scholarly journals Novel chitosan and Laponite based nanocomposite for fast removal of Cd(II), methylene blue and Congo red from aqueous solution

e-Polymers ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 244-256
Author(s):  
Guobin Xu ◽  
Yuejun Zhu ◽  
Xiujun Wang ◽  
Shanshan Wang ◽  
Tianxiang Cheng ◽  
...  

AbstractA series of chitosan and Laponite based nano-composite adsorbents, which showed an excellent performance for fast and efficient removal of Cd(II), methylene blue (MB) and Congo red (CR) from aqueous solution, were prepared. In the adsorbent, with the increase of Laponite component, the surface area increased from 44.69 m2 g-1 to 64.58 m2 g-1. As a result, the adsorption rates were enhanced by increasing Laponite component. The adsorption capacities for Cd(II) and MB increased with increasing Laponite component due the cationic characteristic of two pollutants, and the opposite result was found for the removal of CR. The impacts of some factors, e.g. solution pH, temperature, pollutant concentration and salt, on the adsorption capacity were investigated. Additionally, this adsorbent could be effectively regenerated by dilute HCl solution after the adsorption of Cd(II), and the mixture of methanol and acetic acid was a suitable eluent after the adsorption of two dyes.

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Feng Zhang ◽  
Yue Yin ◽  
Chunlei Qiao ◽  
Ya-nan Luan ◽  
Mengyan Guo ◽  
...  

In this study, polypyrrole-modified red mud (PRM) was prepared for the efficient removal of anionic dyes (methyl orange and Congo red) from aqueous solutions. The phytotoxicity (bean sprouts) of the dye solution before and after dye removal was investigated. Adsorption kinetics confirmed that the adsorption of methyl orange (MO) and Congo red (CR) on PRM was controlled by chemical reactions between the functional groups of polypyrrole and dyes. From Langmuir isotherm fitting, we found the theoretical adsorption capacities of MO and CR on PRM were 194.1 and 314.9 mg/g, respectively. The adsorption progress of MO and CR on PRM was found to be spontaneous and endothermic. The column studies demonstrated that, under dynamic flow, the PRM can efficiently remove MO and CR from aqueous solution, with adsorption capacities of 31.08 and 55.04 mg/g, respectively. In the toxicity test, the phytotoxicity of the column effluents (after dye removal) was significantly lowered compared to the initial dye influents. After the removal of MO and CR, the average root length of bean sprouts was increased from 3.30 cm to 5.18 cm and from 3.01 cm to 7.00 cm, respectively. These findings highlighted the efficient removal of dyes by PRM from aqueous solution, demonstrating the possible application of PRM for the removal of dye from dye-contaminated wastewaters.


2013 ◽  
Vol 16 (1) ◽  
pp. 146-159 ◽  

<div> <p>The purpose of the present work is to test the possibility of using the spent tea dust and raw coir pith for the removal of methylene blue (MB) from aqueous solution. The effects of the contact time, adsorbent dosage and solution pH were studied in batch experiments at 27 &deg;C. Results showed that a pH of 7 is favourable for the adsorption of dye. The isothermal data could be well described by the Langmuir equations. Kinetic parameters of adsorption such as the Langergen pseudo-first-order, pseudo-second-order rate constant and the intraparticle diffusion rate constant were determined. The adsorption capacities of Spent Tea Dust (STD) and Raw Coir Pith (RCP) were found to be 86.21 mg and 142.86 mg g<sup>-1</sup> of the adsorbent respectively. The results indicate that STD and RCP could be employed as low-cost alternatives to commercial activated carbon for the removal of dyes from aqueous solution.</p> </div> <p>&nbsp;</p>


Molekul ◽  
2018 ◽  
Vol 13 (1) ◽  
pp. 63
Author(s):  
I Made Sadiana ◽  
Karelius Karelius ◽  
Retno Agnestisia ◽  
Abdul Hadjranul Fatah

