scholarly journals The Application of Monkey Cola Pericarp (Cola lepidota) in the Removal of Toluene from Aqueous Medium

Author(s):  
C. Obi ◽  
N. C. Ngobiri ◽  
L. C. Agbaka ◽  
M. U. Ibezim-Ezeani

The study focused on the investigation of the effectiveness of the pericarp of monkey kola (Cola lepidota) biomass (CLPB) in the removal of toluene from aqueous system. X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM) and phytochemical screening methods were used for characterizing the biosorbent. The effects of contact time, pH, and concentration on biosorption process were studied. The phytochemical screening showed the presence of alkaloids, flavonoids, tannins, carbohydrate, saponins and steroids. Carboxylic, alkene and alcohol groups were found to be the principal functional groups. The highest percentage removal was 99.63% at toluene initial concentration of 40 mg/L and 98.30% at pH 8. The contact time 30 minutes gave better removal efficiency of 99.89%. Among the biosorption isotherm models tested (Langmuir, Freundlich, Dubinin Radushkevich and Temkin, respectively), the Langmuir model equation gave a better fit of the equilibrium data with a correlation coefficient (R2) of 0.99. The equilibrium data was tested with pseudo-first order and pseudo-second order models and pseudo-second order model (R² = 0.99) fitted more than the pseudo-first order model (R² = 0.85). This study has revealed that Cola lepidota is a potential biosorbent for the removal of toluene from aqueous medium under the operating conditions of contact time of 30 minutes, pH of 8 and initial concentration of 40 mg/g.

2020 ◽  
Vol 24 (2) ◽  
pp. 329-333
Author(s):  
D.O. Jalija ◽  
A . Uzairu

The objective of this study was to investigate the biosorption of Cu (II) and Ni (II) ions from aqueous solution by calcium alginate beads. The effects of solution pH, contact time and initial metal ion concentration were evaluated. The results showed that maximum Cu (II) removal (93.10%) occurred at pH of 9.0, contact time of 120 minutes and initial ion concentration of 10 mg/L while that of Ni (II) was 94.6%, which was achieved at pH of 8.0, contact time of 120 minutes and initial ion concentration of 10 mg/L. The equilibrium data fitted well to the Langmuir Isotherm indicating that the process is a monolayer adsorption. The coefficients of determination, R2, values for the Langmuir Isotherm were 0.9799 and 0.9822 respectively for Cu (II) and Ni (II) ions. The values of the maximum biosorption capacity, Qo, were 10.79 and 6.25 mgg-1 respectively. The kinetic data also revealed that the sorption process could best be described by the pseudo – second order kinetic model. The R2 values for the pseudo – second order kinetic plots for Cu (II) and Ni (II) were 0.9988 and 0.9969 respectively. These values were higher than those for the pseudo – first order plots. The values of the biosorption capacity qe obtained from the pseudo – second order plots were very close to the experimental values of qe indicating that the biosorption process follows the second order kinetics. This study has therefore shown that calcium alginate beads can be used for the removal of Cu (II) and Ni (II) ions from wastewaters. Keywords: Keywords: Adsorption, Calcium alginate, Isotherm, Langmuir, Pseudo- first order, Pseudo-second order


2011 ◽  
Vol 356-360 ◽  
pp. 1289-1292
Author(s):  
Dan Fu ◽  
Yi He Zhang ◽  
He Li Wang ◽  
Feng Zhu Lv

In this paper, the adsorption properties of TNT on Rice husk active carbon (RHAC) were investigated. The effects of contact time was examined. Kinetic data obtained at different concentrations were conducted using Lagergren’s pseudo first-order, pseudo second-order and diffusion models. The regression results showed that the adsorption kinetics was more accurately represented by pseudo second-order model. The study indicates that there is significant potential for RHAC as an adsorbent material for TNT removal from wastewater.


