FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: invention relates to novel ruthenium catalysts, method for preparation thereof, and to employment thereof for catalytic hydrogenation of mono- and oligosaccharides in production of corresponding sugar alcohols. Ruthenium hydrogenation catalyst contains ruthenium supported by amorphous silica-based carrier, content of ruthenium being 0.2 to 7% of the weight of carrier, while carrier contains at least 90% silica and less than 10% of crystalline silicon dioxide phases. Catalyst is prepared by single or multiple treatment of carrier material with halogen-free solution of low-molecular weight ruthenium compound and subsequent drying of treated material at temperature not lower than 200°C immediately followed by reduction of dried material with hydrogen at 100 to 350°C. Herein disclosed is also a process for liquid-phase production of sugar alcohols (excepting sorbitol) via catalytic hydrogenation of corresponding mono- and oligosaccharides in presence of proposed catalysts.
EFFECT: increased activity and selectivity of catalysts.
16 cl, 4 tbl, 7 ex
The present invention relates to novel ruthenium catalysts, method of their production and to their use for the catalytic hydrogenation of mono - and disaccharides in obtaining sugar alcohols with the exception of sorbitol.
Industrial receiving sugar alcohols, normally carried out by catalytic hydrogenation of the corresponding mono - and disaccharides (see N. Schiweck et al. "Sugar Alcohols" in Ullmann''s Encyclopedia of Industrial Chemistry, 5-th ed. on CD-ROM). With this purpose long as catalysts used primarily Nickel catalysts, for example Nickel catalysts on a carrier or Raney Nickel. At various times it was also reported about the use for this purpose ruteniysoderzhaschim catalysts. Typically, we are talking about the so-called ruthenium catalysts on a carrier containing ruthenium on an oxide or organic medium such as coal.
Thus, in U.S. patent US 4380680, US 4487980, US 4413152 and US 4471144 describes catalysts for the hydrogenation of carbohydrates to the corresponding sugar alcohols containing ruthenium on stable under hydrothermal conditions, the material of the carrier. As the hydrothermal material carriers proposed alpha aluminiumoxid (US 4380680), titanium dioxide (IV) (US 4487980)treated tetrachloride titanium (IV) oxide, aluminum (US 4413152) and theta-aluminum oxide (US 4471144).
From U.S. patent US 4503274 known for the catalytic hydrogenation of carbohydrates to the corresponding sugar alcohols, received application (impregnation) is stable under hydrothermal conditions of the carrier with an aqueous solution of ruthenium halide and subsequent hydrogenation of the solids at a temperature in the range from 100 to 300°C.
In U.S. patent US 3963788 describes ruthenium catalysts for the hydrogenation of carbohydrates, in which the ruthenium supported on a carrier of the special zeolite-based binder. In U.S. patent US 3963789 as a carrier for ruthenium catalysts are available crystalline aluminosilicate clays, particularly montmorillonite.
In the application for French patent FR-A 2526782 describes the use of ruthenium chloride, obtained by the interaction of sodium chloride and ruthenium with the formation of Na2RuCl6to obtain a ruthenium catalyst on a carrier of silica for the hydrogenation of mono - and oligosaccharides.
Known in the art ruthenium catalysts exhibit in the hydrogenation of carbohydrates only moderate reactivity, resulting in achievable output per unit time per unit volume of sugar alcohols in terms of the used catalyst is small. Therefore, due to the high cost of ruthenium efficiency of this method leaves much to be desired. In addition, the selectivity of the catalyst is insufficient, resulting in the required supplementary what's the cost allocation of the target product. In particular, one often observes the epimerization of the hydroxyl groups.
Therefore, the present invention is the problem of obtaining new high reactivity of catalysts for production of sugar alcohols by the catalytic hydrogenation of the corresponding carbohydrates. In addition, the catalysts should have a high selectivity relative to the product that is not the last value from the point of view of continuous registration of the hydrogenation process.
This problem was suddenly solved ruthenium catalysts, we obtain:
i) single or multiple handling of the material of the carrier on the basis of amorphous silicon dioxide halogen-free aqueous solution of low molecular weight compounds of ruthenium and subsequent drying of the treated material carrier at a temperature below 200°S, preferably less than or equal to 180°and especially less than or equal to 150°C;
ii) recovery obtained in (i) solid hydrogen at a temperature in the range from 100 to 350°C, preferably from 150 to 350°and especially from 200 to 320°C;
and stage ii) is conducted directly after stage i).
Consequently, the invention relates to these catalysts, as well as described here the way they are received. The catalysts according to the invention have a high act is the want to make and high selectivity with respect to the product under hydrogenation of mono - and oligosaccharides.
Assume that the high reactivity of the catalysts according to the invention can lead to a particularly good distribution of the ruthenium on the surface of the material media and largely to the absence of halogen in material media. In accordance with the conditions of receiving the ruthenium is in the catalysts according to the invention in the form of a metallic ruthenium. Electron-microscopic studies (THEMES) of the catalysts according to the invention show that the ruthenium is in the material of the carrier in an atomically dispersed form and/or in the form of particles of ruthenium, which almost exclusively, i.e. more than 90%, preferably more than 95% in terms of the number of visible particles are in the form of atomized particles with diameter less than 10 nm, especially less than 7 nm. In other words, the catalyst, essentially, does not contain, that is, contains less than 10%, especially less than 5% of particles of ruthenium and/or agglomerates of particles of ruthenium with a diameter of more than 10 nm. In addition, due to the use of halogen-free precursors of ruthenium and solvent upon receipt of the catalyst chlorine content in the catalysts according to the invention is less than 0.05 wt.% (less than 500 parts per million) calculated on the total weight of the catalyst. Here and in all subsequent parts understand how mass parts, unless otherwise noted.