Clay is a natural material from crystalline silicate with layered structures, has high cation exchange capacity, and large surface area. These advantages can be used as an adsorbent for the removal of contaminants in aqueous solutions, such as heavy metals and dyes. In Indonesia, clays from Java, Sulawesi, and Sumatra islands have been used as adsorbent, furniture, and construction materials. Due to limited information about basic characteristics of clay from Kalimantan, this clay has not been utilized well. Therefore, natural clay from Kalimantan, especially in Central Kalimantan, was used as adsorbent of cationic dyes in this present study. However, the clay has difficulty for separating the solid phase from aqueous solution after adsorption process. To solve this problem, combining clay with magnetic material was opted. The objectives of this study are to synthesize the magnetic composite material from natural clay by coprecipitation method and to characterize the synthesized magnetic composite material using an x-ray diffraction method, transmission electron microscopy, and vibrating sample magnetometer. The adsorption properties of the synthesized magnetic composite material were evaluated using rhodamine B and methylene blue dyes in aqueous solution. Before magnetic composite material was synthesized, the clay was previously being activated for removing impurities. The magnetic material formed in the structure of clay had magnetite with particle size of 2.75 nm and the magnetization value of 24.91emu/g. The adsorption capacities of natural clay, activated clay, and magnetic composite of clay in rhodamine B were 34.29, 76.27, and 81.46 mg/g, respectively, while in methylene blue were 30.25, 83.92, and 133.90 mg/g, respectively. These results suggested that magnetic composite of clay can increase the adsorption capacities against dyes and accelerate the separation of the adsorbent solid phase from aqueous solution with largest adsorption capacity on methylene blue dye.


2019 ◽  
Vol 7 (2) ◽  
pp. 240-246
Author(s):  
Kaur Harpreet ◽  
Kaur Harpreet ◽  
Vandana Kamboj ◽  
Vandana Kamboj

Water is the most crucial thing to mankind and so its contamination by various agencies is posing a threat to the natural balance. So, in the present work, the efficiency of various adsorbents derived from plant waste, to remove different dyes from aqueous solution was evaluated. Parameters for study were contact time, concentration and pH. Various combinations of plant ashes were used for the study. It was found that adsorbent prepared from the combination of orange peels, pomegranate and banana peels ashes, exhibited good adsorption capacity for methylene blue, congo red and crystal violet. All these dyes were completely removed from the aqueous solution while methyl orange was not removed. Congo red was removed completely within 40 min of contact with the adsorbent while methyl orange took 3 hrs to be removed to the extent of 48% only. The adsorption coefficient of congo red was found to be 2.33 while value for methylene blue and crystal violet was 1 and 1.66 respectively. The characterization of adsorbent was done by Scanning Electron Microscopy and IR spectroscopy. SEM image revealed the surface of adsorbent to be made of differential pores. From the results it became evident that the low-cost adsorbent could be used as a replacement for costly traditional methods of removing colorants from water.


2018 ◽  
Vol 136 ◽  
pp. 744-752 ◽  
Author(s):  
Abdul Sameeu Ibupoto ◽  
Umair Ahmed Qureshi ◽  
Farooq Ahmed ◽  
Zeeshan Khatri ◽  
Muzamil Khatri ◽  
...  

2019 ◽  
pp. 1-10 ◽  
Author(s):  
Ajayi O. Adesina ◽  
Okoronkwo A. Elvis ◽  
Nelcy D.S. Mohallem ◽  
Sunday J. Olusegun

RSC Advances ◽  
2016 ◽  
Vol 6 (102) ◽  
pp. 100636-100642 ◽  
Author(s):  
Wenzhu Yin ◽  
Huaqiang Cao

In this work, SnO2 functionalized graphene oxide was shown to possess high adsorption capacities and fast adsorption rates for organic dyes over wide pH ranges. Additionally, the adsorbent could be easily regenerated by washing with ethanol.


Sign in / Sign up

Export Citation Format

Share Document