The adsorption phenomenon occurs at two different phase interfaces. The adsorption process is the diffusion process at the interface, which occurs on the solid surface, which is caused by the residual attraction on the solid surface. Adsorption can be divided into physical adsorption and chemical adsorption; physical adsorption, also known as van der Waals adsorption, is caused by the electrostatic force or van der Waals gravitation between adsorbent and adsorbate molecules. When the molecular gravity between solid and gas is greater than that between gas molecules, even if the gas pressure is lower than the corresponding operating temperature and saturated vapor pressure, the gas molecules will also Physical adsorption is an endothermic process.

化學(xué)吸附亦稱活性吸附，是由于吸附劑表面與吸附質(zhì)分子間的化學(xué)反應(yīng)力導(dǎo)致化學(xué)吸附，它涉及分子中化學(xué)鍵的破壞和重新結(jié)合，因此，化學(xué)吸附過(guò)程的吸附熱較物理吸附過(guò)程大。

Chemical adsorption, also known as active adsorption, is caused by the chemical reaction force between the adsorbent surface and the adsorbate molecules, which involves the destruction and re combination of chemical bonds in molecules. Therefore, the adsorption heat of chemical adsorption process is larger than that of physical adsorption process.

在吸附過(guò)程中，物理吸附和化學(xué)吸附之間沒(méi)有嚴(yán)格的界限，同一物質(zhì)在較低溫度下往往是化學(xué)吸附。活性炭纖維吸附以物理吸附為主，但由于表面活性劑的存在，也有一定的化學(xué)吸附作用。

In the process of adsorption, there is no strict boundary between physical adsorption and chemical adsorption, and the same substance is often chemisorption at lower temperature. The adsorption of activated carbon fiber is mainly physical adsorption, but due to the existence of surfactant, it also has certain chemical adsorption.

3.1活性炭對(duì)VOCs廢氣處理的特點(diǎn)

3.1 characteristics of VOCs waste gas treatment by activated carbon

（1）對(duì)于芳香族化合物的吸附優(yōu)于對(duì)非芳香族化合物的吸附。

(1) The adsorption of aromatic compounds is better than that of non aromatic compounds.

（2）對(duì)帶有支鍵的烴類物理優(yōu)于對(duì)直鏈烴類物質(zhì)的吸附。

(2) The physical adsorption of branched hydrocarbons is better than that of straight chain hydrocarbons.

（3）對(duì)有機(jī)物中含有無(wú)機(jī)基團(tuán)物質(zhì)的吸附總是低于不含無(wú)機(jī)基團(tuán)物質(zhì)的吸附。

(3) The adsorption of inorganic group in organic matter is always lower than that of non inorganic group.

（4）對(duì)分子量大和沸點(diǎn)高的化合物的吸附總是高于分子量小和沸點(diǎn)低的化合物的吸附。

(4) The adsorption of compounds with high molecular weight and high boiling point is always higher than that of compounds with small molecular weight and low boiling point.

（5）吸附質(zhì)濃度越高，吸附量也越高。

(5) The higher the concentration, the higher the adsorption amount.

（6）吸附劑內(nèi)表面積越大，吸附量越高。

(6) The larger the internal surface area of adsorbent, the higher the adsorption capacity.