scholarly journals The effect of alkaline pretreatment on surfactant-modified clinoptilolite for diclofenac adsorption: isotherm, kinetic, and thermodynamic studies

2020 ◽  
Author(s):  
Fateme Poorsharbaf Ghavi ◽  
Fereshteh Raouf ◽  
Ahmad Dadvand Koohi
Keyword(s):  
Ph Effect ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Thermodynamic Studies ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Modified Clinoptilolite ◽  
Kinetic And Thermodynamic Studies

Abstract The elimination of diclofenac traces from aqueous environments is important. In this research, the effect of alkaline (NaOH) pretreatment on clinoptilolite before its modification with a surfactant (HDTMA) for diclofenac adsorption under the speculation of the sole presence of diclofenac in the aqueous solution is investigated. The results are compared through isotherm, kinetic, and thermodynamic studies and supplemented by FTIR, SEM, BET, and the zeta potential analyses. The contact time was investigated in a 0–180-min range. The pH effect was studied in a range of 5–10 because of diclofenac dissociation below pH = 5. The effect of the temperature on diclofenac adsorption was also considered by establishing the experiments at 25, 35, and 45 °C. For HDTMA-modified clinoptilolite, Temkin, and for NaOH-HDTMA-modified clinoptilolite, Dubinin–Radushkevich, and Freundlich isotherm models and in both cases, the pseudo-second-order kinetic model fitted the experimental data best. All the enthalpy and the entropy changes were negative, suggesting exothermic adsorption with a decrease in the degree of freedom of diclofenac anions after the adsorption. Furthermore, diclofenac physisorption was confirmed through isotherm and kinetic studies.

scholarly journals Parametric, equilibrium and kinetic studies on the removal of mercury using ion exchange resin

2017 ◽  
Vol 12 (2) ◽  
pp. 305-313 ◽  
Author(s):  
N. Rajamohan ◽  
M. Rajasimman
Keyword(s):  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Strong Acid ◽  
Ion Exchange Resin ◽  
Second Order ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Acid Cation ◽  
Pseudo Second Order ◽  
Langmuir Constants

This experimental research was an investigation into removal of mercury by using a strong acid cation resin, 001 × 7. Parametric experiments were conducted to determine the optimum pH, resin dosage, agitation speed and the effect of change in concentration in the range of 50–200 mg/L. High resin dosages favoured better removal efficiency but resulted in lower uptakes. Equilibrium experiments were performed and fitted to Langmuir and Freundlich isotherm models. Langmuir model suited well to this study confirming the homogeneity of the resin surface. The Langmuir constants were estimated as qmax = 110.619 mg/g and KL = 0.070 L/g at 308 K. Kinetic experiments were modeled using Pseudo second order model and higher values of R2 (>0.97) were obtained. The Pseudo second order kinetic constants, namely, equilibrium uptake (qe) and rate constant (k2), were evaluated as 59.17 mg/g and 40.2 × 10−4 g mg−1 min−1 at an initial mercury concentration of 100 mg/L and temperature of 308 K.

scholarly journals Comparative Study of Ni-Zn LHS and Mg-Al LDH Adsorbents of Navy Blue and Yellow F3G Dye

2018 ◽  
Vol 16 (1) ◽  
pp. 36 ◽  
Author(s):  
Idha Yulia Ikhsani ◽  
Sri Juari Santosa ◽  
Bambang Rusdiarso
Keyword(s):  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Second Order ◽  
Isotherm Models ◽  
Disperse Dyes ◽  
Order Kinetic ◽  
Initial Ph ◽  
Isotherm Adsorption ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Adsorption of disperse dyes from wastewater onto Ni-Zn LHS (layered hydroxide salts) and Mg-Al LDH (layered double hydroxides) has been compared in this study. Effects of initial pH solution, contact time and initial dye concentration were investigated. The ability of the adsorbent to be reused was also studied. The results showed that acidic condition was favorable for the adsorption of each dyes onto both adsorbent. The adsorption kinetics was studied using pseudo-first-order, pseudo-second-order and Santosa’s kinetics models. The experimental data fits well with the pseudo-second order kinetic model. The equilibrium adsorption data were analyzed using Langmuir and Freundlich isotherm models. The results showed that adsorption of navy blue onto both adsorbent followed Freundlich isotherm adsorption, while yellow F3G followed Langmuir isotherm adsorption. In the application for the adsorption the wastewater containing dyes, Ni-Zn LHS has a better adsorption capacity of 52.33 mg/g than that of Mg-Al LDH that 30.54 mg/g. Calcination of the adsorbent which has already been used increased the adsorption capacity of Mg-Al LDH to 84.75 mg/g, but decreased the adsorption capacity of the Ni-Zn LHS to 42.65 mg/g.

scholarly journals Removal of Acidic Dye from Aqueous Solution Using Surfactant Modified Bentonite (Organoclay): Batch and Kinetic Study

