scholarly journals Polyaspartate-Ionene/Na+-Montmorillonite Nanocomposites as Novel Adsorbent for Anionic Dye; Effect of Ionene Structure

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2843
Author(s):  
Hany El-Hamshary ◽  
Abeer S. Elsherbiny ◽  
Mohamed H. El-Newehy ◽  
Mohamed E. EL-Hefnawy

Surface modification of sodium montmorillonite (Na+-Mt) was performed using antimicrobial agents to produce an ecofriendly nanocomposite. The adsorption performance of the nanocomposite has been evaluated for the removal of Acid Blue 25 dye (AB25) as a model organic pollutant from wastewater. Sodium montmorillonite (Na+-Mt) was modified with three different ionene compounds through ion exchange, and further modified through reaction with polyaspartate to provide three ecofriendly nanocomposites (denoted ICP-1–3). The nanocomposites were characterized using FTIR, PXRD, TEM, SEM, and BET surface area. The adsorption isotherm of AB25 onto ICP-1, ICP-2 and ICP-3 was analyzed using the Langmuir, Freundlich, and Dubinin–Radushkevich (D–R) models. The adsorption isotherm was found to be best fitted by a Freundlich model. The thermodynamic parameters were calculated. The kinetics of the adsorption data were analyzed and the adsorption behavior was found to obey pseudo-second-order kinetics, and the intraparticle diffusion model. The adsorption mechanism was studied by FTIR.

2018 ◽  
Vol 20 (2) ◽  
pp. 408-416

Mesophilic biomass and thermophilic biomass samples were isolated and used to remove Dorasyn Red dye from aqueous solutions. The biosorption kinetics of dye uptake by four different types of biomass at three temperatures (20, 30, and 40 °C) were investigated using pseudo-first order kinetics, pseudo-second order kinetics, intraparticle diffusion, Elovich, and Bangham models. The pseudo-second-order kinetics model and the first stage of the intraparticle diffusion model were effective in describing the experimental kinetics data. The biosorption results showed that the mesophilic biomass samples could be useful for removing dye under acidic conditions.


2020 ◽  
Vol 81 (10) ◽  
pp. 2270-2280
Author(s):  
Yonggang Xu ◽  
Tianxia Bai ◽  
Yubo Yan ◽  
Yunfeng Zhao ◽  
Ling Yuan ◽  
...  

Abstract It is of great significance to remove Cr(VI) from water as a result of its high toxicity. Biochar from corn straw was modified by different acids (HNO3, H2SO4 and H3PO4) to remove Cr(VI) from aqueous solution. To estimate the removal mechanisms of Cr(VI) by the acid-modified biochars, batch experiments were performed in the light of contact time, Cr(VI) concentration, and pH, and the characteristics of acid-modified biochars before and after Cr(VI) adsorption were investigated by Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS). The adsorption kinetics of Cr(VI) by acid-modified biochars were consistent with the pseudo-second-order model, and the adsorption isotherm obeyed the Freundlich model. Furthermore, the acid- modified biochars could supply more oxygen-containing functional groups (-COOH and -OH) as electron donor (e−) and hydrogen ion (H+) to enhance the reduction of Cr(VI) to Cr(III), resulting in enhanced removal of Cr(VI). HNO3-modified biochar exhibited the highest removal efficiency of Cr(VI). In general, the acid modifition of biochar was an effective method to increase the removal of Cr(VI).


2017 ◽  
Vol 49 (4) ◽  
pp. 419-429
Author(s):  
Natasa Jovic-Jovicic ◽  
Predrag Bankovic ◽  
Zorica Mojovic ◽  
Bojana Nedic-Vasiljevic ◽  
Sanja Marinovic ◽  
...  

The bio-nanocomposite of montmorillonite and natural biopolymer chitosan (C-MM) was synthesized. Intercalation of chitosan in form of monolayer into the interlamellar space of montmorillonite was confirmed by XRD and IR analysis. The adsorption of textile dyes: Acid Yellow 99 (AY99), Acid Orange 10 (AO10) and Reactive Black 5 (RB5) onto C-MM was investigated. The adsorption was performed with the respect to adsorption time, pH and initial dye concentration. The kinetics of adsorption obeyed pseudo-second-order of kinetics and was the most efficient in acidic pH. Langmuir model best described the adsorption of AY99 and AO10 , while RB5 adsorption isotherm was best fitted with Freundlich model.


