Hydrotreating method of chlorine-containing biological oil

Abstract

The invention relates to the field of treatment of biological oil and fat, and discloses a hydrotreating method of chlorine-containing biological oil and fat. The method comprises the following steps: (1) carrying out a dechlorination reaction on chlorine-containing biological oil and hydrogen under the action of a hydrodechlorination catalyst to obtain a material flow W; (2) carrying out deoxidation reaction on the material flow W under the action of a hydrodeoxygenation catalyst; wherein the hydrodechlorination catalyst comprises a modified carrier and an active metal component loaded on the modified carrier, and the modified carrier comprises a carrier and alkaline earth metal; the active metal component comprises a group VIB metal component and a group VIII metal component; on the basis of the total weight of the modified carrier, the content of alkaline earth metal is 20-50 wt% in terms of oxide, and the breakthrough chlorine capacity of the hydrodechlorination catalyst is not lower than 20%. According to the method, chlorine in the biological oil and fat can be efficiently removed, and the problem that chlorine ions corrode a device in the biological oil and fat processing process is effectively solved.

Description

Technical Field

[0001] The invention relates to the field of biological oil treatment, and in particular to a hydrogenation treatment method for chlorine-containing biological oil. Background Art

[0002] At present, the petroleum and petrochemical industry, as the main source of carbon emissions, faces increasingly severe challenges and tests, and energy transformation is imminent. Biomass raw materials are renewable, abundant and carbon neutral, which can provide a diversified clean energy supply for transportation and greatly reduce carbon emissions. As a major biomass raw material, bio-oils and fats have high value conversion that meets the requirements of the circular economy and is conducive to maintaining energy security. Their strategic significance and social value are higher than their economic benefits, so their application has received widespread attention.

[0003] Biodiesel can be directly produced by using bio-oil as raw material through the hydrorefining process. The preparation process is green and low-carbon, and it is the main way to convert bio-oil into high value. There are also many problems in the high-value conversion of waste cooking oil. One of the problems is that the chlorine and oxygen content in waste cooking oil is relatively high, and hydrogen chloride and water are easily generated during the hydrorefining process. Hydrogen chloride and water will generate highly concentrated hydrochloric acid under liquid phase conditions, especially under the dew point conditions of water, which will not only cause serious corrosion to the reactor, heat exchanger and corresponding pipelines, but also form ammonium chloride salts to block the equipment pipelines. These problems pose serious safety hazards to the safe and stable operation of the device. Therefore, the removal of chlorine in waste cooking oil has become a key technical problem.

[0004] At present, the methods for removing organic chlorine reported in the literature mainly include adsorption dechlorination, nucleophilic substitution reaction dechlorination, metal reduction dechlorination and catalytic hydrogenation dechlorination. Among them, adsorption dechlorination is mainly aimed at the removal of HCl produced after the conversion of organic chlorine, using physical adsorbents (molecular sieves / activated carbon) and chemical adsorbents (alkaline earth metal oxides) as adsorption media, and has good removal effect on HCl in the gas phase and high chlorine capacity, but poor removal effect on HCl in the liquid phase and low chlorine capacity; nucleophilic substitution dechlorination method mainly uses nucleophilic substitution reagents (alcohol solution / ammonia solution / alkaline solution) to achieve organic chlorine removal, but has the disadvantages of long reaction time and high cost; metal reduction dechlorination method uses nano-scale Pd / Fe as catalyst to remove organic chlorine through reduction reaction, which is characterized by large catalyst specific surface area and high reaction rate, but the disadvantage is that the catalyst cost and energy consumption are high; catalytic hydrogenation dechlorination method uses hydrogenation dechlorination catalyst to remove organic chlorine, focusing on converting organic chlorine into inorganic chlorine (HCl), and does not consider the removal of HCl.

[0005] CN104560413 B and CN110628511A respectively disclose a method for treating waste restaurant oil by hydrogenation and dechlorination and hydrogenation and preparing liquid paraffin by dechlorination and hydrogenation of waste animal and plant oils, which mainly use a dechlorination adsorbent in a post-dechlorination reactor to adsorb the hydrogen chloride generated in the refining process, but the use of a high-pressure dechlorination reactor generates additional equipment investment, and at the same time, part of the hydrogen chloride generated in the refining process is dissolved in the liquid phase oil product at high temperature, resulting in a low penetration capacity of the dechlorination adsorbent. In order to avoid the corrosion of the hydrogen chloride generated in the reaction process to the device, a large amount of dechlorination adsorbent needs to be loaded to fully adsorb the hydrogen chloride. Therefore, the increase in equipment investment and the large-scale use of dechlorination adsorbents seriously affect the high-value conversion of bio-oils, and it is crucial to develop a low-cost and efficient bio-oil hydrogenation treatment method. Summary of the invention

[0006] The purpose of the present invention is to overcome the problems of poor removal of chlorine in bio-grease in the prior art, which causes pipeline blockage, device corrosion and other problems, and to provide a method for hydrogenation treatment of chlorine-containing bio-grease. The method can efficiently remove chlorine from bio-grease and effectively solve the problem of corrosion of chloride ions on the device during the processing of bio-grease.