Significant aspects the ohms of the catalysts according to the invention is the use of the material of the carrier based on amorphous silicon dioxide. The term "amorphous" in this context mean that the content of the crystalline phases of silica is less than 10% of the material medium. Used for preparation of catalysts according to the invention the material of the carrier may, of course, to have a supramolecular structure, which is formed by a regular arrangement of pores in the material medium.
As the material of the carrier can be used, in principle, all kinds of amorphous silicon dioxide comprising at least 90% of silicon dioxide, and the remaining 10 wt.%, preferably not more than 5 wt.% from the material of the carrier may be also other oxide substances, such as magnesium oxide (MgO), calcium oxide (Cao), titanium dioxide (TiO2), zirconium dioxide (ZrO2), iron oxide (Fe2O3) and the oxide of the alkali metal. Needless to say that the material used media also halogen-free, that is, the content of halogen is less than 500 parts per million, calculated on the total weight of the material medium. The material of the carrier preferably contains not more than 1 wt.% and especially not more than 0.5 wt.% and especially not contain any measurable amounts (less than 500 parts per million) of aluminum oxide on the aluminum oxide. According to one preferred options use the Ute material of the carrier, containing less than 500 parts per million of iron oxide (Fe2About3). The content of alkali metal oxide, as a rule, dependent on the receipt of material media and could be up to 2 wt.%. Often it is less than 1 wt.%. Also suitable media that do not contain alkali metal oxide (less than 0.1 wt.%). The content of oxides of magnesium, calcium, titanium dioxide or zirconium can be up to 10% by weight of material of the carrier and is preferably not more than 5 wt.%. However, suitable materials media that does not contain any measurable amounts of these metal oxides (less than 0.1 wt.%).
Preferred are materials carrier having a specific surface ranging from 50 to 700 m2/g, especially in the range from 80 to 600 m2/g and especially in the range from 100 to 600 m2/g (BET surface according to DIN 66131). Among the powdery material carriers especially preferred such materials are media-specific (BET) surface which is from 200 to 600 m2/year of material media in the form of molded bodies specific surface is mainly in the range from 100 to 300 m2/year
Suitable amorphous materials media based on silicon dioxide are known to a person skilled and commercially available (see, for example, OW Florke, "Silika" in Ullmann's Encycloedia of Industrial Chemistry, 5-th ed. on CD-ROM). They can be of natural origin and can be produced artificially. Examples of suitable amorphous materials carriers based on silicon dioxide are diatomaceous earth, silica, pyrogenic silicic acid, precipitated silicic acid. In one of the preferred embodiments of the invention, the catalysts contain as materials of the silica carrier.
Depending on the design of the hydrogenation process, in which the use of the catalysts according to the invention, the material of the carrier may have a different shape. Because the method is executed as the suspension process for the preparation of catalysts according to the invention usually use material media in the form of fine powder. The powder is mostly particle size in the range from 1 to 200 μm, especially from 1 to 100 μm. When using the catalyst in a fixed bed usually use a molded body from a material carrier, obtained by extrusion, continuous profile extrusion or pelletizing and having the form of, for example, beads, tablets, cylinders, rods, wire harnesses, rings or hollow cylinders, stars and the like. The sizes of these particles typically vary from 1 to 25 mm is Often used catalyst bundles with a diameter of 2 to 5 mm and a length of from 2 to 25 mm
The content of ru is to be placed in the catalysts according to the invention can vary within wide limits. As a rule, it is at least 0.1 wt.%, mostly, at least 0.2 wt.% and often does not exceed 10 wt.%, accordingly, in terms of mass of material media, and to calculate the elemental ruthenium. The content of ruthenium is preferably in the range from 0.2 to 7 wt.% and in particular in the range from 0.4 to 5 wt.%.
To obtain ruthenium catalysts according to the invention the first material of the carrier is treated with halogen-free aqueous solution of low molecular weight compounds of ruthenium, in the following called the predecessor (ruthenium), thus to cause a desired amount of ruthenium in material media. This stage is in the following called impregnation. Thereafter, the thus treated carrier is dried at observance of the above-mentioned upper temperature limit. If necessary, the thus obtained solid substance is then treated with an aqueous solution of the ruthenium precursor and again dried. This process is repeated until, until absorbed by the material of the carrier, the number of compounds of ruthenium may not reach the desired content of ruthenium in the catalyst.
The treatment or impregnation of the material of the carrier may be carried out by various methods and is determined in a known manner by the type of material media. For example, the material of the carrier signal is to opryskivatel solution predecessor or dip into it or suspendibility in it. For example, the material of the carrier may suspendibility in an aqueous solution of the ruthenium precursor and after a specified period of time filtered water from sludge. Then the content of ruthenium in the catalyst can be easily adjusted absorbed amount of liquid and the concentration of ruthenium in the solution. The impregnation of the material of the carrier may also be carried out, for example, so that the medium is treated with a certain amount of an aqueous solution of ruthenium precursor, corresponding to the maximum amount of liquid that can absorb the material media. To this end, the material of the carrier may, for example, opryskivatel desired amount of liquid. Suitable devices are devices that are typically used for mixing liquids with solids (see Vauck/Müller, Grundoperationen chemischer Verfahrenstechnik, 10. Edition, Deutscher Verlag für Grundstoffindustrie, 1994, p. 405 ff.), for example, a dryer for crumbs of polymer drum to seal, drum mixer, grabowy mixer and the like. The monolithic carrier is usually sprayed with an aqueous solution of the ruthenium precursor.
