RU2731459C1 - Reactivated hydrotreating catalyst - Google Patents

Abstract

FIELD: technological processes.SUBSTANCE: invention relates to a reactivated hydrofining catalyst for diesel fuel, comprising, wt.%: Mo – 10.0–16.0; Ni – 2.5–4.5; P – 1.2–2.4; S – 6.7–10.8; γ-AlO– balance, obtained by sulphurisation of mixture containing complex compounds Ni(CHO), H[Mo(CHO)O], H[PNiMoO]; H[Ni(OH)MoO], H[PMoO] and a carrier comprising γ-AlO, sulfur in form of sulphate anion SO, phosphorus in form of phosphate anion PO, in following concentrations, wt.%: Ni(CHO) – 8.8–15.6; H[Mo(CHO)O] – 3.2–8.0; H[PNiMoO] – 5.8–11.6; H[Ni(OH)MoO] – 3.7–7.1; H[PMoO] – 3.0–7.4; carrier – balance; wherein carrier comprises wt.%: SO– 0.5–2.5; PO– 2.5–5.5; γ-AlO– balance.EFFECT: disclosed catalyst determines optimum surface concentration of active component and optimum particle morphology, minimizes undesirable reaction of active metals with carrier surface, which leads to formation of compounds with low activity in catalysis, enables to hydrotreatment of raw material with high content of secondary fractions, provides good access of molecules of raw materials to be converted to an active component, allows to produce diesel fuel containing not more than 10 ppm of sulfur at low starting temperatures of the process, which allows prolonging the catalyst service life.1 cl, 2 tbl, 4 ex

Description

SUBSTANCE: invention relates to regenerated and reactivated hydrotreating catalysts intended for obtaining low-sulfur diesel fuel.

Currently, most of the commercial Russian diesel fuels contain no more than 10 ppm of sulfur in accordance with the EURO-5 and Russian standards [GOST R 52368-2005 (EN 590: 2009). Diesel fuel EURO. Specifications]. Obtaining low-sulfur fuels is achieved by deep hydrotreating of diesel fractions with a degree of desulfurization of at least 99%. In recent years, the share of secondary fractions containing in high concentrations difficult to convert sulfur compounds, organo nitrogen compounds and condensed aromatic compounds has been increasing in the hydrotreating feedstock. To process such raw materials, it is necessary to increase the pressure of the hydrotreating process and switch to supported nickel-molybdenum catalysts, NiMo / Al ₂ O ₃ , which have an increased hydrogenating and denitrogenating ability compared to traditional cobalt-molybdenum systems.

During operation, catalysts, including NiMo / Al ₂ O ₃ , are inevitably deactivated, mainly due to blocking of the surface with carbonaceous deposits (coke), and need to be regenerated. With the oxidative removal of coke from modern highly active Ni-Mo hydrotreating catalysts of the latest generations, it is possible to restore their activity by no more than 90%, which is insufficient for the reuse of catalysts in the processes of obtaining diesel EURO-5 fuels. In this regard, it is necessary to develop regenerated deep hydrotreating catalysts with an activity of at least 99% of that of fresh catalysts.

As a rule, oxidative regeneration is carried out in devices that exclude local overheating of the catalyst, as described in [M. Marafi, A. Stanislaus, E. Furimsky. Handbook of spent hydroprocessing catalysts - regeneration, rejuvenation and reclamation, Elsevier BV, Amsterdam, 2010. P. 362.]. It is possible to use tunnel belt ovens [C. Vuitel, NPRA Ann. Meeting, Oct. 8-10, 1997], rotary inclined drum kilns [J. Wilson, AIChE Meeting, Aug. 19-22, San Diego, CA, 1990], fluidized bed reactors [DJ Neuman, NPRA Ann. Meeting, March 19-21, San Francisco, CA, 1995, AM-95-41]. However, in all the cases described, an insufficiently complete recovery of activity was noted, associated with the formation of low-active compounds of molybdenum or nickel at the stage of regeneration, which include individual oxides MoO ₃ , NiO, nickel molybdate NiMoO ₄ or surface spinels NiAl ₂ O ₄ .

To increase the activity of the regenerated catalysts, after oxidative regeneration, they are treated with various reactivating agents, which form more active complex compounds with nickel and molybdenum.

