Hydrothermal Synthesis of Ultra-Light Coal-Based Graphene Oxide Aerogel for Efficient Removal of Dyes from Aqueous Solutions

Abstract

A novel carboxymethyl cellulose (CMC)-supported graphene oxide aerogel (CGOA) was fabricated from a cost-effective and abundant bituminous coal by a mild hydrothermal process and freeze-drying treatment. Such an aerogel has cross-linked graphene oxide layers supported by CMC, and therefore, displays high mechanical strength while having ultra-low density (8.257 mg·cm−3). The CGOA has a 3D interconnected porous structure, beneficial graphene framework defects and abundant oxygen-containing functional groups, which offer favorable diffusion channels and effective adsorption sites for the transport and adsorption of dye molecules. The adsorption performance of rhodamine B by an optimized CGOA shows a maximum monolayer adsorption capacity of 312.50 mg·g−1, as determined by Langmuir isotherm parameters. This CGOA exhibited a better adsorption efficiency (99.99%) in alkaline solution, and satisfactory stability (90.60%) after three cycles. In addition, adsorption experiments on various dyes have revealed that CGOA have better adsorption capacities for cationic dyes than anionic dyes.

A facile method for coal to graphene oxide and its application to a biosensor

“…Zhou et al [15] used a multi-step process, which involved catalytic graphitization at 2400 C, chemical oxidation, and dielectric barrier discharge plasmaassisted deoxygenation, to convert anthracite to a precursor for graphene. Lv et al [16] converted bituminous coal to graphitic carbon via graphitization treatment at 2800 C, which was then converted to GO via Hummer's method. Fern andez-García et al [17] used impregnation-grade tar and anthracite oil as graphene precursors to produce graphitic carbon via a two-step strategy: carbonization at 650e1000 C followed by graphitization at 2800 C. In another approach, Vijapur et al synthesized large area and transparent graphene film on the Cu foil using anthracite [18] and bituminous coal [19] by CVD around 1000 C. Wu et al [20] fabricated graphene film by spin-coating of coal-derived GO solution via multi-chemical reactions with NaNO 3 , H 2 SO 4 , and HNO 3 , in order.…”

Microcrystalline cellulose/graphene oxide aerogel for adsorption of cationic dye from aqueous solution

“…The capacity adsorption of MB dye adsorbed at time t, q t (mg g −1 ) and at equilibrium time, q e (mg g −1 ) were calculated by the following equations [1,6]:…”

“…Therefore, industrial wastewater treatment before entering the environment is necessary to protect the environment and maintain hygiene, and several methods such as physical, biological and chemical methods have been used to remove dye contaminants [2]. Among these different methods, an adsorption technique owing to the appropriate process, no secondary contamination, low-cost and recyclability, ease and abundance of various adsorbents, especially adsorbents based on nano-particle, graphene oxide (GO), cellulose, etc., has received many attention [1,5,6].…”

Novel recyclable BiOBr/Fe3O4/RGO composites with remarkable visible-light photocatalytic activity

“…Graphene oxide was prepared by a modied Hummers' method, and the detailed synthesis route was reported in our previous work. 33 continuously stirred to form a homogeneous mixture. This homogeneous mixed solution was transferred into a 50 mL Teon stainless steel reactor, and hydrothermal heated at 160 C for 12 h to obtain BiOBr.…”