Used for impregnation of aqueous solutions according to the invention do not contain Halogens, that is, they either do not contain or contain less than 500 parts per million by weight, preferably less than 100 parts per mi the Lyon halogen, calculated on the total weight of the solution. So as precursors of ruthenium use only such compounds that do not contain chemically bound halogen and sufficiently soluble in aqueous solvent. These include, for example, nitrosylated ruthenium (III) (Ru(NO)(NO3)3), acetate, ruthenium (III), as well as ruthenate (IV) alkali metals, such as ruthenate sodium and potassium.
The term "water" means in this water, and a mixture of water with up to 50 vol.%, preferably not more than 30 vol.% and, in particular, not more than 10 vol.% one or more miscible with water and organic solvents. For example, mixtures of water with alcohols with 1-4 carbon atoms, such as methanol, ethanol, n-propanol or isopropanol. Often use water as the only solvent. To stabilize the ruthenium precursor in the solution is an aqueous solvent often contains additionally at least one halogen-free acid, for example nitric acid, phosphoric acid, sulfuric acid or acetic acid, mainly halogen-free mineral acid. In many cases, as a solvent for the precursor ruthenium is used diluted with water halogen-free mineral acid, for example dilute to policecontributing nitric acid. The concentration of the ruthenium precursor in aq is x the solution is determined in a natural way, required for the application amount of the ruthenium precursor and absorption (absorbing) the ability of the material of the carrier with respect to aqueous solution is in the range from 0.1 to 20 wt.%.
Drying may be carried out by conventional means of drying solids in compliance with the above-mentioned temperature range. Compliance with the upper limit of the drying temperature according to the invention is important from the point of view of quality, i.e. the activity of the catalyst. The excess above the maximum drying temperature leads to an apparent loss of activity. The calcination of the carrier at an elevated temperature, for example above 300°or even 400°S, as suggested in the prior art, is not only unnecessary, but also adversely affects the catalyst activity. To achieve sufficient drying rate it, as a rule, is carried out at elevated temperature, for example at least at 40°and especially, at least at 70°and, in particular, at 100°s or greater.
Drying the impregnated ruthenium precursor solids are generally carried out at normal pressure, and to accelerate drying can also be used in low pressure. Often to accelerate drying over to be drying material through or direct the gas flow, such as airflow or azo is A.
The drying time naturally depends on the desired degree of drying and the drying temperature is generally in the range of 2 to 30 hours, mainly in the range from 4 to 15 hours.
Drying of the treated material media, mainly, hold up until the content of water or liquid components of the solvent before restoring ii) reaches a value of less than 5 wt.%, especially less than 2 wt.% and most preferably not more than 1 wt.% in terms of the total weight of solids. The mass percentages relate to the weight loss of solids determined at a temperature of 300°C, a pressure of 1 bar and a duration of 10 minutes. In this case, the activity of the catalyst according to the invention can be increased further.
Drying is preferably carried out while moving treated with a solution of precursor solids, for example by drying of solids in a rotary tube furnace or in a rotating ball of the furnace. The activity of the catalysts according to the invention can be further enhanced.
Translation obtained after drying of the solid in its catalytically active form of exercise according to the invention by hydrogenation of a solid substance in a known manner when the above temperature (stage ii)).
This material is of osites brought into contact with hydrogen or with a mixture of hydrogen and inert gas at the above temperature. The partial pressure for the recovery of secondary importance and, as a rule, varies from 0.2 to 1.5 bar. Often the hydrogenation of the material of the catalyst is carried out in a current of hydrogen at normal pressure of hydrogen. Hydrogenation is predominantly carried out at the motion obtained in stage i) solids, for example by hydrogenation of solids in a rotary tube furnace or in a rotating ball of the furnace. Thanks to the activity of the catalysts according to the invention can be further enhanced.
After hydrogenation to improve the manipulation of the catalyst can be passivated in a known manner, for example short-treated oxygen-containing gas such as air, preferably, however, an inert gas mixture containing from 1 to 10 vol.% the oxygen.
The catalysts according to the invention can be used as hydrogenation catalysts in many hydrogenation reactions, including hydrogenation of the double bond: C=C, C=O and C=N, and hydrogenation of the triple bonds: C≡C and C≡N.
Needless to say, used in this way catalysts with the weakening of their activity can be regenerated by methods conventional for the catalysts based on noble metals. If this can be called, for example, treatment of the catalyst with oxygen, as described in Belgium patent shall BE 882279, the processing of the diluted halogen-free mineral acid according to U.S. patent US 4072628 or treatment with hydrogen peroxide, for example, in the form of an aqueous solution with a concentration of from 0.1 to 35 wt.% or processing of other oxidants, mainly in the form of a halogen-free solutions. Usually after reactivation and before reusing the catalyst is washed with a solvent, for example water.
Therefore, the invention relates also to a method for producing sugar alcohols by the catalytic hydrogenation of the corresponding mono - and oligosaccharides, especially mono - and disaccharides in aqueous phase in a heterogeneous ruthenium catalyst, wherein the heterogeneous ruthenium catalyst is chosen from among ruthenium catalysts according to the invention except for the method of producing sorbitol (= sorbitol), which is the object of a parallel application 10128203.6.
Suitable sugars include, in principle, all known tetrose, pentoses, hexose and heptose and even as an aldose and a ketose, and their di - and oligosaccharides with the exception of glucose, fructose, gulose and sucrose, as in the hydrogenation of them is formed sorbitol. To monosaccharides that can be used in the method according to the invention, include, for example, erythrose, threose, ribose, arabinose, xylose, lyxose, allose, altrose, mannose, gulose, m is oz, galactose, talose, eritruloza, ribulose, xylulose, psychosis and tagatose as in D-form and L-form. Examples of disaccharides are maltose, isomaltose, lactose, cellobiose and melibiose. Mono - and oligosaccharides can be used as such or as mixtures. Preferably educti used in its pure form.