A known method of increasing the activity of regenerated catalysts [US 7087546, B0J23 / 94, C10G45 / 04, 08.08.2006; EP 1418002, B01J23 / 85, C10G45 / 08, 12.05.2004] by impregnating them with solutions of carboxylic acids, glycols, carbohydrates containing from 1 to 3 carboxyl groups and 2-10 carbon atoms. The catalyst is impregnated with solutions of these compounds in different molar ratios and then dried at different temperatures. Compounds containing an amino group (—NH ₂ ), a hydroxo group (—OH), a carboxyl group (—COOH) can also be used as an organic additive.

Thus, the application [WO 2005070542, B0J23 / 94, B0J38 / 48, 04.08.2005] describes a method for restoring the activity of catalysts by treating them with ethylenediaminetetraacetic, nitrilotriacetic, hydroxyethylenediamine-triacetic acids. After oxidative regeneration, the catalyst is impregnated with solutions of the above additives with a molar ratio of 0.01-0.5 mol of additive per mole of active metals in the catalyst, drying the catalysts at 120 ^o C for 2 hours and subsequent calcination at 450 ^o C.

A common disadvantage for the above regenerated and reactivated catalysts is their insufficiently high activity due to the suboptimal, complex, and unidentifiable chemical composition of the catalysts obtained.

The closest in technical essence and the achieved effect to the claimed reactivated catalyst is the catalyst proposed in [RU 2484896, B01J23 / 94, C10G45 / 08, B01J37 / 02, 20.06.2013].

According to the prototype, the regenerated catalyst contains molybdenum and nickel in the form of citrate complex compounds Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], and sulfur is contained in the form of sulfate anion SO ₄ ^{2 -} in the following concentrations, wt%: Ni (C ₆ H ₆ O ₇ ) - 7.3-16.6; H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ] - 17.3-30.0; SO ₄ ² - - 0.25-2.70; the carrier is the rest, while the nickel citrates can be coordinated to the molybdenum citrate.

The main disadvantage of the prototype, as well as other known regenerated and reactivated catalysts, is their insufficiently high activity in hydrotreating. The low level of activity of the obtained catalysts is explained by their suboptimal chemical composition. To increase the activity of the catalysts, it is desirable to convert the oxygen-containing compounds contained in the regenerated catalysts (MoO ₃ , NiO, NiMoO ₄ , NiAl ₂ O ₄ ) into the form of complex compounds, which are then selectively converted into surface sulfides. Such complex compounds are citrate metal complexes, heteropolyanions with the Andersen structure, as well as phosphorus-containing heteropoly acids. In this case, it is desirable that the reactivated catalyst contains a mixture of complex compounds, which prevents the formation of large, possibly crystalline particles of any one complex compound at the stage of drying, the sulfidation of which subsequently leads to the production of coarsely dispersed low-activity catalysts. Accordingly, at the stage of reactivation, it is advisable to use solutions containing citric and phosphoric acids.

The proposed invention solves the problem of creating an improved regenerated hydrotreating catalyst, characterized by:

1. The optimal chemical composition of the catalyst containing nickel, molybdenum and phosphorus in the form of complex compounds Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ]; H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ], H ₆ [P ₂ Mo ₅ O ₂₃ ], which are then converted into the most active component of hydrotreating catalysts.

2. Optimal concentrations of complex compounds of nickel, phosphorus and molybdenum in the catalyst, wt%: Ni (C ₆ H ₆ O ₇ ) - 8.8-15.6; H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ] - 3.2-8.0; H ₇ [PNiMo ₁₁ O ₄₀ ] 5.8-11.6; H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] - 3.7-7.1; H ₆ [P ₂ Mo ₅ O ₂₃ ] - 3.0-7.4; the carrier - the rest, providing the maximum desulfurizing activity per unit weight of the catalyst.

3. The presence in the composition of the catalyst of nickel compounds, which have an increased hydrogenating and denitrogenating ability in comparison with traditional cobalt-molybdenum systems.

4. Optimal textural characteristics of catalysts, providing good access of sulfur-containing molecules of the feed to the active component, which leads to the production of petroleum products with a low sulfur content.

5. The presence of a γ-Al-based support in the catalyst composition₂O₃, additionally containing surface sulfate anions SO₄ ^2- and phosphate anions PO₄ ^3-, which in the claimed concentrations contribute to the selective production of the sulfide active component and to increase the denitrogenation activity of the catalysts.

6. Low sulfur content in the resulting diesel fuels, achieved through the use of the claimed reactivated catalysts having the claimed composition.

