Effective removal of Cr(vi) using β-cyclodextrin–chitosan modified biochars with adsorption/reduction bifuctional roles

RSC Advances ◽  
2016 ◽  
Vol 6 (1) ◽  
pp. 94-104 ◽  
Author(s):  
Xixian Huang ◽  
Yunguo Liu ◽  
Shaobo Liu ◽  
Xiaofei Tan ◽  
Yang Ding ◽  
...  

In this work, beta-cyclodextrin–chitosan modified walnut shell biochars (β-CCWB) were synthesized as a low-cost adsorbent for the removal of heavy metal Cr(vi) from aqueous solutions.

2012 ◽  
Vol 12 (2/3/4) ◽  
pp. 318 ◽  
Author(s):  
Ali Ahmadpour ◽  
Tahereh Rohani Bastami ◽  
Masumeh Tahmasbi ◽  
Mohammad Zabihi

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Md. Sayedur Rahman ◽  
Kathiresan V. Sathasivam

Biosorption process is a promising technology for the removal of heavy metals from industrial wastes and effluents using low-cost and effective biosorbents. In the present study, adsorption of Pb2+, Cu2+, Fe2+, and Zn2+onto dried biomass of red seaweedKappaphycussp. was investigated as a function of pH, contact time, initial metal ion concentration, and temperature. The experimental data were evaluated by four isotherm models (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich) and four kinetic models (pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models). The adsorption process was feasible, spontaneous, and endothermic in nature. Functional groups in the biomass involved in metal adsorption process were revealed as carboxylic and sulfonic acids and sulfonate by Fourier transform infrared analysis. A total of nine error functions were applied to validate the models. We strongly suggest the analysis of error functions for validating adsorption isotherm and kinetic models using linear methods. The present work shows that the red seaweedKappaphycussp. can be used as a potentially low-cost biosorbent for the removal of heavy metal ions from aqueous solutions. Further study is warranted to evaluate its feasibility for the removal of heavy metals from the real environment.


2017 ◽  
Vol 5 (7) ◽  
pp. 3434-3446 ◽  
Author(s):  
Mingyue Zhang ◽  
Lihua Song ◽  
Haifeng Jiang ◽  
Shu Li ◽  
Yifei Shao ◽  
...  

In order to achieve the reutilization of waste biomass soybean dregs, a low-cost hydrogel, soybean dregs–poly(acrylic acid) (SESD–PAA) was prepared through a one-step reaction.


2018 ◽  
Vol 36 (1) ◽  
pp. 182
Author(s):  
A. Bourliva ◽  
K. Michailidis ◽  
C. Sikalidis ◽  
G. Trontsios

The lead and zinc removal from their aqueous solutions by vermiculite samples from Askos area, Northern Greece, was studied using a batch type method. Askos vermiculite is mainly consisted of mixed-layer phyllosilicates. A standard vermiculite sample from Kent, Connecticut was also used for comparison reasons. The concentration of the solutions used varied between 100 and 2000mg/L The maximum uptake capacity of the Askos vermiculite for lead and zinc was found to reach 95% and 96% from solutions containing 100mg/L, respectively. Much lower uptake capacities: 37% for lead and 76% for zinc were found for the Kent vermiculite. The experimental results showed that the Askos vermiculite exhibited an acceptable high capacity for removing metal ions from aqueous solutions. Thus, this untreated and low-cost mineral can find use in purifying heavy metal wastewaters. The uptake distribution coefficient (Kd) showed that the relative lead and zinc removal is higher for initial concentrations below 1000mg/L Batch adsorption experiments conducted at room temperature (22±1°C) showed that the adsorption patterns followed the Freundlich isotherm model. The heavy metal (Pb2+, Zn2+) removal is a rather complicated phenomenon related both to the aqueous chemistry of the elements and the interaction of their cationic species with the used materials. The removal procedure can be attributed to different processes such as ion exchange, adsorption, and precipitation.


Author(s):  
Tanzeela Kokab ◽  
Hafiza Sumbal Ashraf ◽  
Muhammad Bilal Shakoor ◽  
Asim Jilani ◽  
Sajid Rashid Ahmad ◽  
...  

Heavy metals are the major concern of the modern age. Among the heavy metals, chromium (Cr(VI)) is regarded as a highly toxic heavy metal released largely from leather tanning operations. To remove such high concentrations of Cr(VI), an advanced method is required urgently. Thus, biosorption using biochar, which is an organic material produced from various sources such as walnut shell, can be applied successfully for Cr(VI) abatement. The major objectives of this experiment were the remediation of the Cr(VI) heavy metal using walnut shell biochar and checking of the effect of pH, biochar dosage, Cr level, and shaking time. Remediation of Cr(VI) using walnut shell biochar was proved to be effective and removed the maximum concentration of Cr(VI) up to 93% at pH 5.5, 2 h agitation time, and the biochar amount of 1.1 g L−1 from an aqueous solution. Equilibrium modeling demonstrated that the chemisorption process was involved in adsorption of Cr(VI). The surface of the biochar was porous and provided numerous sites for Cr(VI) attachment, which was also confirmed by the presence of Cr(VI) onto the biochar after adsorption. Hence, the use of walnut shell biochar was highly effective as a sorbent, which could conveniently be applied to small-scale as well as large-scale levels.


RSC Advances ◽  
2016 ◽  
Vol 6 (95) ◽  
pp. 92648-92654 ◽  
Author(s):  
C. Yao ◽  
F. Wang ◽  
Z. Cai ◽  
X. Wang

Nanoscale sorption is a promising strategy for catalyst and purification system design.


2020 ◽  
Vol 381 ◽  
pp. 120980 ◽  
Author(s):  
Doina Humelnicu ◽  
Maria Marinela Lazar ◽  
Maria Ignat ◽  
Ionel Adrian Dinu ◽  
Ecaterina Stela Dragan ◽  
...  

2003 ◽  
Vol 102 (2-3) ◽  
pp. 291-302 ◽  
Author(s):  
Yuen-Hua Wang ◽  
Su-Hsia Lin ◽  
Ruey-Shin Juang

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