Preparation of Phenyl-bonded High Specific Surface Area Activated Carbon and Its Adsorption to Volatile Organic Compounds / 分析化学

ABSTRACT

The activated carbon with high specific surface area was prepared by carbonization with walnut shell as raw material and activation by potassium hydroxide.The surface of activated carbon was then modified by phenyltrimethoxysilane to prepare phenyl-bonded high specific surface area activated carbon adsorption material.The specific surface area and pore size distribution of phenyl-bonded activated carbon were measured by nitrogen adsorption method.The organic functional groups of the phenyl-bonded activated carbon, the chemical environment of the surface elements and the crystal structure were characterized by infrared spectroscopy, X-ray photoelectron spectroscopy and X-ray powder diffraction method.The volatile organic compounds (VOCs) in the air were absorbed by a sampling tube filled with the adsorption material prepared here, then desorbed into carbon disulfide solution and detected by gas chromatography.The saturated adsorption capacities of phenyl bonded activated carbon to 7 kinds of VOCs (ethanol, acetone, hexane, ethyl acetate, tetrahydrofuran, 1,2-dichloroethane, benzene) were in the range of 129-216 mg/g.In the range of 0.05-2.50 mg/mL, there was a good linear relationship between the peak height of the 7 components and the concentration, and the detection limits were in the range of 0.92-3.60 mg/m3.