scholarly journals Continuous Fixed-Bed Column Study Using Carbon Nano-Adsorbent Made Through Pyrolysis of Garbage Leachate on the Sand Particles for Removal of 4-Nonylphenol from Surface Water

2021 ◽  
Author(s):  
Mastaneh Safari ◽  
Iman Mosaddegh

The potential of carbon nanorods (NRs) derived from garbage leachate was assessed in a fixed-bed and batch system replacing the present costly approaches to treat surface water polluted by 4-Nonylphenol. First, the waste leachate was coated on silica particles and then pyrolysis was performed at 300 to 800℃. The optimum temperature for the production of nano-adsorbent was determined by analyses such as scanning electron microscopy (SEM) for adsorbent morphological characterization, X-ray energy dispersive spectrometry (EDS), and Raman test. Next, Freundlich, Langmuir, and UT isotherm models were used to analyze the batch equilibrium data. The impact of inlet 4-NP concentration (0.5, 1, and 2 mgL-1), feed flow rate (5, 10, and 20 mLmin-1), bed height (5, 10, and 15 cm), and bottom-up flow on the breakthrough features of the sorption system with a fixed bed was examined. The adsorption data were fitted using the well-known column models (i.e., Thomas, Yoon-Nelson, and Adams-Bohart). For all circumstances, the best fitting was obtained for the attained results using Yoon-Nelson and Thomas models, but not the Adams-Bohart model. The experimental data confirmed that increasing the inlet concentration and bed depth resulted in an increase in the adsorption capacity and a decrease in flow rate. After applying a different regeneration process, the results showed the effectiveness of the novel engineered substance as a reusable adsorbent for water treatment.

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Z. Z. Chowdhury ◽  
S. M. Zain ◽  
A. K. Rashid ◽  
R. F. Rafique ◽  
K. Khalid

The potential of granular-activated carbon (GAC) derived from agrowaste of Mangostene (Mangostana garcinia) fruit peel was investigated in batch and fixed bed system as a replacement of current expensive methods for treating wastewater contaminated by manganese, Mn(II) cations. Batch equilibrium data was analyzed by Langmuir, Freundlich, and Temkin isotherm models at different temperatures. The effect of inlet metal ion concentration (50 mg/L, 70 mg/L, and 100 mg/L), feed flow rate (1 mL/min and 3 mL/min), and activated carbon bed height (4.5 cm and 3 cm) on the breakthrough characteristics of the fixed bed sorption system were determined. The adsorption data were fitted with well-established column models, namely, Thomas, Yoon-Nelson, and Adams-Bohart. The results were best-fitted with Thomas and Yoon-Nelson models rather than Adams-Bohart model for all conditions. The column had been regenerated and reused consecutively for five cycles. The results demonstrated that the prepared activated carbon was suitable for removal of Mn(II) ions from wastewater using batch as well as fixed bed sorption system.


2011 ◽  
Vol 64 (3) ◽  
pp. 654-660 ◽  
Author(s):  
Xiuli Han ◽  
Wei Wang ◽  
Xiaojian Ma

The adsorption potential of lotus leaf to remove methylene blue (MB) from aqueous solution was investigated in batch and fixed-bed column experiments. Langmuir, Freundlich, Temkin and Koble–Corrigan isotherm models were employed to discuss the adsorption behavior. The results of analysis indicated that the equilibrium data were perfectly represented by Temkin isotherm and the Langmuir saturation adsorption capacity of lotus leaf was found to be 239.6 mg g−1 at 303 K. In fixed-bed column experiments, the effects of flow rate, influent concentration and bed height on the breakthrough characteristics of adsorption were discussed. The Thomas and the bed-depth/service time (BDST) models were applied to the column experimental data to determine the characteristic parameters of the column adsorption. The two models were found to be suitable to describe the dynamic behavior of MB adsorbed onto the lotus leaf powder column.