The problem is solved by a reactivated hydrotreating catalyst containing compounds of nickel, molybdenum, phosphorus and a carrier, while molybdenum, nickel and phosphorus are contained in the catalyst in the form of a mixture of complex compounds Ni (C₆H₆O₇), H₄[Mo₄(FROM₆H_fiveO₇)₂O_eleven], H₇ [PNiMo_elevenO₄₀]; H₃[Ni (OH)₆Mo₆O₁₈], H₆[P₂Mo_fiveO₂₃], the support contains γ-Al₂O₃, sulfur in the form of sulfate anion SO₄ ^2-, phosphorus in the form of phosphate anion PO₄ ^3-... The catalyst contains components in the following concentrations, wt%: Ni (C₆H₆O₇) - 8.8-15.6; H₄[Mo₄(FROM₆H_fiveO₇)₂O_eleven] - 3.2-8.0; H₇[PNiMo_elevenO₄₀] - 5.8-11.6; H₃[Ni (OH)₆Mo₆O₁₈] - 3.7-7.1; H₆[P₂Mo_fiveO₂₃] - 3.0-7.4; the carrier is the rest; while the support contains wt%: SO₄ ^2- - 0.5-2.5; PO₄ ^3-- 2.5-5.5; γ-Al₂O₃- the rest; after sulfidation the catalyst contains, wt%: Mo - 10.0-16.0; Ni - 2.5-4.5; P - 1.2-2.4; S 6.7-10.8; γ-Al₂O₃ - the rest.

The main distinguishing feature of the proposed reactivated catalyst in comparison with the prototype is that the catalyst contains molybdenum, nickel and phosphorus in the form of a mixture of complex compounds Ni (C₆H₆O₇), H₄[Mo₄(FROM₆H_fiveO₇)₂O_eleven], H₇ [PNiMo_elevenO₄₀]; H₃[Ni (OH)₆Mo₆O₁₈], H₆[P₂Mo_fiveO₂₃], the support contains γ-Al₂O₃, sulfur in the form of sulfate anion SO₄ ^2-, phosphorus in the form of phosphate anion PO₄ ^3-... The components are contained in the following concentrations, wt%: Ni (C₆H₆O₇) - 8.8-15.6; H₄[Mo₄(FROM₆H_fiveO₇)₂O_eleven] - 3.2-8.0; H₇[PNiMo_elevenO₄₀] - 5.8-11.6; H₃[Ni (OH)₆Mo₆O₁₈] - 3.7-7.1; H₆[P₂Mo_fiveO₂₃] - 3.0-7.4; the carrier is the rest; while the support contains wt%: SO₄ ^2- - 0.5-2.5; PO₄ ^3-- 2.5-5.5; γ-Al₂O₃- the rest; after sulfidation the catalyst contains, wt%: Mo - 10.0-16.0; Ni - 2.5-4.5; P - 1.2-2.4; S 6.7-10.8; γ-Al₂O₃ - the rest.

The catalyst has a specific surface area of 120-180 m ² / g, a pore volume of 0.30-0.55 cm ³ / g, an average pore diameter of 7-12 nm and is a particle with a cross-section in the form of a circle, trefoil or quatrefoil with a circumscribed circle diameter 1.2-1.6 mm and up to 20 mm long.

The technical effect of the proposed reactivated hydrotreating catalyst consists of the following components:

1. The claimed chemical composition of the catalyst and its texture provide maximum activity in the target reactions occurring during the hydrotreating of hydrocarbons. The presence in the composition of the catalysts of citrate and phosphate complexes of nickel and molybdenum, as well as the bimetallic heteropoly compound H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] in the claimed concentrations, selectively transforming into the most active component of the catalysts, determines the optimal surface concentration of the active component and the optimal morphology particles.

2. The presence in the composition of the catalyst carrier of sulfur in the form of surface sulphates and phosphorus in the form of surface phosphates in the claimed concentrations minimizes the undesirable interaction of active metals with the carrier surface, which leads to the formation of compounds that are inactive in catalysis.

3. The presence of nickel in the composition of the catalyst, which has an increased hydrogenating and denitrogenating ability in comparison with traditional cobalt-molybdenum systems, provides a catalyst that allows the hydrotreating of raw materials with a high content of secondary fractions.

4. The claimed textural characteristics of the obtained catalyst provide good access of the raw material molecules to be converted to the active component.

5. Carrying out hydrotreating of diesel fuel in the presence of a catalyst of the claimed chemical composition allows to obtain diesel fuel containing no more than 10 ppm sulfur at low starting temperatures of the process, which allows to extend the life of the catalyst.

Description of the proposed technical solution.

