Preparation Process Of Impregnated Activated Carbon

The core of the preparation of impregnated activated carbon lies in the thorough contact and combination of the activated carbon carrier and the active component solution. The standard impregnation process first requires that the pre-treated activated carbon (with a particle size of 2-3mm and a specific surface area of ≥1000m²/g) be placed in a vacuum drying oven at 110℃ for dehydration for 2 hours, and then transferred to a closed impregnation tank. When preparing the impregnation solution, accurately weigh the soluble salts such as silver nitrate and palladium chloride according to the target metal loading (usually 0.5-5wt%), and mix them with deionized water to form a 0.1-0.5mol/L solution and adjust the pH to 3-5. The solution is slowly injected into the impregnation tank by the equal-volume impregnation method. The liquid level height should fully cover the activated carbon layer and maintain a margin of 2cm. At the same time, the ultrasonic oscillation device (with a frequency of 40kHz) is turned on to assist in permeation for 2 hours. After the impregnation is completed, the solid and liquid are separated by vacuum filtration. The filter cake is placed in a programmed temperature-controlled drying oven and heated step by step: pre-drying at 60℃ for 1 hour → curing at 80℃ for 2 hours → completely removing the crystalline water at 120℃. The final product needs to be heat-treated at 300 ° C for 1 hour under nitrogen protection to complete the fixation of active components. After XRD detection confirms the formation of metal oxide crystal forms, it is a qualified finished product. During the entire process, the solution concentration, impregnation time and drying curve are the three key parameters that affect the uniformity of the load.