scholarly journals Performance evaluation of zirconium silicate composite for removal of cadmium and zinc ions

Author(s):  
Lamis A. Attia ◽  
N.M. Sami ◽  
H.S. Hassan ◽  
Sayed Metwally

Abstract The purification of wastewater is preferred using the adsorption technique by the column due to the high efficiency of the process. The column studies are achieved to predict the removal of pollutants and clarify the adsorption capability of these pollutants in the treatment process of wastewater. Zinc and cadmium ions are presented in both radioactive and industrial wastes. Consequently, this work focused on the removal of zinc and cadmium ions from polluted wastewater using a fixed-bed column. Zirconia–silicate composite (ZrO2–SiO2) was produced using the sol-gel technique and analyzed for this purpose. Various parameters as bed depth (2, 3, and 5 cm), flow rate (2 and 3 mL/min), and initial ions concentrations (50–200 mg/L) were investigated. The column performance was computed to be 80.3 and 79.3% for Zn2+ and Cd2+, respectively, at the optimum conditions (3 cm bed depth, 2 mL/min flow rate, and 100 mg/L ions concentration). Thomas, Adams–Bohart, and Yoon–Nelson models were performed to estimate the breakthrough curves and compute the column model parameters which are valuable for process design. Thomas model presented the highest R2 values (0.84–0.97) and offered the most accurate estimation of the adsorption process.

2011 ◽  
Vol 287-290 ◽  
pp. 1620-1625
Author(s):  
Yan Wu ◽  
Zai Fang Deng ◽  
Yang Tao ◽  
Xue Gang Luo

Fixed-bed column studies for the removal of Ag(Ⅰ) and Cr(Ⅲ) from individual aqueous solutions using puffed rice husk were investigated in this work. The experiments were conducted to study the effect of important column parameters such as bed height, feed flow rate and feed initial concentration of solution. It was found that increasing bed depth yielded longer service time while increase in influent concentration and flow rate resulted in faster breakthrough. Bed Depth Service Time (BDST) model was applied to analyze the experimental data and the model parameters were evaluated. Good agreement of the experimental breakthrough curves with the model predictions was observed.


2014 ◽  
Vol 496-500 ◽  
pp. 259-263 ◽  
Author(s):  
Zhi Hui Du ◽  
Ming Chun Jia ◽  
Jin Feng Men

Two spherical composite adsorbents namely polyacrylonitrilepotassium cobalt hexacyanoferrates (PAN-KCoCF) and polyacrylonitrilepotassium nickel hexacyanoferrates (PAN-KNiCF) were synthesized. The effects of liquid flow rate, bed height and presence of other cations on the adsorption of cesium were investigated by conducting fixed-bed columns. The results showed that the column performed well at lowest flow rate for PAN-KNiCF. Flow rate examined had little influence on the adsorption of PAN-KCoCF. The breakthrough time decreased with decreasing bed height for both PAN-KCoCF and PAN-KNiCF. In addition, the existence of K+, Na+, NH4+, Ca2+and Mg2+in solution caused a reduction of maximum adsorption capacity for both of the composites. The bed depth service time (BDST) model and the Thomas model were used to analyze the experimental data and the model parameters were evaluated. Good agreement of the experimental breakthrough curves with the model predictions was observed.


2018 ◽  
Vol 18 (2) ◽  
pp. 294 ◽  
Author(s):  
Amina Abdel Meguid Attia ◽  
Mona Abdel Hamid Shouman ◽  
Soheir Abdel Atty Khedr ◽  
Nevin Ahmed Hassan

The goal of this article describes the potential of utilizing jojoba leaves and also modified with chitosan as an efficient adsorption materials for Congo red dye removal in a fixed-bed column. Inlet dye concentration, feed flow rate and bed height had a great influence on determining the breakthrough curves. The percentage dye removal was found to be approximately 69% of coated jojoba leaves with flow rate 3 mL/min, initial concentration 50 mg/L and 4 cm bed height. The dye uptake capacity at equilibrium (qe) for coated jojoba leaves showed higher values than that found for jojoba leaves. On this basis, this implies that the amino groups played an important role during the adsorption process. Breakthrough curves were satisfactorily in good agreement with both Thomas and Yoon-Nelson models based on the values of correlation coefficient (R2 ≥ 96).This study serves as a good fundamental aspect of wastewater purification on jojoba leaves as a novel adsorbent for the uptake of Congo red dyes from aqueous solution in a column system.