For reactivation, catalysts are used that were deactivated during their operation in the hydrotreating of diesel fuel, and then regenerated by calcining in air in belt or drum furnaces. As a rule, catalysts after oxidative regeneration have a specific surface area of 120-180 m²/ g, pore volume 0.30-0.55 cm³/ g, the average pore diameter is 7-12 nm and are particles with a cross-section in the form of a circle, trefoil or quatrefoil with a circumscribed circle diameter of 1.2-1.6 mm and a length of up to 20 mm. The catalysts contain nickel and molybdenum in terms of oxides, wt. %: NiO - 3.2-5.7; MoO₃ - 15.0-24.0; the carrier is the rest; while the support contains wt%: aluminum-bound surface sulfates SO₄ ^2- - 0.5-2.5; aluminum-bound surface phosphates PO₄ ^3-- 2.5-5.5; γ-Al₂O₃- the rest;

Next, a solution of citric and orthophosphoric acids is prepared in such concentrations that, regardless of the moisture content of the regenerated catalyst, the molar ratio of citric acid / nickel is in the range of 0.5-0.6; and the molar ratio of phosphoric acid / nickel was 0.25. For this, in a given volume of a mixture of water with 10-20 wt.% Butyldiglycol with stirring and heating, dissolve the required amount of citric and orthophosphoric acids.

Next, a sample of the calcined catalyst is impregnated with the resulting solution. The impregnation was carried out for moisture capacity, then agitation is wet catalyst in the flask of the rotary evaporator without air at a temperature of 60-90 ^{° C} for 20-60 min under conditions precluding complete evaporation of water from the catalyst.

The catalyst was dried in air at 100-220 ^C for 2-6 hours.

The presence in the catalyst of complexes of Ni, Mo, P, as well as surface sulfates and phosphates is confirmed by a combination of the following research methods: mass elemental analysis of Ni, Mo, P, C, H, S; IR spectroscopy, Raman, XPS spectroscopy.

In all cases, the mass content of elements corresponds to the concentration in the finished catalyst, wt%: Ni (C₆H₆O₇) - 8.8-15.6; H₄[Mo₄(FROM₆H_fiveO₇)₂O_eleven] - 3.2-8.0; H₇[PNiMo_elevenO₄₀] - 5.8-11.6; H₃[Ni (OH)₆Mo₆O₁₈] - 3.7-7.1; H₆[P₂Mo_fiveO₂₃] - 3.0-7.4; the carrier is the rest; while the support contains wt%: SO₄ ^2- - 0.5-2.5; PO₄ ^3-- 2.5-5.5; γ-Al₂O₃- the rest.

The IR spectra of the studied catalysts contain bands corresponding to Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [ Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ ] (table 1).

Table 1. Characteristic bands of complexes in the composition of catalysts.

Complex compound Absorption bands, cm ^-1 Ni (C ₆ H ₆ O ₇ ) 3450, 1620, 1580, 1431, 1385, 1290, 1265, 1165, 1060, 925, 890, 820 H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ] 1720, 1660, 1620, 1595, 1560, 1430, 1410; 950, 920, 900, 890, 870, 850, 820, 800, 740, 730, 690, 650, 620 H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] 945, 930, 900, 789, 633, 573, 496, 398, 322 H ₇ [PNiMo ₁₁ O ₄₀ ] 1115, 1000, 950, 897, 760, 441 H ₆ [P ₂ Mo ₅ O ₂₃ ] 1106, 1020, 988, 969, 944, 897, 861, 682

The assignments of bands in the IR spectra are made in accordance with [S.М. Tsimbler, L.L. Shevchenko, VV Grigorieva Journal of Applied Spectroscopy, 11 (1969) 522-528; R.I. Bickley, H.G.M. Edwards, R. Gustar, S. J. Rose, Journal of Molecular Structure, 246 (1991) 217-228; M. Matzapetakis, M. Dakanali, C.P. Raptopoulou, et al. Journal of Biological Inorganic Chemistry 5 (2000) 469-474; N. W. Alcock, M. Dudek, R. Grybos et al. J.Chem.Soc. Dalton Trans. (1990) 707-711; C.I. Cabello et al. Journal of Molecular Catalysis A: Chemical 186 (2002) 89-100; Feng-Xian Liu, Catherine Marchal-Roch, Damien Dambournet, Aloïs Acker, Jérome Marrot, Francis Sécheresse. Eur. J. Inorg. Chem (2008) 2191-2198].

