181 results about "Coal liquefaction" patented technology

The invention discloses a method for preparing a waterproof coiled material by using composite coal liquefaction residue asphalt. The method comprises the following steps: mixing matrix petroleum asphalt in a molten state with molten DCLR in a certain proportion to obtain DCLR modified asphalt; adding a certain amount of SBS into the DCLR modified asphalt, shearing for a period of time at a certain temperature, sequentially adding a certain amount of engine oil and rubber powder, continuously shearing for a period of time at a certain temperature, and finally developing for a period of time at a certain temperature to obtain the composite DCLR modified asphalt. Coating the composite DCLR modified asphalt on the upper and lower surfaces of a base to obtain a base body of the waterproof coiled material; the upper surface and the lower surface of the waterproof coiled material base body are coated with isolating membranes or covered with gravel and then cooled and formed. The problems that the added values of the coal liquefaction residues, the waste rubber powder and the waste engine oil are low, the compatibility of the coal liquefaction residues and the petroleum asphalt is poor, and the low-temperature performance and the anti-aging performance of the mixed asphalt are poor are solved.

The invention belongs to the technical field of foam carbon preparation, and particularly relates to a preparation method of coal liquefaction pitch-based foam carbon. The preparation method comprises the following steps: (1) contacting a template agent with alkali liquor for hydrolysis treatment to obtain a pretreated template; (2) contacting the pretreated template with asphalt slurry to obtain a foam carbon precursor; and (3) carrying out carbonization and activation treatment on the foam carbon precursor to obtain the coal liquefaction pitch-based foam carbon. The preparation method has the beneficial effects that the coal liquefied asphalt is used as a raw material to prepare the foam carbon, so that the resource conversion and utilization efficiency in the direct coal liquefaction process is improved, and the high-added-value utilization of coal resources is realized; the foam carbon obtained by the preparation method disclosed by the invention has the advantages of uniform pores and bubbles, high specific surface area, high aperture ratio and high strength, and is wide in application scene, low in preparation cost, simple in process and suitable for industrial production.

The invention discloses a direct coal liquefaction pump thermal wear prediction method considering a high temperature effect, and belongs to the technical field of fluid machinery and reliability engineering.The method comprises the steps that the high temperature effect is considered, a liquid phase control equation and a solid particle dynamic model are subjected to coupling iteration, and a solid-liquid two-phase flow numerical model is obtained; the method comprises the following steps: performing full flow field modeling on a fluid domain formed by flow passage components of a pump for direct coal liquefaction, and performing grid division on the fluid domain; constructing a heat-flow-solid multi-field coupling calculation system, and solving the solid-liquid two-phase flow numerical model by adopting a large eddy simulation method based on temperature correction and a discrete element method coupling method to obtain information of flow fields and particle fields at all positions in the pump; operation condition parameters are obtained, the thermal wear rate is obtained through a thermal wear rate calculation formula on the basis of flow field and particle field information of all positions in the pump, and the predicted wear amount of the flow passage component is obtained; and the prediction precision and applicability of the wear model are improved.

The invention discloses a direct coal liquefaction residue solvent extraction deliming method, refined asphalt and application, and relates to the technical field of solid waste resource treatment. According to the method, process conditions and process parameters are reasonably controlled, the thermal dissolution effect of an extraction agent and the liquefied residues is improved, a scale inhibitor composed of a multi-element alkyl organic matter, an auxiliary and coking washing oil is mixed with the extraction agent, then the ground liquefied residues are added into a material obtained through mixing, and the extraction agent and the liquefied residues are mixed uniformly. The slurry is prepared by controlling the stirring speed, the reaction temperature and the like; due to the addition of the scale inhibitor, the concentration of the residue extraction liquid is improved, and the treatment capacity and efficiency are enhanced; and a filter used for precision filtration adopts a stainless steel metal sintered filter element, so that the filter is resistant to higher temperature and pressure, the service life can be prolonged, and the stripping of viscous materials such as asphaltene in the liquefied residues is facilitated. The ultralow-ash refined asphalt prepared by the method can be used as a high-quality raw material of a high-end carbon material.

