scholarly journals Investigation of sorption of 2,4-dichlorophenol on special hungarian oil shale

2018 ◽  
Vol 12 (1) ◽  
pp. 20-29
Author(s):  
Rauch Renáta ◽  
Rita Földényi

The development of efficient methods for the removal of different type of organic contaminates of natural waters is an ever challenging task in the modern environmental technology. The paper reports the physical characterization and adsorption properties of a Hungarian oil shale. Static equilibrium experiments were carried out to study the adsorption of 2,4-dichlorophenol from aqueous solution. The obtained equilibrium data were satisfactorily fitted by a multistep adsorption isotherm within the concentration range of 0 to 100 mg/l. According to our laboratory scale experiments the studied adsorbent immobilizes the contaminants more efficiently than a number of other adsorbents applied in different remediation technologies. More than 90 % of the added 2,4-dichlorophenol was adsorbed by the studied oil shale. The contaminants are bound strongly by the sorbent therefore they cannot be washed out by the groundwater flow which, in turn, favors to the natural bacterial decomposition process of the polluting compound. This is considered as a significant advantage of the adsorbent because no chemical regeneration of the inexpensive oil shale is required. The reported results indicate that the oil shale can be used efficiently for the treatment of natural waters to remove their organic contaminants.

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Johnatan D. Castro-Castro ◽  
Iván F. Macías-Quiroga ◽  
Gloria I. Giraldo-Gómez ◽  
Nancy R. Sanabria-González

Clay minerals can be modified organically by a cationic surfactant resulting in materials known as organoclays. The organoclays have been used as adsorbents of most of the organic contaminants in the aqueous solution and oxyanions of the heavy metal. In this study, a Colombian bentonite was modified with hexadecyltrimethylammonium bromide to obtain an organobentonite, and its capacity to adsorb Cr(VI) oxyanions in the aqueous solution was evaluated. The effect of pH, stirring speed, adsorbent amount, contact time, and ionic strength were investigated at 25°C. Stirring speeds above 200 rpm, contact times greater than 120 min, and the addition of NaCl (0.1 to 2.0 mM) did not have a significant effect on Cr(VI) removal. The influence of the adsorbent amount and pH on Cr(VI) adsorption was studied by the response surface methodology (RSM) approach based on a complete factorial design 32. Results proved that the Cr(VI) adsorption follows a quadratic model with high values of coefficient of determination (R2 = 95.1% and adjusted R2 = 93.9%). The optimal conditions for removal of Cr(VI) from an aqueous solution of 50 mg/L were pH of 3.4 and 0.44 g amount of the adsorbent. The adsorption isotherm data were fitted to the Langmuir and Freundlich adsorption isotherm models, and the model parameters were evaluated. The maximum adsorption capacity of Cr(VI) onto organobentonite calculated from the Langmuir model equation was 10.04 ± 0.34 mg/g at 25°C. The results suggest that organobentonite is an effective adsorbent for Cr(VI) removal, with the advantage of being a low-cost material.


2013 ◽  
Vol 295-298 ◽  
pp. 1154-1160 ◽  
Author(s):  
Guo Zhi Deng ◽  
Xue Yuan Wang ◽  
Xian Yang Shi ◽  
Qian Qian Hong

The objective of this paper is to investigate the feasibility of phenol adsorption from aqueous solution by Pinus massoniana biochar. Adsorption conditions, including contact time, initial phenol concentration, adsorbent dosage, strength of salt ions and pH, have been investigated by batch experiments. Equilibrium can be reached in 24 h for phenol from 50 to 250 mg• L-1. The optimum pH value for this kind of biochar is 5.0. The amount of phenol adsorbed per unit decreases with the increase in adsorbent dosage. The existence of salt ions makes negligible influence on the equilibrium adsorption capacity. The experimental data is analyzed by the Freundlich and Langmuir isotherm models. Equilibrium data fits well to the Freundlich model. Adsorption kinetics models are deduced and the pseudo-second-order kinetic model provides a good correlation for the adsorbent process. The results show that the Pinus massoniana biochar can be utilized as an effective adsorption material for the removal of phenol from aqueous solution.


2011 ◽  
Vol 356-360 ◽  
pp. 537-546
Author(s):  
Yow Loo Au Yoong ◽  
Pei Lay Yap ◽  
Muralithran G. Kutty ◽  
Olaf Timpe ◽  
Malte Behrens ◽  
...  

