NiMgAl-LDHs的制备及其对甲基橙的吸附性能研究OA

NiMgAl layered double hydroxide(NiMgAl-LDHs)with satisfactory absorption has been synthesized by hydrothermal method,using nitrates of nickel,magnesium and aluminum and urea as raw materials,whose adsorption properties for methyl orange are studied.The structure of NiMgAl-LDHs is characterized by X-ray diffraction(XRD),scanning electron microscope(SEM),transmission electron microscope(TEM)and Fourier transform infrared spectroscopy(FT-IR).The effects of time,temperature,dosage,solution concentration and pH on the adsorption properties of NiMgAl-LDHs are investigated.Moreover,the kinetics and thermodynamics of NiMgAl-LDHs adsorption for methyl orange are studied.The results show that:NiMgAl-LDHs display uniform size with high degree of crystallinity with a specific surface area of 84.983 m2/g.And the NiMgAl-LDHs shows a higher adsorption performance for methyl orange under acidic condition.When the pH value is 3.0,the adsorbent dosage is 10 mg,the adsorption time is 45 min,the volume of solution is 50 mL and the initial concentration is 40 mg/L,the removal ratio of methyl orange can reach 99.0%.The adsorption process is better described by second-order kinetic model,and the thermodynamics of NiMgAl-LDHs adsorption is better described by Langmuir mode,whose maximum adsorption capacity of NiMgAl-LDHs is 250 mg/g.Thus,the NiMgAl-LDHs prepared in this paper can efficiently and rapidly remove methyl orange by adsorption,exhibiting potential in the treatment of printing and dyeing wastewater.