The invention belongs to the field of comprehensive utilization of coal chemical solid waste, and particularly relates to a treatment method of direct coal liquefaction residue raffinate, which comprises the following steps: (1) mixing direct coal liquefaction residue and an extraction agent to obtain an extraction system, and carrying out solid-liquid separation on the extraction system to obtain filtrate and filter residue; (2) carrying out distillation treatment on the filtrate to obtain asphalt; and (3) drying the filter residue to obtain a solid, and carrying out pyrolysis treatment on the solid to obtain pyrolytic oil. The method disclosed by the invention has the beneficial effects that the direct coal liquefaction residues are changed into products with industrial application values through a segmented processing method, so that an energy-saving, emission-reducing and resource-saving development mode is realized; a solution is provided for solving the problems of land occupation caused by accumulation and landfill of the direct coal liquefaction residues and serious damage to the ecological environment, and a new way with a wide market economic prospect is explored for realizing high-value utilization of liquefaction residue resources.

The invention relates to the field of asphalt production, and particularly discloses a preparation method of warm-mixed modified asphalt based on coal liquefaction oil residues, which comprises the following steps: S1, raw material pretreatment: pre-crushing the coal liquefaction oil residues until the particle size is less than or equal to 5mm, then refining the coal liquefaction oil residues to 200 meshes through an airflow mill, and then drying and dehydrating the coal liquefaction oil residues; the preparation method comprises the following steps: freezing SBS in a liquid nitrogen environment of-30 DEG C, and crushing the frozen SBS into 0.5-1mm particles by a hammer crusher; s2, pre-mixing the composite modifier by stages: in the first stage, adding the coal liquefaction oil residue, the aromatic oil and the rubber powder into a high-speed stirrer at 80 DEG C, and stirring; according to the preparation method of the warm-mixed modified asphalt based on the coal liquefaction oil residues, through the coal liquefaction oil residue superfine activation and SBS cryogenic grinding technology, the interfacial activity of the raw materials is improved, solid waste resource utilization is achieved, the modification cost is reduced, and meanwhile, by combining staged temperature control mixing and dissolving with the ultrasonic-assisted dispersion technology, the warm-mixed modified asphalt is prepared. The high-temperature rutting resistance and the water stability of the composite modified asphalt are improved.

The invention discloses a direct coal liquefaction catalyst suitable for mild coal liquefaction in the Hami region and a preparation method thereof, and relates to the technical field of direct coal liquefaction. The method comprises the following steps: firstly, preparing coal slurry with a certain mass fraction, and grinding and finely crushing the coal slurry; adding a surfactant into the obtained coal slurry to disperse the coal slurry; sequentially adding ferric salt and ammonia water into the dispersed coal slurry to obtain a first mixed solution; blowing oxygen into the first mixed solution, and after a period of time, adding a non-ferrous metal salt solution to obtain a second mixed solution; and filtering the second mixed solution, collecting solids, and drying the solids to obtain the product. According to the method, the dispersity and the catalytic effect of the iron-based catalyst can be effectively improved, and the coal liquefaction performance of coal with the inert component proportion being smaller than 2% under the mild liquefaction condition can be improved on the premise that a small amount of non-ferrous metal is used.

The invention discloses a method for recovering Mo and Fe from direct coal liquefaction oil residues, and belongs to the technical field of hydrometallurgy. The method comprises the steps of solvent extraction, roasting enrichment, wet leaching, extracting agent extraction, ammonia water reverse extraction and evaporative crystallization, and ammonium molybdate and Fe (OH) 3 are obtained. Wherein in the wet leaching process, a leaching aid and sulfuric acid are jointly used for leaching, so that Ca and Si in the oil residues are left in leaching residues, and Mo, Fe, Al and the like enter a solution. The method comprises the following steps: simultaneously extracting Mo and Fe from a solution by using an extracting agent, precipitating Fe in a Fe (OH) 3 state by using an ammonia water reverse extraction method, leaving Mo in a reverse extraction solution in the form of ammonium molybdate, and further evaporating and crystallizing the reverse extraction solution to obtain the ammonium molybdate. According to the method, two valuable metals Mo and Fe in the direct coal liquefaction oil residue can be effectively recovered, and resource recycling is facilitated.