[0007] In order to achieve the above object, the present invention provides a method for hydrogenating chlorine-containing biological oils and fats, the method comprising:

[0008] (1) dechlorinating the bio-oil with hydrogen under the action of a hydrodechlorination catalyst to obtain a stream W;

[0009] (2) subjecting the stream W to a deoxygenation reaction under the action of a hydrodeoxygenation catalyst;

[0010] The hydrodechlorination catalyst comprises a modified carrier and an active metal component supported on the modified carrier, wherein the modified carrier comprises a carrier and an alkaline earth metal; the active metal component comprises a metal component of Group VIB and a metal component of Group VIII; the content of the alkaline earth metal is 20-50% by weight, calculated as oxide, based on the total weight of the modified carrier;

[0011] Wherein, the breakthrough chlorine capacity of the hydrodechlorination catalyst is not less than 20%.

[0012] Through the above technical solution, the beneficial effects of the present invention include:

[0013] In the hydroprocessing method of the present invention, two catalysts, namely, a specific type of hydrodechlorination catalyst and a hydrodeoxygenation catalyst, are rationally graded, which can give full play to the respective advantages of the two catalysts, convert the organic chlorine in the bio-oil into hydrogen chloride (dechlorination) and adsorb the hydrogen chloride in situ on the hydrodechlorination catalyst, thereby realizing gas phase adsorption of hydrogen chloride, efficiently removing the chlorine in the bio-oil, and effectively solving the problem of corrosion of the equipment by chloride ions during the processing of the bio-oil; at the same time, the oxygen-containing compounds in the raw materials can be refined and removed to produce high-quality refined oil products.

[0014] The hydroprocessing method provided by the invention has the advantages of simple operation, mild conditions and low cost. DETAILED DESCRIPTION

[0015] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0016] The first aspect of the present invention provides a method for hydrogenating chlorine-containing biological oils and fats, the method comprising:

[0017] (1) dechlorinating the bio-oil with hydrogen under the action of a hydrodechlorination catalyst to obtain a stream W;

[0018] (2) subjecting the stream W to a deoxygenation reaction under the action of a hydrodeoxygenation catalyst;

[0019] The hydrodechlorination catalyst comprises a modified carrier and an active metal component supported on the modified carrier, wherein the modified carrier comprises a carrier and an alkaline earth metal; the active metal component comprises a metal component of Group VIB and a metal component of Group VIII; the content of the alkaline earth metal is 20-50% by weight, calculated as oxide, based on the total weight of the modified carrier;

[0020] Wherein, the breakthrough chlorine capacity of the hydrodechlorination catalyst is not less than 20%.

[0021] In the prior art, the method of pre-deoxygenation and post-dechlorination is usually used to treat chlorine-containing bio-oil. In this process, the dechlorination adsorbent in the post-dechlorination reactor adsorbs the hydrogen chloride generated in the refining process. However, the use of the high-pressure dechlorination reactor generates additional equipment investment. At the same time, part of the hydrogen chloride generated in the refining process is dissolved in the liquid phase oil at high temperature, which is difficult to be absorbed. A large amount of dechlorination adsorbent needs to be loaded to fully adsorb the hydrogen chloride. The method provided by the present invention overcomes the above-mentioned defects, and uses a hydrodechlorination catalyst and a hydrodeoxygenation catalyst for reasonable grading. First, the organic chlorine in the bio-oil is converted into hydrogen chloride and the hydrogen chloride can be adsorbed in situ on the hydrodechlorination catalyst to achieve gas phase adsorption of hydrogen chloride, and the chlorine in the bio-oil is efficiently removed; then the oxygen-containing compounds in the raw material are refined and removed to produce high-quality refined oil products.

[0022] The hydrodechlorination catalyst of the present invention has a high breakthrough chlorine capacity and exhibits good chlorine adsorption activity. In the present invention, the breakthrough chlorine capacity of the hydrodechlorination catalyst is not less than 20%, preferably 20-32%.

[0023] The penetration chlorine capacity of the catalyst of the present invention is measured by the chlorine capacity test method of alkaline earth metal high temperature dechlorination agent (GB / T38108-2019).

[0024] In the present invention, based on the total weight of the modified support, the content of the alkaline earth metal in terms of oxide is 20-50% by weight, preferably 20-40% by weight, more preferably 25-35% by weight, for example, it can be 20% by weight, 25% by weight, 30% by weight, 35% by weight, 40% by weight, 45% by weight, 50% by weight, and any value in the range formed by any two of these values. The inventors of the present invention have found that in this preferred case, it is beneficial to improve the chlorine adsorption activity of the catalyst.

