Competitive adsorption of organic solvents using modified and unmodified calcium bentonite clay mineral

2019 ◽  
Author(s):  
Chem Int

Dodecyltrimethylammonium bromide (DTAB)–modified and unmodified calcium bentonite were both used for the competitive adsorption of aromatics (xylene, ethylbenzene and toluene) and petroleum products (gasoline, dual purpose kerosene and diesel) from their aqueous solution. Infrared spectroscopy (IR) and expansion tests (adsorption capacity and Foster swelling) measurement were performed in order to evaluate the performance of the adsorbents. The Foster swelling index and adsorption capacity of the DTAB modified calcium bentonite in the organic solvents follow the trend: xylene > ethylbenzene > toluene > gasoline > dual purpose kerosene (DPK) > diesel > water. However, the adsorption capacity of the adsorbent in diesel outweighed the adsorption capacity in DPK at high concentration of DTAB indicating that diesel has higher affinity for high DTAB concentration than DPK. The percentage removal of the solvent is directly proportional to the concentration of DTAB used in modifying the bentonite as well as the contact time between the adsorbent and the solvent, hence modified calcium bentonite adsorbed a higher percentage of organic solvents than the unmodified calcium bentonite. The adsorption characteristics of both adsorbents improved remarkably after proper agitation of the organic solvents, the unmodified calcium bentonite however adsorbed more water than the modified bentonite. Data obtained from adsorption isotherm models confirms that Freundlich adsorption isotherm model was favored more than Langmuir adsorption isotherm model with the correlation factor (R2) of the former tending more towards unity. The adsorption of ethylbenzene using DTAB modified and unmodified calcium bentonites follow a pseudo second order kinetics mechanism, suggesting that the rate determining step of adsorption involves both the adsorbent and the organic solvent.

2021 ◽  
Vol 1 ◽  
pp. 80-87
Author(s):  
Neni Damajanti ◽  
Anwar Ma’ruf ◽  
Hanafi Khafid Nugraha

Zeolite as an adsorbent has been widely used. Zeolite activation was carried out to increase the absorption. This study aimed to determine the characteristics of the active zeolite and apply it as an adsorbent. The activation process was carried out by adding acid and calcining at 4500C for 6 hours. Remazol Yellow FG is a dye that is widely used in the textile industry. In this study, the adsorption process was carried out on the Remazol Yellow FG solution, then analyzed the effect of changes in pH (5, 6, 7, 8, 9), contact time (30, 60, 90, 120, 150 minutes) and the concentration of Remazol Yellow FG solution ( 50, 100, 150, 200, 250 ppm) on the adsorption of Remazol Yellow FG dye. From the analysis of the sample solution of Remazol Yellow, the values of Ce and qe can be calculated. These values were then used to calculate KL and KF in the Langmuir adsorption isotherm and Freundlich adsorption isotherm models. From the experimental results, it could be seen that as the contact time increased, the adsorption capacity would be greater. However, when the zeolite was already in the saturated phase, the adsorption capacity would tend to decrease. In the Langmuir adsorption isotherm, the KL value was 0.0274 L/mg and in the Freundlich adsorption isotherm model, the KF value was 29.25 L/mg. Remazol Yellow FG adsorption tended to follow the Langmuir adsorption isotherm model with an R2 value of 0.998.


2022 ◽  
Vol 1212 (1) ◽  
pp. 012019
Author(s):  
I Syauqiah ◽  
D Nurandini ◽  
N P Prihatini ◽  
Jamiyaturrasidah

Abstract The process of manufacturing Sasirangan - a traditional fabric of South Kalimantan - has an impact that affects environmental pollution, namely the dyeing process of the fabric. The synthetic dyes used contain heavy metals and one of those toxic metals is copper (Cu). This study aims to determine the adsorption capacity of rice husk activated carbon adsorbent by adjusting the adsorption pattern based on isotherm models as the treatment to sasirangan liquid waste. The method consists of three stages: preparation of adsorbent by carbonization process, chemical and physical activation, then continued by adsorption process of Cu metal with carbon from rice husks with variations of adsorbent dose (2, 4, and 6 grams). This treatment was conducted by batch process. In this reseach, the adsorption capacity of rice husk adsorbent towards heavy metal Cu in sasirangan liquid waste was determined from the equilibrium state with the Langmuir isotherm equation and Freundlich isotherm equation. Based on isothermal studies of adsorption data, the correlation coefficient values obtained from the isotherm model approaches are: for dose of 2 grams adsorbent, Langmuir R2 = 0.9991 and Freundlich R2 = 0.9981; for dose of 4 grams adsorbent, Langmuir R2 = 0.9992 and Freundlich R2 = 0.9989; for dose of 6 grams adsorbent, Langmuir R2 = 0.9990 and Freundlich R2 = 0.9986. The results of investigation indicate that adsorption data correlated well with Langmuir isotherm model.


