| Natural zeolite is a minieral of hydrated aluminium silicate,consisting of [(Si,Al)04] tetrahedroid. The crystral structures of zeolite are special because they have many equal -sized ducts and holes which are occupied by water moleculars and positive ions . The water moleculars can adsorp and deadsorp reversibly without destroying the crystral structures,After dehydration the holes will be able to hold more moleculars ,In result zeolite possess adsorption property. On the other hand,the positive ions in ducts and holes are weak in combining with negative ions of aluminium silicate,so they can be replaced by other cation ions reversibly ,still keeping the crystral structure. Because of the above properties of adsorption and ions' exchange,natural zeolites can be widely used in various fields such as agriculture petrochemical indusdtry architecture livestock husbandry. enviormental protection and energy application . Compared with synthetical zeolite ,natural zeolite is not only rich in deposit but also low in price. Therefore,its exploitation and utilization are calling great attention from the people.The deposite of stilbites in Guangxi is the only one which possesses industrial importance both at home and abroad at present time. They have high purity and are low in iron element. Their whiteness is up to nearly 90 percents. It is estimated that the stilbite in Guangxi have a great potentiality for exploration because of their excellent properties in adsorption and exchange of ions. Though discovered in 1989,the stilbites haven't received an overall and systematically study on their physical and chemical properties,even though it is necessary for the exploitation and utilization.To meet this end,this thesis deals mainly with the study made under the present experiment condition to properties of adsorption and ions exchange of the stilbites in Guangxi.In order to strenghen the adsorption capacity,two ways for activation are used in my study:roasting and inorganic acid dipping treatment. Between them the former one is better. The best condition for activation and regeneration is roasting at temperature of 200C for one hour. The adsorption capacity of activatied stilbites is 12.4%,and is affected little by the size and relative humidity of enviorment. By regeneration the stilbites can be used repeatly. They can also replace silica gel and activated charcoal as adsorbents.By soaking the stilbites into acid or base solution of various densities at room temperture,We can measure their adsorption capacity,And then the changes of adsorption capacity reflects the acid fastness and alkali fastness of stilbites. The results show that at room temperature the steady state of stilbite require an acid density of 0.1-0.5MHC1 or alkali density of 0.1-0.3MNaOH or strong ammoniao On the other hand ,the complete damage to their structures requires the acid density of 4MHC1 or alkali density of IMNaOH. By testing the influence from the competitive positive ions on the exchange amounts of NH4" in stilbite. it can be seen that the order for one valence or two valences of ions'exchange is K+ > Ag+> Na+>Li+,Ba2"1" >Cu2>Sr2+ >Ca2+>Zn2+> Mg2+ which shows K+ and Ag+ have the priority in the exchange with stilbite.The stilbites in Guangxi are rich in calcium ,the content of calcium oxide is 8.8%.Changing the raw stilbite into Na - exchanged zeolite will contrbute to the ions'exchange. The raise of ion exchange capacity depends on the degree of retrofitting,and which can be jundged by the end of calciun's dissolving ?This thesis discusses the retrofitting solution ways and influences by the factors such as tirn ratio of mass and volume exchanging times and the size. To thin the raw stilbite and then exchange with 20% of sodium chloride solution at the boiling point for 1-2 hours can obtain better effect. After remaking,the property of adsorption and ions exchanging capacity will increase greatly. Then the water -contained rate of 1000 mesh zeolite powder rises from 9.88% to 16.0%,and the C.E.C(cation exchange capacity) fr...
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