2020 ◽  
Vol 26 (5) ◽  
pp. 64-81
Author(s):  
Saraa M. Ibrahim ◽  
Ziad T. Abd Ali
Keyword(s):  
Aqueous Solution ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Ammonium Bromide ◽  
Order Kinetic ◽  
Sorption Data ◽  
Modified Bentonite ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Cetyltrimethyl Ammonium

Modified bentonite has been used as effective sorbent material for the removal of acidic dye (methyl orange) from aqueous solution in batch system. The natural bentonite has been modified using cationic surfactant (cetyltrimethyl ammonium bromide) in order to obtain an efficient sorbent through converting the properties of bentonite from hydrophilic to organophilic. The characteristics of the natural and modified bentonite were examined through several analyses such as Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Surface area. The batch study was provided the maximum dye removal efficiency of 88.75 % with a sorption capacity of 555.56 mg/g at specified conditions (150 min, pH= 2, 250 rpm, and 0.5 g/100 ml). The-results-showed that with the Freundlich isotherm model the sorption data was accurately described with (R2≥0.94) in comparison with the Langmuir model under the studied conditions. The kinetic studies were revealed that the sorption follows a pseudo-second-order kinetic model which indicates chemisorption between sorbent and sorbate molecules. 

scholarly journals Equilibrium and kinetic studies of sorption of 2.4-dichlorophenol onto 2 mixtures: bamboo biochar plus calcium sulphate (BC) and hydroxyapatite plus bamboo biochar plus calcium sulphate (HBC), in a fluidized bed circulation column

2016 ◽  
Vol 18 (2) ◽  
pp. 59-67 ◽  
Author(s):  
Ahmed Hassan Alamin ◽  
Lupong Kaewsichan
Keyword(s):  
Fluidized Bed ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Calcium Sulphate ◽  
Isotherm Models ◽  
Process Time ◽  
Order Kinetic ◽  
Column Adsorption ◽  
Order Kinetic Model

Abstract Sorption studies were carried out to investigate removal of 2.4-dichlorophenol (2.4-DCP) from aqueous solution in a fluidized bed by two types of adsorbent mixtures: BC (Bamboo char plus Calcium sulphate), and HBC (Hydroxyapatite plus Bamboo char plus Calcium sulphate); both manufactured in ball shape. The main material bamboo char was characterized by FTIR, DTA and SEM. The adsorption experiments were conducted in a fluidized bed circulation column. Adsorption, isotherms and kinetic studies were established under 180 min operating process time, at different initial 2.4-DCP solution concentrations ranging from 5–10 mg/L, and at different flow rates ranging from 0.25–0.75 L/min. The data obtained fitted well for both the Langmuir and Freundlich isotherm models; indicating favorable condition of monolayer adsorption. The kinetics of both adsorbents complies with the pseudo second-order kinetic model. BC was proven a new effective composite and low cost adsorbent which can be applied in the field of wastewater treatment, and it can also play an important role in industry water treatment.

Biosorption of strontium ions from aqueous solution using modified eggshell materials

2017 ◽  
Vol 105 (12) ◽  
Author(s):  
Sayed S. Metwally ◽  
Hoda E. Rizk ◽  
Mona S. Gasser
Keyword(s):  
Aqueous Solution ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Sorption Process ◽  
Order Kinetic ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Biomass Materials ◽  
Strontium Ions

AbstractGreen composites emphasize renewable starting materials for better economy using biomass materials. Therefore, low-cost composite biosorbent was prepared by modification of eggshell material using heteropoly acid for removal of strontium ions from aqueous solution. The resulted composite was characterized and evaluated for the sorption process using the batch technique. Low concentration of strontium ions was used to evaluate the sorption sensitivity of the prepared composite. The obtained experimental results illustrated that the modification process of eggshell material enhanced the percent uptake from 49.9 to 95.7%. From kinetic studies, the sorption of strontium ions follows the pseudo-second-order kinetic model. The isotherm studies indicated that Langmuir is more applicable than Freundlich isotherm. Moreover, Dubinin–Radushkevich isotherm was studied. Thermodynamic studies revealed that the sorption process is spontaneous and has endothermic nature. Strontium ions can be desorbed from the modified eggshell using HNO

scholarly journals Kinetics and adsorption studies of lead (II) onto activated carbon using low cost adsorbents

2018 ◽  
Vol 20 (2) ◽  
pp. 381-388 ◽  
Keyword(s):  
Low Cost ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Rate Limiting Step ◽  
Bambusa Vulgaris ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Fagopyrum Esculentum Moench

The removal of Lead (II) from aqueous solutions using Fagopyrum esculentum Moench (Buckwheat) and Bambusa vulgaris (common bamboo) as adsorbents was investigated. The effects of various experimental parameters such as initial concentration, contact time and pH have been studied using batch adsorption technique. All the Adsorption isotherm models fitted well with the adsorption data. However, Freundlich isotherm displayed a better fitting model than the other two isotherm models due to high correlation coefficient (R2). This indicates the applicability of multilayer coverage of the Pb (II) on the surface of adsorbent. The adsorption kinetics was studied using four simplified models and it was found to follow the pseudo-second-order kinetic model which confirmed the applicability of the model. The adsorption mechanism was found to be chemisorption and the rate-limiting step was mainly surface adsorption.