2019 ◽  
pp. 206-229
Author(s):  
Mallappa A. Mallappa A. Devania, Mallappa A. Devania ◽  
Basudeb Munshi

The removal of heavy metals from wastewater has become crucial to meet safe discharge standards. Development of more economic process has been strived owing to high cost of adsorbents. Thus, biosorption process has become the area of interest to researchers and engineers. The present study has carried out the transient removal of heavy metals from wastewater by both physically treated and chemically modified Cajanus cajan (Pigeon pea) husk (CCH) as novel biosorbents. Work includes five different models such as first order, second order, nth order, first order reversible and second order reversible under the heading of prediction of transient concentration of metal in the solution are used, and under the heading of prediction of transient metal uptake capacity; fractional power, pseudo first order, pseudo second order, second order reversible, Elovich, intra-particle diffusion and film diffusion models are used to analyse the kinetic data. For a metal at any particular initial concentration the best kinetic model with the least RMSE is identified. Pictorial comparison between experimental and pseudo second order and pseudo first order model predictive data of Cd(II) and Cu(II) transient biosorption, respectively onto CCH are illustrated. The trend of the results shows a successful prediction capability of all the kinetic models used in the present work. According to RMSE data, it can be concluded that the best kinetic models are pseudo second order for Cd(II) and pseudo first order for Cu(II). It has been found that the required equilibrium time is always less for the chemically activated than the physically activated sorbent. At 100 mg/L initial metal concentration, pseudo-first-order model has been identified as the best kinetic model for the transient Cu(II) and the best kinetic model for fitting the transient sorption of Cd(II) on CCH is pseudo-second-order. At initial metal concentration of 150 mg/L, initial biosorption rate of 9.7038 for Cd(II) on CCH(N) is greater than 1.4553 for Cu(II) on CCH(N). These indicate that Cd(II) undergoes faster adsorption rate than Cu(II) onto CCH.


2017 ◽  
Vol 79 (7) ◽  
Author(s):  
Abdulganiyu Umar ◽  
Mohd Marsin Sanagi ◽  
Ahmedy Abu Naim ◽  
Wan Nazihah Wan Ibrahim ◽  
Aemi Syazwani Abdul Keyon ◽  
...  

In this work, polystyrene modified-chitin was evaluated for the first time as adsorbent for the removal of Orange G from aqueous solutions. Its absorption capacity was compared to that of chitin. BET and FESEM results showed that the polystyrene-modified chitin has higher surface area (12.47 m2/g) compared to chitin (4.92 m²/g). Batch adsorption experiments on the removal of Orange G from aqueous solutions were conducted. The results showed that the polystyrene-modified chitin has improved adsorption capacity compared to chitin. The maximum adsorption of orange G by chitin occurred at pH 2, while that of the polystyrene-modified chitin occurred at pH 6. At an initial concentration of 20 mg/L, the percentages of dye removal were 65.16% and 81.20% for raw chitin (RCH) and polystyrene-modified chitin (MCH), respectively. Kinetics studies for the adsorbents were conducted using pseudo-first-order and pseudo-second-order models. The pseudo-first-order model gives poor fittings for both adsorbents, with low coefficients of determination (R2). The pseudo-second-order model fits the experimental data well, with R2 close to unity. Langmuir and Freundlich models were used to interpret the adsorption isotherms. It was found that Langmuir isotherm conformed better than Freundlich model in the adsorption of selected dye on chitin and the polystyrene-modified chitin, with R2 nearly unity.


2013 ◽  
Vol 726-731 ◽  
pp. 2191-2197 ◽  
Author(s):  
Su Yun He ◽  
Cai Yun Han ◽  
Su Fang He ◽  
Hua Wang ◽  
Chun Xia Liu ◽  
...  

This research presented the kinetic performance of arsenic absorption by mesostructure SBA-15 functionalized with Al2O3. The SBA-15 was previously synthesised and subsequently functionalized via impregnation of alumina oxides. The absorption of arsenic(V) was studied as a function of absorbent dosage and contact time. The experimental data were fitted to kinetic pseudo-first order, pseudo-second order and the intra-particle diffusion model. The pseudo-second order model presented the best correlation with the experimental data. Both surface absorption and intra-particle diffusion were acting during arsenic uptake, except for absorbent dosage of 0.1g, which was mainly controlled by the intra-particle diffusion.


