RU2381210C2 - Technology of industrial synthesis of glyoxal from monoethylene glycol using industrial silver catalyst deposited on aluminosilicate, containing 32-36 wt % silver - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: present invention relates to a method for synthesis of glyoxal in form of an aqueous solution containing 40 ± 1.5 or 30 ± 0.8 wt % glyoxal which can be used as an emulsifier, bacterial inhibitor, flocculant, preservative, solvent etc. The method involves oxidative dehydrogenation of monoethylene glycol on a domestically produced industrial silver catalyst deposited on aluminosilicate, containing 32-36 wt % silver of the D-53M type, and involves the following successive steps: preparation of a 40-50 wt % aqueous solution of monoethylene glycol on distilled water or steam condensate; preparation of initial reaction mixture by mixing air or nitrogen-air mass, heated in an electrical heater to 260°C or above, and a water-glycol vapour phase obtained in an evaporator and superheated in a "hardening" apparatus using heat of the oxidation reaction mass, taken in respective molar ratios: monoethylene glycol O2=1.0:1.0-1.1; monoethylene glycol: N2=1.0:4.36-7.0; - synthesis of glyoxal in a single- or multiple-shell reactor operating in adiabatic mode, on a catalyst layer at temperature 540-620°C, atmospheric pressure and specific input of ethylene glycol of 1.70-2.3 g/cm³ cat·h; - strengthening of the oxidate (synthesis reaction mass) which is raw glyoxal through vacuum stripping at temperature not above 52°C and residual pressure of 100 mm Hg to obtain commercial grade product containing 40 ± 1.5 or 30 ± 0.8 wt % glyoxal.

EFFECT: proposed method can be used in industrial production.

2 dwg

Description

Technology for the industrial production of glyoxal (GOA) from monoethylene glycol (EG) using an industrial silver-supported catalyst containing alumina silicate containing 32-36 wt.% Silver.

The chemistry of the process. Oxidative dehydrogenation of EG with atmospheric oxygen in the vapor phase, related to the field of fine organic chemistry.

Development Goal. The creation of an industrial technology for the production of this unique chemical reagent, which the country does not yet have, correspondingly also produces and, as a result, glyoxal (GOA) in the form of a 40% aqueous solution is imported from Germany and China (at a cost of 2500 Euro / t) [ one].

Scope of GOA: as an emulsifier, bacterial inhibitor, flocculating agent, preservative, solvent, additive to building cement, in pesticides, deodorants, cosmetics, photography, fire fighting, rubber, polymers, synthetic resins, woodworking, embalming mixtures, products and tobacco, etc. .d.

A description of several cases of attempts to obtain dialdehydes using silver catalysts, with the deposition of silver on carriers, was previously described in a number of publications:

The source of information Process mode t, ° С; P - kgf / cm ² Ag catalyst / carrier EG conversion, wt.% The yield of glyoxal (GOA), wt.% GOA removal with cm ³ cat-mg mg / sec Izv. AN ser. Chem. p. 641-643, 1964 600; - 32% Ag / γ-Al ₂ O ₃ - 20,0 0.007 Japanese Patent Pub-Lication, 48160 / '92 -; ^- 10% Ag / γ-Al ₂ O ₃ 98.0 65.0 0,0333 Journal of Catalysis, No. 142'729'734,1993 550; - Ag / SiC (silicon carbide); also, with 200 ppm phosphate NH ₄ in terms of phosphorus 98.5 73.0 6.25 · 10 ^-5 - - 7.22 · 10 ^-5 Japanese Patent Publication No. 10570 / '78 (comparative patent) 40% Ag / γ-Al ₂ O ₃ - 48.3 * 0.36 *) a high content of synthesis impurities in the product: acetol-2.4 wt.%; acetic aldehyde - 8.2 wt.% Tech. mileage report op.-pr. installation "Glyoxal-200" OJSC "Omsk rubber", 22-28. 2004.2004 530 ÷ 0.04 ÷ ÷ 610; ÷ 0.07 34% Ag / Aluminosilicate Δ83.6; including 69% of the values were 94.915 wt.% Δ 62.27 **; including 78% of the values were 66.08 wt.% Δ 0.336 mg, including max - 0.38, min - 0.287 mg / cm ³ cat · s **) impurities other than EG _ost glydealdehyde, 2.1% wt, no.