The Raman spectra of the catalysts contain characteristic peaks H ₇ [PNiMo ₁₁ O ₄₀ ] - 974, 943, 366, 232 cm ^-1 ; H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] - 963, 946, 906, 568, 375, 353, 219 cm ^-1 ; H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ] - 945, 899, 861 389, 373, 346, 253 cm ^-1 ; H ₆ [P ₂ Mo ₅ O ₂₃ ] - 944, 900, 830, 370, 230 cm ^-1 .

The XPS spectra contain peaks corresponding to Ni (C ₆ H ₆ O ₇ ) - Ni2p3 / 2 = 856.7 eV; H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ] - Mo3d5 / 2 = 232.4 eV; H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] - Mo3d5 / 2 = 232.9 eV and Ni2p3 / 2 = 856.4 eV; H ₆ [P ₂ Mo ₅ O ₂₃ ] - Mo3d5 / 2 = 232.5 eV and P2p = 135.0 eV; SO ₄ ² - - S2p = 169.3 eV; PO ₄ ^3- - P2p = 134.2 eV.

The assignments are made in accordance with [VI Nefedov, X-ray electron spectroscopy of chemical compounds. M. Chemistry. 1984, 256 p .; L. Kaluža, R. Palcheva, A. Spojakina, K. Jirátová, G. Tyuliev. Procedia Engineering 42 (2012) 873 - 884].

The intensity of the peaks in the XPS spectra allows one to determine the concentration of each component in the catalyst.

As a result of reactivation according to the above method, catalysts are obtained having the claimed textural characteristics and containing complex compounds Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ ], as well as a γ-Al ₂ O ₃ support containing sulfur in the form of sulfate anion SO ₄ ^{2 -} , phosphorus in the form of phosphate anion PO ₄ ^{3 -} in the claimed concentration ranges.

Next, diesel fuel is hydrotreated at a volumetric feed rate in the range of 1-2.5 h ^-1 , a hydrogen / raw material ratio of 300-600 nm ³ H ₂ / m ^{3 of a} raw material, a temperature of 340-390 ° C, a hydrogen pressure of 3- 9 MPa.

The raw material used is a mixture of 87 vol.% Straight-run diesel fuel with 13 vol.% Light catalytic cracking gas oil. The raw material has a boiling range of 130-416 ° C; 90% of the volume boils away at 368 ^about C, sulfur content: 0.376 wt.%; nitrogen content 125 ppm, density 0.864 g / cm ³ .

For testing in hydrotreating catalysts are used in the form of extrudates with a cross-section in the form of a circle , trefoil or quatrefoil with a circumscribed circle diameter of 1.3-1.6 mm and an average granule length of 3-6 mm.

The preliminary sulfiding of the catalysts is carried out directly in the hydrotreating reactor with a straight-run diesel fraction containing an additional 1.5 wt.% Of a sulfiding agent, dimethyl disulfide (DMDS), at a volumetric feed rate of the sulfiding mixture of 2 h ^-1 and a hydrogen / feed ratio of 300. The sulfiding includes several stages :

- drying the catalyst in a hydrotreating reactor in a stream of hydrogen at 140 ° C for 2 h;

- wetting the catalyst with straight-run diesel fraction for 2 hours;

- supply of sulfiding mixture and temperature increase up to 240 ° C with a temperature rise rate of 25 ° C / h;

- sulfiding at a temperature of 240 ° C for 8 hours (low-temperature stage);

- increasing the reactor temperature up to 340 ° C with a temperature rise rate of 25 ° C / h;

- sulfiding at a temperature of 340 ° C for 8 hours (high-temperature stage).

After sulfiding, the catalysts contain, wt%: Mo - 10.0-16.0; Ni - 2.5-4.5; P - 1.2-2.4; S 6.7-10.8; γ-Al ₂ O ₃ - the rest.

The essence of the invention is illustrated by the following examples.

Example 1. According to the known solution.

A catalyst is used after oxidative regeneration, which contains, wt%: NiO - 4.15; MoO ₃ 16.43; SO ₄ ² - - 3.52; C - 0.11; the carrier is the rest; and has a specific surface area of 221 m ² / g, an average pore diameter of 99 nm and a pore volume of 0.54 cm ³ / g.

30 g of the catalyst after oxidative regeneration is evacuated to 50 Torr, and then contacted ^at 50 ° C for 20 min with 50 ml of citric acid solution in a mixture of ethylene glycol (50 vol.%) And ethyl alcohol (50 vol.%) Having a concentration of citric acid 2.0 mol / l, then the excess solution is decanted. The catalyst is dried 1 hour at ⁷⁰ ° C and then 4 hours at 150 ° ^C.