The use of surface oxidized covellite (CuS), namely mixed phase copper sulphide (CuS and CuSO4) was studied for the removal of mercury from aqueous solution under the effect of various reaction parameters (pH, time, Hg(II) concentration). From batch sorption studies, the equilibrium data revealed that the sorption behaviour of Hg(II) onto mixed phase copper sulphide follows well with Langmuir isotherm and the maximum sorption capacity (Qmax) determined ≈ 400mg Hg(II) /g of sorbent. Meanwhile, all the unreacted and reacted mixed phase copper sulphides were also characterized by Powder XRD, SEM and XPS techniques. The results indicated that the sorption of Hg(II) onto mixed phase copper sulphide occurs initially through the dissolution of surface oxidized CuSO4layer. After that, the surface complexation product formed and sorbed onto the surface of CuS. These outcomes suggest the potential ability of CuS in removing Hg(II) even if the CuS layer is being surrounded by oxidized layer of CuSO4.


2011 ◽  
Vol 197-198 ◽  
pp. 131-135
Author(s):  
Li Fang Zhang ◽  
Ying Ying Chen ◽  
Wen Jie Zhang

Biosorption of chromium (VI) ions from aqueous solution with fungal biomass Penicillium sp. was investigated in the batch system. The influence of contact time, solution pH, biosorbent concentration, initial concentration of Cr (VI) ions and temperature on biosorption capacity of Cr (VI) ions was studied. The uptake of Cr (VI) was highly pH dependent and the optimum pH for biosorption of Cr (VI) ions was found to be 2.0. Biosorption capacity of Cr (VI) ions decreased with increased biosorbent concentration and increased with increase in initial concentration of Cr (VI) ions. The experiment results also showed that high temperatures increased the biosorption capacity of Cr (VI) by fungal biomass. It was found that the biosorption equilibrium data were fitted very well to the kangmuir as well as to the Freundlich adsorption model. The maximum sorptive capacities obtained from the Langmuir equation at temperature of 20, 30 and 40°C were 25.91, 32.68 and 35.97 mg/g for Cr (VI) ions, respectively. The results of this study indicated that the fungal biomass of Penicillium sp. is a promising biosorbent for removal of chromium (VI) ions from the water.


2017 ◽  
Vol 29 (1) ◽  
pp. 9-13
Author(s):  
Masuma Sultana Ripa ◽  
Rafat Mahmood ◽  
Sabrina Khan ◽  
Easir A Khan

Adsorption separation of phenol from aqueous solution using activated carbon was investigated in this work. The adsorbent was prepared from coconut shell and activated by physical activation method. The coconut shell was first carbonized at 800°C under nitrogen atmosphere and activated by CO2 at the same temperature for one hour. The prepared activated carbon was characterized by Scanning Electron Microscope (SEM) and BET Surface Analyzer and by the determination of iodine number as well as Boehm titration. The iodine number indicates the degree of relative activation of the adsorbent. The equilibrium adsorption isotherm phenol from aqueous solution was performed using liquid phase batch adsorption experiments. The effect of experimental parameters including solution pH, agitation time, particle size, temperature and initial concentration was investigated. The equilibrium data was analyzed using Langmuir and Freundlich adsorption model to describe the adsorption isotherm and estimate the adsorption isotherm parameters. The results indicate the potential use of the adsorbent for removal of phenol from the aqueous solution.Journal of Chemical Engineering, Vol. 29, No. 1, 2017: 9-13


2021 ◽  
Vol 10 (1) ◽  
pp. 59-66
Author(s):  
Son Le Lam ◽  
Phu Nguyen Vinh ◽  
Hieu Le Trung ◽  
Tan Le Thua ◽  
Nhan Dang Thi Thanh ◽  
...  

Glucomannan/graphene oxide (GM/GO) hydrogel was synthesized by using calcium hydroxide as the crosslinker. The synthesized material was characterized by using IR, XRD, SEM, EDX and RAMAN technology. The composite hydrogel was used for removal of organic dyes from aqueous solution. The results showed that the GM/GO hydrogel had a porous structure and a high adsorption capacity toward methylene blue (MB). The pseudo-second-order kinetic model could fit the rate equation of MB adsorption onto the GM/GO hydrogel. The adsorption of MB onto GM/GO hydrogel was a spontaneous process. In addition, the equilibrium adsorption isotherm data indicated that equilibrium data were fitted to the Langmuir isotherm and the maximum dye adsorption capacity was 198,69 mg.g-1. Moreover, the hydrogel was stable and easily recovered and adsorption capacity was around 97% of the initial saturation adsorption capacity after being used five times.


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