As suitable for the method for hydrogenation according to the invention the mono - and oligosaccharides should especially be called monosaccharides: mannose - for mannitol, galactose for receiving dulcita (Galactica) and xylose - to obtain xylitol, preferably D-form of monosaccharides and disaccharides: maltose - for maldita, isomaltulose (palatinose) - for isomaltitol and lactose - for Loctite. However, other named mono - and oligosaccharides can be subjected to hydrogenation in the presence of ruthenium catalysts according to the invention with the corresponding sugar alcohols. While hydrogenation of aldos leads to the production of sugar alcohols having the same configuration relative to the hydroxyl Oh-groups, which has used sugar, and hydrogenation of furans, as a rule, leads to the production of mixtures of two diastereoisomeric sugar alcohols, differing only in the configuration of carbon atoms, which furanose contains carbonyl fu the Ktsia. The selection of specific pure sugar alcohols from this mixture, as a rule, is possible without any problems.
The hydrogenation carried out mainly by hydrogenation of a solution of a specific mono - or oligosaccharides in aqueous solvent. The term "water" should be understood as defined above.
Water it is advisable to use as the sole solvent containing, if necessary, a small amount mainly halogen-free acid to regulate the pH. Preferably use a mono - or oligosaccharide in the form of an aqueous solution with a pH value ranging from 4 to 10 and especially from 5 to 7.
The concentration of doctow in the aqueous phase, in principle, you can choose arbitrarily. Often it is in the range from 10 to 80 wt.%, preferably in the range from 15 to 50 wt.% in terms of the total weight of the solution.
Very hydrogenation using catalysts according to the invention is usually carried out analogously to known methods hydrogenation of sugar alcohols, as described in the initially described prior art. For this purpose, liquid containing educt phase is brought into contact with the catalyst in the presence of hydrogen. In such a case, the catalyst may be suspended in the liquid phase hydrogenation (suspension the th process), any liquid can be passed through a fluidized bed of catalyst (process with fluidized catalyst) or through a fixed bed of the catalyst (catalytic process with a fixed catalyst). This hydrogenation can be carried out on a continuous or periodic process. Preferably the method according to the invention is carried out in reactors with irrigation according to the process with a fixed bed of the catalyst. While hydrogen can be passed as parallel towards the solution is subjected to hydrogenation educt and countercurrent through the catalyst.
Suitable apparatus for effecting the hydrogenation in the suspension process, as well as for the hydrogenation in the fluidized bed of catalyst and on the fixed catalyst bed is known from the prior art, for example, from Ullmann′s Enzyklopädie der Technischen Chemie, 4. Edition, Band 13, p. 135 ff., and P.N.Rylander "Hydrogenation and Dehydro-genation" in Ullmann′s Encyclopädia of Industrial Chemistry, 5-th ed. on CD-ROM.
Typically, the hydrogenation is carried out at an elevated pressure of hydrogen, for example at a partial pressure of hydrogen of at least 10 bar, mostly, at least 20 bar and especially at least 40 bar. Typically, the partial pressure of hydrogen does not exceed 500 bar, particularly 350 bar. Most preferably, if the partial pressure of the hydrogen content is designed in the range from 40 to 200 bar. The reaction temperature typically is at least 40°and often does not exceed 250°C. Preferably the hydrogenation process is carried out at a temperature in the range from 80 to 150°C.
Due to the high activity of the catalyst requires a relatively small amount relative to the educt. So, when periodic suspension process, typically use less than 1 mol.%, for example, from 10-3mol.% to 0.5 mol.% ruthenium, calculated on 1 mole of sugar. Continuous hydrogenation process passed through the catalyst usually subject to hydrogenation educt in the amount of from 0.02 to 2 kg/l (catalyst) × h) and preferably in quantities of from 0.07 to 0.7 kg/(l (catalyst) × h).
The following examples serve to more detailed explanation of the invention:
I. receiving the catalysts according to the invention
1 Order: powdered, halogen-free catalyst, not calcined.
A certain amount of a specific material carrier impregnated with a maximum amount of solution in water nitrosylated ruthenium (III), which could be absorbed by a given material media. The maximum amount of solution absorbed by a specific material of the carrier was determined beforehand by means of authentic samples. Con is entrely solution was chosen in each case such in order to obtain the desired concentration of ruthenium in the material medium.
Then, the thus obtained solid substance was dried in a drying Cabinet at 120°C for 13 hours. The residual water content was less than 1 wt.% (determined by weight loss of the sample after drying it at 300°and a pressure of 1 bar for 10 minutes).
The thus obtained solid substance was recovered in the reaction tube in a stream of hydrogen at 300°and normal pressure for 4 hours. After cooling and passivation of nitrogen, the catalyst was passivatable by adding 5 vol.% oxygen in nitrogen for a period of time of 2 hours.
2. Prescription: powdered, halogen-free catalyst, dried in a mobile state, not calcined.
The receipt of the catalyst was carried out analogously to the instructions, but the drying was performed in a rotating ball dryer. The residual water content was less than 1 wt.%.
3. Prescription With: powdered, halogen-free catalyst calcinated.
The receipt of the catalyst was carried out analogously to the directions In, but after drying the obtained solid substance before hydrogenation was heated in a stream of air up to 400°C for 4 hours.
4. Prescription D: powdered, halogen-free catalyst, not calcined.
Received the e of the catalyst was carried out analogously to the prescription, but instead of nitrosylated ruthenium (III)used chloride, ruthenium (III).
5. Prescription E: having the form of a harness, halogen-free catalyst, not calcined.
A certain number of cylindrical bundles of material media (diameter 4 mm, length from 3 to 10 mm) was impregnated with a maximum amount of solution in water nitrosylated ruthenium (III), which could be absorbed by the material of the carrier. Absorbed by each material carrier maximum amount of solution was determined beforehand by means of authentic samples. The concentration of the solution in each case was chosen to obtain the desired concentration of ruthenium in the material medium.
