In-situ pre-vulcanized thermal cracking carbon black loaded bimetallic catalyst as well as preparation method and application thereof

Abstract

The invention provides an in-situ prevulcanization thermal cracking carbon black loaded bimetallic catalyst as well as a preparation method and application thereof, and belongs to the technical field of organic waste recycling. The bimetallic catalyst is prepared by taking a Zn-removed thermal cracking carbon material as a carrier, loading bimetallic metals of molybdenum and nickel by adopting an equivalent-volume impregnation method, and further performing in-situ activation and pre-vulcanization treatment on the bimetallic catalyst. According to the preparation method, the sulfur element in the thermal cracking carbon black is utilized to realize the in-situ pre-sulfuration process of the derivative hydrodesulfurization catalyst, so that the material cost required in the preparation process of the pre-sulfuration catalyst is controlled, the process complexity is reduced, the desulfurization efficiency can still be maintained at 85% or above after the obtained catalyst is recycled for three times, and the method is suitable for industrial production. A new thought is provided for high-value utilization of the thermal cracking carbon black and preparation of the carbon-based carrier presulfurization hydrodesulfurization catalyst.

Description

Technical Field

[0001] The invention belongs to the technical field of organic waste resource utilization, and relates to an in-situ presulfurized thermal cracking carbon black-loaded bimetallic catalyst, and a preparation method and application thereof. Background Art

[0002] The global tire sales volume is growing, which has put great pressure on the treatment of waste tires. Waste tires are usually composed of rubber (41-48%) (mainly composed of butadiene, styrene butadiene and natural polyisoprene), carbon black (20-28%) and steel wire (13-27%). Its natural decomposition process is estimated to be about 80 years, which poses a great challenge to the environment and ecological safety. At the same time, the carbon-rich characteristics of waste tires also make them have strong development prospects in the production of sustainable materials and alternative energy.

[0003] As a relatively mature method of treating waste tires, thermal cracking has seen significant development in the related industry in recent years. Since the main component of waste tires, namely rubber, is a hydrocarbon-based product, the thermal cracking oil derived from waste tires has a natural advantage in being directly used as gasoline and diesel; compared to other sustainable fuels derived from biomass, tire thermal cracking oil has obvious advantages in oxygen content, calorific value, hydrocarbon content and stability. However, transportation fuels have very strict standards for the S content in oil products, but due to the rubber vulcanization process, a large amount of S element remains in the waste cracking oil (about 20,000 ppm), and hydrodesulfurization is a necessary step in the process of converting crude oil to refined oil.

[0004] Crude oil can be hydrotreated to effectively remove impurities such as N, S, and O in the oil, reduce oil density, saturate the oil, and improve the thermal and oxidative stability of the oil. Ni-Mo is a common combination of catalytic hydrogenation active components, but when faced with the need to treat oil with a high S content, it is still difficult to resist its damage to the catalytic active center, and special catalyst design, such as presulfurization, is required to resist the impact of nitrogen- and sulfur-containing components on the catalytic activity.

[0005] In the existing hydrodesulfurization catalyst preparation method, the presulfurization process is usually implemented with the help of sulfur-containing metal salts (CN202211663513.1), sulfur-containing organic solvents (CN 202310465571.1; CN 202211716208.4), etc. In the presulfurization process, a separate sulfurization process is usually set up (CN202010656980.6). The above catalyst presulfurization method increases the material cost in the catalyst preparation process and the cumbersomeness of the production process. Therefore, how to provide a catalyst presulfurization method that can reduce the complexity of the process and realize the high-value utilization of thermal cracking carbon black is a problem that needs to be solved urgently in this field. Summary of the invention

[0006] The present invention provides a method for preparing an in-situ presulfurized pyrolysis carbon black-loaded bimetallic catalyst and its application. The method utilizes the sulfur element in the pyrolysis carbon black to realize the in-situ presulfurization process of the derived hydrodesulfurization catalyst, thereby controlling the material cost required in the preparation process of the presulfurized catalyst and reducing the process complexity, thus providing a new idea for the high-value utilization of pyrolysis carbon black and the preparation of carbon-based carrier presulfurized hydrodesulfurization catalyst.

[0007] In order to achieve the above-mentioned purpose, the present invention provides an in-situ presulfurized pyrolysis carbon black loaded bimetallic catalyst, which is prepared by using a de-Zn pyrolysis carbon material as a carrier, adopting an equal volume impregnation method, loading molybdenum and nickel bimetallics, and further subjecting it to an in-situ activation presulfurization treatment.

