| Pentachlorophenol (PCP) as well as its sodium salt (PCP-Na) is a kind of prior control pollutes in many countries. It had been widely used as herbicide, antiseptic, insect-resist agents. In recent years, PCP has been forbidden to be produced and be used. However, it still remains in the environment and its noxious effect will be long exiting. Because of its universality in environment and its persistent, high toxicity risk to human beings, it is very important to study the adsorption and degradation of PCP in environment.1. The absorption and desorption about static state and dynamic state of sodium pentachlorophenol on the loess of three different depth had been studied in this passage. At the same time, the equations of adsorption thermodynamics and adsorption kinetics had been used to describe its characteristics. The result showed that: Sodium pentachlorophenol on soil of three different depth had some measure of absorption capacity, and in 90 min they all achieved equilibrium in which the saturated extent of adsorption of eluvial horizon was 50μg/g, illuvial horizon was 43.48μg/g, C-horizon was 40μg/g. Freundlich adsorption isotherm can be used to describe the adsorption of sodium pentachlorophenol on loess appropriately. When pH value was less than 5 (the soil reacts acid), the adsorption capacity of sodium pentachlorophenol increased with pH value decreased. Moreover, the adsorption capacity of sodium pentachlorophenol increased with ionic strength increased. In the dynamic adsorption experiment, the soil eluviated by 5μg/mL sodium pentachlorophenol solution, while adsorption time was 400min and effluent liquid volume was 750mL, the adsorption of eluvial horizon achieved balance. While adsorption time was 510min and effluent liquid volume was 850mL, the adsorption of illuvial horizon achieved balance. While adsorption time was 550min and effluent liquid volume was 820mL, the adsorption of C-horizon achieved balance. In the dynamic desorption experiment, we continued to use tap water to eluviate the soil. While desorption time was 820min and effluent liquid volume was 400mL, the desorption of eluvial horizon achieved balance. While desorption time was 1135min and effluent liquid volume was 500mL, the desorption of illuvial horizon achieved balance. While desorption time was 1450min and effluent liquid volume was 550mL, the desorption of C-horizon achieved balance.2. The static and dynamic adsorption of sodium pentachlorophenol on the activated carbon had been studied. The results showed that: The absorption capacity of sodium pentachlorophenol on activated carbon was well. In 90min, the adsorption achieved equilibrium, and equilibrium adsorption capacity was 1.947mg/g. Freundlich adsorption isotherm can be used to describe the adsorption of sodium pentachlorophenol on activated carbon appropriately. Correlation of coefficient was 0.981. The absorption capacity made no difference between pH value from 5 to 11. In the dynamic experiment, 2.5g activated carbon-loaded column eluviated by 40μg/mL sodium pentachlorophenol. While effluent liquid volume is 630 mL, the adsorption of activated carbon achieved saturation point. On different concentrations of pentachlorophenol solution, the higher is the concentration, the higher is the rate of absorption. The slower is the flow velocity, the higher is the rate of absorption. The highest absorption rate could reach 100%.3. The static and dynamic adsorption/desorption of sodium pentachlorophenol on macroporous adsorption resin HDX-8 had been studied. The results showed that: In 70min, the adsorption achieved equilibrium. The static saturated extent of absorption was 7.351mg/g, Freundlich and Langmuir adsorption isotherm can be used to describe the adsorption of sodium pentachlorophenol on HDX-8 appropriately, and the correlation of coefficient was above 0.99. Using 1mol/L NaOH solution as strippant, desorption rate was 77%, and the equilibrium time of desorption was 120min. In the dynamic adsorption experiment, the smaller is the solution and the slower is the flow velocity, the higher is the adsorption rate. The highest absorption rate could reach 99.56%. In the dynamic desorption experiment, using 1mol/L NaOH solution as strippant at a speed of 0.5mL/min, desorption effect was the best, and desorption rate could reach 96% or more.
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