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1 – 2 of 2Ali Hassanzadeh, Ebrahim Ghorbani-Kalhor, Khalil Farhadi and Jafar Abolhasani
This study’s aim is to introduce a high-performance sorbent for the removal of both anionic (Congo red; CR) and cationic (methylene blue; MB) dyes from aqueous solutions.
Abstract
Purpose
This study’s aim is to introduce a high-performance sorbent for the removal of both anionic (Congo red; CR) and cationic (methylene blue; MB) dyes from aqueous solutions.
Design/methodology/approach
Sodium silicate is adopted as a substrate for GO and AgNPs with positive charge are used as modifiers. The synthesized nanocomposite is characterized by FTIR, FESEM, EDS, BET and XRD techniques. Then, some of the most effective parameters on the removal of CR and MB dyes such as solution pH, sorbent dose, adsorption equilibrium time, primary dye concentration and salt effect are optimized using the spectrophotometry technique.
Findings
The authors successfully achieved notable maximum adsorption capacities (Qmax) of CR and MB, which were 41.15 and 37.04 mg g−1, respectively. The required equilibrium times for maximum efficiency of the developed sorbent were 10 and 15 min for CR and MB dyes, respectively. Adsorption equilibrium data present a good correlation with Langmuir isotherm, with a correlation coefficient of R2 = 0.9924 for CR and R2 = 0.9904 for MB, and kinetic studies prove that the dye adsorption process follows pseudo second-order models (CR R2 = 0.9986 and MB R2 = 0.9967).
Practical implications
The results showed that the proposed mechanism for the function of the developed sorbent in dye adsorption was based on physical and multilayer adsorption for both dyes onto the active sites of non-homogeneous sorbent.
Originality/value
The as-prepared nano-adsorbent has a high ability to remove both cationic and anionic dyes; moreover, to the high efficiency of the adsorbent, it has been tried to make its synthesis steps as simple as possible using inexpensive and available materials.
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Eman Salim, Wael S. Mohamed and Rasha Sadek
Paper aims to evaluate the efficiency of traditional chitosan, nano chitosan, and chitosan nanocomposites for consolidating aged papyrus samples. Cellulose-based materials, such…
Abstract
Purpose
Paper aims to evaluate the efficiency of traditional chitosan, nano chitosan, and chitosan nanocomposites for consolidating aged papyrus samples. Cellulose-based materials, such as papyrus sheets and paper, which are the most common types of writing supports for works of art in many museums and archive. They are subjected to different types of deterioration factors that may lead to many conservation problems. Consolidation treatment is one of the most common conservation treatments, which should have perform after much testing to select the appropriate consolidants.
Design/methodology/approach
This research paper aims to evaluate the resistance of traditional chitosan, nanochitosan and chitosan/zinc oxide nanocomposite as an eco-friendly papyrus strengthening. Untreated and treated papyrus was thermally aged and characterized via scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). Antimicrobial activity of the papyrus specimens was also determined against four tested pathogenic bacteria by disc diffusion method: MRSA, Staphylococcus aureus, E. coli and P. aeruginosa.
Findings
The results revealed that chitosan nanocomposite showed a remarkable enhancement of papyrus tensile properties and presence of ZnO prevents the effects of biodeterioration.
Originality/value
Zinc oxide nanoparticles enhance the optical properties and increase the chemical reactions between the consolidating material and the treated papyrus.
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