The need for a process. Creation of domestic industrial production with a capacity of 2.5 thousand tons per year of glyoxal in the form of a 30-40 wt.% Aqueous solution. At first, it was only the development of a “technology” for the production of glyoxal according to the synthesis scheme being developed by creating a Glioksal-100 semi-industrial unit according to the initial data for its design, developed by KEMEKO LLC (Reutovo, Moscow Region) under agreements financed by the plant [ 2, 3, 4]. The working draft was completed by the PKO of the plant [5] with delivery on February 27, 1997 for sale on the industrial site of the previously decommissioned department for the disposal of organochlorine compounds of the I 45th unit of acetaldehyde of shop 6-6 _{a, b} in accordance with the order of the General Director of Omsky rubber "[6]. Acquisition was carried out using equipment, instrumentation and automation equipment available at the plant, with the delivery of two missing equipment positions (dosing pumps - 2 units; air electric heaters - 2 units).

The installation was adopted by the commission (act dated 03.06.99.); commissioning was delayed until 10/15/99 due to the need for a radical reconstruction of air heaters with spiral heating elements. Then the "epic" began with a series of "start-stop-start" mixed up with systematic reconstruction of equipment and equipment, improvement of the technological scheme of individual units and, in general, studies of operational parameters and methodological and analytical support of the process. In total, the installation in the mode of experiments and synthesis was 5783 hours lasting from several to tens of days, including 5-day run (at the insistence of the Kameko management, from September 3 to September 7, 00) with a "mini-reactor" welded into the contact apparatus (d _int = 8.3 cm, h = 5 cm) [8] with loading of the catalyst into it in the volume of 276 cm ³ (with regime parameters close to the “Initial data”: from the calculation - 2.38 mg EG / cm ³ cat · s; T = 600 ± 5; in anticipation of the recommended data: EG conversion: 97%; selectivity glyoxal 65-67 wt.%). However, the process went into uncontrollability mode, respectively, and the results: EG conversion: 59.33 ÷ 67.73%; glyoxal selectivity - 12.614 ÷ 42.2%; glycolaldehyde - 5.77 ÷ 11.82%; contact time - 0.011 ÷ 0.0212 sec; the linear velocity of the reaction mixture is from 2.4 to 4.745 m / s. Due to the lack of the ability to reproduce the “Initial Data”, the “mini-reactor” was dismantled, the contact apparatus was restored to its original form, and work began on the search for effective normative parameters of the production process necessary for the design of an industrial plant [9]. The last (31st) of the series - the 160-hour run was completed on July 28, 04, with the availability of available raw materials, and the installation was stopped to perform a set of works ensuring its stable continuous operation with the removal of the initial data to scale the process.

During the experimental runs of the installation, the following was revealed: the glyoxal content in the composition of the oxidate (a product of EG dehydrogenation) under conditions of a stable temperature synthesis is higher when the heat load is shifted below the middle catalyst layer; the conversion of ethylene glycol is higher when the heat load is shifted to the upper layers of the catalyst (see Fig. 1 is a diagram of the thermal field in the catalyst layer "Ag - aluminosilicate").

Therefore, the ratio h: d = 1: 3.45 of the reactor issued in the Design Baseline for this process turned out to be unacceptable and it was brought, as the experiment progressed, to 1.75: 1.0 - in particular, the 34th run Glyoxal-200 installations. And it is not the last option.

