Preparation Of CaCO <3> And The Adsorption Of Amoxicillin

In recent years, the problem of antibiotic contamination becomes global environment pollution problem, so it is extremely urgent problem to handle different kinds antibiotic in wastewater. CaCO3is friendly material to environment and CaCO3is inorganic material that has varies of morphology and crystalline, which applied to industry widely. In present, Amorphous CaCO3has been applied to handle with the problem of toxic heavy metal Ions pollution, but has not found that CaCO3applied to absorb antibiotic in wastewater. So it is significant for protecting environment to studying preparation of CaCO3with different kinds of microstructure and crystalline. In this paper, different microstructure CaCO3was prepared by different methods and study the property about absorption antibiotic、process of preparation、absorption model、thermodynamic and absorption theory. The whole process include the following five parts:(1)Using CaCL2and (NH4)2CO3as raw materials, CaC03was synthesized by decomposition solvent hot method and studied the performance of Amoxicillin absorption. Preparation conditions was selected by BBD experiment design and is:reaction time is4h, reaction temperature is80℃,n(NH4)2CO3:ncacL2of raw materials mole ratio is1.4:1, rotational speed is60r/min. The influence of reaction time and reaction temperature, raw materials mol ratio, rotational speed and reaction temperature and rotational speed is obvious each other. The CaCO3prepared on the condition of best process were modified by dropping rare earth and the amoxicillin adsorption capacity is248.7μg/g, which increased by24.54%than pure sample.(2)Using CaCl2and Na2CO3as raw material, CaCO3was synthesized by microemulsion method and studied performance of amoxicillin absorption. The optimum process of preparing CaCO3was selected by response surface BBD experiment design. Preparation conditions is:CTAB as reaction model, surfactant concentration is0.15mol/L, reaction temperature is60℃, reaction pH is9. The amoxicillin absorption of CaCO3prepared by the optimum process reached to 333.6μg/g, which increased by67.05%.(3)Using egg shell as raw materials, CaCO3were prepared by carbonization method and used to absorb amoxicillin. The optimum process was studied by orthogonal experimental method. the optimum process is:the mol ratio of raw materials is7.5:1, the reaction temperature is70℃, the CO2flow rate is400L/h, the mix speed is40r/min. amoxicillin adsorption capacity of CaCO3prepared by optimum process reached to325.6ug/g, which increased by63.04than CaCO3prepared by decomposion solvent hot method and reduced preparation cost than CaCO3prepared by microemulsion method.(4). Study absorption model fitting, corresponding thermodynacics and adsorption theory for different morphology of CaCO3prepared by three different methods. The absorption process of different morphology CaCO3conforms to Langmuir model and Freundlich model. Based on the model and the corresponding thermodynamic functions, ΔG0,ΔH0,ΔS0were calculated respectively:-10kJ/mol～0kJ/mol,1.8～22.93J/mol,0.36～77.34J/mol·k. Based on the analysis of absorption model and thermodynamic data, the adsorption process of CaCO3absorb amoxicillin is spontaneous and endothermic. There is physical adsorption of holes accumulation, acting force or chemical adsorption.(5). Morphologies, specific surface area and components of CaCO3were analyzed by SEM, IR, BET, XRD.