[0025] The content of alkaline earth metal in the catalyst of the present invention is measured by X-ray fluorescence spectrometry (XRF).

[0026] Preferably, the alkaline earth metal element is selected from at least one of magnesium, calcium, strontium and barium, preferably magnesium and / or calcium, more preferably magnesium. In this preferred embodiment, the catalyst has a higher structural stability.

[0027] The modified carrier of the present invention has a large specific surface area and a suitable pore volume, suitable interaction force with the active metal component, and high structural stability, so that the catalyst of the present invention has good dechlorination activity and chlorine adsorption activity, as well as high dechlorination stability.

[0028] According to the present invention, preferably, the specific surface area of ​​the modified carrier is 150-250m 2 / g, preferably 180-220m 2 / g.

[0029] According to the present invention, preferably, the pore volume of the modified carrier is 0.5-0.7 cm 3 / g, preferably 0.55-0.65cm 3 / g.

[0030] The specific surface area and pore volume of the modified carrier of the present invention are measured by BET physical adsorption-desorption analysis method.

[0031] According to the present invention, preferably, the modified carrier does not have a spinel structure. In this preferred embodiment, the catalyst is conducive to fully adsorbing hydrogen chloride generated by the dechlorination reaction, and further conducive to improving the chlorine adsorption activity of the catalyst.

[0032] It should be noted that when the modified carrier has a spinel structure, it will be unfavorable for the catalyst to adsorb hydrogen chloride and affect the catalyst's chlorine adsorption activity.

[0033] The carrier of the present invention can be a conventional choice in the art. Preferably, the carrier is a heat-resistant inorganic oxide, preferably at least one selected from silicon oxide, aluminum oxide, zirconium oxide and titanium oxide, more preferably aluminum oxide. By adopting this preferred embodiment, the modified carrier has a higher specific surface area and pore volume, and also has a higher crushing strength.

[0034] The hydrodechlorination catalyst of the present invention adopts a specific type of bimetallic active component, which is more conducive to improving the dechlorination activity compared with the monometallic active component. In order to make the hydrodechlorination catalyst show better dechlorination activity in the hydrogenation reaction, preferably, based on the total weight of the hydrodechlorination catalyst, the content of the VIB group metal component is 5-20wt%, preferably 5-15wt%, more preferably 10-15wt% in terms of oxide; the content of the VIII group metal component is 0.5-10wt%, preferably 0.8-5wt%, more preferably 1-3wt%.

[0035] In the catalyst of the present invention, the sum of the contents of the various components is 100%.

[0036] The content of active metal components in the catalyst of the present invention is measured by X-ray fluorescence spectrometry (XRF).

[0037] The VIB group metal component of the present invention can be a conventional choice in the art. Preferably, the VIB group metal component is selected from at least one of chromium, molybdenum and tungsten, preferably molybdenum and / or tungsten.

[0038] The Group VIII metal component of the present invention can be a conventional choice in the art. Preferably, the Group VIII metal component is nickel and / or cobalt.

[0039] According to the present invention, preferably, the method for preparing the hydrodechlorination catalyst comprises the following steps:

[0040] (a) mixing a carrier precursor and an alkaline earth metal precursor to form a mixture, and then optionally drying and calcining the mixture to obtain a modified carrier;

[0041] (b) introducing active metal components onto the modified support obtained in step (a) by impregnation.

[0042] The present invention has a wide range of choices for the alkaline earth metal precursor, which can be any conventional choice in the art, as long as it contains alkaline earth metal. Preferably, the alkaline earth metal precursor is an alkaline earth metal oxide and / or an alkaline earth metal acid salt.

[0043] According to the present invention, preferably, the alkaline earth metal acid salt is selected from at least one of alkaline earth metal carbonates, alkaline earth metal nitrates, alkaline earth metal phosphates and alkaline earth metal sulfates, preferably alkaline earth metal carbonates, more preferably alkaline earth metal basic carbonates.

[0044] The type of carrier precursor of the present invention is a conventional choice in the art. Preferably, the carrier precursor is selected from at least one of pseudo-boehmite, boehmite, aluminum sol, acidified aluminum sol, amorphous hydrated aluminum oxide, aluminum trihydrate, boehmite, silica sol, phosphate aluminum colloid, silica aluminum sol, zircon sol and titanium sol, preferably selected from at least one of pseudo-boehmite, boehmite, aluminum sol, amorphous hydrated aluminum oxide, aluminum trihydrate and boehmite.

[0045] Preferably, the mixing in step (a) is carried out under stirring conditions.

[0046] The present invention has no particular limitation on the specific stirring conditions, which can be appropriately selected according to the specific circumstances, as long as the purpose of uniform mixing can be achieved.