Then, the thus obtained impregnated strands were dried at 120°C for 13 hours in a rotating ball of the furnace. The residual water content was less than 1 wt.%.
Thus obtained dried Assembly was restored in a rotating ball of the furnace in a stream of hydrogen at 300°under normal pressure for 4 hours. After cooling and passivation in a stream of nitrogen thus obtained catalyst was lasciviously by adding 5 vol.% oxygen in nitrogen for a period of time of 2 hours.
|The catalyst is.|
|Catalyst No.||The content of ruthenium [wt.%]||Prescription||Media|
|V-a comparative catalyst|
|1)the diatomaceous earth powder with a content of SiO2more than 99.95 wt.%, the specific BET-surface 523 m2/g, a water absorption of 1.4 ml/g, pore volume 0.75 ml/g (specific nitrogen parametria according to DIN 66134), defined pore size 60Å, particle size of from 63 to 200 μm;|
|2)powder of alpha-alumina with soda is the content of Al 2About3more than 99.95 wt.%, the specific BET-surface 7 m2/g, a water absorption of from 0.84 ml/g, particle size less than 100 microns;|
|3)powder theta-aluminum oxide with a content of Al2About3more than 99.95 wt.%, the specific BET surface 80 m2/g, a water absorption of 1.05 ml/g, a pore volume of 0.67 ml/g (according to DIN 66134), particle size less than 100 microns;|
|4)the powder of titanium dioxide with a content of TiO2more than 99.9 wt.%, the specific BET-surface 325 m2/g, a water absorption of from 0.84 ml/g, particle size less than 63 µm;|
|5)the wiring diatomaceous earth (d 4 mm; L from 1 to 10 mm) of diatomaceous earth with the content of SiO2over 99.5 wt.% (Na2O 0.3 wt.%), the specific BET-surface 162 m2/g, a water absorption of 0.95 ml/g, a pore volume of 0.7 ml/g (according to DIN 66134).|
II. Hydrogenation of xylose by the suspension process (Examples 1 and 2, comparative examples V1 to V5)
The General prescription for the hydrogenation of:
Into the autoclave with a volume of 2.5 l with a stirrer, a device for sampling and maintaining the pressure of hydrogen was loaded with 1200 ml of 30 wt.% solution of xylose in water together with 3 g of a specific catalyst. The autoclave was inititially nitrogen. Then escalate hydrogen to a pressure of 100 bar and heated autoclaves up to 90°C. the reaction was carried out re eshiwani with the intensity of 1000 rpm To determine the degree of conversion during the reaction were regularly sampled and determined the content of xylose, xylitol and other products by high-performance liquid chromatography (HPLC). The reaction was interrupted not later than 10 hours. Table 2 shows the time required to achieve maximum yield. The selectivity towards the formation of xylitol, which can be determined with an accuracy of about 0.5% (absolute).
|Example||Catalyst No.||Media||t-max [h]||The degree of conversion [%]||Selectivity [%]|
|1||K1||SiO2powder||3||99,85||more than 98,5|
|V1||K2(V)||SiO2powder||7||99,85||more than 98,5|
|2||KS||SiO2powder||5||at 99.95||more than 98,5|
|V2||K4(V)||SiO2powder||10||of 99.96||more than 98,5|
|V4||K6(V)||θ-Al2About3powder||10||99,53||more than 98,5|
The test results show that the catalysts according to the invention have better reactivity and better selectivity in comparison with catalysts not according to the invention.
III. Hydrogenation of mannose. maltose and lactose in the suspension process (Examples 3, 4 and 5)
Similarly indicated in II General instruction to the hydrogenation was subjected to hydrogenation 1200 ml of 30 wt.% solution specific mono - or disaccharides in water together with 3 g of a specific catalyst under hydrogen pressure of 50 bar and a temperature of 120°C. the Degree of conversion and selectivity were determined as described in II, by high performance liquid chromatography (HPLC). Table 3 shows the time required to achieve the maximum degree of conversion (more than 99.8 per cent). The selectivity towards the formation of the desired sugar alcohols.
|Example||Catalyst No.||Educt||Product||t-max [h]/td>||The degree of conversion [%]||Selectivity [%]|
|3||K1||mannose||mannitol||2||more and 99.8||96|
|4||K1||maltose||▫ maltitol||1||more and 99.8||69|
|5||K1||lactose||lactic||3||more and 99.8||87|
IV. Hydrogenation of xylose and lactose on the fixed catalyst bed (Examples 6 and 7)
The reactor was heated reaction tube made of stainless steel, filled with a catalyst K8. The reaction apparatus was forcing the pump to educt, circulating pump, a device for sampling and settling tank (separator) with height adjustment of the level and regulation of exhaust gases.
In this reaction, the plant was subjected to circulation 30 wt.% solution specific mono - or disaccharides at a temperature of 100°and at hydrogen pressure of 50 bar, with a speed of 50 ml/(g (catalyst) × h) and in the process determined analytically, as described in II, the decrease in the amount of educt, the growth of the product and the formation of by-products. Upon reaching the degree of conversion of 99.4% of the reaction was interrupted. Table 4 shows the time contact is the formation, required to achieve the maximum degree of conversion, together with selectivity.