2013 ◽  
Vol 19 (4) ◽  
pp. 461-470 ◽  
Author(s):  
R. Rajeshkannan ◽  
M. Rajasimman ◽  
N. Rajamohan

A continuous fixed bed study was carried out by using tamarind seed as a sorbent for the removal of malachite green (MG) and acid blue 9(AB9) from aqueous solution. The effect of factors, such as flow rate and bed depth was studied. Data confirmed that the breakthrough curves were dependent on flow rate and bed depth. Thomas, Adams-Bohart, and Yoon-Nelson models were applied to experimental data to predict the breakthrough curves using non-linear regression and to determine the characteristic parameters of the packed bed column. Bed depth/service time analysis (BDST) model was used to express the effect of bed depth on breakthrough curves. The results showed that Thomas model was found suitable for the normal description of breakthrough curve at the experimental condition, while Adams-Bohart and Yoon-Nelson model were able to explain only the initial part of dynamic behaviour of the tamarind seed column. The data were in good agreement with BDST model. It was concluded that the tamarind seed can be effectively used as a sorbent for the removal of dyes.


2021 ◽  
Vol 891 ◽  
pp. 31-36
Author(s):  
Jirah Emmanuel T. Nolasco ◽  
Camille Margaret S. Alvarillo ◽  
Joshua L. Chua ◽  
Ysabel Marie C. Gonzales ◽  
Jem Valerie D. Perez

Continuous fixed-bed column studies were performed using nanocomposite beads made up of chitosan, polyethyleneimine, and graphene oxide as adsorbents for the removal of methyl orange (MO) in water. The effects of different operating parameters such as initial MO concentration (5, 10, and 15 ppm), bed height (10, 17.5, and 25 cm), and flow rate (27, 43, and 58 mL/min) were investigated using an upward-flow fixed-bed column set-up. The breakthrough curves generated were fitted with Adams-Bohart, Thomas, Yoon-Nelson, and Yan et al. models. The results showed that Yan et al. model agreed best with the breakthrough curves having an R2 as high as 0.9917. Lastly, design parameters for a large-scale adsorption column were determined via scale-up approach using the parameters obtained from column runs.


2018 ◽  
Vol 8 (11) ◽  
pp. 2221 ◽  
Author(s):  
Olga Długosz ◽  
Marcin Banach

Vermiculite has been used for the removal of Cu 2 + and Ag + from aqueous solutions in a fixed-bed column system. The effects of initial silver and copper ion concentrations, flow rate, and bed height of the adsorbent in a fixed-bed column system were investigated. Statistical analysis confirmed that breakthrough curves depended on all three factors. The highest inlet metal cation concentration (5000 mg/dm3), the lowest bed height (3 cm) and the lowest flow rate (2 and 3 cm3/min for Ag + and Cu 2 + , respectively) were optimal for the adsorption process. The maximum total percentage of metal ions removed was 60.4% and 68.7% for Ag+ and Cu2+, respectively. Adsorption data were fitted with four fixed-bed adsorption models, namely Clark, Bohart–Adams, Yoon–Nelson and Thomas models, to predict breakthrough curves and to determine the characteristic column parameters. The adsorbent was characterized by SEM, FTIR, EDS and BET techniques. The results showed that vermiculite could be applied as a cost-effective sorbent for the removal of Cu 2 + and Ag + from wastewater in a continuous process.