2013 ◽  
Vol 2013 ◽  
pp. 1-5
Author(s):  
A. A. Kale

Fundamental investigation on the removal of heavy metal Pb2+ from aqueous solutions by sulphonated biomass (S-III) of Cicer arietinum is conducted in batch mode. The effect of different parameters such as contact time, sorbent dose, pH and temperature has been studied. Adsorption kinetic modeling data were found. The kinetics of biosorption results shows that sorption process is well explained by pseudo-second-order model with determination coefficients 0.998 for S-III under all experimental conditions. The sorption mechanism was determined by Weber and Morris intraparticle diffusion model. Thermodynamic parameters, namely, KD and ΔG,have also been calculated to determine the spontaneity of the process.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Hamid Ziyat ◽  
Mohammed Naciri Bennani ◽  
Hassan Hajjaj ◽  
Omar Qabaqous ◽  
Said Arhzaf ◽  
...  

The present work aims to study the affinity of a component of the thyme essential oil “thymol” to natural Moroccan clay “Rhassoul” using the adsorption technique. The physicochemical characterizations of the purified and modified clay were carried out by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), DTA/TGA, and SEM-EDX. Thymol adsorption tests on the purified Rhassoul (Rh-P) and the modified one by CTAB (Rh-CTAB) were followed by UV-visible spectroscopy. They show that the adsorption isotherms can be described by the Freundlich model and that the kinetics of adsorption is in accordance with the pseudo-second-order model for the two clays. Adsorption capacities obtained were of the order of 6 mg/g for the purified Rhassoul and 16 mg/g for the modified Rhassoul by cetyltrimethylammonium bromide (CTAB). These values show that the modified Rhassoul has a better adsorption capacity compared to the purified Rhassoul.


2013 ◽  
Vol 726-731 ◽  
pp. 733-738 ◽  
Author(s):  
Ling Die Meng ◽  
Min Wu ◽  
Ye Tian ◽  
Shigenori Kuga ◽  
Yong Huang

This work reports a cationic modified cellulose hydrogel for fluoride and arsenic adsorption. This adsorbent had a high efficiency in removal of F-, AsO2- and AsO43- simultaneously from aqueous solutions, even at low initial concentrations. Adsorption kinetics showed the relatively rapid rate to reach equilibrium, as could be explained by the pseudo-second-order model and the intraparticle diffusion model within 20 min before the equilibrium. Freundlich model could fit the adsorption process best, and the results showed the improved arsenic adsorption performances especially for AsO43-, much larger than other reported absorbents.


2021 ◽  
Vol 15 (3) ◽  
pp. 377-388
Author(s):  
Sadek Chentouf ◽  
◽  
Smail Kacha ◽  
Réda Marouf ◽  
Fouad Mekhalef Benhafsa ◽  
...  

Synthesis, characterization and application of the polyaniline-diatomite (PAD) composite in the adsorption of Reactive Red 120 (RR 120) and Acid Blue (AB) dyes were carried out. The composite was prepared by the in situ polymerization of aniline. Mass of purified diatomite was mixed with a solution containing aniline dissolved in 2M hydrochloric acid at room temperature. The solid obtained was characterized using the SEM, XRD and FTIR analyses. The kinetic adsorption of dyes was described using the pseudo-second order kinetic model. The adsorption isotherm of the RR 120 dye can be fitted by the Freundlich adsorption isotherm model. However, the adsorption isotherm of the AB dye can be better fitted by the BET model.


2018 ◽  
Vol 77 (9) ◽  
pp. 2327-2340 ◽  
Author(s):  
Jianrui Niu ◽  
Xiuxiu Jia ◽  
Yaqing Zhao ◽  
Yanfang Liu ◽  
Weizhang Zhong ◽  
...  