Contact time = volume (solution)/volume (reaction tubes) × the reaction time.
|Example||Educt||Product||Contact time [h]||Selectivity [%]|
1. Ruthenium catalyst for the hydrogenation of mono - and oligosaccharides containing ruthenium on a carrier based on amorphous silicon dioxide, obtained
i) single or multiple handling of the material of the carrier on the basis of amorphous silicon dioxide halogen-free aqueous solution of low molecular weight compounds of ruthenium and subsequent drying of the treated material carrier at a temperature below 200°C;
ii) recovery obtained in (i) solid hydrogen at a temperature in the range from 100 to 350°C;
and stage ii) is conducted directly after stage i), and the content of ruthenium in the catalyst is from 0.2 to 7 wt.% in terms of material media, and the material is of osites based on amorphous silicon dioxide is at least 90 wt.% silicon dioxide, calculated on the material of the carrier, and contains less than 10 wt.% phases of crystalline silicon dioxide.
2. Ruthenium hydrogenation catalyst according to claim 1, in which the material of the carrier on the basis of amorphous silicon dioxide has a BET surface ranging from 50 to 700 m2/year
3. Ruthenium hydrogenation catalyst according to claim 1, containing ruthenium in an amount of from 0.4 to 5 wt.%.
4. Ruthenium hydrogenation catalyst according to claim 1, in which the material of the carrier on the basis of amorphous silicon dioxide contains less than 1 wt.%, aluminum oxide calculated at Al2About3.
5. Ruthenium hydrogenation catalyst according to claim 1, and used in stage (i) a compound selected from ruthenium nitrosylated ruthenium (III)acetate, ruthenium (III), routedata (IV) sodium and potassium.
6. Ruthenium hydrogenation catalyst according to claim 1, and the solid obtained in stage i) and used to restore the on stage ii)has a moisture content less than 5 wt.% in terms of the total weight of solids.
7. Ruthenium hydrogenation catalyst according to claim 1, and drying at stage i) is carried out at the movement of the treated material media.
8. Ruthenium hydrogenation catalyst according to one of claims 1 to 7, consisting of
the material of the carrier on the basis of amorphous silicon dioxide and
elementarmagneten, located on the carrier in an atomically dispersed form and/or in the form of particles of ruthenium,
moreover, the catalyst, in the main, does not contain ruthenium particles and/or agglomerates with diameters larger than 10 nm, and the total halogen content is less than 0.05 wt.% in terms of the total weight of the catalyst.
9. The method of obtaining ruthenium hydrogenation catalyst according to one of claims 1 to 8, characterized in that it comprises the following stages:
i) single or multiple material handling media based on amorphous silicon dioxide halogen-free aqueous solution of low molecular weight compounds of ruthenium and subsequent drying of the treated material carrier at a temperature below 200°C;
ii) recovery obtained in (i) solid hydrogen at a temperature in the range from 100 to 350°C;
and stage ii) is conducted directly after stage i).
10. The use of ruthenium hydrogenation catalyst according to one of claims 1 to 8 when receiving sugar alcohols by the catalytic hydrogenation of the corresponding mono - and disaccharides, with the exception of obtaining sorbitol.
11. The method of obtaining sugar alcohols by the catalytic hydrogenation of the corresponding mono - and oligosaccharides in the liquid phase heterogeneous ruthenium catalyst, except for the method of producing sorbitol, featuring the the action scene, what a heterogeneous ruthenium catalyst selected from ruthenium hydrogenation catalysts according to claims 1-8.
12. The method according to claim 11, wherein the mono - or oligosaccharide used in the form of an aqueous solution having a pH ranging from 4 to 10.
13. The method according to claim 11, characterized in that the hydrogenation is carried out at a partial pressure of hydrogen in the range from 10 to 500 bar.
14. The method according to claim 11, characterized in that the hydrogenation is carried out at a temperature in the range from 40 to 250°C.
15. The method according to one of § § 11 to 14, characterized in that the hydrogenation is conducted in a fixed bed of catalyst.
16. The method according to one of § § 11 to 14, characterized in that the hydrogenation is carried out in the liquid phase containing the catalyst in the form of suspension.
FIELD: chemical technology.
SUBSTANCE: invention relates to a method for preparing alkaline- and thermostable composition based on sugar alcohols of the optical density less or equal to 0.100 in S-test. Method involves treatment of sugar-base composition with strong-base anion-exchange resin in hydroxide form at temperature 30-100°C. Method provides decreasing consumption of chemical reagents and providing carrying out the combined a single-step process for alkaline stabilization and decolorizing.
EFFECT: improved preparing method.
18 cl, 7 tbl, 8 ex
FIELD: chemical industry; method of production of the alkali-resistant and thermal-resistant polyols.
SUBSTANCE: the invention is pertaining to the improved method of production of the alkali- resistant and thermal-resistant polyols representing the sugar-alcohol syrups. The method provides for the following stages: hydrogenation of the hydrolysate of the corresponding polysaccharide with formation of the hydrogenated sugar-alcohol syrup, the alkaline and thermal treatment of the hydrogenated syrup for production of the stabilized sugar-alcohol syrup, refining of the stabilized sugar-alcohol syrup by its gating through, at least, one ion-exchange resin, in which the stabilized sugar-alcohol syrup is refined by means of its double gating through the cationic- anionic ion-exchange configuration (CACA) including, at least, the first weak-acid cationic ion-exchange resin and the second strongly-base, medium-base or weak-base anion-exchanging resin. The method allows to have the alkali-resistant and thermal-resistant polyols not having the shortcomings of the polyols of the previous level of the engineering.
EFFECT: the invention ensures production of the alkali-resistant and thermal-resistant polyols not having the shortcomings of the polyols of the previous level of the engineering.
18 cl, 3 ex, 1 dwg
FIELD: chemical technology.