[0047] In the present invention, the stirring may be performed in a container with a stirring device or in a beater.

[0048] In the mixing process of step (a), water may be added or not. Generally, from the perspective of improving the uniformity of mixing, it is preferred to add water during the mixing process. The present invention does not specifically limit the amount of water to ensure smooth subsequent molding. Preferably, the weight ratio of water to alkaline earth metal precursor is 3-15:1.

[0049] During the mixing process of step (a), a peptizing agent and an extrusion aid may or may not be added.

[0050] The present invention has no particular limitation on the type and amount of the peptizer and the extrusion aid, which can be selected conventionally in the art to ensure smooth molding.

[0051] The present invention does not particularly limit the molding method of step (a), and the molding method commonly used in the art can be adopted. Preferably, the molding of step (a) is extrusion molding, spray molding, spheronization molding or tableting molding, preferably extrusion molding.

[0052] The present invention also has no particular limitation on the shape of the molded product obtained by molding in step (a), which may be one or more of spherical, honeycomb, bird's nest, sheet, and strip (such as clover, disc, cylinder, and Raschig ring).

[0053] The drying and calcining in step (a) can be carried out by conventional methods in the art.

[0054] The drying in step (a) can be oven drying or vacuum drying. Preferably, the drying conditions in step (a) include: a temperature of 60-280°C, preferably 80-250°C, more preferably 110-200°C; a time of 1-48 hours, preferably 2-24 hours, more preferably 2-12 hours.

[0055] According to the present invention, preferably, the calcination conditions in step (a) include: a temperature of 300-600°C, preferably 350-550°C; a time of 1-10 hours, preferably 2-8 hours. The calcination is generally carried out in an air atmosphere, which may include a flowing atmosphere or a static atmosphere. This preferred embodiment is conducive to obtaining a modified carrier without a spinel structure.

[0056] The present invention has no particular limitation on the order of introducing the Group VIB metal component and the Group VIII metal component in step (b); they may be introduced together or separately.

[0057] In the preparation method provided by the present invention, the impregnation method in step (b) can be a saturated impregnation method or a supersaturated impregnation method. There is no particular limitation on the environment of the impregnation method, and the impregnation method can be carried out in a sealed condition or in an open environment according to conventional methods in the art.

[0058] Preferably, step (b) comprises: impregnating the modified support in an impregnation solution containing an active metal component compound, followed by drying and calcining.

[0059] The present invention does not particularly limit the conditions for the impregnation, and the specific impregnation method is a conventional choice in the art. For example, the conditions for the impregnation include an impregnation temperature of 20-300° C. and an impregnation time of 1-20 hours.

[0060] The drying and calcining in step (b) can be carried out by conventional methods in the art, and the conditions can be the same as those of the drying and calcining in step (a).

[0061] In the present invention, the hydrodeoxygenation catalyst may be any of various hydrodeoxygenation catalysts commonly used in the art. Preferably, the hydrodeoxygenation catalyst comprises alumina and a Group VIB metal component and a Group VIII metal component supported on the alumina.

[0062] According to the present invention, preferably, based on the total weight of the hydrodeoxygenation catalyst, the content of the VIB group metal component is 5-30 wt%, and the content of the VIII group metal component is 1-10 wt%, calculated as oxide.

[0063] It is understood that in the hydrodeoxygenation catalyst, the balance is the content of alumina.

[0064] The VIB group metal component of the present invention can be a conventional choice in the art. Preferably, in the hydrodeoxygenation catalyst, the VIB group metal component is molybdenum and / or tungsten.

[0065] The Group VIII metal component of the present invention can be a conventional choice in the art. Preferably, in the hydrodeoxygenation catalyst, the Group VIII metal component is nickel and / or cobalt.

[0066] The present invention has no particular limitation on the source of the hydrodeoxygenation catalyst, which can be obtained commercially or prepared by conventional methods in the art.

[0067] In the present invention, the hydrodechlorination catalyst and the hydrodeoxygenation catalyst can be respectively loaded in two reactors connected in series, or loaded in different beds of one reactor. In order to reduce equipment investment and save costs, preferably, the hydrodechlorination catalyst and the hydrodeoxygenation catalyst are loaded in different beds of one reactor, and along the logistics direction, the hydrodechlorination catalyst is located upstream of the hydrodeoxygenation catalyst.

[0068] The present invention has no particular limitation on the loading ratio of the hydrodechlorination catalyst to the hydrodeoxygenation catalyst, and can be appropriately adjusted according to the composition of the bio-oil (mainly referring to the organic chlorine content and oxygen content). Preferably, the loading volume ratio of the hydrodechlorination catalyst to the hydrodeoxygenation catalyst is 1:1-20.