As you know, when choosing the type of reactor, the adiabatic heating of the reaction mixture during the process is most important, which is understood as the following:

ΔТ _hell = (ΔH _p ) · C _o / C _p , where: ΔН _p - thermal effect of the reaction, kcal / mol; With _about - the initial concentration of the reagent, mol / m ³ mixture; With _p is the heat capacity of the reaction mixture, kcal / m ³ · deg.

It is also known that the reverse (longitudinal) movement of a gas-vapor mixture depends on a number of operating and structural parameters of the reactor: vapor velocity, particle size (grain) and free cross section of the catalyst, and the diameter of the reactor. In the case under consideration, in the adiabatic reactor of the isothermal process of oxidative dehydrogenation of ethylene glycol, the temperature monotonously increases and the maximum concentration of reagents is determined by the temperature of the onset of the reaction and the thermal stability of the catalyst [15], which are very important in industrial conditions.

Some thermodynamic characteristics of the main stages of the partial oxidation of EG in ethanedial on Ag catalysts.

(CH ₂ OH) ₂ + O ₂ → (CHO) ₂ + 2H ₂ +378.9 kcal / mol

(CH ₂ OH) ₂ - ^(-H) ₂ → (CHO) ₂ + 2H ₂ -34.6 kcal / mol

CH ₂ OH) ₂ + ^_5/2 O ₂ → 2CO ₂ + 3H ₂ O + 268.5 kcal / mol

(CHO) ₂ + ^_3/2 O ₂ → 2CO ₂ + H ₂ O + 187.5 kcal / mol

H ₂ + _^1/2 O ₂ → H ₂ O + 57.8 kcal / mol; and etc.

Description of the technological process and installation scheme (reconstructed, operating).

The technology for producing glyoxal in the form of 40 ± 1.5 and 30 ± 0.8 wt.% Aqueous solution consists of the following main stages:

- preparation of 40 ÷ 50 wt.% an aqueous solution of ethylene glycol;

- obtaining the reaction mixture (PC) in the mixer by supplying heated in an electric heater air or nitrogen-air mass and water-glycol vapor phase obtained in the evaporator and superheated in the quenching apparatus due to the heat of the reaction mass of oxidation, in appropriate proportions (as opposed to in the “Initial data” of a vapor-nitrogen-air-glycol mixture overheated in an electric furnace through BOT-high-temperature organic coolant);

- synthesis of glyoxal by the method of oxidative dehydrogenation with atmospheric oxygen in a one- (or many-) shelf reactor (depending on power) operating in adiabatic mode on a catalyst layer deposited on Ag aluminosilicate at a temperature of 540 ÷ 620 ° C and specific feeds of ethylene glycol 1 , 70 ÷ 2.3 g / cm ³ cat · hour; molar ratios: EG: O ₂ = 1.0: 1.0-4.1; EG: N ₂ = 1.0: 4.36 ÷ 7.0 (many researchers are of the opinion that the molar ratio of EG: N ₂ = 1.0: 10 is maintained. However, based on the presence of another diluent - water in the PC, concentration O ₂ in PC at the same time decreases proportionally and, as a result, it was revealed under the conditions of the installation runs that a lack of oxygen leads to the release of noticeable amounts of glycolaldehyde, which has the ability to immediately acetalize ethylene glycol to oxymethyldioxolane);

- strengthening of the oxidate to obtain a marketable product by evaporation of crude glyoxal under vacuum of 660 mm Hg-column and a temperature of not more than 52 ° C [t _cp water at P _ost = 102 mm Hg equal to 52 ° C];

- cleaning the exhaust air after the contact process in the column type apparatus;

- mixing and disposal of waste and wastewater with neutralization, if necessary;

- filling the product into containers (TU 38.402-62-163-97, amended on 02.07.02; License No. 35-EV-000874 (hk), 12.23.04).

The EG received from the supplier (in the railway or tank truck) is pumped into the tank (1) (V = 63 m ³ ) equipped with a metering device with an alarm system of max and min levels and a blocking device when it reaches the maximum position.