The present disclosure discloses a molybdenum amine complex catalyst and a preparation method and use thereof, wherein, the method for preparing the molybdenum amine complex catalyst comprises the following steps: in the presence of a dispersion medium hydrocarbon oil, reacting a hexavalent molybdenum compound with at least one aliphatic amine compound having C4 or more carbon atoms to obtain an active metal catalyst precursor, and uniformly dispersing the active metal catalyst precursor in the dispersion medium hydrocarbon oil to obtain the molybdenum amine complex catalyst. When the molybdenum amine complex catalyst of the present disclosure is applied to the direct coal liquefaction reaction, it can significantly improve the conversion rate of coal and the conversion rate of asphaltene and preasphaltene to oil, allowing the required reaction pressure to be significantly reduced while achieving an oil yield comparable to that of the iron-based catalyst.

The invention relates to the technical field of coal liquefaction residue utilization, in particular to a nitrogen in-situ doped supercapacitor electrode material and a preparation method and application thereof. According to the invention, the coal liquefaction residue is used as a main raw material, and biomass such as enteromorpha with high nitrogen content is mixed with the coal liquefaction residue to obtain the nitrogen-doped high-end supercapacitor electrode material, so that the utilization rate and the additional value of the residue can be improved, the electrochemical performance of the electrode material is improved, and when the current density is 1A g <-1 >, the specific capacitance of the electrode can reach 200F g <-1 >; after 5000 times of charge and discharge cycles, the capacitance retention rate can reach 95.6%, and the material has good cycle characteristics and good stability, and has application prospects in capacitor energy storage devices and electrode materials.

The invention relates to the technical field of road asphalt modification, in particular to an asphalt modifier containing polyethylene and an asphalt mixture prepared from the asphalt modifier. The asphalt modifier containing polyethylene comprises the following components in parts by weight: 8-15 parts of matrix asphalt, 30-50 parts of coal liquefied asphalt, 30-50 parts of pretreated rubber powder, 1-4 parts of a solubilizer, 1-4 parts of a plasticizer and 2-4 parts of waste polyethylene plastic. The asphalt modifier containing polyethylene also comprises a component A: 0.3-3.0 parts by weight of modified basalt fiber. The asphalt modifier containing polyethylene is prepared through a mixing technology, compared with a traditional modifier, basic raw materials of the asphalt modifier are completely derived from solid waste resources, resource utilization of waste is achieved, and the preparation process is simplified.

The invention discloses an enhanced separation device and method for washing, solid removal and defoaming of a coal liquefaction system. The enhanced separation device comprises a vertical tank body, and a gas outlet and a solid-liquid outlet are formed in the top end and the bottom end of the vertical tank body respectively; a momentum fin unit, a micro-washing spraying device, an inlet separation distributor and a hydraulic spray head are sequentially arranged in the vertical tank body from top to bottom, and a material inlet is formed in the position, corresponding to the inlet separation distributor, of the side wall of the vertical tank body; the momentum fin unit and the micro-washing spraying device are positioned above the inlet separation distributor; the hydraulic spray head is obliquely upwards arranged on the inner wall below the inlet separation distributor; and the solid-liquid outlet is connected with a circulating pump through a pipeline. The device is compact in structure, the separation process is simplified, fine particles are trapped and separated only through gravity settling, the inertia effect and the like, and efficient and stable operation of the system is facilitated.

The invention relates to the field of road asphalt, and discloses high-modulus modified asphalt for improving road performance and a preparation method thereof, the modified asphalt comprises matrix asphalt, coal liquefied asphalt, modified rubber seed oil, ethylene-vinyl acetate copolymer and modified carbon nanotubes; the modified rubber seed oil is prepared from epoxy rubber seed oil and a carboxylated flame-retardant component prepared by reaction of amino trimethylphosphonic acid, trimethylolpropane and malonic acid; the modified carbon nano tube is prepared from a toluene-2, 4-diisocyanate isocyanated carbon nano tube and an aminated modifier through a reaction; the amination modifier is prepared by performing acylating chlorination grafting on 3-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid by using thionyl chloride and then grafting with p-phenylenediamine. According to the invention, the coal liquefaction asphalt, the modified rubber seed oil, the ethylene-vinyl acetate copolymer and the modified carbon nanotube are added into the matrix asphalt; the high and low temperature performance, the flame retardant performance and the anti-aging performance of the asphalt material can be improved.

