| With the rapid development of China's coal chemical industry,while promoting the modernization process,has also brought a large amount of industrial solid waste discharge,which seriously affects the environment and enterprise benefits,in order to realize the utilization of coal gasification solid(CGFS)waste resources to solve its harm has important practical significance.In this paper,CGFS was used as the research object,and 13X zeolite was prepared by hydrothermal synthesis method using CGFS after pretreatment,and its adsorption performance for Cu2+/Cr6+was discussed.The main research is as follows:The influence of pretreatment process on physicochemical properties of CGFS was analyzed.The results show that:the optimal conditions of acid leaching are water bath temperature of 80?,water bath time of 3 h,hydrochloric acid concentration of 2 mol·L-1 and slag acid ratio of 1:25,the content of SiO2 was enriched,the content of Fe2O3 and CaO were reduced,and there is no significant difference between the mineral composition and CGFS,but there were more cracks in the CGFS,the specific surface area increased.The optimal process conditions of alkali melting is m(CGFS-acid leaching:Na2CO3:NaOH)=5:4.5:1.5,CGFS-acid leaching-alkali melts in addition to the chemical composition of the Na2O in certain amplitude is reduced,and the main mineral composition is Na/Si/Al compounds,the particle surface is uneven,due to internal pore structure collapse,specific surface area by drastically reduced.CGFS based 13X zeolite was prepared by hydrothermal synthesis using CGFSacid leaching-alkali fusion as experimental materials.The effects of chemical composition,crystallization temperature and crystallization time on the synthesized product were analyzed.The results show that:n(SiO2/Al2O3)?3.0,n(Na2O/SiO2)=1.9,n(H2O/Na2O)=60,crystallization temperature of 90 0C and crystallization time of 9 h are optimal hydrothermal synthesis conditions.The appearance of optimum CGFS based 13X zeolite is off-white powder,the shape of a positive tetrahedron on the micro.Pyrolysis occurs at 750? in air atmosphere.The surface area was 505 m2·g-1,the total pore volume was 0.334 m3·g-1,and the pore size of particle accumulation was 3.04 nm.The adsorption performance of 13X zeolite for Cu2+/Cr6+ was investigated by batch shock experiment.The results show that the zeolite has a strong adsorption effect on Cu2+,but no adsorption effect on Cr2O72-.The adsorption performance of 13X zeolite-standard sample for Cu2+was compared.The results show that the optimal zeolite dosage is 0.1 g,Cu2+solution concentration is 400 mg·L-1,and solution shock time is 120 min.According to the fitting of adsorption isotherm curve and adsorption kinetics curve,it's found that the adsorption process of 13X zeolite is mainly monolayer chemical adsorption and in the early stage of adsorption is liquid diffusion resistance.It was determined that the adsorption performance of the 13X zeolite was basically the same as that of standard sample.Figure[28]Table[15]Reference[129]... |
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