2018 ◽  
Vol 17 (05) ◽  
pp. 1850002 ◽  
Author(s):  
M. Ruthiraan ◽  
E. C. Abdullah ◽  
N. M. Mubarak ◽  
Sabzoi Nizamuddin

Wastewater discharge from textile industries contribute much to water pollution and threaten the aqua ecosystem balance. Synthesis of agriculture waste based adsorbent is a smart move toward overcoming the critical environmental issues as well as a good waste management process implied. This research work describes the adsorption of methylene blue dye from aqueous solution on nickel oxide attached magnetic biochar derived from mangosteen peel. A series of characterization methods was employed such as FTIR, FESEM analysis and BET surface area analyzer to understand the adsorbent behavior produced at a heating temperature of 800[Formula: see text]C for 20[Formula: see text]min duration. The adsorbate pH value was varied to investigate the adsorption kinetic trend and the isotherm models were developed by determining the equilibrium adsorption capacity at varied adsorbate initial concentration. Equilibrium adsorption isotherm models were measured for single component system and the calculated data were analyzed by using Langmuir, Freundlich, Tempkin and Dubinin–Radushkevich isotherm equations. The Langmuir, Freundlich and Tempkin isotherm model exhibit a promising R2-correlation value of more than 0.95 for all three isotherm models. The Langmuir isotherm model reflectsan equilibrium adsorption capacity of 22.883[Formula: see text]mg[Formula: see text]g[Formula: see text].


2012 ◽  
Vol 229-231 ◽  
pp. 100-104 ◽  
Author(s):  
Yun Fei Shi ◽  
Xiang Jun Liu ◽  
Hui Jiao Nie ◽  
Yin Shu Liu

The adsorption isotherm model of water vapor on activated alumina is an essential equation in designing the performance of adsorption. In this paper, the currently existed 14 isotherm models of water adsorption are summarized. The correlations among these models are analyzed. These isotherm models are evaluated by fitting the water adsorption data on Rhone-Poulenc activated alumina. The results show that AD-Toth, AD-LRC, AD-UNILAN and DMAP can fit the experimental data well.


2020 ◽  
Vol 2020 ◽  
pp. 1-11 ◽  
Author(s):  
Thuy Chinh Nguyen ◽  
Trang Do Mai Tran ◽  
Van Bay Dao ◽  
Quoc-Trung Vu ◽  
Trinh Duy Nguyen ◽  
...  

This paper presents the characteristics of fly ash which was modified by 2-mercaptobenzothiazole (MBT) and sodium dodecyl sulfate (SDS) as the surfactants after treating with 1M NaOH solution. The change in morphology, specific surface area, crystal structure, and composition of the unmodified and modified fly ash was evaluated by FTIR, XRD, FESEM, BET, and EDX methods and techniques. The FTIR spectra of modified fly ash showed that there was no chemical reaction between the surfactants and fly ash. The XRD patterns and FESEM images indicated that modified fly ash had zeolite structure with a pore size of about 50 nm. Heavy metal ion adsorption behavior as well as adsorption isotherm models (Langmuir and Freundlich) of Cd2+ and Hg2+ ions of the unmodified and modified fly ash were also investigated and discussed. The amount of adsorbed ions of the modified fly ash was higher than that of the unmodified fly ash. The calculated results from the adsorption data according to the adsorption isotherm models of the above ions displayed that the Langmuir isotherm model was complied for the Cd2+ adsorption process while the Freundlich isotherm model was fitted for the Hg2+ adsorption process.