2016 ◽  
Vol 74 (7) ◽  
pp. 1585-1593 ◽  
Author(s):  
Maria R. Hartono ◽  
Ariel Kushmaro ◽  
Robert S. Marks ◽  
Xiaodong Chen

In this study, composite calcium-alginate/carbon nanotubes/TiO2 beads were prepared and tested for their potential in the removal of bisphenol A (BPA) from aqueous solutions. The removal traits were inspected using a fixed-bed sorption column. By varying parameters such as bed height (15–20 cm), flow rate (2.0–6.0 mL.min−1) and inlet BPA concentration (10–30 mg.L−1) we assessed the removal capacity of these composites. The highest sorption capacity of 5.46 mg.g−1 was achieved at 10 mg.L−1 BPA concentration, 2.0 mL.min−1 flow rate and 20 cm bed height at saturation. Adams-Bohart, Yoon-Nelson and Dose-Response isotherm models were applied to evaluate the performance of the column at different inlet concentrations. The experimental data satisfactorily fit the Dose-Response model with high correlation (r2 > 0.97) across the breakthrough curve. Regeneration of the used adsorbent beads were performed by immersion in the desorption solvent followed by light irradiation. It was postulated that inclusion of TiO2 facilitates the desorbed pollutant degradation from the used adsorbent beads.


Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 263
Author(s):  
Usman Khalil ◽  
Muhammad Bilal Shakoor ◽  
Shafaqat Ali ◽  
Sajid Rashid Ahmad ◽  
Muhammad Rizwan ◽  
...  

Chromium (Cr) in water bodies is considered as a major environmental issue around the world. In the present study, aqueous Cr(VI) adsorption onto rice husk was studied as a function of various environmental parameters. Equilibrium time was achieved in 2 h and maximum Cr(VI) adsorption was 78.6% at pH 5.2 and 120 mg L−1 initial Cr(VI) concentration. In isotherm experiments, the maximum sorption was observed as 379.63 mg g−1. Among four isotherm models, Dubinin–Radushkevich and Langmuir models showed the best fitting to the adsorption data, suggesting physical and monolayer adsorption to be the dominant mechanism. The kinetic modeling showed that a pseudo-second order model was suitable to describe kinetic equilibrium data, suggesting a fast adsorption rate of Cr(VI). The results of FTIR spectroscopy indicated that mainly –OH and C–H contributed to Cr(VI) adsorption onto rice husk. This paper provided evidence that rice husk could be a cost-effective, environment-friendly and efficient adsorptive material for Cr(VI) removal from wastewater due to its high adsorption capacity.


2020 ◽  
Vol 81 (2) ◽  
pp. 321-332 ◽  
Author(s):  
Abir Melliti ◽  
Jamel Kheriji ◽  
Hanen Bessaies ◽  
Béchir Hamrouni

Abstract The occurrence of boron in water and its inefficient removal are the key issue in desalination and water treatment. Adsorption by fixed-bed column is usually used to remove mineral and organic contaminants from the aqueous phase. The adsorption of the boron onto activated carbon, prepared from palm bark, is studied. Batch adsorption experiments are developed to determine the equilibrium time and the best isotherm model. The kinetic adsorption data can be described by the second-order equation. Among the adsorption isotherm models, Langmuir and Sips models give better fit of the equilibrium data. The calculated thermodynamic parameters show that the boron adsorption is exothermic in nature. The effects of inlet boron concentration, feed flow rate and weight of activated carbon on the fixed-bed adsorption are determined by two-level factorial experimental design. Breakthrough and saturation times are higher at high adsorbent weight and low flow rates. The increase of boron initial concentration decreases breakthrough and saturation times. The volume treated per gram of activated carbon is higher at lower initial concentrations and at higher adsorbent weight. Compared to other models, the Yan model fits better the experimental data of the breakthrough curves with R2 of 0.993.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
V. Gunasekar ◽  
V. Ponnusami

Carbon synthesized from plant leaf powder was employed for the adsorption of methylene blue from aqueous effluent. Effects of pH (2, 4, 6, 8, and 9), dye concentration (50, 100, 150, and 200 mg/dm3), adsorbent dosage (0.5, 1.0, 1.5, and 2.0 g/dm3), and temperature (303, 313, and 323 K) were studied. The process followed pseudo-second-order kinetics. Equilibrium data was examined with Langmuir and Freundlich isotherm models and Langmuir model was found to be the best fitting model with highR2and low chi2values. Langmuir monolayer adsorption capacity of the adsorbent was found to be 61.22 mg/g. From the thermodynamic analysis, ΔH, ΔG, and ΔSvalues for the adsorption of MB onto the plant leaf carbon were found out. From the values of free energy change, the process was found out to be feasible process. From the magnitude of ΔH, the process was found to be endothermic physisorption.


Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2519 ◽  
Author(s):  
Rafael Fernández-González ◽  
María Ángeles Martín-Lara ◽  
Gabriel Blázquez ◽  
Antonio Pérez ◽  
Mónica Calero

Olive cake obtained as a by-product from the olive oil industry has been evaluated as biosorbent of heavy metals from aqueous solutions in batch and continuous systems (fixed-bed columns). First, a complete study of effect of hydrothermal treatment with water on biosorption capacity of resulting solid was performed. Results showed that the values of biosorption capacity increased when the particle size of material decreased and the temperature of treatment increased. Then, hydrolyzed olive cake was treated by common chemicals (hot water, nitric acid, and sodium hydroxide) and the impact of chemical treatment was analyzed. The results were well reproduced by Langmuir and Freundlich isotherm models, getting maximum experimental biosorption capacities that changed between 42.34 mg/g obtained for the solid material modified by NaOH and 14.27 mg/g obtained for the solid material modified by nitric acid. Finally, laboratory tests in fixed-bed columns were performed with four different heavy metals and at three different inlet concentrations. The biosorption capacity increased from 2.83 mg/g (Cr), 4.51 mg/g (Cu), 12.30 mg/g (Pb), and 4.10 mg/g (Zn) to 3.08 mg/g (Cr), 5.17 mg/g (Cu), 13.21 mg/g (Pb), and 5.51 mg/g (Zn) when the concentration of metal ions increased, from 50 mg/L to 200 mg/L, respectively. Also, the experimental data obtained was successfully correlated with the Thomas, Yoon–Nelson, and dose–response models.


2019 ◽  
Vol 280 ◽  
pp. 05008
Author(s):  
Ignatius Sriyana

Due to the increasing amounts of surface runoff and land degradation in watersheds, mitigation efforts need to be taken by adopting water conservation technologies to reduce flooding and surface runoff. The purpose of this research is to study the impact of sedrainpond (SDP) and infiltration well technology procurement on surface water in order to mitigate flood disasters downstream. The method approach is carried out by measuring the field discharge, collecting rainfall data and analysing the data using ArcView GIS and Microsoft Excel. The measured discharge in the study was 1170.9 L/s. The study applies 1819 units of SDP technologies with a diameter of 1 m, a depth of 2.5 m and a total storage volume of 3573.11 m3, and 340 units of infiltration wells with a diameter of 1 m, a depth of 2 m and a total storage volume of 533.65 m3. For scenario 1, where the water contained in the well is drained in one day, the flood discharge can be reduced to 986 L/s, along with a flow rate decrease of 184.9 L/s (15.79%). While for scenario 2, where the water contained in the well is drained in two days, the flood discharge can be reduced to 1001.6 L/s with a flow rate decrease of 184.9 L/s (14.46%).


2020 ◽  
Vol 16 (1) ◽  
pp. 11-15
Author(s):  
Md Waliul Islam ◽  
Md Abul Hossain ◽  
Md Nurul Hooda ◽  
Kazi Rafiqul Abedin ◽  
Husne Ara

Objectives: To evaluate urinary symptoms and quality of life in patient with BPH before and after TURP. To determine the impact of TURP on the urinary symptoms (IPSS) and peak urinary flow rate. Methods: This study is prospective study carried out between 2010 and 2011 in the department of Urology, National Institute of Kidney Diseases & Urology. Total 102 cases were selected purposively according to selection criteria. Each patient was observed and followed up at 8 weeks (1st visit), 16 weeks (2nd visit) 24 weeks (3rd visit) after transurethral resection of prostate (TURP). IPSS score, QOL score also recorded and uroflowmetry was done to see the peak urinary flow rate (Qmax) of urine and voiding time. USG was done to see post voidal residual urine volume and DRE also done in selected cases. Data was complied and statistical analysis were done using computer based software, Statistical Package for Social Science (SPSS), using paired ‘t’ test. A P value <0.05 was taken as significance. Results: Before TURP, IPSS range 17-25 and mean 21.61+2.43, after TURP, range 0-7 and mean 4.27+1.71). Hence a significant improvement of IPSS was found from 2 months to 6 months follow up after TURP. The change was tested using “paired student ‘t’ test”. Before TURP Qmax range 7-12.2 and mean was 9.96+1.69, which became range 18-25 and mean was 22.61+2.28 after TURP and therefore change of mean Qmax was 12.64+2.69. The change was tested using “paired student ‘t’ test”. The change was found significant (P<0.001). Conclusion: Transurethral resection of prostate resolves obstructive symptoms, rapid improvement of urinary flow rate Bangladesh Journal of Urology, Vol. 16, No. 1, Jan 2013 p.11-15


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