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5A Molecular Sieves

5A Molecular Sieves

中文名：5A分子筛

Chemical Formula: 3/4CaO*1/4Na₂O*Al₂O3*2SiO₂*9/2H₂O

Specification

Packing and Storage

25kg/carton, 150kg/steel drum

On room temperature, relative humidity not more than 90%; not lay bare in the air; keep away from water, acid and soda

Introduction

5A molecular sieve, also called Calcium A molecular sieve, non-toxic, odorless, nonflammable, non-explosive, insoluble in water and organic solvents, but soluble in strong acid and strong base. Its pore diameter is 5×10^-10m, can adsorb any molecules which pore diameter is smaller than 5×10^-10m. In addition to the effect of 3A, 4A molecular sieves, it also can adsorb C3-C4 n-alkanes, ethylene chloride, bromoethane, butanol, etc. 5A molecular sieve can be applied to pressure swing adsorption separation, heterogeneous hydrocarbon separation and coadsorption of water and carbon dioxide. Yuanying 5A molecular sieve has ion exchange capacity and catalytic activity, also has a great affinity to water, under high temperature still has good adsorption ability, it has good catalysis to some organic gas phase reaction.

Molecular sieve also called zeolite, is a crystalline aluminum silicate. Its crystal structure has neat and uniform channel, aperture around a molecular level, molecular sieve only allows smaller diameter than its aperture into it, so it can sieve molecules according to their size in the mixture, so it called molecular sieve. According to molecular sieve aperture size, there are 3A, 4A, 5A, 10X, 13X. 4A molecular sieve is Na-A molecular sieve, aperture 0.4nm; if Na replaced by K, aperture 0.3nm, is 3A molecular sieve; if over 1/3 Na replaced by Ca2+, aperture 0.5nm, is 5A molecular sieve.

Let sodium aluminate, sodium silicate and sodium hydroxide hybrid reaction according to certain molar ratio (normally Al₂O₃:SiO₂:Na₂O:H₂O=1:2:3:185), keeping temperature>40℃, with violent stirring, heating up reaction gel to102℃±2℃, remain this temperature till static crystallization, then filtration washing, adding calcium chloride for ion exchange (exchange 70%), then filtration washing, drying, adding adhesives kneading, molding, finally burning activating get 5A molecular sieve.

Application

1. The depth desiccation and purification of gases and liquids, purification of nitrogen, hydrogen, cleaning hydrogen sintering furnace

2. Through a selective adsorption process, isolated n-alkane frombranched-chain hydrocarbon and cyclic hydrocarbon, currently in industry used for large-scale pressure alkane separation process

3. Desiccation, desulfurization, removal of carbon dioxide for petroleum, petroleum gas and natural gas

4. Nitrogen oxygen separation, nitrogen hydrogen separation, making oxygen, nitrogen and hydrogen

5. Petroleum dewaxing, can be used as a adsorbent in dewaxing technology based on vapour as desorbent.

5A molecular sieve regeneration

1. Moisture removal: According to pressure, temperature and water of regenerate gas. Normally 200～350℃ dry gas under 0.3～0.5kg/cm through molecular sieve bed layer 3-4 hours, exit temperature 110～180℃, then cooling.

2. Removing organic matter: Used vapour instead of organic matter, then repeat step 1.