Study on the Adsorption Performance and Adsorption Mechanism of Graphene Oxide by Red Sandstone in Aqueous Solution

Abstract

In order to deal with the increasingly serious pollution of graphene oxide (GO) to the environment. In this paper, the use of red sandstone to treat GO-contaminated aqueous solution is proposed for the first time, and the adsorption capacity and adsorption mechanism of red sandstone to GO are discussed. The controlled variable method was used to explore the optimal pH, concentration, and quality of red sandstone for GO aqueous solution. The adsorption isotherm, thermodynamics, and adsorption kinetics were fitted. Adsorption characterization tests were performed using XRD, AFM, XPS, FT-IR, SAP, TEM, SAP, laser particle size analyzer, and SEM. The results show that when T = 303 K , the optimum adsorption condition of red sandstone for GO is pH = 4 , the mass of the adsorbent is 40 mg, and when the concentration of GO is 80 mg/L, the adsorption capacity is 90 mg/g. The adsorption isotherm model fits the Langmuir model. The adsorption thermodynamic experiments and fitting results show that the reaction is endothermic. XRD and FT-IR tests showed that CaCO3 in red sandstone was involved in the adsorption of GO. SEM, TEM, and AFM microscopic results showed that GO was adsorbed on the surface of red sandstone particles. The XPS test showed that Ca2+ in red sandstone and C=O bond in GO undergo ionic or coordination reaction. The adsorption kinetics fit a pseudo-second-order kinetic model. This study will provide some references for the removal of GO in the environment and the interaction mechanism with natural minerals.

Exploring the Influence of Chemical Conditions on Nanoparticle Graphene Oxide Adsorption onto Clay Minerals

“…[ 79 ] found that GO adsorption on red sandstone increased with increasing temperature under the same GO concentration. This was mainly due to the enhancement of the activity of GO molecules in the aqueous solution, increasing the possibility of GO particles contacting the adsorption active sites [ 79 ]. Ref.…”

Exothermic Reaction in the Cleaning of Wastewater by a Fe2O3/Coconut Shell Activated Carbon/H2O2 Heterogeneous Fenton-like System

“…The modified CSAC particles contained a large number of functional groups that are easily adsorbed and are good carrier materials for Fenton catalysts. The peaks near 3436.528 cm −1 were mainly due to the stretching vibration of O-H bonds in hydroxyl and carboxyl groups [24,25]. The absorption peaks at 1734.656 cm −1 and 1560.612 cm −1 were generated by the stretching vibration of C=O and aryl ring skeleton [24,26].…”

“…The peaks near 3436.528 cm −1 were mainly due to the stretching vibration of O-H bonds in hydroxyl and carboxyl groups [24,25]. The absorption peaks at 1734.656 cm −1 and 1560.612 cm −1 were generated by the stretching vibration of C=O and aryl ring skeleton [24,26]. The peaks at 1091.030 cm −1 corresponded to C-O telescopic vibration peaks [24].…”

“…The absorption peaks at 1734.656 cm −1 and 1560.612 cm −1 were generated by the stretching vibration of C=O and aryl ring skeleton [24,26]. The peaks at 1091.030 cm −1 corresponded to C-O telescopic vibration peaks [24]. The 792.118 cm −1 absorption band indicates the presence of aromatic C-H bonds in CSAS [21,26].…”