[0069] According to the present invention, preferably, the conditions of the dechlorination reaction in step (1) include: a temperature of 200-350°C, preferably 250-300°C; a pressure of 3-15MPa, preferably 5-8MPa; a liquid hourly volume space velocity of 0.1-10h -1 , preferably 0.5-2h -1 ; The volume ratio of hydrogen to oil is 300-3000, preferably 800-1200.

[0070] According to the present invention, preferably, the conditions of the deoxygenation reaction in step (2) include: a temperature of 200-400°C, preferably 280-350°C; a pressure of 3-15MPa, preferably 5-8MPa; a liquid hourly volume space velocity of 0.1-10h -1 , preferably 0.5-2h -1 ; The volume ratio of hydrogen to oil is 300-3000, preferably 800-1200.

[0071] Preferably, the treatment method further comprises: performing gas-liquid separation on the hydrodeoxygenation reaction product to obtain a hydrorefined oil product.

[0072] The present invention has no particular limitation on the gas-liquid separation method, and the gas-liquid separation can be performed according to conventional methods in the art.

[0073] The catalyst of the present invention can be applied to the treatment of biological oils and fats with different organic chlorine and oxygen concentrations.

[0074] Preferably, the content of organic chlorine in the biological oil is not less than 10 mg / kg, preferably 50-100 mg / kg.

[0075] Preferably, in the bio-grease, the oxygen content is not higher than 15 wt %.

[0076] Preferably, the organic chlorine comes from chlorine-containing organic matter in biological oils and fats, and the chlorine-containing organic matter includes at least one of chlorinated alkanes, chlorinated olefins and chlorinated aromatics.

[0077] The biological oil of the present invention may also contain sulfur, and mechanical impurities such as iron, nickel, vanadium, sodium and calcium.

[0078] Preferably, the total content of mechanical impurities in the biological oil is not higher than 0.1 wt %.

[0079] Preferably, the sulfur content in the bio-oil is not higher than 30 mg / kg.

[0080] The present invention has a wide range of choices for the types of bio-fat to be processed, which can be plant fat or animal fat, for example, one or more of restaurant waste oil (such as swill oil), palmitic acid oil, coconut oil, palm oil, etc.

[0081] Preferably, the hydrodechlorination catalyst and the hydrodeoxygenation catalyst are sulfided before use.

[0082] The present invention has no particular limitation on the specific conditions of the vulcanization, and the vulcanization can be carried out according to conventional methods in the art.

[0083] The present invention will be described in detail below through examples.

[0084] In the following examples, the organic chlorine content parameter is measured by X-ray fluorescence spectroscopy; the inorganic chlorine content is measured by ion chromatography analysis.

[0085] Preparation Example 1

[0086] (1) Preparation of modified carrier: 1 kg of pseudo-boehmite dry rubber powder (70 wt% Al2O3) and 300 g of magnesium oxide and 30 g of sesbania powder were mixed evenly, and then 1200 ml of water and 20 mL of nitric acid were added. The mixture was kneaded and extruded on a twin-screw extruder to obtain butterfly-shaped strips of Φ1.3 mm. The strips were then dried at 120°C for 3 hours and calcined at 500°C in air atmosphere for 3 hours to obtain modified carrier A1.

[0087] (2) Preparation of hydrodechlorination catalyst: Molybdenum oxide and basic cobalt carbonate were dispersed in water to form an impregnation solution. The impregnation solution was used to saturate the A1 modified carrier at 25°C for 1 hour, then dried at 120°C for 2 hours, and calcined at 400°C in an air atmosphere for 3 hours to obtain a hydrodechlorination catalyst C1. The composition and performance parameters of the catalyst are shown in Table 1.

[0088] Preparation Example 2

[0089] (1) Preparation of modified carrier: 1 kg of pseudo-boehmite dry rubber powder (70 wt% Al2O3) and 377 g of calcium oxide and 30 g of sesbania powder were mixed evenly, and then 1200 ml of water and 20 mL of nitric acid were added. The mixture was then kneaded and extruded on a twin-screw extruder to obtain butterfly-shaped strips of Φ1.3 mm. The strips were then dried at 120°C for 3 hours and calcined at 500°C in air atmosphere for 3 hours to obtain modified carrier A2.

[0090] (2) Preparation of hydrodechlorination catalyst: Molybdenum oxide and basic nickel carbonate were dispersed in water to form an impregnation solution. The impregnation solution was used to saturate the A2 modified carrier at 25°C for 1 hour, then dried at 120°C for 2 hours, and calcined at 400°C in an air atmosphere for 3 hours to obtain a hydrodechlorination catalyst C2. The composition and performance parameters of the catalyst are shown in Table 1.

[0091] Preparation Example 3

[0092] The method of Preparation Example 1 was followed, except that the amount of magnesium oxide was changed so that the content of alkaline earth metal calculated as oxide was 22 wt % based on the total weight of the modified support.