The preparation of an aqueous EG solution is carried out in two capacitive-type apparatuses (3 ₁ and 3 ₂ ) at a temperature of 50-60 ° C, heated by steam condensate heat - one through a jacket, the other through a coil; equipped with an alarm maximum and minimum levels of the solution (it is possible to prepare the EG solution continuously in the stream by regulating the automatic system in the mixer (6) in front of the evaporator (5)). The finished EG solution through the evaporator, heating to 180-200 ° C, enters the annulus of the quenching apparatus (8 ₂ ) of the synthesis products and with a temperature of 220-260 ° C enters a special apparatus (6) to mix with the heated in the electric heater ( 9 _1.2 ) by air or nitrogen-air flow, and the resulting reaction mixture enters the GOA synthesis contact apparatus (7). The reaction mass from the reactor (7) is subjected to "instant hardening" in the apparatus (8 _1,2 ) to a temperature not exceeding 90 ° C, enters the apparatus-phase separator (10), and from it into the raw glyoxal storage tank, then it is strengthened in a vacuum apparatus (12).

The evaporator (5) is heated through the annulus with medium-pressure steam (10-15 kgf / cm ² ) and is equipped with automatic steam flow control and regulation systems, as well as an alarm when the steam pressure drops. The installation is equipped with a steam condensate collector from which it is pumped into apparatuses (3 _1,2 ) (as well as into their jacket and coil) or into the flow of preparing the EG solution, and the annulus of the main contactless quenching apparatus (8 ₁ ), from there - to the jacket of the raw glyoxal evaporation apparatus (12), and the excess through the pressure regulator to the refrigerator, cooled by process water, and from it to the steam condensate collection tank or to the plant’s return condensate network. The unit has its own water distillation unit.

Compressed air and nitrogen for the installation come from the factory network through filters. The flow rate, temperature and pressure of the air supplied to the PC mixer are automatically controlled, an alarm is provided for the minimum pressure (in case of a decrease in its consumption, a blocking system is provided in the mixer to turn off the electric heater and the metering pump of the aqueous EG solution). In order to protect the reaction system from overpressure, the installation is equipped with a PPK that is triggered when the pressure reaches 0.7 kgf / cm ² . Under conditions associated with the commissioning of the installation, heating the catalyst bed in the reactor, the temperature of the air supplied to the mixer is maintained at a level of 400-600 ° C.

To control the contact time between the PC and the catalyst in the reactor (7), the temperature in it and in the mixer (6), the installation is equipped with an automatic system for supplying nitrogen to the reactor.

The team’s tying of the plant’s technological scheme with heat recovery from the reaction of glyoxal synthesis for overheating of an aqueous EG solution and during the evaporation of raw glyoxal in a vacuum apparatus (not more than 100 mm Hg.st. and temperatures not exceeding 52 ° C) is aimed at reducing energy costs, and lowering the temperature of the reaction mass of the synthesis by “quenching” prevents the occurrence of side reactions, thereby preserving the yield of the target product — glyoxal in the composition of the oxidate (Schematic diagram of the installation “Ch Ioxal-200 "- see figure 2).

Samples of an aqueous solution of glyoxal obtained during the experimental runs of the installation were sent to a number of organizations for research and the following reviews were received:

- ZAO Petrospirt: - glyoxal content - 38.4 wt.%; acidity - 1.45 (pH); [10];

- product of the company "BASF" - 39.5-40.4%; acidity - 2.0-3.5 (pH);

- 30.4% of the samples in the composition on the biocidal effect showed complete suppression of SVB (sulfate-reducing bacteria) with a concentration of 10 ⁸ -10 ⁹ cells / cm ³ [11];

- 40 and 30% solutions turned out to be suitable in the production of antimicrobial, antiviral, antifungal effects in the composition of a wide range of drugs "Glutar" [12];

- the effectiveness of using 30% glyoxal samples in the compositions of antiseptic and disinfectants in the treatment of surfaces of livestock buildings, which helps to reduce the incidence of animals [13];

- the effective action of product samples in the composition of tanning agents in the primary processing of reindeer skins in Syktyvkar [14].

