CAJ | 학술논문

采用IGA - 100型智能重力分析仪测定在100 ～300℃,0.01 ～ 10 kPa下,5A分子筛对正己烷的吸附速率曲线,分析了不同二次孔分布的成型5A分子筛颗粒5A-1和5A-6对正己烷的吸附扩散性能.结果表明:5A-1与5A-6分子筛具有相近的微孔和中孔孔径分布；5A-6分子筛在孔径0.1～1 μm范围内拥有相对更大的二次孔孔容,而在孔径小于0.01 μm时拥有更丰富的二次孔分布；丰富的二次孔分布使得正己烷在5A-6分子筛上的有效扩散系数De为10-6～10-4cm2/s,是5A-1分子筛的2～5倍；随着吸附温度从100℃增大至300℃,5A-1分子筛上的有效扩散系数从5×10-7～2×10 -6cm2/s增大至2×10 -5cm2/s,而在5A-6分子筛上的有效扩散系数随着吸附温度变化不明显；吸附压力从0.01 kPa升高至10 kPa,引起正己烷分子平均自由程从627.15 ～ 963.28 μm下降至0.63 ～0.96 μm,并与分子筛二次孔孔径相当,引起Knudsen扩散加剧,从而使正己烷在5A分子筛上的有效扩散系数于压力l kPa前后呈现先上升后下降的变化趋势.
채용IGA - 100형지능중력분석의측정재100 ～300℃,0.01 ～ 10 kPa하,5A분자사대정기완적흡부속솔곡선,분석료불동이차공분포적성형5A분자사과립5A-1화5A-6대정기완적흡부확산성능.결과표명:5A-1여5A-6분자사구유상근적미공화중공공경분포；5A-6분자사재공경0.1～1 μm범위내옹유상대경대적이차공공용,이재공경소우0.01 μm시옹유경봉부적이차공분포；봉부적이차공분포사득정기완재5A-6분자사상적유효확산계수De위10-6～10-4cm2/s,시5A-1분자사적2～5배；수착흡부온도종100℃증대지300℃,5A-1분자사상적유효확산계수종5×10-7～2×10 -6cm2/s증대지2×10 -5cm2/s,이재5A-6분자사상적유효확산계수수착흡부온도변화불명현；흡부압력종0.01 kPa승고지10 kPa,인기정기완분자평균자유정종627.15 ～ 963.28 μm하강지0.63 ～0.96 μm,병여분자사이차공공경상당,인기Knudsen확산가극,종이사정기완재5A분자사상적유효확산계수우압력l kPa전후정현선상승후하강적변화추세.
Adsorption rates of n-hexane on the 5A zeolite at 100 to 300 ℃ and 0.01 to 10 kPa are determined by an intelligent gravimetric analyzer (IGA-100),and the adsorption diffusion performance of n-hexane on 5A zeolite pellets with different secondary pore distributions is analyzed.The results indicate that 5A-1 and 5A-6 zeolites have similar micropore and mesopore size distribution,while the 5A-6 zeolite has a larger secondary pore volume when the pore diameter is between 0.1 and i μm and more secondary pores when the pore diameter is less than 0.01 μm.The effective diffusion coefficient of nhexane on the 5A-6 zeolite pellet is 10 -6 to 10 -4 cm2/s,about 2 to 5 times higher than that on the 5A-1 zeolite.The effective diffusion coefficient of n-hexane on the 5A-1 zeolite pellet improves from 5 × 10-7 to 2 × 10-6cm2/s when the temperature increases from 100 to 300 ℃.However,the effective diffusion coefficient of n-hexane on the 5A-6 zeolite remains almost unchanged at different temperatures.The molecular average free path of n-hexane decreases from 627.15-963.28 to 0.63-0.96 μm with the adsorption pressure increasing from 0.01 to 10 kPa.Such a free path is close to the secondary pore diameter,resulting in significant Knudsen diffusion in the secondary pores.Thus,the effective diffusion coefficient of n-hexane on the 5A zeolite pellets increases before 1 kPa and decreases after 1 kPa.