al-Salim ◽  
J. N. Sahu ◽  
E. C. Abdullah ◽  
...  

The study on the removal of methylene blue (MB) and orange-G dyes using magnetic biochar derived from the empty fruit bunch (EFB) was carried out. Process parameters such as pH, adsorbent dosage, agitation speed and contact time were optimized using Design-Expert Software v.6.0.8. The statistical analysis reveals that the optimum conditions for the maximum adsorption of MB are at pH 2 and pH 10, dosage 1.0 g, and agitation speed and contact time of 125 rpm and 120 min respectively. While for orange-G, at pH 2, dosage 1.0 g, and agitation speed and contact time of 125 rpm and 120 min respectively. The maximum adsorption capacity of 31.25 mg/g and 32.36 mg/g for MB and orange-G respectively. The adsorption kinetic for both dyes obeyed pseudo-second order.


2013 ◽  
Vol 684 ◽  
pp. 194-197
Author(s):  
Yi Ke Li ◽  
Bing Lu Zhao ◽  
Wei Xiao ◽  
Run Ping Han ◽  
Yan Qiang Li

The effect of contact time and the determination of the kinetic parameters of adsorption of methyl orange (MO) from aqueous solution onto Iron-Oxide-Coated-Zeolite (IOCZ) powder are important in understanding the adsorption mechanism. The effect of contact time on adsorption quantity was studied at different initial concentration and temperature, respectively. The pseudo-second-order model was adopted to fit the experimental data using non-linear regressive analysis and it was used to predict the adsorption behavior. The results showed that the process of adsorption MO was endothermic and chemisorption. The pore diffusion was not significant.


2012 ◽  
Vol 66 (8) ◽  
pp. 1699-1707 ◽  
Author(s):  
A. K. Giri ◽  
R. K. Patel ◽  
P. C. Mishra

In this work, the biosorption of As(V) from aqueous solutions by living cells of Bacillus cereus has been reported. The batch biosorption experiments were conducted with respect to biosorbent dosage 0.5 to 15 g/L, pH 2 to 9, contact time 5 to 90 min, initial concentration 1 to 10 mg/L and temperature 10 to 40 °C. The maximum biosorption capacity of B. cereus for As(V) was found to be 30.04 at pH 7.0, at optimum conditions of contact time of 30 min, biomass dosage of 6 g/L, and temperature of 30 ± 2 °C. Biosorption data were fitted to linearly transformed Langmuir isotherms with R2 (correlation coefficient) >0.99. Bacillus cereus cell surface was characterized using AFM and FTIR. The metal ions were desorbed from B. cereus using both 1 M HCl and 1 M HNO3. The pseudo-second-order model was successfully applied to predict the rate constant of biosorption.


2020 ◽  
Vol 15 (2) ◽  
pp. 460-471
Author(s):  
T. Unugul ◽  
F. U. Nigiz

Abstract In this study; acid treated carbonized mandarin peel (CMP) adsorbent was prepared and the adsorption behaviour of the adsorbent for copper removal was investigated. In the adsorption studies the effects of initial metal concentration, solution pH, adsorbent dosage and contact time on the removal were investigated. As a result; the highest removal of 100% was achieved when the copper concentration in water was 5 mg/L and the adsorbent dosage was 3.75 g/L at a solution pH of 7. Isotherm studies were also done and the appropriate isotherm was obtained as the Freundlich isotherm. According to the kinetic studies, the copper adsorption onto CMP adsorbent was adopted to the pseudo-second-order adsorption kinetic. After HCl regeneration, the adsorbent maintained 94% of its activity.


2018 ◽  
Vol 382 ◽  
pp. 307-311 ◽  
Author(s):  
Jumaeri ◽  
Sri Juari Santosa ◽  
Sutarno

Adsorption of anionic dyes Congo Red (CR) on HDTMA surfactant-modified zeolite A has been studied. The zeolite A, which is synthesized from coal fly ash, was modified with surfactant hexdeciltrimethylammonium bromide (HDTMA-Br) as much as 200% cation exchange capacity (CEC) of the zeolite. The effect of pH, contact time and initial concentration on the CR adsorption has been evaluated.The adsorption was carried out in a batch reactor at various pH, contact time and initial concentration on the given temperature. The amount CR adsorption varies as a function of pH, contact time and initial concentration of solution. Adsorption model of Langmuir and Freundlich from empirical data is used for this experiment. The Langmuir isotherm is more suitable for this adsorption. The experimental data fulfilled pseudo second-order kinetic models. The surfactant-modified zeolite A is more effective than zeolite A without modified on the adsorption of CR in aqueous solution.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
A. Battas ◽  
A. El Gaidoumi ◽  
A. Ksakas ◽  
A. Kherbeche

Our research aimed at the removal of nitrate ions through adsorption by local clay. A series of batch experiments were conducted to examine the effects of contact time, adsorbent characteristics, initial concentration of nitrate, pH of the solution, concentration, and granulometry of adsorbent. Adsorption isotherms studies indicated that local clay satisfies Freundlich’s model. The rate of reaction follows pseudo-second-order kinetics. Local clay successfully adsorbs nitrates at pH acid. The adsorption capacity under optimal conditions was found to be 5.1 mg/g. The adsorption yield increases with adsorbent dose and decrease with initial concentration of nitrate. The local clay was characterized by the X-ray fluorescence method (XRF), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), scanning electronics microscopy (SEM), and measurement of specific surface area (BET). The results of the study indicated that local clay is useful materials for the removal of nitrates from aqueous solutions which can be used in water treatment without any chemical modification.


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