Adsorption Process Of Endocrine Disruptors Compounds On The Surface Of The Filter

Endocrine disruptors compounds is a kind of exogenous agent that has an interfere effect on the synthesis, secretion, transport, binding, action, or elimination of natural hormones which is related to the maintenance of homeostasis, reproduction, development, and behavior in the human’s and animal’s body. The natural and synthetic EDCs are released into environment(surface water, rainfall, soil, agricultural irrigation, ground water), and they can enter into the drinking water through the water cycle. So many kinds of EDCs are identified in dringking water. The hormones effection in body can be imitated, intensified or disturbed by EDCs, what’s worse, it may laed to the hyperplasia of tissues or organs, even tumour. Therefor, the question of the removal of these compounds through conventional drinking water treatment processes is an emerging concern and is a real issue considering human health.Quartz crystal microbalance is a kind of converter for quality and frequency, witch operate as an mass detector based on the principle that a resonating quartz crystal changes frequency when a material adsorbs on its surface. The minimum detectable mass change is typically about 1ng.The QCM can be used in the changes and mechanisms in a microprocess analysis and detection. QCM can realize the detection of different compounds after the surface of the quartz cystal is typically coated with different surface materials.In this paper, gold sputtered wafers were coated with(3-mercaptoproply) trimethoxysilane(3-MTPS) in silica and zeolite particle aqueous suspensions, enabling to produce a QCM mass adsorption detection sensor. In the QCM system, the silica was obtained according to the Stober. FESEM was used to analysis the surface topography of silica and zeolite,. The SEM image showed the particle diameter of slica was smaller than zeoite, and the silica particles were a kind of microsphere, while the zeolite had an nonuniform surface. The BET-N2 adsorption test results showed that the adsorption efficiency of silica was better than zeolite. Accoding to XRD images, silica was amorphous state, while the zeolite had a better crystal form. The SEM test for the distrntion of the tow adsorbents on the QCM chips showed the gold surfaces homogenously covered with tow-dimensional clusters of silica and zeolite.Bisphenol A(BPA), estrone(E1), 17β-estradiol(E2) and sulfamethoxazole(SMZ) were selected as foue representative EDCs in water environment. The QCM sensor was used to test the adorption of the four EDCs on the surface of silica and zeolite and analysis the adsorption process, mechanism, affecting factors.The main results of this work are drawn:1) In the sdsorption kinetics experiments of the four EDCs on silica and zeolite, it was needed about 10 min to reach equilibrium for the EDCs adsorption on the silica and zeolite. The QCM mass response time of silica on the QCM was faster than that of zeolite for the reson that silica had a larger specific surface area. Psudo-first order kinetics model was reasonable described the four selected EDCs adsorption process. The adsorbing capacity was related to the molecular structure, the electric property and molecular polarity of the EDCs.2) Fteundlich and Langmuir isothermal model were well fitted the adsorption of the four EDCs on silica and zeolite. Freundlich sothermal model was more fit for the EDCs sdorption on silica, while Langmuir isothermal model could reasonable describe EDCs adsorption of zeolite. The results showed the hydrophobicity of the conponds was related to the adsorption capacity.3) The initial concentration of the four EDCs nearly had no effect on the adsorption efficiency. p H didn’t change removal ratio obviously, but the QCM mass response time at p H 5.5 was much faster than that at p H 8.5. p H might change the surface charges of silica and zeolite. Ionic strength also shorten the QCM mass response time, but didn’t apparently affect the removal ratio.