SU983047A1 - Zeolyte adsorbent production process - Google Patents

Description

(54) METHOD OF OBTAINING ZEOLITE ADSORBENT

12

This invention relates to methods for the preparation of silica silicate mineral sorbents, in particular low silicon zeolites for use as a component of synthetic detergents (SMS). 5-2.0;: 20-50) at a temperature above the product yield, is 140150.

The disadvantage of this method is low product yield.

The closest to the proposed technical essence and the achieved result is a method for preparing a zeolite sorbent (type A zeolite), which includes the crystallization of alkali aluminum silica from a mixture of 2.5-6.0 NajO A1203-, 0.5-5.0 6-200 HjO at 90 ° C. The solution is drained at.

Sodium-potassium, evy product is obtained from the sodium form by the exchange of 25% KCi solution at 80-90 ° Ci Amount of CaO sorbed in terms of anhydrous zeolite 172-182 mg / g 2 .. .i

The disadvantage of the known method is the impossibility of directly obtaining a sorbent active in calcium from alkaline alumina silicates containing significant amounts of potassium, therefore for long. obtaining the sodium-potassium product after crystallization is carried out at the stage of ion exchange.

The purpose of the invention is to simplify and reduce the cost of the method.

The goal is achieved by a method for preparing a zeolite adsorbent, including an alkaline

15 silicate solution with aluminum to obtain aluminum silica gel and its crystallization at elevated temperature, the mixing being carried out by adding alkaline silicate solution to an aluminate solution at a speed of 20-300 to obtain a molar ratio of the components equal to 0.70-1.25 in the aluminum silica gel / Al C equal to 25 1.65-2.48, and crystallization is carried out at 65-85 ° C.

When the order of draining of the solutions changes, the temperature and the draining rate increase, a cobalt-like phase is formed, at lower temperatures and speeds it lengthens the duration of the process of obtaining a mineral sorbent and crystals of a uniform size are formed. With an increase in the molar ratio of oxides in the aluminum silica, a sodalite-like phase is formed, while the value decreases, the yield and utilization rate of the raw material during crystallization decreases, and the t value cannot be achieved for technical reasons (to obtain a concentrated aluminate solution).

In the optimal mode of implementation. In this method, odorous crystals of a round product with a diameter of 2-5 µm are formed. Calcium (by CaO) is 110-140 mg / g of air-dry sorbent (direct analysis of the product after sorption) or in terms of anhydrous product 145-18.0 mg / g . A high value of calcium sorption is achieved even at 20 ° C over 5 mi ", contact | as compared with the sodalitic product by a known method (20 mg / g).

On the radiograph obtained according to the proposed method mineral sorbent has some similarities with zeolite A, and the chemical composition is similar to aluminate sodalite, May. %: Me O 10-21; KjO 2-12 / AIjOj 26-31; 510228-33, i.e. has (LOomul 1.1-1.2 X 1.6-1.73, which is different from zeolite A.

Crystallization of alumina silica of the proposed composition at 80 ° G ends in 3-5 hours. The product yield is 160-300 kg / m of alumina. To prepare the original alumina silica gel, an aluminate solution is used, having a caustic modulus 4-2.3, a concentration of 1.8-5.5 mol / L and an amount of potassium KjjiOiZIheIoO not more than 0.30 mol and an alkaline silicate solution ( silicate lumps having a concentration (NagO) of 1-2 mol / l and a silicon modulus m 1.0-4.0. The optimum volume ratio of aluminate and silicate solutions is 1: 3-3: 1.

Claims (2)

Example. An aluminate solution is introduced into a plastic jar with a crack and a mixer, and a silicate solution is added to it with Continuous agitation at the indicated rate (Filtered liquid glass solution). From the starting solutions and their ratio are given in the table. The total volume of solutions (alumina silicon) 1 l. The alumina-silica gel is stirred at 20 ° C for 10 minutes, after which the heating in the thermostat begins. Duration of heating up to 80-90 ° С 40-60 minutes. The composition of the resulting alumina silicates and crystallization conditions are given in the table. The precipitate, after washing with hot water, is dried at 120 ° C. The proposed method of obtaining a mineral aluminosilicate sorbent has the following advantages in comparison with the known method. To obtain a calcium sorbent active (110-150 mg CaO / g air-dry product) for CMC, alkaline technical solutions containing potassium, for example, obtained from the processing of alumina raw materials, can be used, which reduces the cost of production. Since for alkali and aluminum the cost of the sorbent in the known methods is 55-60%, then reducing their cost by 2 times when using technical products will reduce it by 40, and by producing 100 thousand tons per year will save 4-5 million . rub. A high yield of the product (up to 300 kg / g) is achieved, with a decrease in the duration of the temperature and the process, which increases the productivity of the process and reduces the production cost. The mineral sorbent is obtained in the form of crystals in the same way. One size I 1-5 microns) with rounded corners, which reduces the mechanical and nose of the fabrics during washing. The resulting mineral sorbent has, in contrast to the sodalite product, high kinetics during calcium sorption at low temperatures {mg CaO / g; : t, 5 min 52 (24J, 20 min 65 (28), t-90 ° C, 5 min 111 U5), 20 min 120 (95) (in brackets. l of sodalite product). Thus, the product does not differ in quality from that obtained in a pure sodium aluminosilicate system. The simplification of the method with respect to the known is achieved because the stage of exchange of ionic Na to K becomes unnecessary, the solutions merge at room temperature, i.e. without heating. Claim 1. A method for preparing a zeolitic adsorbent, comprising mixing an alkaline silicate solution with an aluminate solution to produce alumina silica and crystallizing it at the same level (; the aluminate solution until the alumina silica gel has a molar ratio of the components of SiOa / ABiOa equal to 0.70-1.25, and equal to 1.65-, 48, and crystallization is carried out at 65-85 C. 2. Method POP1, characterized in what's the tide The alkaline silicate solution is brought to the aluminate solution at a speed of 20-300 l / mea-min. Sources of information, taken into account during the examination 1. Germany patent No. 2722535, class C 01 B 33/28, 1978. 2. The patent of Germany No. 2531342, cl. C 11 O 3/12, 1977.