2011 ◽  
Vol 11 (1) ◽  
pp. 96-102 ◽  
Author(s):  
Sunardi Sunardi ◽  
Utami Irawati ◽  
Yateman Arryanto ◽  
Sutarno Sutarno

Synthesis of surfactant modified kaolin from natural kaolin from Tatakan, Tapin, South Kalimantan and its application for carrier material of gibberellic acid have been conducted. The kaolin modification was done by surface engineering using cationic surfactant cetyltrimethylammonium bromide (C16TMABr). The characterizations of kaolin and surfactant modified kaolin were carried out by XRF, SEM, XRD, FTIR and TGA/DTA. The adsorption capacity of kaolin was determined by Langmuir adsorption isotherm model. The result showed that kaolin from Tatakan, South Kalimantan consist of kaolinite, halloysite, quartz, chlorite, and christobalite. Surface modification using cationic surfactant showed that increasing surfactant content onto kaolin was proportional to the amount of surfactant loaded. Gibberellic acid was partitioned into the organic phase created by the surfactant tails of the C16TMA+ modified kaolin. The calculations result by Langmuir adsorption isotherm model showed that the highest increasing adsorption capacity occurred on surfactant modified kaolin with surfactant/CEC ratio of 2.0, with the adsorption capacity of 28.41 mg/g.


2010 ◽  
Vol 10 (3) ◽  
pp. 320-326 ◽  
Author(s):  
Sunardi Sunardi ◽  
Yateman Yateman Arryanto ◽  
Sutarno Sutarno

Preparation, activation and adsorption study of natural kaolin from Tatakan, Tapin, South Kalimantan have been conducted. The activation of kaolin was done using 6 M HCl solutions at 90 °C for 3 h. The characterizations of kaolin were carried out by Fourier Transform Infrared, X-ray diffraction, and surface area analyzer. Adsorption parameters studied included the effect of pH, contact time, and concentration of gibberellic acid (GA3) onto kaolin samples. The amount of gibberellic acid adsorbed was determined using UV spectrophotometer. The adsorption capacity of kaolin was determined by Langmuir adsorption isotherm model. The result showed that activation of kaolin was resulted the larger specific surface area and more homogeneous composition of kaolin without any destruction of kaolin structure. Adsorption of gibberellic acid onto kaolin before and after activation showed that optimal adsorption was obtained at pH » 7 and reached the equilibrium within 4 h. The calculations result by Langmuir adsorption isotherm model showed that the increasing of adsorption capacity of acid activated kaolin is about 35%.


2003 ◽  
Vol 47 (9) ◽  
pp. 143-150 ◽  
Author(s):  
M.S. Alhakawati ◽  
C.J. Banks ◽  
D. Smallman

Previous studies have shown that Rhizopus oryzae strain IM 057412 grown in reticulated polyurethane foam demonstrated the same heavy metal adsorption capacity as the free biomass. Immobilisation in other types of polymers was shown to reduce the biomass uptake capacity because of mass transfer limitations due to the restricted porosity of the immobilisation matrices. For practical purposes the growing of biomass in polyurethane support particles to use as a commercial adsorbent is not viable or financially sound. The current work describes a different approach in which dried non-viable cells of R. Oryzae were incorporated into two types of polyurethane carrier matrix during the production process. The polymers used were a conventional hydrophobic polyurethane and a hydrophilic polyurethane, Hypol 2002. Oven-dried and powdered particles (D<150 μm) of R. oryazea were immobilised by mixing the biomass with each of the polymers prior to the reaction in which the polymer was expanded to form a foam: consequently the biomass was uniformly dispersed throughout the porous matrix. The resulting fungi-polyurethane matrices were then cut into cubes (≡4-5 mm dimension) and their adsorptive properties studied with respect to copper. Experiments were conducted in shake flasks to establish the equilibrium time for the reaction for both free and immobilised biomass. The biomass immobilised in Hypol gave the same adsorptive capacity as that of free biomass when compared on a weight basis, but biomass immobilised in conventional polyurethane foam showed no adsorption. To assess fully the effect of pH on copper and to eliminate precipitation as a removal mechanism experiments were conducted at different pHs and different copper concentrations. In each case the solution pH was maintained by acid or base addition in response to measurements using a standard calomel electrode. It was shown that at pH 5 copper concentrations above 100 mg l−1 were likely to precipitate. The amount of precipitation was accounted for within the high concentration adsorption isotherm experiments by using a mass balance approach. Results showed that the adsorption of the Hypol immobilised biomass followed the Langmuir adsorption isotherm model and showed the copper adsorption capacity of the matrix to be between 10 and 13 mg g−1. The copper attached to the immobilised biomass could easily be desorbed by increasing the acidity, allowing the matrix to be used in repetitive sorption-desorption cycles. There was a small decrease in the adsorption capacity after the first desorption cycle that could be explained by a partial loss of biomass as detected by loss of total organic carbon (TOC).


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