2020 ◽  
Vol 990 ◽  
pp. 177-182
Author(s):  
Toungrat Janpattanapong ◽  
Kowit Piyamongkala ◽  
Von Louie R. Manguiam

The modified sugarcane bagasse with aluminum sulfate was used as an adsorbent for the removal of soluble oil wastewater. The effects of the flow rate, 5 and 10 cm3/min and the number of columns used were thoroughly investigated in a continuous up-flow adsorption process. At the flow rate of 5 cm3/min respected to the 2nd column, the highest breakthrough point to adsorb soluble oil wastewater was at 6 hrs. The results confirmed that the modified sugarcane bagasse can be used as an adsorbent for fixed-bed continuous adsorption of soluble oil wastewater from steel pipe factory. The breakthrough curves were predicted by Yoon-Nelson model. This model may be fitted to predict the overall breakthrough curve using the experimental data gathered. In addition, the significant uptake of the soluble oil wastewater was demonstrated by the changes in the heat of combustion of the modified sugarcane bagasse before and after the adsorption process.


2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Bo Bai ◽  
Xiaohui Xu ◽  
Changchuan Li ◽  
Jianyu Xing ◽  
Honglun Wang ◽  
...  

The adsorptive removal of antibiotics from aqueous solutions is recognized as the most suitable approach due to its easy operation, low cost, nontoxic properties, and high efficiency. However, the conventional regeneration of saturated adsorbents is an expensive and time-consuming process in practical wastewater treatment. Herein, a scalable adsorbent of magnetic Fe3O4@chitosan carbon microbeads (MCM) was successfully prepared by embedding Fe3O4 nanoparticles into chitosan hydrogel via an alkali gelation-thermal cracking process. The application of MCM composites for the adsorptive removal of doxycycline (DC) was evaluated using a fixed-bed column. The results showed that pH, initial concentration, flow rate, and bed depth are found to be important factors to control the adsorption capacity of DC. The Thomas and Yoon-Nelson models showed a good agreement with the experimental data and could be applied for the prediction of the fixed-bed column properties and breakthrough curves. More importantly, the saturated fixed bed can be easily recycled by H2O2 which shows excellent reusability for the removal of doxycycline. Thus, the combination of the adsorption advantage of chitosan carbon with catalytic properties of magnetic Fe3O4 nanoparticles might provide a new tool for addressing water treatment challenges.


2013 ◽  
Vol 11 (1) ◽  
pp. 19-30 ◽  
Author(s):  
Xingxing Cheng ◽  
Xiaotao T. Bi

Abstract A NOx adsorption kinetic model including NO oxidation and adsorption was developed. The NOx and O2 adsorption experimental data from a fixed bed were found to be fitted well to the Freundlich type isotherm. An axial dispersion adsorption model was then developed to simulate the breakthrough curve for NOx adsorption in the fixed bed. The model parameters including mass transfer coefficient and axial dispersion coefficient were fitted from the NOx breakthrough curves measured in a fixed bed. This model can be used for design and scale-up of fixed bed NOx adsorption columns. It can also be extended for the modeling of NOx adsorption in the annulus region of the circulating fluidized bed reactor for catalytic reduction of NOx.


2019 ◽  
Vol 25 (4) ◽  
pp. 383-393
Author(s):  
Abel Adeyi ◽  
Siti Jamil ◽  
Luqman Abdullah ◽  
Thomas Choong ◽  
Mohammad Abdullah ◽  
...  

Thiourea-modified poly(acrylonitrile-co-acrylic acid) (TU-poly(AN-co-AA)) polymeric adsorbent was synthesized and characterized with Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM) and Zetasizer. Adsorptive removal of cationic malachite green (MG) dye from aqueous solution in a continuous TU-poly(AN-coAA) packed-bed column was studied. The influences of solution pH (2-9), inlet MG concentration (25-80 mg/L), bed depth (4-8 cm) and linear flow rate (1.5-5.0 mL/min) were investigated via assessment of the column breakthrough curves. Low pH and short bed depth, high MG concentration and flow rate led to early breakthrough of MG. According to correlation coefficients (R2) and sum of the squares of the errors (SSE) values, Thomas and Yoon-Nelson dynamic models are more suitable to describe the column experimental data compared to the Bohart-Adams model. TU-poly(AN-co-AA) exhibited effective separation of MG from the liquid phase and displayed high adsorption capacities after five regeneration cycles.


Sign in / Sign up

Export Citation Format

Share Document