[0093] The hydrodechlorination catalyst C3 was obtained, and its composition and performance parameters are shown in Table 1.

[0094] Comparative Preparation Example 1

[0095] The method of Example 1 is followed, except that step (1) is not performed. Instead, the pseudo-boehmite dry rubber powder is first extruded into strips, dried at 120°C for 3 hours, and calcined at 500°C in an air atmosphere for 3 hours to obtain an alumina carrier; an aqueous solution of magnesium nitrate (1 g / mL) is impregnated on the modified alumina carrier, dried at 120°C for 3 hours, and calcined at 500°C in an air atmosphere for 3 hours, and then the above impregnation-drying-calcination operation is repeated twice to obtain a modified carrier S1.

[0096] The hydrodechlorination catalyst D1 was obtained, and its composition and performance parameters are shown in Table 1.

[0097] Table 1

[0098]

[0099] Example 1

[0100] The total loading volume of the catalyst in the fixed bed hydrogenation reactor is 100 mL. Along the logistics direction, the fixed bed hydrogenation reactor is sequentially loaded with the hydrodechlorination catalyst prepared in Preparation Example 1 and the RJW-3 hydrodeoxygenation catalyst (produced by Changling Catalyst Factory), and the volume contents of the two are 30% and 70%, respectively. The hydrodechlorination catalyst and the hydrodeoxygenation catalyst are subjected to programmed temperature sulfurization: straight-run kerosene containing 2% dimethyl disulfide by mass is used as the sulfurized oil, and the temperature is increased from 110°C to 230°C at a rate of 20°C / h, and maintained for 6h; then the temperature is increased to 360°C at a rate of 20°C / h, and maintained for 6h. After the hydrogen and the bio-oil raw material (composition is shown in Table 2) are mixed, they enter the hydrogenation reactor and contact with the hydrodechlorination catalyst and the hydrodeoxygenation catalyst in turn for hydrogenation reaction. The reaction product is separated by gas and liquid to obtain a hydrorefined oil product and reaction water. The operating conditions of the hydrogenation reactor are: pressure 6.4MPa, bio-oil flow rate of 100mL / h, hydrogen flow rate of 100L / h, average temperature of the hydrodechlorination reaction bed of 260℃, and average temperature of the hydrodeoxygenation reaction bed of 320℃.

[0101] The organic chlorine content, oxygen content in the hydrorefined oil after different reaction times and the inorganic chlorine content in the separated water were analyzed. The results are shown in Table 3.

[0102] Example 2

[0103] The total loading volume of the catalyst in the fixed bed hydrogenation reactor is 100 mL. Along the logistics direction, the fixed bed hydrogenation reactor is sequentially loaded with the hydrodechlorination catalyst prepared in Preparation Example 2 and the RJW-3 hydrodeoxygenation catalyst, and the volume contents of the two are 35% and 65%, respectively. The hydrodechlorination catalyst and the hydrodeoxygenation catalyst are sulfurized. Straight-run kerosene containing 2% dimethyl disulfide by mass is used as the sulfurized oil, and the temperature is increased from 110°C to 230°C at a rate of 20°C / h, and maintained for 6h; then the temperature is increased to 360°C at a rate of 20°C / h, and maintained for 6h. After the hydrogen and the bio-oil raw material (composition is shown in Table 2) are mixed, they enter the hydrogenation reactor and contact with the hydrodechlorination catalyst and the hydrodeoxygenation catalyst in turn for hydrogenation reaction. The reaction product is separated by gas and liquid to obtain a hydrorefined oil product and reaction water. The operating conditions of the hydrogenation reactor are as follows: the average temperature of the hydrodechlorination reaction bed is 270°C, the average temperature of the hydrodeoxygenation reaction bed is 350°C, the pressure is 7MPa, the bio-oil flow rate is 100mL / h, and the hydrogen flow rate is 120L / h.

[0104] The organic chlorine content, oxygen content in the hydrorefined oil after different reaction times and the inorganic chlorine content in the separated water were analyzed. The results are shown in Table 3.

[0105] Example 3

[0106] The method of Example 1 was followed, except that the hydrodechlorination catalyst prepared in Preparation Example 3 was used instead.

[0107] The organic chlorine content, oxygen content in the hydrorefined oil after different reaction times and the inorganic chlorine content in the separated water were analyzed. The results are shown in Table 3.

[0108] Comparative Example 1

[0109] The method of Example 1 was followed, except that the hydrodechlorination catalyst prepared in Comparative Preparation Example 1 was used instead.

[0110] The organic chlorine content, oxygen content in the hydrorefined oil after different reaction times and the inorganic chlorine content in the separated water were analyzed. The results are shown in Table 3.