[0008] Preferably, the molybdenum loading is 1 to 5 wt.%, and the nickel loading is 1 to 5 wt.%.

[0009] Preferably, the method adopts an equal volume impregnation method, and is prepared by loading molybdenum and nickel bimetallic materials, comprising the following steps:

[0010] According to the bimetallic loading, chloride or nitrate of molybdenum and nickel are weighed and mixed evenly in deionized water to obtain a mixed solution;

[0011] The mixed solution and the Zn-removed thermal cracking carbon material are mixed and stirred, and impregnated with equal volumes until the solution and the carbon material are stirred into a paste to obtain a carbon material impregnated with a bimetallic;

[0012] The obtained bimetallic impregnated carbon material is calcined at 300-400°C for 2-4h in a reactor after N2 is evacuated; then, the inlet and outlet valves of the reactor are opened, and the bimetallic catalyst NiMoS / AC is obtained by activating and calcining the carbon material at 350-500°C for 2-4h in an atmosphere of a mixed gas of H2 and N2 with a flow rate of 2:8.

[0013] Preferably, the Zn-free pyrolysis carbon material is prepared by using pyrolysis carbon black as raw material, and is sequentially prepared by deashing to remove SiO2, activating and expanding the pores, and removing Zn. It is understandable that since the elemental S in the carbon black will volatilize at about 200°C after Zn removal, the Zn removal step needs to be after the activation step; in addition, the activation and expansion of the pores need to be performed after deashing to activate and expand the pores of the carbon material as much as possible; in summary, the preparation steps of the Zn-free pyrolysis carbon material are deashing to remove SiO2, activating and expanding the pores, and removing Zn treatment, and the order cannot be adjusted.

[0014] In the above scheme, the method used for deashing and removing SiO2 can be, for example: first, using 3M sodium hydroxide solution with 10 times the mass of carbon black to treat the solid product of waste tire pyrolysis at 80°C for 3h, and then separating the solid and liquid, and washing the solid product to pH = 7; secondly, using 3M hydrofluoric acid solution with 10 times the mass of carbon black to treat the solid product of waste tire pyrolysis at 80°C for 3h, separating the solid and liquid, and washing the solid product to pH = 7, to obtain the treated pyrolysis carbon black. It can be understood that the above scheme is a conventional method used in the art, but is not limited thereto. As long as it can effectively deash and remove SiO2, other methods recognized by those skilled in the art also belong to the protection scope of this application.

[0015] In the above scheme, the method used for activation and pore expansion can be, for example: drying the treated pyrolysis carbon black, grinding and mixing with the same mass of KOH, and placing in a tubular furnace; calcining the mixture of deashed pyrolysis carbon black and fully ground KOH in a tubular furnace, the atmosphere is nitrogen, the calcination temperature is 800°C, and the calcination time is 2h; the calcined product is stirred with 10 times the mass of 30% nitric acid solution for 3h, and then solid-liquid separation is performed, and the solid product is washed to pH=7 to obtain the pyrolysis carbon material after activation and pore expansion. It can be understood that the above scheme is a conventional method used in the art, but is not limited thereto. As long as it can effectively activate and expand the pores, other methods recognized by those skilled in the art also belong to the protection scope of this application.

[0016] In the above scheme, the method used for removing Zn from the activated and expanded pyrolysis carbon material can be, for example: first, using 0.6 times the mass of the carbon material, iron sulfate, 0.3 times the mass of the carbon material, acetic acid, stirring for 3 hours at 80°C, 10 times the mass of deionized water, and then solid-liquid separation, washing the solid product to pH = 7; finally, the Zn-removed pyrolysis carbon material is obtained. It can be understood that the above scheme is a conventional method used in the art, but is not limited thereto. As long as it can effectively remove Zn, other methods recognized by those skilled in the art also belong to the protection scope of this application.

[0017] Preferably, the pyrolysis carbon black is obtained from the solid product of the pyrolysis process of the waste tire pyrolysis factory, and after grinding, the product particle size is ≥1200 mesh.

[0018] The present invention also provides a method for hydrodesulfurization of waste tire pyrolysis oil, comprising the following steps:

[0019] Load waste tire pyrolysis oil and deionized water into a reactor, add the in-situ presulfurized thermal cracking carbon black-loaded bimetallic catalyst described in any of the above technical solutions, seal the flange, fill the reactor with 4MPa hydrogen, and seal the reactor to perform a hydrothermal catalytic reaction;

[0020] After the reaction is finished, the mixture is cooled to room temperature, the bimetallic catalyst and the reaction liquid phase are separated by centrifugation, the modified pyrolysis oil is collected, and the bimetallic catalyst is recovered;

[0021] Among them, after the bimetallic catalyst was recycled three times, the desulfurization efficiency could still be maintained above 85%.