Adsorption of As(V) from Aqueous Solution by the Fe(III)-Impregnated Sorbent Prepared from Sugarcane Bagasse and Applicability of Different Adsorption Models

2013 ◽  
Vol 316-317 ◽  
pp. 509-515
Author(s):  
Hua Zhang ◽  
Xue Hong Zhang ◽  
Yi Nian Zhu ◽  
Mei Na Liang ◽  
Rong Rong Lu
Keyword(s):  
Aqueous Solution ◽  
Sugarcane Bagasse ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorption Models ◽  
Adsorption Capacities ◽  
Monolayer Adsorption ◽  
Order Kinetic Model ◽  
Pseudo Second Order

In this study, a Fe(III)-impregnated sorbent was prepared from sugarcane bagasse and FeCl3 solution via carbonization/activation in a muffle furnace at 500 °C for 4h. Batch experiments were carried out to determine the capacity of the Fe(III)-impregnated sorbent to adsorb As(V) from aqueous solution. The dynamical data fitted very well with the pseudo-second-order kinetic model and the calculated adsorption capacities of 4.8263, 5.2219 and 7.1225 mg/g were equal to the actual values of the experiments at temperatures of 20, 25, and 35 °C, respectively. The experimental data were modeled by Langmuir and Freundlich isotherm models. The Langmuir isotherm with R2 values of 0.9926-0.9968 could yield better fits than the Freundlich isotherm, and the adsorption was endothermic, indicating monolayer adsorption of As(V).Freundlich isotherm, and the adsorption was endothermic, indicating monolayer adsorption of As(V).

Isothermal, Kinetic, and Thermodynamic Studies of Graphene Oxide Adsorption on Silk

2021 ◽  
Vol 8 (5) ◽  
pp. 18-29
Author(s):  
Arobindo Chatterjee ◽  
Vinit Kumar Jain
Keyword(s):  
Graphene Oxide ◽  
Freundlich Isotherm ◽  
Sorption Process ◽  
Order Kinetic ◽  
Solution Ph ◽  
Thermodynamic Studies ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Isothermal Kinetic ◽  
Kinetics Of

The properties of graphene enriched silk depend on the amount of graphene oxide (GO) adsorption on silk. GO dipping parameters include the GO solution pH, initial GO concentration, dipping time and temperature, and the type of substrate. The effects of GO dipping parameters on the sorption process are studied to achieve the maximum GO adsorption on the silk surface for the preparation of an economical graphene/silk-based textile product. In addition, equilibrium isotherms, kinetics, and thermodynamics of GO adsorption on the silk surface in a batch sorption process are examined to understand the adsorption mechanism. The Freundlich isotherm best describes the adsorption of GO onto the silk. A pseudo-second order kinetic model best describes the kinetics of GO adsorption. Thermodynamic studies reveal that GO adsorption is spontaneous and exothermic.

Sr(II) Removal from Aqueous Solution by Bacillus cereus Biomass, Equilibrium and Kinetic Studies

2011 ◽  
Vol 230-232 ◽  
pp. 1129-1132 ◽  
Author(s):  
Ya Li He ◽  
Tian Hai Wang ◽  
Jun Cao Shi
Keyword(s):  
Aqueous Solution ◽  
Bacillus Cereus ◽  
Practical Implication ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Order Kinetic Model ◽  
Economic Technology

Batch experiments were carried out to determine the capacity of Bacillus cereus biomass to adsorb Sr(II) ions from aqueous solution with respect to pH, initial Sr(II) concentration, contact time and biomass dose. The experimental data were modeled by Langmuir and Freundlich isotherm models. Langmuir model resulted in the best fit of the adsorption data. The maximum adsorption capacity for Sr(II) was 78.34 mg/g. The best correlation was provided by the second-order kinetic model, implying that chemical sorption was the rate-limiting step. The practical implication of this study is the development of an effective and economic technology for Sr(II) removal from contaminated waters.

Adsorption Characteristics of Phenol in Aqueous Solution by Pinus massoniana Biochar

2013 ◽  
Vol 295-298 ◽  
pp. 1154-1160 ◽  
Author(s):  
Guo Zhi Deng ◽  
Xue Yuan Wang ◽  
Xian Yang Shi ◽  
Qian Qian Hong
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Pinus Massoniana ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorbent Dosage ◽  
Salt Ions ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

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.

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