2019 ◽  
Vol 9 (8) ◽  
Author(s):  
Wassila Boulaiche ◽  
Badreddine Belhamdi ◽  
Boualem Hamdi ◽  
Mohamed Trari

Abstract This work reports the application of Posidonia oceanica for the elimination of heavy metals M(II) (M = Zn, Cd, Ni, Cu and Pb) by biosorption in batch system. The effect of the contact time, initial M concentration, pH and temperature was considered. The kinetic and equilibrium models for the M-biosorption were tested namely the pseudo-first-order, pseudo-second-order and Elovich kinetic models. Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherms models have also been used to fit equilibrium adsorption data. The adsorption kinetics follow a pseudo-second-order model for all studied systems, and the equilibrium data are suitably fitted by the above models. The amount of adsorbed metals by biosorption is 48.33, 43.9, 41.02, 37.90 and 30.22 mg/g for Pb(II), Cu(II), Ni(II), Zn(II) and Cd(II), respectively. The thermodynamic parameters suggested that the metal biosorption is spontaneous with an endothermic nature.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Faranak Pishgar ◽  
Homayon Ahmad Panahi ◽  
Ali Akbar Khodaparast Haghi ◽  
Vahid Motaghitalab ◽  
Amir Hesam Hasani

Diazinon and chlorpyrifos are two common organophosphorus poisons to fight the pests in Iran. The removal of these poisons from water by thermosensitive nanosphere polymer (TNP), synthesized from the copolymerization of N-isopropylacrylamide and 3-allyloxy-1,2-propanediol, was investigated. The effect of pH, contact time, and the initial concentration on the removal amount was studied. The highest removal amount of these poisons by TNP occurred at pH 7. The contact time increase improves the removal amount and the equilibrium contact time for diazinon and chlorpyrifos was 10 and 18 min, respectively. For low concentration of less than 50 mgL−1it was shown that removal capacity remains above 95%. The initial concentration above 50 mgL−1decreased the removal amount, in which chlorpyrifos showed a greater decrease. The kinetic data has been checked using pseudo first-order, pseudo second-order, and intraparticle diffusion equations. The intraparticle diffusion model had the best conformability for the adsorption process.


Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5519
Author(s):  
Hector R. Guzmán-Carrillo ◽  
Alejandro Manzano-Ramírez ◽  
Ines Garcia Lodeiro ◽  
Ana Fernández-Jiménez

This paper reports an Alkali-Activated Materials (AAM) using two different precursors, metakaolin and a metallurgical slag with photocatalytic zinc oxide nanoparticles, as novel photocatalytic composites. The photodegradation performance of the composites using methylene blue (MB) dye as a wastewater model was investigated by ultraviolet radiations (UV-vis) spectroscopy. Adsorption in dark conditions and photodegradation under UV irradiation are the mechanisms for removing MB dye. The pseudo-first-order kinetic and pseudo-second-order kinetic models were employed, and the experimental data agreed with the pseudo-second-order model in both cases with UV and without UV irradiations. As new photocatalytic materials, these composites offer an alternative for environmental applications.


2013 ◽  
Vol 781-784 ◽  
pp. 2296-2300
Author(s):  
Jian Qiu Chen ◽  
Zhi Liang Wang ◽  
Guo Ping Li ◽  
Rui Xin Guo ◽  
Yu Zhu Hu

Sorption of Acetazolamide was found to be impacted by clay content and soil solution pH, with higher Kd values for soils with higher clay content and higher Kd values as the pH increased. Sorption data on soils were well fitted with Freundlich model (R2> 0.98). The kinetics of adsorption of Acetazolamide has been discussed using four kinetic models, i.e., the pseudo-first-order model, the pseudo-second-order model, the Elovich equation, the intraparticle diffusion model. The pseudo-first-order model and the pseudo-second-order model were both used to describe the kinetics data, and the pseudo-second-order model could describe the sorption behavior of Acetazolamide well.


2013 ◽  
Vol 743-744 ◽  
pp. 463-468
Author(s):  
Yu Dong Lu ◽  
Wen Lu Wu ◽  
Shan Lin ◽  
Rui Yun You ◽  
Zong Hua Wu

The use of camellia oleifera abel shells as biosorbent has been successfully demonstrated in the removal of Cr (VI) from aqueous solution. The effects of different parameters, such as, contact time, initial concentration of Cr (VI), pH and temperature on Cr (VI) adsorption were investigated. The results showed that the maximum uptake of Cr (VI) was up to 190.69 mg/g at a pH value of around 1.0, under the initial Cr (VI) concentration of 400mg/L and at the temperature of 298 K. The adsorption kinetics could be described by pseudo-first order and pseudo-second order kinetics models.


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