Preparation Of Petroleum Coke Derived Activated Carbon And Its Application In Tetracycline Adsorption From Water

Activatied carbon(AC) has been widely used in the field of environmental protection, energy storage, medicine and health, industrial and agricultural production, et al. Especially in recent years, as water pollution becomes more and more serious, activated carbon, as an excellent absorbent, has attracted great attention to the water pollution treatment.In this paper, activated carbon with high specific surface area was prepared by using petroleum coke produced from Xinjiang Karamay, under the protection of nitrogen. The effects of the activation agent, ratio of agent to coke, activation temperature, activation time and flow rate of N2 on the iodine number and yield of AC were investigated. The results showed that under the optimal technical conditions, which are using KOH as agent, KOH to coke 4:1, activation temperature 800 ℃, activation time 0.5 h and flow rate of N2 of 50 m L/min, the obtained AC has an iodine number of 2941 mg/g, the activation yield reached 62.1 %. The as-prepared samples were characterized by the methods of nitrogen adsorption-desorption, SEM, TEM, FT-IR, XPS, Boehm’s titration, elemental analysis and XRD. The results showed that the obtained ACs exhibited a large surface area of 2800-2900 m2g-1 and total pore volumeof 1.4-2.1 cm3g-1. In addition, the oxygen-correlated functional groups endow the obtained ACs with an acid surface.Combining the structural characters with the surface properties, these ACs were successfully applied for the effectively removal of tetracycline(TC), a commonly-used antibiotics, from drinking water. The adsorption parameters, including the contact time, initial concentration, temperature, pH of solution and ionic strength, were investigated. Furthermore, the adsorption isotherms, kinetics and thermodynamics were also discussed in detail. It was observed that the adsorption isotherms were well fitted as a Freundlich model, the kinetics studies implied a pseudo-second-order model. As a typical example, the maximum adsorption capacities of 897.6、961.5 and 1121.5 mg/g were obtained at the temperature of 303, 313 and 323 K according to Langmuir model, respectively, for TC removal, which was higher than that of other reports.