[0022] Preferably, the catalytic hydrogenation waste tire pyrolysis oil obtained above can be used as fuel after being fully extracted with dichloromethane and the dichloromethane is removed by a rotary evaporator.

[0023] Preferably, the loading amount of the waste tire pyrolysis oil in the reactor is 5-10% of the volume of the reactor, and the addition amount of the bimetallic catalyst is 5-10% of the mass of the pyrolysis oil.

[0024] Preferably, the reactor is a batch stainless steel reactor, the hydrothermal catalytic reaction temperature is 350-450°C, and the reaction time is 60-120 min.

[0025] The present invention also provides an application of the in-situ presulfurized thermal cracking carbon black-loaded bimetallic catalyst described in any of the above technical solutions in the hydrodesulfurization of waste tire pyrolysis oil.

[0026] Preferably, after the bimetallic catalyst is recycled for three times, the desulfurization efficiency can still be maintained above 85%.

[0027] Compared with the prior art, the advantages and positive effects of the present invention are:

[0028] 1. The present invention uses Zn-free pyrolysis carbon material prepared by pyrolysis carbon black as a catalyst carrier and non-precious metal as the main catalyst, which not only realizes the high value and harmless treatment of pyrolysis solid products, but also realizes "waste treatment with waste";

[0029] 2. The present invention utilizes the prepared in-situ presulfurized pyrolysis carbon black-loaded bimetallic catalyst to hydrothermally catalyze the hydrodesulfurization of waste tire pyrolysis oil. Since the catalyst presulfurization uses the sulfur contained in the pyrolysis carbon black, the additional reagent consumption and operation steps required in the conventional catalyst presulfurization process are avoided;

[0030] 3. When the catalyst of the present invention is used for the hydrodesulfurization of waste tire pyrolysis oil, after three catalyst cycles, the desulfurization efficiency can still be maintained at 85.65%, which is significantly improved compared to the catalyst without presulfurization (desulfurization efficiency 69.51%), and the cycle stability is significantly improved. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Example 1

[0033] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel intermittent reactor with a capacity of 127mL, and 1g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 2wt.%, and the Mo loading was 2wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0034] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 1. The desulfurization efficiency is 82.06%.

[0035] Example 2

[0036] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel intermittent reactor with a capacity of 127mL, and 1g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 4wt.%, and the Mo loading was 4wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0037] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 1. The desulfurization efficiency is 78.03%.

[0038] Example 3

[0039] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel batch reactor with a capacity of 127mL, and 1g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 5wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0040] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 1. The desulfurization efficiency is 90.58%.

[0041] Example 4

[0042] 6g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel batch reactor with a capacity of 127mL, and 0.3g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 2wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 350°C for 60min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum desiccator; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0043] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 1. The desulfurization efficiency is 62.78%.

[0044] Example 5

[0045] 6g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel batch reactor with a capacity of 127mL, and 0.6g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 2wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 450°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum desiccator; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0046] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 1. The desulfurization efficiency is 92.38%.

[0047] Example 6

[0048] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel intermittent reactor with a capacity of 127mL, and 1g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 1wt.%, and the Mo loading was 5wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0049] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 1. The desulfurization efficiency is 67.71%.

[0050] Example 7

[0051] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel intermittent reactor with a capacity of 127mL, and 1g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 2wt.%, and the Mo loading was 5wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0052] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 1. The desulfurization efficiency is 80.72%.

[0053] Example 8

[0054] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel batch reactor with a capacity of 127mL, and 1g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 2wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum desiccator; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0055] The content of each element in the modified oil was tested by elemental analysis. The results are shown in Table 1. The desulfurization efficiency is 93.72%.

[0056] Example 9

[0057] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel intermittent reactor with a capacity of 127mL, and 1g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 1wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0058] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 1. The desulfurization efficiency is 91.93%.

[0059] Table 1 Element analysis results of waste tire pyrolysis oil catalyzed by presulfurized catalyst

[0060]

[0061]

[0062] Comparative Example 1

[0063] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel batch reactor with a capacity of 127mL; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged to collect the modified pyrolysis oil; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0064] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 2. The desulfurization efficiency is 70.85%.

