| In recent years,with the rapid development of industrialization,environmental pollution problems getting more serious,wherein,heavy metal ions and dye water pollution is particularly prominent.Water is closely related to life.However,high concentrations of heavy metal ions and dyes in the water will seriously affect the human and nature of all the vitality of animals and plants.Therefore,,the treatment of heavy metal ions and dye pollution in wastewater is of great signifieance.The main chemical methods in wastewater treatment at home and abroad are chemical precipitation method and electrolysis method currently.However,there are some limitations in these methods,such as harsh operating conditions,large dosage and low concentration of wastewater treatment.Therefore,in order to improve the adsorption efficiency of wastewater treatment,and simplify the operation method,the hyperbranched polyamide/mesoporous molecixlar sieve composites were synthesized by hyperbranched polyamide as template,and applied to wastewater study on adsorption of heavy metal ions and dyes as an adsorbent.The main contents are as follows:The hyperbranched polyamide/mesoporous molecular sieve composites HPAMn were prepared by one step of hydrothennal synthesis,and structure was characterized.The adsorption behavior of hyperbranched polyamide/mesoporous molecular sieve composites HPAMn was studied by using heavy metal ions copper,lead,cadmium,mercury,silver and dye metiiyl orange as the research object,1.Different mass ratio of hyperbranched polyamide(HPAMAM-NH2)and cetyltrimethylarnmonium bromide(CTAB)were used as templates.The microporous/mesoporous molecular sieve composites were synthesis by hydrothermal method.The morphology,composition and structure of the hyperbranched polyamide/mesoporous molecular sieve composites was characterized by transmission electron microscopy(TEM),Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TG),Zeta potential and nitrogen adsorption desor:ption(BET).The results show that the morphology of hyperbranched polyamide/mesoporous molecular sieve composites based on different content of hyperbranched polyamide as a template is spherical,and the particle size is about 100-130 nm,have a large specific surface area and specific pore volume,the amount of positively charged on its surface increases with the increase of hyperbranched polyamide content.2.The hyperbranched polyamide/mesoporous molecular sieve composites synthesized with different mass ratios hyperbranched polyamides were applied to the adsorption of heavy metal ions copper,lead,cadmium and mercury in wastewater.And the effects of adsorption time,initiai concentration of heavy metal ion solution,solid-liquid ratio of sample adsorption,initial PH of heavy metal ion solution on the adsorption effect were investigated.The results show that the adsorption capacity of heavy metal ions copper,lead,cadmium and mercury was the highest in the hyperbranched polyamide/mesoporous molecular sieve composites with 45%hyperbranched polyamide as template,and the maximum adsorption capacity of heavy metal ions lead.The initial concentration of heavy metal ions solution has obvious effect on the adsorption efficiency.When the initial concentration of heavy metal ions is 500 ppm,the adsorption capacity can reach the maximun.The adsorption time of heavy metal ions also had a significant effect on the adsorption efficiency.When the adsorption time is 12 h,the adsorption equilibrium is achieved.The adsorption of heavy metal ions lead by hyperbranched polyamide/mesoporous molecular sieve composites conforms to the adsorption kinetics first-order equation.3.The adsorption of dye methyl orange by HPAM45 showed that the adsorption capacity of HPAM45 was the highest when the pH of the solution was 7,the initial concentration was 600 ppm and the adsorption time was 12 h.The adsorption process was in accordance with the Freundlich isotherm model and the adsoxption kinetics satisfy the second-order kinetics equation. |
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