The resulting catalyst contains, wt%: Ni (C ₆ H ₆ O ₇ ) - 11.54; H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ] - 22.47; SO ₄ ² - 2.92; the carrier is the rest, and has a specific surface area of 215 m ² / g, an average pore diameter of 97 nm and a pore volume of 0.54 cm ³ / g.

To compare the catalytic properties, testing is carried out in the hydrotreating of the reactivated catalyst and the fresh catalyst taken from the same batch, prior to the hydrotreating and regeneration process.

The fresh catalyst used to compare the catalytic properties contains nickel and molybdenum in terms of oxides, wt%: NiO - 4.2; MoO ₃ 16.5; the carrier is the rest; and has a specific surface area of 220 m ² / g, an average pore diameter of 100 nm and a pore volume of 0.55 cm ³ / g.

The process of hydrotreating diesel fuel is carried out at a volumetric feed rate of 2.5 h ^-1 , a hydrogen / feed ratio of 600, a temperature of 370 ° C, and a hydrogen pressure of 3.8 MPa. The raw material used is a mixture of 87 vol.% Straight-run diesel fuel with 13 vol.% Light catalytic cracking gas oil. The raw material has a boiling range of 130-416 ° C; 90% of the volume boils away at 368 ^about C, the sulfur content is 0.376 wt.%; nitrogen content 125 ppm, density 0.864 g / cm ³ .

The results of diesel fuel hydrotreating on regenerated and fresh catalysts are shown in Table 2.

Examples 2-4 illustrate the proposed technical solution.

Example 2.

A catalyst is used after oxidative regeneration, which contains, wt%: NiO - 3.15; MoO₃ - 15.0; SO₄ ^2- - 2.5; PO₄ ^3-- 2.5; γ-Al support₂O₃ - the rest; and has a specific surface area of 180 m²/ g, average pore diameter 7 nm, pore volume 0.55 cm³/ g, moisture content 0.6 cm³/ g.

Next, a solution of citric and orthophosphoric acids is prepared in such concentrations that, regardless of the moisture content of the regenerated catalyst, the molar ratio of citric acid / nickel is in the range of 0.5-0.6; and the molar ratio of phosphoric acid / nickel was 0.25. For this, in a given volume of a mixture of water with 10-20 wt.% Butyldiglycol with stirring and heating, dissolve the required amount of citric and orthophosphoric acids.

A solution of 12 ml of butyldiglycol in 40 ml of water is prepared. Next, a weighed portion of citric acid of 4.84 g (0.025 mol) and 1.22 g of an 85% aqueous solution of orthophosphoric acid (0.01 mol) are dissolved in the resulting solution. The volume of the solution is adjusted to 60 ml with distilled water. A portion of 100 g of the catalyst after oxidative regeneration in a flask eliminating evaporation of water, was impregnated to 60 ml of solution of citric and phosphoric acid in a mixture of water and butyldiglycol, the flask was fixed to a rotary device and placed in a bath heated to ⁶⁰ ° C, with constant rotation, providing mixing catalyst, incubated for 20 minutes. The catalyst was then transferred to a Petri dish which was placed in an oven heated ^to 100 ° C, and dried at this temperature for 2 h. Before determining the textural characteristics of the catalyst is heated in air for 2 hours at 500 ° ^C.

The resulting catalyst contains, wt%: Ni (C₆H₆O₇) - 8.8; H₄[Mo₄(FROM₆H_fiveO₇)₂O_eleven] - 7.1; H₇[PNiMo_elevenO₄₀] - 5.8; H₃[Ni (OH)₆Mo₆O₁₈] - 3.7; H₆[P₂Mo_fiveO₂₃] - 3.0; the carrier is the rest; while the support contains wt%: SO₄ ^2- - 2.5; PO₄ ^3-- 2.5; γ-Al₂O₃- the rest. The catalyst has a specific surface area of 180 m²/ g, pore volume 0.55 cm³/ g, the average pore diameter is 7 nm and is a particle with a trefoil section with a circumscribed circle diameter of 1.2 mm and a length of up to 20 mm.

The IR spectra of the catalyst contain all characteristic bands typical of Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ ], shown in Table 1. Raman spectra also contain a set of peaks from Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ ]. The binding energies and peak intensities determined from the XPS spectra correspond to the presence of Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ , also a γ-Al ₂ O ₃ carrier containing sulfur in the form of sulfate anion SO ₄ ^2- , phosphorus in the form of phosphate anion PO ₄ ^3- in the claimed concentration ranges.

