SU1137077A1 - Method for preparing type a zeolite containing manganese in its structure - Google Patents

Abstract

A method for producing a type A zeolite containing manganese in a structure, comprising mixing solutions of sodium silicate, sodium hydroxide, aluminum-containing compounds and manganese salts, hydrothermal treatment of the mixture, separation of the mother liquor, prrkv and drying of the product, a template, a separate template, a separate template, a template, a template, a template, a template, a template, a pattern, a sharpening solution, a separation of the mother liquor, a sodium hydroxide solution, a manganese salt, a manganese salt, a hydrothermal treatment of the mixture, separation of the mother liquor, sodium hydroxide, a manganese salt, manganese salt increase the purity of the zeolite, mix sodium silicate with sodium hydroxide, the mixture is kept for 1-3 hours, after which premixed solutions of aluminum and manganese chlorides are added to the mixture and before Drothermal treatment mixture is kept for 3-10 hours.

Description

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The invention relates to inorganic chemistry — the synthesis of zeolites and zeolite-like minerals, and can be used to produce zeolite catalysts and adsorbents, as well as for the production of aluminosilicate pigments colored with transition element ions. A known method for producing a zeolite consists in hydrothermal crystallization of a mixture of the molar composition: NaO-Al O-ja-lO; SiO "8-20; MOn / g 0.01-.5; Н „0 100-450, with 343433КЩ. The disadvantage of this method is the complicated process of preparing the reaction mixture, as well as the rather long crystallization time of the product. The closest to the proposed technical essence and the achieved result is a method for producing aluminosilicates of a zeolitic structure, which consists in hydrothermal treatment at 323-423 K of an aqueous reaction mixture obtained by mixing a silicon-containing substance, an aluminum component and a salt of one of the listed elements of groups IB, IA (except Hg), IW, IIIB, 111A (except B, A0, YIII; (except RU) or one of the rare-earth elements Thj V, Pb, Mn, in the separation of the mother liquor, washing the obtained product and drying it This method is characterized by heterogeneity of the reaction mixture, which is characterized by the presence of separately existing particles of aluminosilicate gel and metal hydroxide introduced into the structure. The heterogeneity of the reaction mixture leads to the presence in the final product of impurities of transition metal compounds, I. .... When synthesized by a known method of a type A zeolite containing manganese in the carcass, the presence of impurities is 8.5%. The purpose of the invention is to increase the yield and purity of the zeolite. The goal is achieved by the fact that according to the method of obtaining a type A zeolite containing manganese in the structure, including displacing solutions of sodium silicate, sodium hydroxide, aluminum-containing compound and manganese salt, hydrothermal treatment of the mixture, separating the mother liquor, washing and drying the product, mix sodium silicate with sodium hydroxide, the mixture is incubated. 1-3 hours, after which pre-mixed solutions of aluminum and manganese chlorides are added to the mixture and left before the hydrothermal treatment for 3-10 hours. Example .. The reaction mixture is prepared in ampoules as follows. Mix 21.3 ml of 6.1% sodium silicate solution (calculated as NanSiO ji-r 10.6 ml of 18.9% sodium hydroxide solution. Mix the mixture for 2 hours at room temperature, B prepared and kept a mixture of solutions of sodium silicate and sodium hydroxide is added a mixture of 3.8 ml of a 29.8% solution of aluminum chloride and 0.1 ml of a 26.5% solution of manganese chloride on the basis that the content of g-ions of manganese is 57, from total amount of g-ions of manganese and aluminum in the reaction mixture. The molar composition of the reaction mixture: SiO: (A170- + Mn ) 1, Na ,, 0: (A1,, 0, + + MpO) 7.4: 1 The reaction mixture was kept in a sealed ampoule for 7 hours at room temperature. The synthesis was carried out in an autoclave, where the ampoules with the reaction mixture, at 403 K for 2 hours. The product obtained is washed with distilled water using a vacuum pump and a Buchner funnel, and then dried. The synthesis product is an aluminum silicate of the zeolite structure, a type A zeolite, as indicated by lines 1.22; 0.871; 0, 0.55; 0.434; 0.408; 0.370; 0.340; 0.328; Oi298, 0.289; 0.274; 0.268; 0.262; 0.250; 0.245; 0.236; 0,223; 0.217; 0.213; 0,210; 0.207; 0,205 nm on the diffraction pattern. The resulting product has a solid color. The content of type A zeolite in the sample is 98.0%. Impurities (gel and a small amount of phillipsite-type zeolite) are 2%. Lines with interplanar distances 0,505; 0.386; 0.316; 0.269 nm refers to phillip.

