Search

The water pollution caused by industrial effluents of pollutant dyes has been harmfully affected to the human health and environment. Therefore, it is important for considerable attention to remove them from industrial wastewater before being discharged to the surface water. The natural polymer-based carbohydrate adsorbent with specific functional groups can be enhanced their potential applications toward the notorious dyes removal from wastewater. In this regard, we selected natural adsorbent of graham flour (GF) as an effective adsorbent to remove cationic crystal violet (CyV) dye by the adsorption method. The morphology and structure of GF was characterized in systematic manner by several instrumentations. The several influencing factors such as solution pH, contact time, dose amount, maximum adsorption capacity, competing metal ions effect and reuses behavior were systematically measured. The effective pH range for CyV adsorption was neutral pH region and the maximum adsorption capacity of the GF adsorbent was as high as 162.33 mg/g. The data also clarified that the polymeric GF adsorbent was selectively removed the CyV dye from synthetic polluted sample even in the presence of high concentration of diverse competing ions. The adsorbed CyV dye was eluted with ethanol and simultaneously regenerated into initial form for the next adsorption operations after rinsing with water. Importantly, the natural GF adsorbent was retaining functionality in spite of many steps during adsorption-elution-regeneration cycles. Therefore, the present study revealed that such a low-cost natural polymeric carbohydrate adsorbent could be used as potential adsorbent for the selective dye molecules from wastewater streams. [Display omitted] • Biodegradable natural carbohydrate polymeric adsorbent was used for toxic dye removal. • The adsorbent was exhibited high adsorption capacity with immense sensitivity. • The adsorbent was able reuses in several cycles with loss in its initial performances. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chitosan-based nanocomposite materials were prepared for toxic dye removal. • The methyl orange (MO) was removed with high efficiency by the nanocomposites. • The maximum adsorption capacity was 172.17 mg/g with the fitting of the Langmuir model. The prevalence of dyes in aquatic environments raises severe concerns on a global scale. Methyl orange (MO) is a typical anionic organic dye, which is widely used in industrial wastewater such as textile and paper making. Then the treatment of water contaminated with dyes is an important aspect. The recent decade has witnessed adsorption technology emerging as an advanced dye wastewater treatment with great potential and a grand blueprint, in which the specific surface area and active sites of the adsorbent are considered to be the two most important characteristics largely impacting the adsorption performance. In this study, chitosan-treated nanocomposite was prepared as an effective adsorbent for the removal of MO from contaminated water. The dye removal parameter was performed according to the solution acidity, reaction time, initial concentration, competing for ion affinity, maximum adsorption capacity, and reuse with potential use. The solution pH played a key role in MO dye removal and a suitable pH of 7.0 was selected according to high adsorption ability. The adsorption results were highly fitted with the Langmuir adsorption isotherm model and the maximum adsorption was 172.17 mg/g. The results revealed that introducing chitosan could improve the adsorption capacity and rate effectively even though sacrificing part of specific surface areas of the cotton, indicating that active sites might play a dominant role during the MO adsorption. In addition, the fabricated nanocomposite adsorbent was recycled rapidly by the eluent and regenerated simultaneously, which exhibited the advantages of easy operation as a potentially cost-effective material. The chitosan-based nanocomposite displayed high reusability based on the elution and simultaneous regeneration ability. Therefore, as a cheap green nanocomposite adsorbent with high adsorption performance for MO, chitosan-based fibrous nanocomposite adsorbent is expected to become one of the best candidate materials for future industrial wastewater treatment. [ABSTRACT FROM AUTHOR]

The chemical ligand-based conjugate adsorbent was prepared for selective and sensitive toxic lead (Pb(II)) ions monitoring and removal from contaminated water to save water quality and human health. Both in the monitoring and removal operations, the solution pH played a vital role by the conjugate adsorbent. The data clarified that pH 3.50 was suitable for simultaneous monitoring and removal of Pb(II) ions. In the monitoring, a significant color was formed upon the addition of Pb(II) ion even in the presence of ultra-trace level. Then the solution pH, reaction time, foreign ion, and initial concentration effect were systematically measured. The conjugate adsorbent exhibited an extremely low detection limit (0.35 µg/L) to comply with the material's applicability in real sample onsite monitoring. In the reaction time effect, color optimization and high removal efficiency was achieved by increasing the reaction time. However, the diverse foreign ions were not adversely affected in the monitoring and removal to clarify the conjugate adsorbent as sensitive and selective towards the Pb(II) ions. The conjugate adsorbent was shown highly ordered structure and was able to open high functionality for Pb(II) ion monitoring and removal. The adsorption data also revealed that the present conjugate adsorbent exhibited adsorption capacity (172.87 mg/g) and was well fitted by the Langmuir adsorption isotherm with monolayer coverage. The adsorbed Pb(II) ion was desorbed using 0.30 M HCl and then simultaneously regenerated into the initial form for several cycles use after rinsing with water. Then it is expected that the optimum protocol effectively captured the Pb(II) in a sustainable and environmentally friendly manner for the production of clean water to safeguard public health and environmental remediation. [Display omitted] • A novel conjugate adsorbent was proposed for Pb(II) ion monitoring and removal. • The conjugate adsorbent exhibited high selectivity and sensitivity to Pb(II) ions. • The adsorbent also exhibited high Pb(II) adsorption capacity and low detection limit. [ABSTRACT FROM AUTHOR]