SUBSTANCE: invention relates to a method for synthesis of 1,3-propanediol involving the following steps: (a) formation of aqueous solution of 3-hydroxypropanal; (b) hydrogenation of 3-hydroxypropanal to form crude mixture of 1,3-propanediol, water and cyclic acetal of molecular mass 132 Da (MW 132 cyclic acetal) and/or cyclic acetal of molecular mass 176 Da (MW 176 cyclic acetal); (c) distillation (drying) of indicated crude mixture of 1,3-propanediol for water removing and formation of the second crude mixture of 1,3-propanediol (the first flow of residues after distillation) containing 1,3-propanediol and MQ 132 cyclic acetal and/or MW 176 cyclic acetal; (d) contact of the flow containing MW 132 cyclic acetal and/or MW 176 cyclic acetal with acid-base cation-exchange resin or with acid zeolite, or with soluble acid, and (e) removal of MW 132 cyclic acetal. Method provides enhancing effectiveness for extraction and purification of 1,3-propanediol.
EFFECT: improved method of treatment.
10 cl, 9 tbl, 1 dwg, 6 ex
FIELD: industrial organic synthesis and catalysts.
SUBSTANCE: invention relates to a method for processing of butanol-butyl formate fraction obtained in propylene hydroformylation process, which method comprises reduction of butanol-butyl formate fractions with hydrogen at 200-280°C, pressure 1-30 atm, and volumetric feedstock and hydrogen supply rate 0.1-0.5 and 50-500 h-1, respectively. Reaction is carried out on catalyst having following chemical analysis, wt %: copper oxide 48.0-63.0, zinc oxide 9.0-18.1, chromium oxide 19.0-34.8, graphite 1.0-5.1 and activity index below 40 to form butyl alcohols and carbon oxide as final products. Method allows using real non-diluted butanol-butyl formate fractions and achieving following results: conversion of butyl formates 94.5-99.5%, content of methanol and high-boiling products in hydrogenate 0.8-1.5 and 2.9-3.5%, respectively.
EFFECT: enhanced process efficiency.
4 tbl, 2 ex
FIELD: methods of production of 1.3 alkandiol.
SUBSTANCE: the invention is pertaining to the field of chemical industry, in particular, to production of 1.3 alkandiol by hydrogenation of the raw material, containing 3-hydroxyaldehyde at presence of a catalyst and a source of hydrogen, where as a source of hydrogen use a synthesis gas, and the catalyst represents a heterogeneous catalyst containing copper on the carrier; and also to the method of production of 1.3-alkandiol by conversion of an oxide in the process including a hydroformylation and hydrogenation. At that it is not obligatory to realize the indicated phases simultaneously in one reaction vessel. The reached technical result consists in essential reduction of the fixed value of equipment and in bringing to a "single-phase" production of 1.3-propandiol (or a similar 3-alcandil) from ethylene oxide (or a corresponding oxide).
EFFECT: the invention ensures essential reduction of the fixed value of equipment and reduction to a "single-phase" process of the propandiol or alkandiol production.
9 cl, 2 tbl, 2 ex
FIELD: organic chemistry, in particular production of high oxoalcohols.
SUBSTANCE: invention relates to method for production of high oxoalcohol from isomeric olefin mixture containing from 5 to 24 of carbon atoms. Claimed method includes hydroformylation in presence of catalyst at elevated temperature and elevated pressure. Hydroformylation in carried out in one step, and ones-through olefin conversion is limited in range of 40-90 %. Obtained reaction mixture after catalyst separation is preferably transferred to selective hydration carrying out at 120-220°C and pressure of 5-30 bar in presence of supported catalyst containing copper, nickel and chromium as active ingredients. Hydration product mixture is separated by distillation, and olefin fraction is recycled into hydroformylation step. As starting materials for hydroformylation mixtures of C8-, C9-, C12- or C16-olefins are used.
EFFECT: high olefin conversion ratio, selectivity, and capability.
15 cl, 1 dwg, 1 tbl, 2 ex
FIELD: organic synthesis catalysts.
SUBSTANCE: invention relates to catalyst for aromatization of alkanes, to a method of preparation thereof, and to aromatization of alkanes having from two to six carbon atoms in the molecule. Hydrocarbon aromatization method consists in that (a) C2-C6-alkane is brought into contact with at least one catalyst containing platinum supported by aluminum/silicon/germanium zeolite; and (b) aromatization product is isolated. Synthesis of above catalyst comprises following steps: (a) providing aluminum/silicon/germanium zeolite; (b) depositing platinum onto zeolite; (c) calcining zeolite. Hydrocarbon aromatization catalyst contains microporous aluminum/silicon/germanium zeolite and platinum deposited thereon. Invention further describes a method for preliminary treatment of hydrocarbon aromatization catalyst comprising following steps: (a) providing aluminum/silicon/germanium zeolite whereon platinum is deposited; (b) treating zeolite with hydrogen; (c) treating zeolite with sulfur compound; and (d) retreating zeolite with hydrogen.
EFFECT: increased and stabilized catalyst activity.
26 cl, 1 dwg, 5 tbl, 4 cl
FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: invention is dealing with development of effective catalyst for hydrogenation of unsaturated hydrocarbons (alkenes, alkynes) and a method for preparation thereof, which could be used in fine organic synthesis. Catalyst contains palladium compound and a modifying additive, the former being palladium bis-acetylacetonate and the latter phosphine (PH3) at molar ratio ranging from 1:0.1 to 1:1, respectively. Preparation of catalyst is based on reduction of palladium compound with hydrogen in presence of phosphine, which is introduced before reduction of palladium bis-acetylacetonate at catalytic system formation temperature: 70-80°C. Optimal time for molding of catalyst is 10-15 min.
EFFECT: increased catalytic activity when carrying out catalytic process under mild conditions (at room temperature and atmospheric pressure) and reduced catalyst preparation expenses.
2 cl, 5 tbl, 24 ex
FIELD: petrochemical process catalysts.