[0111] Comparative Example 2

[0112] The method of Example 1 is followed, except that

[0113] The total loading volume of the catalyst in the fixed bed hydrogenation reactor is 100 mL. Along the logistics direction, the fixed bed hydrogenation reactor is sequentially loaded with the hydrodeoxygenation catalyst RJW-3 (produced by Changling Catalyst Factory) and the inert ceramic balls, and the volume contents of the two are 70% and 30%, respectively. After the hydrogen and the bio-oil raw material are mixed, they enter the hydrogenation reactor and sequentially contact with the RJW-3 and the ceramic balls for hydrogenation reaction.

[0114] The organic chlorine content, oxygen content in the hydrorefined oil after different reaction times and the inorganic chlorine content in the separated water were analyzed. The results are shown in Table 3.

[0115] Comparative Example 3

[0116] The total loading volume of the catalyst in the fixed-bed hydrodeoxygenation reactor is 100 mL. Along the logistics direction, the fixed-bed hydrodeoxygenation reactor is sequentially loaded with hydrodeoxygenation catalyst RJW-3 (produced by Changling Catalyst Factory) and inert porcelain balls, and the volume contents of the two are 70% and 30%, respectively. The post-dechlorination reactor is loaded with dechlorination adsorbent WGL-A (produced by Wenzhou Catalyst General Factory), and the catalyst loading amount is 100 mL. After hydrogen and bio-oil raw materials (composition shown in Table 2) are mixed, hydrodeoxygenation reaction and dechlorination reaction are carried out in sequence. The dechlorinated products are separated by gas and liquid to obtain refined oil products and reaction water. The operating conditions of the hydrogenation reactor are: pressure 6.4 MPa, bio-oil flow rate of 100 mL / h, hydrogen volume of 100 L / h, deoxygenation reaction bed average temperature of 320 ° C, and dechlorination reaction bed average temperature of 260 ° C.

[0117] The organic chlorine content, oxygen content in the hydrorefined oil after different reaction times and the inorganic chlorine content in the separated water were analyzed. The results are shown in Table 3.

[0118] Table 2

[0119] project Waste cooking oil Carbon content, %(w) 76.9 Hydrogen content, %(w) 11.7 Organic chlorine content, mg / kg 50 Sulfur content, mg / kg 49.6 Nitrogen content, mg / kg 72 Oxygen content, %(w) 11 Fe, mg / kg 20 Ni, mg / kg <1 V, mg / kg <1 Na, mg / kg 2.5 Ca, mg / kg 2.7 P, mg / kg 12 Si, mg / kg 2.3

[0120] Table 3

[0121]

[0122] Note: The organic chlorine content in oil products reflects the dechlorination activity of the hydrodechlorination catalyst;

[0123] The chlorine (HCl) content in the generated water reflects the chlorine adsorption activity of the hydrodechlorination catalyst.

[0124] It can be seen from the results in Table 3 that the method provided by the present invention has a significantly better dechlorination effect, can effectively solve the problem of chloride ion corrosion on the equipment during the processing of bio-oils, and can also refine and remove oxygen-containing compounds in the raw materials to produce high-quality refined oil products.

[0125] In Example 1-3, the organic chlorine content in the hydrorefined oil and the chlorine (HCl) content in the generated water after 100 hours and 1000 hours of reaction are both low, indicating that the catalyst used in the present invention has high dechlorination activity and chlorine adsorption activity. It can also be explained that the hydrodechlorination catalyst still maintains a high chlorine capacity after 1000 hours of reaction. The hydrodechlorination catalyst of the present invention has high stability and can avoid device corrosion and pipeline blockage caused by high liquid phase chlorine content during long-term operation.

[0126] In comparison, although the catalysts in Comparative Examples 1-3 have higher dechlorination activity, the chlorine content in the generated water in Comparative Example 1 after 100 hours of reaction is relatively high, reaching 45.3 mg / L. The chlorine content in the generated water in Comparative Example 2 after 100 hours of reaction is very high, reaching 220 mg / L. Although the hydrodeoxygenation reaction product in Comparative Example 3 is dechlorinated by passing through a dechlorination reactor, the chlorine content in the water after 100 hours of reaction is still as high as 168 mg / L. Moreover, the chlorine content of the generated water in Comparative Examples 1, 2 and 3 is even higher after 1000 hours of reaction. Such a high chlorine content is bound to cause serious corrosion to the device.

[0127] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for hydrogenating chlorine-containing biological oils and fats, the method comprising: (1) dechlorinating the chlorine-containing bio-oil with hydrogen under the action of a hydrodechlorination catalyst to obtain a stream W; (2) subjecting the stream W to a deoxygenation reaction under the action of a hydrodeoxygenation catalyst; The hydrodechlorination catalyst comprises a modified carrier and an active metal component supported on the modified carrier, wherein the modified carrier comprises a carrier and an alkaline earth metal; the active metal component comprises a metal component of Group VIB and a metal component of Group VIII; the content of the alkaline earth metal is 20-50% by weight, calculated as oxide, based on the total weight of the modified carrier; Wherein, the breakthrough chlorine capacity of the hydrodechlorination catalyst is not less than 20%.

