Nano-Y Zeolite Synthesis And Study Of Flue Gas Mercury Removal For

Nanoscale zeolites have high specific surface area, uniform radial distribution ofskeleton components, high intracrystalline diffusion rate and so on. People always payattention to them. As they are becoming more and more widely applied in theproduction and living, the research of the synthesis of nanoscale zeolites hassignificant meaning to promote the further application. The synthesis of nanoscalezeolites has been the focus in the people’s research work.The nanoscale NaY zeolite was synthesized by hydrothermal synthesis methodwhile the commercial sodium silicate used as raw material. Influence ofpolyoxyethylene sorbitan monolaurate （Tween-20）, acetic acid and the mixture ofpolyoxyethylene sorbitan monolaurate （Tween-20） and acetic acid, n-hexane,cyclohexane, the mixture of n-hexane and cyclohexane and reaction conditions on thesynthesis of NaY zeolite was investigated in detail. The samples were characterizedby XRD, BET, SEM, TEM and NH₃-TPD technique. The result showed that theaddition of Tween-20, acetic acid, the mixture of Tween-20and acetic acid, n-hexane,and cyclohexane could reduce the crystalline size of NaY zeolite. Adding the mixtureof Tween-20and acetic acid was better than that of single added Tween-20or aceticacid. The superfine NaY zeolite could be synthesized when the Tween-20content was0.1%of the A1₂O₃content of synthesis system, and acetic acid content was150%ofthe A1₂O₃content of synthesis system in the mixture. The grain size of product wasabout180nm. Adding the mixture of n-hexane and cyclohexane was worse than thatof single added n-hexane or cyclohexane. Adding n-hexane was better than that ofadded cyclohexane and the mixture of Tween-20and acetic acid. The superfine NaYzeolite could be synthesized when the n-hexane content was100%of the A1₂O₃content of synthesis system. And the grain size of product was about130nm. Thereaction conditions were optimized with the right amount n-hexane added. The resultshowed that the NaY zeolite with fit size distribution and high specific surface areacould be synthesized when the alkalinity was6.0and the alumino silica gel wascrystallized at100℃for4hours. In addition, the grain size of product was about100nm.The adsorption of mercury used maternal and modified NaY zeolite was investigated on the basis of the stable synthesis of100nm NaY zeolite. Influence offactors such as the particle size of NaY zeolite and the gold load on the adsorptionproperty was investigated. The result showed that the maternal HY zeolite through ionexchange had a certain adsorption property to mercury in flue gas. The adsorptionproperty was depending on the grain size of Y zeolite, the initial concentration ofmercury, dosage of zeolite and so on. With the decrease of the grain size of HYzeolite, the adsorption property increased. The adsorption efficiency of Y zeolite wasfit when the initial concentration of mercury was0.00628μg/mL and the dosage ofzeolite was0.6g. The adsorption efficiency of100nm HY zeolite could reach80.8%.Compared with maternal HY zeolite, the adsorption property of HY zeolite wassignificantly improved by loading gold. The adsorption efficiency of Y zeolite was fitwhen the initial concentration of mercury was0.00628μg/mL, the dosage of zeolitewas0.6g and the gold load was0.8%of the quality of Y zeolite. The adsorptionefficiency of Y zeolite could reach96.9%.