Hydrotreating diesel fuel and preliminary sulfiding are carried out analogously to example 1. After sulfiding, the catalyst contains, wt%: Mo - 10.0; Ni - 2.5; P - 1.2; S 6.7; γ-Al ₂ O ₃ - the rest.

To compare the catalytic properties, testing is carried out in the hydrotreating of the reactivated catalyst and the fresh catalyst taken from the same batch, prior to the hydrotreating and regeneration process.

The results of diesel fuel hydrotreating on a regenerated catalyst are shown in Table 2.

Example 3.

A catalyst is used after oxidative regeneration, which contains, wt%: NiO - 6.7; MoO₃ - 24.0; SO₄ ^2- - 0.5; PO₄ ^3-- 5.5; γ-Al support₂O₃ - the rest; and has a specific surface area of 120 m²/ g, average pore diameter 12 nm and pore volume 0.30 cm³/ g, moisture content 0.35 cm³/ g.

Prepare a solution of 5.5 ml of butyldiglycol in 15 ml of water. Next, a weighed portion of citric acid of 7.32 g (0.038 mol) and 2.2 g of an 85% aqueous solution of phosphoric acid (0.019 mol) are dissolved in the resulting solution. The volume of the solution is adjusted to 35 ml with distilled water. A portion of 100 g of the catalyst after oxidative regeneration in a flask eliminating evaporation of water, was impregnated 35 ml of a solution of citric and phosphoric acid in a mixture of water and butyldiglycol, the flask was fixed to a rotary device and placed in a bath heated to 90 ^{° C,} with constant rotation, providing mixing catalyst, incubated for 60 minutes. The catalyst was then transferred to a Petri dish which was placed in an oven heated to 220 ^{° C} and dried at the temperature for 6 hours. Before determining the textural characteristics of the catalyst is heated in air for 2 hours at 500 ° ^C.

The resulting catalyst contains, wt%: Ni (C₆H₆O₇) - 15.6; H₄[Mo₄(FROM₆H_fiveO₇)₂O_eleven] - 3.2; H₇[PNiMo_elevenO₄₀] - 11.6; H₃[Ni (OH)₆Mo₆O₁₈] - 7.1; H₆[P₂Mo_fiveO₂₃] - 7.4; the carrier is the rest; while the support contains wt%: SO₄ ^2- - 0.5; PO₄ ^3-- 5.5; γ-Al₂O₃- the rest. The catalyst has a specific surface area of 120 m²/ g, pore volume 0.3 cm³/ g, the average pore diameter is 12 nm and is a four-leafed particle with a circumscribed circle diameter of 1.6 mm and a length of up to 20 mm.

The IR spectra of the catalyst contain all characteristic bands typical of Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ ] are shown in Table 1. Raman spectra also contain a set of peaks from Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ ]. The binding energies and peak intensities determined from the XPS spectra correspond to the presence of Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ , also a γ-Al ₂ O ₃ carrier containing sulfur in the form of sulfate anion SO ₄ ^2- , phosphorus in the form of phosphate anion PO ₄ ^3- in the claimed concentration ranges.

Hydrotreating diesel fuel and preliminary sulfiding are carried out analogously to example 1. After sulfiding, the catalyst contains, wt%: Mo - 16.0; Ni 4.5; P - 2.4; S 10.8; γ-Al ₂ O ₃ - the rest.

To compare the catalytic properties, testing is carried out in the hydrotreating of the reactivated catalyst and the fresh catalyst taken from the same batch, prior to the hydrotreating and regeneration process.

The results of diesel fuel hydrotreating on a regenerated catalyst are shown in Table 2.

Example 4.

A catalyst is used after oxidative regeneration, which contains, wt%: NiO - 4.5; MoO₃ - 19.5; SO₄ ^2- - 1.8; PO₄ ^3-- 4.5; γ-Al support₂O₃ - the rest; and has a specific surface area of 150 m²/ g, average pore diameter 9 nm, pore volume 0.45 cm³/ g, moisture content 0.5 cm³/ g.

A solution of 10 ml of butyldiglycol in 25 ml of water is prepared. Next, a weighed portion of citric acid of 6.83 g (0.036 mol) and 1.73 g of an 85% aqueous solution of phosphoric acid (0.015 mol) are dissolved in the resulting solution. The volume of the solution is adjusted to 50 ml with distilled water. A portion of 100 g of the catalyst after oxidative regeneration in a flask eliminating evaporation of water, was impregnated with 50 ml of solution of citric and phosphoric acid in a mixture of water and butyldiglycol, the flask was fixed to a rotary device and placed in a bath heated to 75 ^{° C,} with constant rotation, providing mixing catalyst, stand for 40 minutes. The catalyst was then transferred to a Petri dish which was placed in an oven heated to ¹²⁰ ° C, and dried at this temperature for 4 hours. Before determining the textural characteristics of the catalyst is heated in air for 2 hours at 500 ° ^C.

