Evaluation of micro- and nano-carbon-based adsorbents for the removal of phenol from aqueous solutions
Toxicological and Environmental Chemistry
KACST – Technology Innovation Centre on Carbon Capture and Sequestration (KACST-TIC on CCS), King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia; Department of Chemical Engineering, King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia; Chemistry Department, King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia; Center for Environment &Water, Research Institute, King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia; Department of Mechanical Engineering, King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia; Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, India; Department of Applied Chemistry, University of Johannesburg, Johannesburg, South Africa; Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
This work reports on the adsorption efficiency of two classes of adsorbents: nano-adsorbents including carbon nanotubes (CNTs) and carbon nanofibers (CNFs); and micro-adsorbents including activated carbon (AC) and fly ash (FA). The materials were characterized by thermogravimetric analysis, transmission electron microscopy, Brunauer–Emmett–Teller (BET) specific surface area, zeta potential, field emission scanning electron microscopy, and UV spectroscopy. The adsorption experimental conditions such as pH of the solution, agitation speed, contact time, initial concentration of phenol, and adsorbent dosage were optimized for their influence on the phenol. The removal efficiency of the studied adsorbents has the following order: AC > CNTs > FA > CNFs. The capacity obtained from Langmuir isotherm was found to be 1.348, 1.098, 1.007, and 0.842 mg/g of AC, CNTs, FA, and CNFs, respectively, at 2 hours of contact time, pH 7, an adsorbent dosage of 50 mg, and a speed of 150 rpm. The higher adsorption of phenol on AC can be attributed to its high surface area and its dispersion in water. The optimum values of these variables for maximum removal of phenol were also determined. The experimental data were fitted well to Langmuir than Freundlich isotherm models. © 2015 Taylor & Francis.
Activated carbon; Adsorbents; Carbon nanofibers; Carbon nanotubes; Chemicals removal (water treatment); Efficiency; Electron microscopy; Field emission microscopes; Fly ash; High resolution transmission electron microscopy; Isotherms; Nanofibers; Nanotubes; Phenols; Scanning electron microscopy; Solutions; Thermogravimetric analysis; Transmission electron microscopy; Ultraviolet spectroscopy; Yarn; Adsorption efficiency; Adsorption of phenol; Dispersion in water; Experimental conditions; Field emission scanning electron microscopy; Freundlich isotherm model; Initial concentration; Removal efficiencies; Adsorption; activated carbon; adsorption; aqueous solution; concentration (composition); efficiency measurement; fly ash; fullerene; pH; phenol; pollutant removal; scanning electron microscopy; thermogravimetry; transmission electron microscopy; ultraviolet radiation
KACST, King Abdulaziz City for Science and Technology; AR-30-92, KFUPM, King Abdulaziz City for Science and Technology