Study On Preparation Of Activated Carbon From High Sulfur Petroleum Coke

High sulfur petroleum coke refers to more than 3%sulfur content of petroleum coke,most of it is used as power generation fuel.The high value utilization of high sulfur petroleum coke has become the focus of research.Preparation of activated carbon from high sulfur petroleum coke is one of the application directions of high sulfur petroleum coke.In the process of preparing activated carbon,the sulfur element in the high sulfur petroleum coke will have certain influence on the basic activator when activated.At the same time,the density of petroleum coke makes the effect of activation need to be improved.Activator cost is expensive,washing activated carbon produces a lot of waste acid waste liquid three main problems.In this paper,the high sulfur petroleum coke and iron and iron oxides are used as desulfurization agents for pre-desulfurization,and K₂CO₃ is used as the activator and appropriate treatment methods are selected to increase the activation effect and improve the adsorption performance of the activated carbon prepared.Finally,the activator is recovered by leaching,and the activator is recycled,which will make the activation process more low cost and green.The products were characterized and analyzed by X ray energy spectrum analysis,X ray diffraction,X ray photoelectron spectroscopy,nitrogen adsorption apparatus,scanning electron microscope,iodine value measurement and p H dynamic measurement.The results show that the optimal process conditions are as follows:Fe（0.5-3 mm）as desulfurizer,L-F as the contact mode,reaction temperature is 1000℃,reaction time is 60min,reaction order is 4-step reaction,the desulfurization rate is 40.53%..The optimum process conditions for Fe S recovery are as follows:reaction temperature is 600℃,reaction time is6min;Three methods are used to enhance the activation effect of activated carbon prepared from petroleum coke:（1）In ethanol solution containing 8%water,soaking time of 6h and soaking temperature of 35℃.The activated carbon with maximum specific surface area and iodine adsorption value are 882.3 m²·g^-1 and 1237.0mg·g^-1,respectively.（2）The optimal pretreatment method is ultrasonic impregnation.The specific surface area and iodine adsorption value are 997.4 m²·g^-1 and 1284.6 mg·g^-1,respectively.（3）The specific surface area and iodine adsorption value of activated carbon with iron oxide as catalyst increased,and the average pore size and mesopore volume increased greatly.The optimal conditions for the recovery of activator by leaching are as follows:the ultrasonic temperature is 25℃,the flow rate is 30 m L·min^-1,and the time for the activated carbon to be nearly neutral is 13 min,with the addition of ultrasound,the leaching time can be greatly shortened under room temperature leaching conditions.The reuse experiment of the recovered activator is carried out,and the results showed that the adsorption performances of activated carbons prepared are higher than that of the first time with the increase of reuse times.Meanwhile,the pore structure of the activated carbon is changed,the average pore size is increased,the mesoporous volume is increased,and the micropore volume is decreased slightly.The recovered activator components are studied and it is found that amorphous K₂CO₃ was still the main component in the activator,accompanied by a small amount of sulfate,hydroxide and sulfide.