SU810263A1 - Method of producing boron phosphate catalyst for n-butyl alcohol - Google Patents

Description

In addition, when an ammonia solution of a mixture of orthoboric and orthophosphoric acids in liquid nitrogen (bp -196 ° C) is sprayed, the solution freezes rapidly. Such rapid freezing allows uniform distribution of the reactive components and consequently improves the quality of the catalyst. Subsequent removal of water from the cryogranule obtained in this way by sublimation in vacuum at (-60) - (- 80) ° C makes it possible to avoid undesirable polymerization processes (formation of chains P-O-P and B-O-B), which was not possible Achieve none of the previously known approaches.

Example 1. A 7% ammonia solution of borophosphoric acid, containing 112.6 g of orthophosphoric acid (concentration 87.5%) and 62 g of orthoboric acid, is sprayed with nitrogen under a pressure of 0.3-0.5 atm. The obtained granules of the frozen solution are separated by filtration, sublimated in a vacuum chamber at a pressure of 10 mm Hg. Art. It is used for 20 hours and then subjected to heat treatment in a vacuum oven at 50 ° C for 5 hours.

The resulting product has a particle size of 0.5-1.0 m. M, a bulk density of 0.10 g / cm1. In the IR spectra of the crystal framework of the product described in Example 1, along with bands 550-650 and 970-100, characteristic for vibrations of B-O-B and P-O-P bonds in the structure of BPO, bands of 1400–1460 cm –– were observed, which are characteristic of stretching vibrations of NH + –ONES in the structure of the catalyst.

Example 2. The borophosphate catalyst prepared according to Example 1 is heat treated at 200, 400, 600, 800 ° C for 2 hours at a temperature. The obtained samples have a particle size of 0.3-0.5 mm.

The characteristics of the samples of boron phosphate catalysts of BPO4, obtained by the cryochemical method (Kp), are given in Table. one.

In the IR spectra of the crystal framework of catalysts 1-4 described in example 2, only the bands 550– 650, 940–1100 belonging to the vibrations of В-О-В and Р-О-Р bonds in the ВРО4 structure are observed.

In the IR spectrum of sample L5 (prototype), along with the bands belonging to the BP04 structure itself, bands 790 and 1200 were found, characteristic of vibrations of polyborate and polyphosphate chains in the BPO4 structure, as well as a wide band 1440-1500, belonging to the vibrations of the amino group in the structure of the catalyst.

Thus, the use of the cryochemical method results in obtaining a borophosphate catalyst of a certain stoichiometric composition having a specific particle size distribution. The compounds described in examples 2-4 can be used as and selective catalysts for the process of n-butapol dehydration in butane-1.

Example 3. 0.2 g of a sample of borophosphate BP (Kp) -0.5-4, obtained under the conditions of Example 2 at 400 ° C, is placed in a 500 mm long steel reactor and heated at 280 ° C in a current of helium (v 35 ml / min). Then 2.4 µl of n-butanol was introduced into the reactor. Analysis of the reaction products is carried out chromatographically. The total degree of conversion of n-butanol into reaction products is 75%; the composition of the gaseous reaction products,%: butets-1 95; butene-2-cis 1.5; butene-2-trans 3.5 (no by-products).

Example 4. Under the conditions of Example 3, the catalytic activity of sample BP (Kr) -0.5-6, obtained as in Example 2 at a heat treatment temperature of 600 ° C, is determined. The degree of conversion of n-butanol into reaction products is 90%, the composition of the gaseous reaction products,%: butene-1 95; butene-2-cis 1,3; butene-2-trans 3.7.

Example 5. Under the conditions of Example 3, the catalytic activity of sample BP (Kp) -0.5-8 is determined, obtained as described in

Table 1 Example 2, at a heat treatment temperature of 800 ° C. The degree of conversion of n-butanol into reaction products is 35%, the composition of the gaseous products,%: butene-1 61; butene-2-cis 30; buten-2-trans 19. Example 6. Under the conditions of example 3, it is defined. The catalytic activity of sample BP-b (amm) (prototype) is given. The degree of conversion of n-butanol into reaction products is 26%, the composition of the gaseous products. ten-1 94; butene-2-cis 1.7; butene-2 trans 4,3. The data in examples 1-6 show that the proposed method of preparation allows to obtain borophosphate: a catalyst of a certain stoichiometric and granulometric composition, exhibiting high activity and selectivity. The data on the comparative assessment of the catalytic activity of borophosphate and industrial catalysts in the model reaction of n-butyl alcohol dehydration are given in table. 2. Table J buforma of the invention 1. A method for preparing a borophosphate catalyst for dehydrating n-butyl alcohol, comprising mixing equimolar amounts of orthoboric and orthophosphoric acids in an ammonia solution and a heat treatment, characterized in that, in order to obtain a catalyst in the form of granules with increased activity and selectivity, the resulting mixture of acids in an ammonia solution is sprayed into a liquid nitrogen medium, followed by sublimation of the resulting cryogranules in a vacuum. 2. The method of p. 1, t vT and h and y and the fact that the catalyst is heat treated at 50-SOO C. Sources of information taken into account in the examination I. Patent Germany L 882700, cl. 12 to 19/01, published. 1953. 2. Patent of France No. 1344333, cl. At 01 J, pub. 1963. 3.E. Gruner “Phosphates and arsenates of trivalent elements, section I:“ Hydrated forms of borophosphate and boroarsenate; 1) Borophosphate, its hydrated form and borophosphoric acid. - J. anorg und allg chemie, 219, 1934, p. 181 (prototype).

Claims (2)

Claim 1. A method of preparing a borophosphate catalyst for the dehydration of n-buty- 5 of alcohol, including mixing equimolar amounts of orthoboric and orthophosphoric acids in an ammonia solution and heat treatment, characterized in that, in order to obtain a catalyst in the form of grapules with increased activity and selectivity, the resulting mixture of acids in an ammonia solution is subjected to atomization of liquid nitrogen with subsequent sublimation of the obtained cryogranules in vacuo15 Uma. 2. The method π π. 1, with the fact that the heat treatment of the catalyst is carried out at 50-800 ° C.