Remediation of Toxic Dye Pollutants by Using Graphene‐Based Adsorbents

Abstract

In this article, we report a facile strategy for the synthesis of G@SiO2‐AR by using silica nanoparticles, which are coated with graphene and alkyd resin. During the synthesis of G@SiO2‐AR, the silica particles have been prepared in situ by hydrolysis of tetraethyl ortho silicate (TEOS). The G@SiO2‐AR has been employed to remove the methylene blue (MB) from aqueous solution. G@SiO2‐AR has a strong affinity to adsorb MB as MB is a cationic dye and it is strongly attracted by anions induced by deprotonation of acid functionality on GO. The detailed adsorption characteristics of G@SiO2‐AR, such as adsorption kinetic and adsorption isotherm has been investigated. The efficiency of dye adsorption on a G@SiO2‐AR has been investigated under various parameters such as contact time, temperature, and pH. The adsorption experiment has been carried out by keeping the constant adsorbent dose in 50 mL of 50 ppm dye solution with varying time intervals such as 5, 10, 15, 20 and 25 min at room temperature. We got better results at 20 min and the dye removal efficiency of G@SiO2‐AR and SiO2@AR is 95.08 % and 87.32 % respectively at room temperature. Also, we carried out the same experiment at different temperatures ranging from 298, 308 and 318 K, out of which the highest adsorption efficiency of above‐mentioned adsorbents has been observed at 318 K up to 99.72 % and 93.16 % respectively. Kinetic data has been shown that the adsorption phenomenon follows the pseudo‐second order kinetic model, while adsorption isotherm follows the Langmuir adsorption isotherm.

Application of graphene‐based adsorbents in the treatment of dye‐contaminated wastewater; kinetic and isotherm studies

“…Wang et al [ 31 ] and Xu et al [ 32 ] investigated effective adsorption of MB from aqueous solution to GO‐modified persimmon tannins and triethanolamine‐modified GO. Lokhande et al [ 33 ] synthesized a new adsorbent, the combination of GO, alkyd resin, and silica nanoparticles to suspend the MB from aqueous. Pethsangave et al [ 34 ] presented an easy and productive synthesis of nanocomposite samples of magnetic detachable graphene polyaniline‐ferrite and graphene polypyrrole‐ferrite for photocatalytic use dye degradation of pollutants.…”

Enhanced Decolorization and Treatment of Textile Dye Wastewater Through Adsorption on Acid Modified Corncob Derived Biochar

“…The Langmuir isotherm model provided the best fit with the R 2 value of 0.996 for adsorption of RTDW on MBC and 0.999 for BC at the optimum temperature of 303 K for both the adsorbents as depicted in Figure 6. Thus, it is evident from this that monolayer adsorption of dye molecules has occurred at the homogeneous active sites of both the adsorbents [48] . The value of adsorption intensity i. e. the inverse of heterogeneity factor in Freundlich's isotherm (1/n) below 1 suggests normal adsorption and a value more than 1 reflects the cooperative adsorption [21] .…”

Photocatalytic Degradation of Organic Dyes with Magnetically Separable PANI/Fe3O4 Composite under Both UV and Visible‐light Irradiation

“…[1,2] Remediation of the harmful organic dyes is a vital task for wastewater management due to their complex chemical structure, synthetic origin, carcinogenic, toxicity and explosive to nature. [3] Thus, in search of efficient, non-toxic and green purification technology and advanced materials that could efficiently remove synthetic dyes from wastewater is of great significance for environmental safety. Compared with traditional methods such as adsorption, biodegradation (bacteria), coagulation, the hydrogenation of organic dyes, photocatalytic degradation of dyes exhibits great promise in environmental remediation thanks to the utilization of the solar spectrum (both UV and visible light), low cost and lack of harmful by-products process.…”