SU1066940A1 - Cesite production method - Google Patents

Abstract

METHOD OF OBTAINING. CELLE, including the crystallization of alumina silica in the presence of gel - composition

Description

The invention relates to the production of synthetic aluminosilicate sorbents and can be used in the chemical, petrochemical, and petroleum refining industries. A method for producing synthetic crystalline aluminosilicate cesium cesite 11 is known. According to this method, initial aqueous solutions containing silicon aluminum, sodium, and cesium are mixed. The sodium source may be sodium silicate, sodium aluminate and sodium hydroxide, a source of silicon, sodium silicate, colloidal silica sol or silica gel, sodium aluminate, aluminum trihydrate or aluminum alumina sol. Water is added separately or as a component of a certain composition, cesium in the form of hydroxy diadium. All components are mixed at ambient temperature, kept at this temperature for 3-7 days, heated at 50-110 seconds (preferably 6090 ° C, particularly preferably at) The reaction mass is maintained until a crystalline product OT 3 is formed to 60 days (preferably from 7 to 21 days. The pressure used is close to atmospheric, the crystallization time range is 1-42 days, depending on temperature. After the crystalline phase of the zeolite has been formed, the crystals are filtered off from the mother liquor and washed to a pH of 10-12. As a result, a new synthetic narrow porous crystalline aluminosilicate cesium zeolite of the RhO type with a pore size of about 5A is obtained. The finished product has the following molar ratio of oxides: C4.0-0, l) Cs20. (0.6-0.9) xx Al2.0 (5.8-6.3) Si 0 (0-10.0) NgO. The closest to the proposed technical essence and the achieved result is a method of obtaining cesium, crystallizing in the system CsgO-Na gO-A1g0.5-5102-HgO using x-ray amorphous seeds 2, According to the known method of crystallization is subjected to a reaction mass consisting of 2 gels in the volume ratio of the main gel g of the seed gel: 97.5 S2.5% by volume. According to this method, an initial basic hydrogel is prepared as follows. Mix the solutions of sodium silicate, sodium aluminate, aluminum sulfate and cesium hydroxide. The source of sodium and water are alkaline solutions of sodium alnminate and sodium silicate. All components are mixed at ambient temperature, the resulting initial hydrogel has the following molar ratio of oxides: 0.32Cs O 3.5MagO AJ. 2. J lOSiOg X X 19 OH 5.0, An X-ray amorphous seed, which is a hydrogel, is prepared by mixing solutions of sodium aluminate, sodium silicate, sodium hydroxide and cesium hydroxide. The composition of the seed has the following molar ratio of oxides: 0,. 12Ka20 AlgOj-lOSiO x X 240K9 0. Thus, according to the well-known method, cesium hydroxide is part of the basic gel and the priming gel. X-ray amorphous seed in the amount of 2.5 vol% is added to the initial hydrogel and stirred until complete homogenization. The resulting reaction mass is crystallized at a temperature. The duration of crystallization is 6-16 hours. The resulting product is washed from the mother liquor, dried at 120-130 ° C. Get the synthesized product: matrix-cesium -. A new zeolite-zeolite, which is an analogue of a synthetic crystalline aluminosilicate cesium zeolite of the RhO type. The finished product has the following molar ratio of oxides: 0.33Cs20 3, bbKa OlyOj-8, Ob310 ' XX 191,5HjO, The disadvantage of the known method of producing zeolite-cesite is its high cost and significant consumption of expensive cesium hydroxide component using it to prepare both the original hydrogel. The aim of the invention is to increase the absorption capacity and reduce the cost of the process. This goal is achieved by the fact that according to the method of obtaining cesium, including crystallization of aluminum silica in the presence of a gel, the seed composition (0.6-1, O) CsjOx. Ch10-16) Ke.yO MgOg (10-15) (200-300) HO at elevated temperature, washing and drying, crystallization is subjected to silica alumina of the composition (2.8-3.2) Na, (43-10) 310 (160-200) 1120, and gelatrix taken in an amount of 5-15 Alumina silica is obtained by mixing silicon-containing raw material — sodium silicate with aluminum-containing components — sodium aluminate and aluminum sulfate and water. The molar ratio of oxides in the main gel is as follows: (2.8-3.2) Na20. , (8-1 O) SiO.x X (160-200) 1120. At the same time, a priming of sodium-cesium alumina-silica gel is prepared by mixing aqueous solutions of sodium aluminate, sodium hydroxide, cesium hydroxide and sodium silicate. The composition of the gel is as follows: (O, 6-1.0) (10-16) Na20 XX AHgOz (10 -15) si02 (200-320) HgO This composition corresponds to the crystallization region of sodium-cesium zeolite. The gel seed is added to the main gel, mixed and a homogenized reaction mass is obtained, which is crystallized at 95 ° C for 4-30 hours. After crystallization, the finished sodium-cesium zeol is filtered from the mother liquor, washed off with alkali and water and dried at 100 -150 ° C-. Approx. 1. To 100 ml of sodium silicate solution (concentration on silica - 258.8 g / l) while stirring, pour 27.4 ml of aluminum sulphate with concentration on alumina - 89.3 g / l, 15.3 sodium aluminate ( alumina concentration - 200 g / l, sodium oxide - 303 g / l) and 39.3 ml of water. The chemical molar composition of the obtained basic alumina silica is as follows: 2.8Ka20 AlzOj 8510 160Н5.0. To this sodium alumina silica gel, 9.1 ml of sodium cerium silicon alumina silica gel were added, the composition of 0.7Cs20 12Har 12Si0 x X. The amount of gel formulation is 5.% by volume of the obtained basic sodium gel. The homogenized reaction mass is crystallized for 12 hours at 95 ° C. The resulting crystals are filtered, washed from the alkali with water, and dried at 100-150 ° C. The phase composition of the crystallization product: 100% sodium cesium zeolite. Water adsorption capacity 16 cwVr. The finished product has the following molar ratio of oxides: 0.032CsjC 3.45Na20 - X 8, is South 192.5} 1 gO. Primers are prepared as follows. 31.8 ml of sodium hydroxide with a concentration of 628.0 g / l are mixed with 6.49 g of cesium hydroxide dissolved in 19.9 ml of water, and 8.9 ml of sodium aluminate are added with stirring ((alumina concentration - 306 g / l, sodium oxide 277, 8 g / l) and 100 ml of sodium silicate with a silica concentration of 239 g / l. After sealing, a sodium-cesium gel seed of the following chemical composition is obtained: 0.8Cs, 0. IGKa.O. , 15Si0 x X 320H2.0. Example 2. A sodium silicate solution (concentration of silicon oxide - 220 g / l) is mixed with 16.7 ml of aluminum sulfate solution while stirring. with an alumina concentration of 86, 9 g / l, 12.3 ml of sodium aluminate solution with a concentration of alumina - 261.2 g / l, with sodium oxide - 298 g / l and 35.7 ml of water - chemical mole. The composition of the main alumina-silica obtained is the following: SCA. A1g0z-8g 0g-190H20 To the obtained sodium aluminum-silica gel add 16.6 ml of sodium-cesium alumina-silica gel with the following composition: 1 ,. 16Na20 .A.20z-1531 X The amount of sodium-cesium alumina silica gel is 10% by volume of the resulting basic gel. The reaction mass is crystallized for 12 hours at 95 s. The resulting crystals are filtered off, washed from the alkaline medium, dried at 100-150 C. The finished product contains 100% of crystals of sodium-cesium zeolite. Adsorption capacity for water 18, 5. The finished product has the following molar ratio of oxides: 0.08CSiO 4.31.Chf MgO, 8, X 203HjO. In tab. 1 shows the results of crystallization of sodium aluminosilicon with a different amount of seed.