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To determine the boundary values of the vyierzhki mixture of solutions of sodium hydroxide and sodium silicate, as well as the reaction mixture before the hydrothermal treatment were obtained reaction mixture, identical to the described example.

Data on the yield of the target product with a crystalline structure, in this case a type A zeolite, its purity, color, depending on the holding time of the mixture of sodium hydroxide and sodium silicate solutions and also depending on the exposure time, to the reaction mixture before the hydrothermal treatment is shown in the table.

The occurrence of the transition meter in the aluminosilicate framework of the zeolite structure is judged by the color and X-ray phase analysis data. When manganese enters the framework, flesh-colored samples are obtained. Manganese, which was not included in the framework, is observed in the form of impurities of black and brown colors.

The suggested exposure intervals for the mixture of sodium hydroxide and sodium silicate solutions, and the range of the reaction mixture before the hydrothermal treatment were selected from the conditions for obtaining the highest yield and purity of the aluminosilicate zeolite structure (type zeolite) containing the transition element. ,

When the mixture of sodium hydroxide and sodium silicate solutions is less than the suggested limit, i.e. at 0.5 h, the content of type A zeolite is 88.0%, and the impurities are 12%. An increase in the exposure time of more than 3.0 hours also leads to a decrease in the yield of the target product and an increase in the content of impurities. At the time of completion of the mixture of sodium hydroxide and sodium silicate solutions 3.5 hours

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the content of type A zeolite is 91.0%, and that of impurities is 9.0%.

As a result of determining the boundary values of the exposure time of the reaction mixture before the hydrothermal treatment, it has been established that. a reduction in less than 3 hours leads to a decrease in the yield of the target product. At top

the reaction mixture before the hydrothermal treatment of 2.5 hours, the content of type A zeolite is 91.0%, and impurities 9.0%. When the reaction mixture was over 10.0 h, the zeolite content

Type A is 98.3%, and impurities 1.7%. An increase in the reaction time of the reaction mixture before the hydrothermal treatment from 10 to 24 hours leads to an increase in the content of zeolite type

And in the sample at 2%, but an increase in the reaction time over 10 hours is not advisable.

Proposed method for producing aluminosilicates of zeolitic structure

containing transition elements, in comparison with the known, allows to increase the yield and purity of aluminosilicates of the zeolite structure containing transition elements. Use | For example, when preparing a type A zeolite containing manganese in the carcass, the yield of the desired product can be increased by 6.8% and the impurity content reduced to 1.7%.

In addition, the proposed method allows reducing the content of the transition element in the impurity composition. This is evidenced by obtaining a sample with a uniform solid color. Obtaining a white sample with black and brown inclusions of manganese compounds, which is observed upon receipt of a type A zeolite according to the prototype, is not a sign

the occurrence of manganese in the aluminosylate frame of the zeolitic lycate. ,,

The proposed method

Claims (1)

METHOD FOR PRODUCING TYPE A ZEOLITE CONTAINING MANganese B STRUCTURE, including mixing solutions of sodium silicate, sodium hydroxide, aluminum-containing compounds and manganese salts, hydrothermal treatment of the mixture, separation of the mother liquor, washing and drying of the product, characterized in that, in order to increase the yield and increase the purity of the zeolite, sodium silicate is mixed with sodium hydroxide , ¹ chennuyu obtained mixture was allowed to stand 1-3 hours, after which the mixture was added a premixed solution of aluminum chloride and manganese and prior to hydrothermal treatment mixture was incubated 3-10 hours. (60 1 1137077 2