It Is Research For Wei He Sediment Test, It Focus On Its Adsorption Of Nitrobenzene, Desorption Characteristics, Retardation Factor Of The Study

Nitrobenzene is a kind of important organic intermediates in industry, it belongs to the first controlled organic pollutants, it has great harm to human body and environment.In this paper, putting three kinds of sample as the research object in the Wei He river sediments, researching desorption and adsorption’s characteristics of different sample to nitrobenzene and find out the static block factor and dynamic block factor.1. Study on characteristics of Wei He river sediment adsorption:Three kinds of sample in the Wei He river sediment: silt and fine sand, medium sand adsorption dynamics of nitrobenzene in 12 h,12h,8h have reached equilibrium. Adsorption is 8.1 mg/kg, 7.6 mg/kg, 5.8 mg/kg. To Wei He river sediment dynamics curve fitting of the three sample shows Elovich equation after fitting effect is ideal, silt fitting R2 = 0. 959, fine sand fitting R2 = 0. 968, medium sand fitting R2 = 0. 955.For three kinds of Wei He sample after fitting of thermodynamics states that: useing double model can well describe thermodynamic process of sample. silt the fitting degree of silt R2 = 0.993, fine the fitting degree of R2 = 0.994, medium sand the fitting degree of R2 = 0.991. By retardation factor formula is obtained: Silt static block factor Rd=24.28, fine static block factor Rd = 15.78, medium sand static block factor Rd =8.63.This article examines the different factors: Humic acid, salinity, pH, temperature and initial concentration the adsorption’simpact of sediment sample. Humic acid can increase the adsorption of sediment, Salinity can also increase the adsorption of sediment, The increase of temperature will decrease the adsorption quantity of sediment, The sediment adsorption quantity will increase with the increase of initial concentration, The addition of pH will decrease the adsorption quantity of sediment.2. The desorption characteristics of Wei He river sediment research shows that:Three kinds of sample on the dynamics of nitrobenzene desorption equilibrium in 12 hours. Three sample of Wei He river sediment dynamics curve fitting after showing Elovich equation fitting effect is ideal, Silt fitting R2= 0.954, fine fitting R2 = 0.963, medium sand fitting R2 = 0.952.Bring the lag coefficient to thermal desorption of nitrobenzene: getting the data: the lag coefficient of silt HI lag coefficient is greater than the fine sand, Lag coefficient is less than the fine sand medium sand.So the powder sand overall lag phenomenon is most obvious in the desorption process. Retardation factor to describe the adsorption retardation, lag coefficient describes the hysteresis phenomenon in the process of desorption. Retardation factor in the process of adsorption and desorption process of lag coefficient was positively related to relationship.Factors affecting to desorption of nitrobenzene is as same as adsorption. Experiments showed that humic acid and salt(NaCl) join will make nitrobenzene desorption rate decline, The rise of temperature and initial concentration will raise the desorption rate of nitrobenzene.3. Nitrobenzene dynamic experimental study show that:Through the dynamic of nitrobenzene experiment is obtained dynamic block factor Rd = 71.12, Is far greater than the static block factors and Dual mode retardation factor. This shows that the static experiment has its limitations. The reason is the organic pollutant migration mechanism in the process of dynamic experiment more complex but more close to the natural conditions of organic pollutants migration process and Static test is obtained under ideal conditions.