The molar ratio of the main gel

Table 1

Phase composition of the crystallized product,%

3.2NfjO. AlgOjlOSiO

ZfSMa O. AljO, 8SiO. 160H20

SjZNa O .lOSiOj 200H2 0 3, ONajO 8SiO, 2, AljOj SSiOj, ISOHjiO

The optimal amount of seed is determined on the basis of X-ray phase analysis of crystallization products.

As can be seen from the table, the number of crystallization centers (seed 2-3% to 6%) negatively affects the phase composition of the synthesis products: the content of sodium-cesium zeolite decreases, the products of crystallization contain an impurity phase - chabasite: starting with the amount of seed equal to 5% by volume and above, 100% sodium cesium zeolite is obtained. Increasing the amount of seed over 15% by volume is impractical, for example 0.330 1 3.66 8.06 191.5 Prototype

By examples

Thus, it is the higher content of the crystalline phase of the zeolite that causes its high adsorption capacity.

47 sodium cesium zeolite + shabaz.it

95. sodium cesium zeolite + traces of chabazite + amorphous phase

100 sodium cesium zeolite

as the consumption of the expensive component in the composition of the zeolite increases.

Due to the fact that crystallization proceeds from a sodium gel using sodium cesium nuclei, it becomes possible to obtain cesium crystals with a lower cesium content and a certain position of the large cesium cation in the crystal lattice, thereby increasing the volume of the intracrystalline cavity and thereby achieving a large magnification of the adsorption capacity of absorbed products.

In tab. 2 presents data confirming the advantages of this method over the prototype.

Tablip, a 2

3.01

The proposed method for producing zeolites in polycation systems allows drastically reducing the consumption of 65 components — cesium hydroxide — for 60 cesium and 14.3%.

710669408

the expense of introducing it into the composition of the basics — according to the proposed method, for

sodium alumina silica, and in the process of adsorption requires the composition of sodium-deium gel - significantly lower amount of absorbent,

ki entered in the amount of 5-15%, which leads to a reduction in consumption

It provides significant savings in comparison with zeolite in various technologies with the prototype method, as the processes are extended, because of the higher adsorption of the zeolite adsorbenne capacity, the resulting yield is obtained.

Claims (1)

(54) (57) METHOD FOR PRODUCING. CESITA, including crystallization of alumina · gel in the presence of a seed gel of composition (0.6-1.0) Cs ₂ 0 ·. (10-16) Na ₂ 0 x A1 _g 0 ₃ (10-15) B10 _g · (200-300) H ₂ 0 at elevated temperature, washing and drying, characterized in that, in order to increase the adsorption capacity and reduce the cost of the process the crystallization is subjected to alumosilica gel composition (2.8-3 / 2) Na ₂ 0 · Α1 _ζ 0 ₃ · (8-10) Si0 ₂ x x (160-200) N _g O, and the gel seed is taken in the amount of 5- 15-06.%.