[0065] Comparative Example 2

[0066] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel intermittent reactor with a capacity of 127mL, and 1g of catalyst (NiMo / AC) was added and the flange was sealed; wherein, the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 1wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel.

[0067] Among them, the preparation method of the catalyst NiMo / AC without presulfurization activation treatment is different from the preparation method of the in-situ presulfurized thermal cracking carbon black supported bimetallic catalyst of the present application in that after the carbon material impregnated with bimetallic is prepared, the preparation method is as follows (same as Comparative Examples 3-5):

[0068] The bimetallic carbon material was calcined at 150-200°C for 4 hours in a N2 atmosphere to remove the S element in the carbon material; then, it was activated and calcined at 500°C for 4 hours in a H2 and N2 mixed gas atmosphere with a flow rate of 2:8, and properly stored in a vacuum desiccator. The catalyst was named NiMo / AC.

[0069] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 2. The desulfurization efficiency is 89.69%.

[0070] Comparative Example 3

[0071] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel batch reactor with a capacity of 127mL, and 1g of catalyst (NiMo / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 2wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0072] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 2. The desulfurization efficiency is 94.17%.

[0073] Comparative Example 4

[0074] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel intermittent reactor with a capacity of 127mL, and 1g of catalyst (NiMo / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 2wt.%, and the Mo loading was 5wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0075] The content of each element in the modified oil was tested by elemental analysis. The results are shown in Table 2. The desulfurization efficiency is 77.58%.

[0076] Comparative Example 5

[0077] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel intermittent reactor with a capacity of 127mL, and 1g of catalyst (NiMo / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 1wt.%, and the Mo loading was 5wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the modified pyrolysis oil was collected; the catalyst was fully washed with deionized water and ethanol, fully dried at 70°C, and stored in a vacuum dryer; the modified pyrolysis oil was fully extracted with dichloromethane, and the dichloromethane was removed by a rotary evaporator to obtain the modified and upgraded fuel;

[0078] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 2. The desulfurization efficiency is 69.96%.

[0079] Table 2 Element analysis results of waste tire pyrolysis oil catalytically hydrogenated without presulfurization catalyst

[0080]

[0081] Example 10 (Based on the catalyst obtained in Example 8, used three times continuously)

[0082] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel batch reactor with a capacity of 127mL, and 1g of catalyst (NiMoS / AC) was added and the flange was sealed; wherein, the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 2wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the pyrolysis oil after modification was collected; the catalyst was fully washed with deionized water and ethanol, and fully dried at 70°C; then, the used catalyst was subjected to the above reaction again, and the catalyst recovery process was repeated; the catalyst was used continuously for 3 times; the oil obtained after the third reaction was stored and tested;

[0083] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 3. The desulfurization efficiency is 85.65%.

[0084] Comparative Example 6 (based on the catalyst obtained in Example 8, used 3 times continuously)

[0085] 10g of waste tire pyrolysis oil and 5g of deionized water were loaded into a stainless steel batch reactor with a capacity of 127mL, and 1g of catalyst (NiMo / AC) was added and the flange was sealed; wherein the catalyst active metal Ni loading was 5wt.%, and the Mo loading was 2wt.%; 4MPa of hydrogen was filled into the reactor and the reactor was sealed; the sealed reactor was subjected to catalytic hydrogenation reaction at 400°C for 120min; after the reaction was completed, the reactor was cooled to room temperature, the catalyst and the reaction liquid were centrifuged, and the pyrolysis oil after modification was collected; the catalyst was fully washed with deionized water and ethanol, and fully dried at 70°C; then, the used catalyst was subjected to the above reaction again, and the catalyst recovery process was repeated; the catalyst was used continuously for 3 times; the oil obtained after the third reaction was stored and tested;

[0086] The content of each element in the modified oil was tested by element analysis. The results are shown in Table 3. The desulfurization efficiency is 69.51%.

[0087] Table 3

[0088]

[0089] Example 8 Compared with Comparative Example 3, under the conditions of 5wt.% of the catalyst active metal Ni loading and 2wt.% of the Mo loading, the desulfurization efficiency (93.72%) of the presulfurized catalyst (NiMoS / AC) is not significantly different from that of the non-presulfurized catalyst (NiMo / AC); however, the corresponding Example 10 and Comparative Example 6 and the data in Table 3 show that the presulfurized catalyst has a significant advantage in cycle stability compared to the non-presulfurized catalyst. This is because compared to the non-presulfurized catalyst, the active center of the presulfurized catalyst is covered by part of the S element, although in the case of a single use, there is no significant difference in the hydrodesulfurization activity, and even compared with NiMoS / AC, the NiMo / AC activity shows a slight advantage; however, as the catalyst is used for a longer time, the active center of the catalyst NiMo / AC without presulfurization treatment is gradually destroyed by the S element in the cracking oil, and the presulfurized catalyst NiMoS / AC shows good anti-sulfur performance, so that after three cycles of use, NiMoS / AC can maintain a high activity.