In addition to developing the technology for obtaining this reagent and the initial data for the design of an aggregated capacity of 2.5 thousand tons per year for a commercial product, the experience of the experimental work carried out on the created Glyoksal-200 installation (essentially venture) provides professionally trained personnel for the industrial production for the skillful management of this very complex and delicate process of organic synthesis.

Information sources

1. Knyazev A.S. et al. Journal of Catalysis in Industry, No. 5, 2006, pp. 23-30.

2 Contracts: No. 7/92-94, 04/01/92 (49 million rubles); No. 11/93-94, June 91, 1994 (11.26 million rubles); No. 37/95 (4.5 million rubles)

3. Brodsky M.S. // BI No. 47, 1992. Patent Form. The method of producing glyoxal (stage oxidative dehydrogenation).

4. Sugakov V.V. Initial data for design. Glyoxal production from EG, 100 t / g. September 2, 1993

5. PKO OJSC "Omsk rubber" // Working draft No. 15651-TX. Glyoxal-200, May 22, 1996

6. Pariy V.Ya. Order for Omsk Rubber OJSC of 04.16.1997, No. 95, Omsk.

7. Khokhlov S.L. and others. Actual problems of chemistry and technology of organic substances. Yekaterinburg, ed. IOS UB RAS, 2002, p. 418-432.

8. FAX LLC "KEMEKO" dated 07/07/2000. Protocol of technical meeting dated 08/30/00. OJSC "Omsk rubber".

9. Sendel A.K. Protocol of the technical meeting of October 19, 2000, Omsk Rubber OJSC, Omsk.

10. Volkova S.V. The results of the analysis of glyoxal samples, ref. No. 8-93 dated 01/14/04. LLC "Petro-spirt", St. Petersburg.

11. Nikitina A.B. // Report dated 06/15/04. OJSC "Kuskovo Order" Badge of honor "chemical plant".

12. Farber V.L. // Report dated 06.06.06. ref. No. 22M, LLC "Rubicon", Vitebsk, Republic of Belarus.

13. Bazhin M.A., D.Sc., professor. // Report of the All-Russian Research Institute of Brucellosis and Animal Tuberculosis. Omsk, June 2007

14. Petrov L.A., D.Sc., professor // On the development of an effective tanning and preserving agent. IOS UB RAS, Yekaterinburg (correspondence since April 2006).

15. Beskov B.C., Flock V.K. Simulation of catalytic processes and reactors. M .: Chemistry. 1991 year

Claims (1)

Method for the industrial production technology of glyoxal in the form of an aqueous solution containing 40 ± 1.5 or 30 ± 0.8 wt.% Glyoxal by oxidative dehydrogenation of monoethylene glycol on a domestic silver-supported industrial catalyst containing 32-36 wt.% Silver, type D -53M, consisting of the following sequential technological stages:
preparation of a 40-50 wt.% aqueous solution of monoethylene glycol in distilled water or steam condensate;
obtaining the initial reaction mixture by mixing heated in an electric heater air or nitrogen-air mass (up to 260 ° C and above) and a water-glycol vapor phase obtained in an evaporator and superheated in a quenching apparatus due to the heat of the reaction mass of oxidation taken in the corresponding molar ratios : EG: 02 = 1.0: 1.0-1.1; EG: N2 = 1.0: 4.36-7.0;
synthesis of glyoxal in a single- or multi-cavity reactor operating in adiabatic mode, on a catalyst bed at a temperature of 540-620 ° C, atmospheric pressure and specific ethylene glycol feeds of 1.70-2.3 g / cm ³ cat · hour;
strengthening of the oxidate (reaction mass of synthesis), which is raw glyoxal, by vacuum evaporation at a temperature of not more than 52 ° C and a residual pressure of 100 mmHg to obtain a marketable product containing 40 ± 1.5 or 30 ± 0.8 wt .% glyoxal.

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