SUBSTANCE: invention relates to preparation of supported Fischer-Tropsch catalysts and comprises treatment of supported Fischer-Tropsch catalyst precursor in the first step, which precursor is in pre-reduced state in the form of particles. Precursor contains cobalt-impregnated catalyst support and reducible labilized cobalt oxide in fired state selected from compounds depicted by formulas including CoOaHb, wherein a=1.7 and b>0, and monometallic hydrocalcite-type compounds Coii 0,74Coiii 0,26(OH)2,01(NO)0,21(CO)0,02×0,6H2O. Cobalt oxide is reduced with reducing gas, which is pure hydrogen, at the first volumetric velocity of supplied gas SV1 and first heating velocity HR1 to form partially reduced catalyst precursor. Resulting precursor is activated, in the second step, with reducing gas, which is pure hydrogen, at the second volumetric velocity of supplied gas SV2 and second heating velocity HR2, so that SV2<SV1 and/or HR2≥HR1 provided that, when SV2=SV1, then HR2≠HR1 and, HR2=HR1, then SV2≠SV1.
EFFECT: achieved maximum catalytic activity.
12 cl, 3 dwg, 5 tbl, 5 ex
FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: invention provides copper and silica-based catalyst containing 22.5-53.0% copper. Catalyst is prepared by reductive thermal decomposition of copper silicate in hydrogen flow at 380-450°C. catalyst is used in dihydroxyalkane production processes carried out at 180-200°C.
EFFECT: increased activity and selectivity of catalyst.
3 cl, 1 tbl, 8 ex
FIELD: hydrocarbon conversion processes.
SUBSTANCE: process consists in catalytic decomposition of hydrocarbon-containing gas at elevated temperature and pressure 1 to 40 atm, catalyst being reduced ferromagnetic cured product isolated by magnetic separation from ashes produced in coal combustion process at power stations. The catalytic product represents spinel-type product containing 18 to 90% iron oxides with balancing amounts of aluminum, magnesium, titanium, and silicon oxides. Prior to be used, catalyst is subjected to hydrodynamic and granulometric classification.
EFFECT: reduced total expenses due to use of substantially inexpensive catalyst capable of being repetitively used after regeneration, which does not deteriorate properties of original product.
2 cl, 6 ex
FIELD: petroleum processing and petrochemistry.
SUBSTANCE: catalytic system of hydrocarbon feedstock hydrofining is activated by circulating hydrogen-containing gas or mixture thereof with starting feedstock through layer-by-layer loaded catalysts in presulfided or in presulfided and oxide form at elevated temperature and pressure. Hydrogen is injected into circulating hydrogen-containing gas or mixture thereof with starting feedstock portionwise, starting concentration of hydrogen in circulating hydrogen-containing gas not exceeding 50 vol %. Starting feedstock consumption is effected stepwise: from no more than 40% of the working temperature to completely moistening catalytic system and then gradually raising feedstock consumption to working value at a hourly rate of 15-20% of the working value. Simultaneously, process temperature is raised gradually from ambient value to 300-340°C. Circulating factor of hydrogen-containing gas achieves 200-600 nm3/m3. Addition of each portion of hydrogen is performed after concentration of hydrogen in circulating hydrogen-containing gas drops to level of 2-10 vol % and circulation of hydrogen-containing gas through catalysts loaded into reactor begins at ambient temperature and further temperature is stepwise raised. Starting feedstock, which is straight-run gasoline or middle distillate fractions, begins being fed onto catalytic system at 80-120°C.
EFFECT: enabled prevention and/or suppression of overheating in catalyst bed.
5 cl, 6 tbl, 12 ex
FIELD: petrochemical processes.
SUBSTANCE: feedstock is brought into contact with preliminarily activated zeolite-containing catalyst, namely mordenite-supported Pt, at 250-300°C, pressure 1.5-3.5 MPa, hydrogen-containing gas-to-feedstock ratio 300-1000 nm3/m3, and feed flow rate 1.0-4.0 h-1. Preliminary activation of zeolite-containing isomerization catalyst is conducted in two successive steps: drying catalyst in inert gas flow; reducing catalyst in hydrogen-containing gas flow; and supplying feedstock and setting steady-state isomerization process. Drying of zeolite-containing catalyst in inert gas flow is effected under conditions of gradually raised temperature from 120°C at temperature raise rate 10-15°C/h and ageing for 2-5 h at 120°C to 350°C followed by ageing at this temperature, whereupon temperature is lowered to 130°C. Reduction of zeolite-containing catalyst in hydrogen-containing gas flow is effected at gradually raised temperature to 220-350°C at temperature rise rate 15-25°C/h and ageing for 2-6 h at 220-350°C, whereupon temperature is lowered to 180°C. Initial feedstock is supplied at 180°C in circulating hydrogen-containing gas flow, aged for 4 h at 180°C and then gradually heated to 250°C at heating rate 5°C/h, after which further heated at heating rate 5°C a day to achieve process characteristics meeting product quality requirements.
EFFECT: increased catalyst activity, selectivity, and working stability.
2 cl, 2 tbl, 17 ex
FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: palladium-containing hydrogenation catalyst, which can be used to control rate of autocatalytic hydrogenation reactions, is prepared by hydrogen-mediated reduction of bivalent palladium from starting compound into zero-valence palladium and precipitation of reduced zero-valence palladium on carbon material, wherein said starting material is tetraaqua-palladium(II) perchlorate and said carbon material is nano-cluster carbon black. Reduction of palladium from starting compound and precipitation of zero-valence palladium on carbon material are accomplished by separate portions.
EFFECT: increased catalytic activity, enabled catalyst preparation under milder conditions, and reduced preparation cost.
1 dwg, 1 tbl, 12 ex