[0090] In addition, compared with the comparative patents (CN 202211663513.1; CN 202310465571.1; CN202211716208.4), the presulfurization process of the catalyst directly uses the sulfur contained in the carbon black itself, without the introduction of exogenous sulfur, thereby maximizing the resource utilization of thermal cracking carbon black while reducing the production steps and costs; compared with the comparative patent (CN 202010656980.6, the presulfurization agent in this patent is hydrogen sulfide), its desulfurization efficiency for oil products is about 80%, while the present application improves the desulfurization efficiency (reaching 93.7%) while not using dangerous sulfides as presulfurization agents, which has obvious advantages in catalyst performance and preparation cost.

Claims

1. In-situ presulfurized thermal cracking carbon black supported bimetallic catalyst, characterized in that: The Zn-removed thermal cracking carbon material is used as a carrier, an equal volume impregnation method is adopted, molybdenum and nickel bimetallics are loaded, and further an in-situ activation presulfurization treatment is performed to prepare it.

2. The bimetallic catalyst according to claim 1, characterized in that The molybdenum loading is 1-5 wt.%, and the nickel loading is 1-5 wt.%.

3. The bimetallic catalyst according to claim 1, characterized in that The isovolumetric impregnation method is used to prepare the bimetallic material by loading molybdenum and nickel, which includes the following steps: According to the bimetallic loading, chloride or nitrate of molybdenum or nickel is weighed and mixed evenly in deionized water to obtain a mixed solution; The mixed solution and the Zn-removed thermal cracking carbon material are mixed and stirred, and impregnated with equal volumes until the solution and the carbon material are stirred into a paste to obtain a carbon material impregnated with a bimetallic; The obtained bimetallic impregnated carbon material is calcined at 300-400°C for 2-4h in a reactor after N2 is evacuated; then, the inlet and outlet valves of the reactor are opened, and the bimetallic catalyst NiMoS / AC is obtained by activating and calcining the carbon material at 350-500°C for 2-4h in an atmosphere of a mixed gas of H2 and N2 with a flow rate of 2:

8.

4. The bimetallic catalyst according to claim 1, characterized in that The Zn-free pyrolysis carbon material is prepared from pyrolysis carbon black as raw material through deashing to remove SiO2, activation and pore expansion, and Zn removal treatment.

5. The bimetallic catalyst according to claim 4, characterized in that Thermal cracking carbon black is taken from the solid product after the cracking process of the waste tire thermal cracking factory. After grinding, the product particle size is ≥1200 mesh.

6. A method for hydrodesulfurization of waste tire pyrolysis oil, characterized in that: The following steps are involved: Loading waste tire pyrolysis oil and deionized water into a reactor, adding the in-situ presulfurized thermal cracking carbon black-loaded bimetallic catalyst described in any one of claims 1 to 5, and then sealing the flange, filling the reactor with 4MPa hydrogen, and then sealing the reactor to perform a hydrothermal catalytic reaction; After the reaction is finished, the mixture is cooled to room temperature, the bimetallic catalyst and the reaction liquid phase are separated by centrifugation, the modified pyrolysis oil is collected, and the bimetallic catalyst is recovered; Among them, after the bimetallic catalyst was recycled three times, the desulfurization efficiency could still be maintained above 85%.

7. The method according to claim 6, characterized in that The loading amount of the waste tire pyrolysis oil in the reactor is 5-10% of the volume of the reactor, and the adding amount of the bimetallic catalyst is 5-10% of the mass of the pyrolysis oil.

8. The method according to claim 6, characterized in that The reactor is an intermittent stainless steel reactor, the hydrothermal catalytic reaction temperature is 350-450° C., and the reaction time is 60-120 min.

9. Use of the in-situ presulfurized thermal cracking carbon black-supported bimetallic catalyst according to any one of claims 1 to 5 in the hydrodesulfurization of waste tire pyrolysis oil.

10. The use according to claim 9, characterized in that: After the bimetallic catalyst has been used for three cycles, the desulfurization efficiency can still be maintained above 85%.

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