2. The processing method according to claim 1, wherein: The breakthrough chlorine capacity of the hydrodechlorination catalyst is 20-32%; Preferably, the content of alkaline earth metal is 20-40 wt %, more preferably 25-35 wt %, calculated as oxide, based on the total weight of the modified support; Preferably, the alkaline earth metal is magnesium and / or calcium, preferably magnesium.

3. The processing method according to claim 1, wherein: The specific surface area of ​​the modified carrier is 150-250m 2 / g, preferably 180-220m 2 / g; pore volume is 0.5-0.7cm 3 / g, preferably 0.55-0.65cm 3 / g; Preferably, the modified support does not have a spinel structure; Preferably, the support is alumina.

4. The processing method according to any one of claims 1 to 3, wherein: Based on the total weight of the hydrodechlorination catalyst, the content of the VIB Group metal component is 5-20wt%, preferably 5-15wt%, calculated as oxide; The content of the Group VIII metal component is 0.5-10wt%, preferably 0.8-5wt%; Preferably, the Group VIB metal component is molybdenum and / or tungsten; Preferably, the Group VIII metal component is nickel and / or cobalt.

5. The processing method according to any one of claims 1 to 4, wherein: The preparation method of the hydrodechlorination catalyst comprises the following steps: (a) mixing a carrier precursor and an alkaline earth metal precursor to form a mixture, and then optionally drying and calcining the mixture to obtain a modified carrier; (b) introducing active metal components onto the modified support obtained in step (a) by impregnation.

6. The processing method according to claim 5, wherein: The alkaline earth metal precursor is an alkaline earth metal oxide and / or an alkaline earth metal acid salt; Preferably, the alkaline earth metal acid salt is at least one selected from the group consisting of alkaline earth metal carbonates, alkaline earth metal nitrates, alkaline earth metal phosphates and alkaline earth metal sulfates, preferably alkaline earth metal carbonates, more preferably alkaline earth metal basic carbonates; Preferably, the carrier precursor is selected from at least one of pseudo-boehmite, boehmite, aluminum sol, amorphous hydrated aluminum oxide, aluminum oxide trihydrate and boehmite.

7. The processing method according to claim 5, wherein: The forming in step (a) is extrusion forming, spray forming, spheronization or tableting, preferably extrusion forming; Preferably, the drying conditions in step (a) include: a temperature of 60-280° C., preferably 110-200° C.; a time of 1-48 hours, preferably 2-12 hours; Preferably, the calcination conditions in step (a) include: a temperature of 300-600° C., preferably 350-550° C.; and a calcination time of 1-10 hours, preferably 2-8 hours.

8. The processing method according to any one of claims 1 to 7, wherein: The hydrodeoxygenation catalyst comprises alumina and a Group VIB metal component and a Group VIII metal component supported on the alumina; Preferably, based on the total weight of the hydrodeoxygenation catalyst, the content of the VIB group metal component is 5-30wt%, and the content of the VIII group metal component is 1-10wt% in terms of oxide; Preferably, in the hydrodeoxygenation catalyst, the Group VIB metal component is molybdenum and / or tungsten; Preferably, in the hydrodeoxygenation catalyst, the Group VIII metal component is nickel and / or cobalt.

9. The processing method according to any one of claims 1 to 8, wherein: The hydrodechlorination catalyst and the hydrodeoxygenation catalyst are loaded in different beds of a reactor, and along the logistics direction, the hydrodechlorination catalyst is located upstream of the hydrodeoxygenation catalyst; Preferably, the loading volume ratio of the hydrodechlorination catalyst to the hydrodeoxygenation catalyst is 1:1-20; Preferably, the conditions for the dechlorination reaction in step (1) include: a temperature of 200-350°C, preferably 250-300°C; a pressure of 3-15MPa, preferably 5-8MPa; a liquid hourly volume space velocity of 0.1-10h -1 , preferably 0.5-2h -1 ; The volume ratio of hydrogen to oil is 300-3000, preferably 800-1200; Preferably, the conditions for the deoxygenation reaction in step (2) include: a temperature of 200-400°C, preferably 280-350°C; a pressure of 3-15 MPa, preferably 5-8 MPa; a liquid hourly volume space velocity of 0.1-10 h -1 , preferably 0.5-2h -1 ; The volume ratio of hydrogen to oil is 300-3000, preferably 800-1200.

10. The processing method according to any one of claims 1 to 9, wherein: In the bio-oil, the content of organic chlorine is not less than 10 μg / g, preferably 50-100 μg / g; Preferably, in the bio-grease, the oxygen content is not higher than 15 wt %.

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