Abstract The CeO2@ZSM-5 was prepared by the dipping method. We used ZSM-5 and CeO2 as the carrier and load components, respectively. The aim was to reduce the low concentration of Cr(VI) in simulated wastewater (the concentration of Cr(VI) ranged from 0.2 to 1 mg/L). The characteristics of ZSM-5 and CeO2@ZSM-5 samples were determined by X-ray powder diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and Brunauer–Emmett–Teller (BET). Characterization results showed that the particle size, BET surface area and pore volume for CeO2@ZSM-5 was around 0.783 nm, 421.307 m2/g and 0.313 m3/g, respectively. In addition, the optimum conditions were obtained by the orthogonal test, and the details were as follows: optimal pH, adsorbent dose, initial concentration of Cr(VI) and equilibrium time were 3, 5 g/L, 0.6 mg/L and 70 min respectively. The removal of Cr(VI) was 99.56% in these conditions. The pseudo-second-order model best described the adsorption kinetics of Cr(VI) onto CeO2@ZSM-5. Isotherm data were treated according to Langmuir, Freundlich and Temkin isotherm models. The results showed that the Freundlich adsorption isotherm model fitted best in the temperature range studied. Adsorption capacity increased with temperature, showing the endothermic nature of Cr(VI) adsorption. The desorption results showed the best recovery of Cr(VI) using 0.1 M HCl.


2021 ◽  
Vol 37 (1) ◽  
pp. 128-135
Author(s):  
Vijay Laxman Gurav ◽  
Rajesh Ashok Samant

In the present work, we studied the impact of adsorption parameters on adsorption of M (II) [Cadmium and Lead] using calcinated chicken egg shell as biomaterial. The characterization of biomaterial reveals; crystallite size by Scherrer formula is 66.58 nm and 9.80 m2/g BET surface area. The adsorption of cadmium and lead on calcinated egg shell was found to be dependent on equilibrium adsorption parameters. The adsorption kinetic models and adsorption isotherm were successfully applied. The removal method was validated with anodic stripping voltametric technique. For standard aqueous sample of M (II), maximum removals were obtained at pH 5 and 200 mg of adsorbent and 120 minutes of contact time. The kinetic model followed pseudo second order kinetics at equilibrium contact time of 120 minute. The amounts of M (II) adsorbed per unit mass of calcinated egg shell increases with initial concentration up to 50 mg/L followed by deviation in results were observed. The Freundlich’s adsorption isotherm model is better fitted for M (II) adsorption with R2 closed to unity i.e0.9998 for Cadmium and 0.9983 for Lead. For real samples, adsorbed M (II) also recovered with 98 + 0.5 % recovery using 10 ml of 1.0 M HCl with flow rate of 2 ml per minute.


2018 ◽  
Vol 16 (5) ◽  
pp. 814-826
Author(s):  
Xiaowei Liu ◽  
Lihui Huang ◽  
Lisha Wang ◽  
Chuang Wang ◽  
Xueyuan Wu ◽  
...  

Abstract Activated carbon (AC) was prepared from Platanus orientalis leaves by H3PO4 activation using a microwave heating method and characterized by SEM (scanning electron microscopy), Brunauer-Emmett-Teller (BET) surface area analysis and FTIR (Fourier transform infrared spectroscopy) techniques. AC exhibited a surface area of 1089.67 m2/g and a relatively high pore volume of 1.468 cm3/g. Utilization of AC for the removal of Cr(VI) from aqueous solution was researched. The adsorption efficiency was highly pH dependent and adsorption capacity of AC for Cr(VI) could reach up to 135.24 mg/g. Adsorption equilibrium could be quickly reached within 2 h. A kinetic study indicated that the adsorption of Cr(VI) conformed to the pseudo-second-order model (R2 > 0.99). An intraparticle diffusion model was applied to describe the adsorption kinetics, and the results showed that there are other factors that affect the rate. Chemical regeneration for AC saturated with Cr(VI) was performed and HNO3 displayed the best regeneration performance among the four chemical regeneration agents (HNO3, H2SO4, NaOH, NaCl). The regeneration performance increased at first and then decreased with the rise of HNO3 concentration, and regeneration reaction could reach equilibrium within 4 h in the first cycle. The FTIR spectra revealed that HNO3 successfully introduced N-H bonds onto the AC surface in the regeneration process.


Sign in / Sign up

Export Citation Format

Share Document