The resulting catalyst contains, wt%: Ni (C ₆ H ₆ O ₇ ) - 12.5; H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ] - 8.0; H ₇ [PNiMo ₁₁ O ₄₀ ] 7.3; H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] - 5.0; H ₆ [P ₂ Mo ₅ O ₂₃ ] - 5.0; the carrier is the rest; the support contains wt%: SO ₄ ² - 1.8; PO ₄ ³ - 4.5; γ-Al ₂ O ₃ - the rest. The catalyst has a specific surface area of 150 m ² / g, a pore volume of 0.45 cm ³ / g, an average pore diameter of 9 nm and is a particle with a circular cross-section with a diameter of 1.4 mm and a length of up to 20 mm.

The IR spectra of the catalyst contain all characteristic bands typical of Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ ], shown in Table 1. Raman spectra also contain a set of peaks from Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ ]. The binding energies and peak intensities determined from the XPS spectra correspond to the presence of Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ], H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] and H ₆ [P ₂ Mo ₅ O ₂₃ , also a γ-Al ₂ O ₃ carrier containing sulfur in the form of sulfate anion SO ₄ ^2- , phosphorus in the form of phosphate anion PO ₄ ^3- in the claimed concentration ranges.

Hydrotreating diesel fuel and preliminary sulfiding are carried out analogously to example 1. After sulfiding, the catalyst contains, wt%: Mo - 13.0; Ni - 3.5; P - 2.1; S 9.9; γ-Al ₂ O ₃ - the rest.

To compare the catalytic properties, testing is carried out in the hydrotreating of the reactivated catalyst and the fresh catalyst taken from the same batch, prior to the hydrotreating and regeneration process.

The results of diesel fuel hydrotreating on a regenerated catalyst are shown in Table 2.

Table 2. Results of diesel fuel hydrotreating on regenerated and fresh catalysts.

Catalyst Residual sulfur content in diesel fuel, ppm Desulfurization degree,% Recovery of activity,% Example 1, regenerated 36.0 99.04 99,80 Example 1 fresh 30.0 99.20 --- Example 2 regenerated 20.3 99.46 99.98 Example 2 fresh 19.6 99.48 --- Example 3 regenerated 14.8 99.61 100.0 Example 3 fresh 14.5 99.61 --- Example 4 regenerated 9.5 99.75 100.02 Example 4 fresh 10.0 99.73 ---

From the results of diesel fuel hydrotreating, shown in Table 2, it follows that the claimed reactivated catalysts under the hydrotreating conditions used provide a degree of desulfurization of mixed diesel fuel of at least 99.46%, have an activity in the range of 99.98-100.02% of the activity of fresh catalysts ...

Claims (1)

The reactivated hydrotreating catalyst containing, wt%: Mo - 10.0-16.0; Ni - 2.5-4.5; P - 1.2-2.4; S 6.7-10.8; γ-Al ₂ O ₃ - the rest obtained by sulfiding a mixture containing complex compounds Ni (C ₆ H ₆ O ₇ ), H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ], H ₇ [PNiMo ₁₁ O ₄₀ ]; H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ], H ₆ [P ₂ Mo ₅ O ₂₃ ] and a support containing γ-Al ₂ O ₃ , sulfur in the form of sulfate anion SO ₄ ^2- , phosphorus in the form of phosphate -anion PO ₄ ^3- , in the following concentrations, wt.%: Ni (C ₆ H ₆ O ₇ ) - 8.8-15.6; H ₄ [Mo ₄ (C ₆ H ₅ O ₇ ) ₂ O ₁₁ ] - 3.2-8.0; H ₇ [PNiMo ₁₁ O ₄₀ ] 5.8-11.6; H ₃ [Ni (OH) ₆ Mo ₆ O ₁₈ ] - 3.7-7.1; H ₆ [P ₂ Mo ₅ O ₂₃ ] - 3.0-7.4; the carrier is the rest; while the carrier contains wt.%: SO ₄ ² - - 0.5-2.5; PO ₄ ³ - 2.5-5.5; γ-Al ₂ O ₃ - the rest.