The invention discloses a method for preparing a closed-pore-rich soft and hard carbon composite material from silk fibers and coal liquefied asphalt and sodium electricity application of the closed-pore-rich soft and hard carbon composite material, and belongs to the field of novel composite material preparation and electrochemical energy storage. The preparation method comprises the following steps: firstly, pre-carbonizing silk fibers to obtain pre-carbonized silk fibers; secondly, an open pore structure is constructed on the pre-carbonized silk fiber through chemical activation, and activated silk carbon fiber is obtained; thirdly, the surface of the activated silk carbon fiber is coated with coal liquefaction pitch through an impregnation method; and finally, co-carbonization is carried out to complete packaging of the open pores, and the composite material rich in the closed pore structure is obtained. The soft and hard carbon composite material disclosed by the invention has the characteristic of rich closed pores, and shows excellent specific capacity and low-voltage platform capacity; benefited from the core-shell synergistic effect of the inner-layer hard carbon and the outer-layer soft carbon, the conductivity and the sodium ion diffusion efficiency of the material are improved, so that the rate capability and the cycling stability of the material are enhanced; in addition, soft carbon packaging is used for replacing traditional ultrahigh-temperature carbonization to construct a closed-pore structure, and the preparation process is safe, controllable and energy-saving.

The invention discloses a method for complexing and separating n-alkanes in direct coal liquefaction oil, which comprises the following steps: 1) carrying out complexing reaction on the direct coal liquefaction oil and a complexing solution at 40-80 DEG C to obtain a complex suspension; 2) separating the complex suspension to obtain a complex and a filtrate; 3) demulsifying the filtrate at 20-60 DEG C, and separating out an oil phase to obtain an n-alkane removed oil product; wherein the complexing solution comprises a complexing agent, an activating agent and a solvent, the complexing agent is one or more of urea and thiourea, and the activating agent is low-carbon alcohol. The method effectively solves the problem that n-alkanes and isoalkanes in the direct coal liquefaction oil are difficult to separate.

The invention belongs to the technical field of capacitor carbon preparation, and particularly relates to coal liquefaction pitch-based heteroatom-doped spherical capacitor carbon and a preparation method thereof. According to the preparation method of the coal liquefied asphalt-based heteroatom-doped spherical capacitance carbon, the coal liquefied asphalt is adopted as a raw material, so that the production cost is reduced, clean and efficient utilization of coal resources is realized, and the specific surface area, the microporosity, the electrical conductivity, the structural stability and the capacitance performance of the traditional capacitance carbon are improved; the range of production raw materials is widened, the preparation process is simplified, and pollutants are reduced.

The invention discloses a modularized and multi-objective optimized carbon emission-energy consumption-cost collaborative optimization method for direct coal liquefaction oil preparation, and relates to the technical field of coal chemical industry technical optimization. Comprises: determining an accounting boundary; constructing a system model of the direct coal liquefaction oil production process; determining emission sources of the chemical process module and the self-contained power plant module; a module based on a direct coal liquefaction oil production system model is linked with a plurality of emission reduction technology interfaces to construct an emission reduction technology module; respectively establishing objective functions; defining constraint conditions of the target function; constructing a multi-objective optimization function of direct coal liquefaction oil production; relevant parameters of the multi-objective optimization model are collected; solving a Pareto optimal solution according to a Python code constructed by a multi-objective optimization problem of direct coal liquefaction for oil production; and outputting an optimization result, namely a Pareto optimal solution set. The modular design is adopted, emission sources of all links of direct coal liquefaction oil preparation are accurately recognized, and a plug-and-play interface is constructed for various emission reduction technologies.

The invention belongs to the technical field of spermidine preparation and application, and particularly relates to application of fusarium NF01 in preparation of spermidine and catalysis of lignite liquefaction. The fusarium NF01 is a fusarium strain Fusarium sp. NF01, and the fusarium strain NF01 is a fusarium strain NF01. Research finds that the fusarium strain Fusarium sp.NF01 can secrete spermidine synthetase, putrescine and decarboxylated S-adenosylmethionine are catalyzed by the spermidine synthetase to biologically synthesize spermidine, the spermidine acts on the lignite, then the lignite is liquefied, and the technical progress and application expansion in the field of coal development can be promoted.

The invention discloses a method for removing alkali liquor during shutdown of a direct coal liquefaction device. A system comprises a tank area alkali liquor tank, a coal liquefaction device alkali liquor buffer tank, a reaction heating furnace, a first reactor, a second reactor, a high-temperature and high-pressure separator, an alkali liquor discharge buffer tank, a foam cyclone separator and a defoamer. By adopting an innovative idea, the alkali liquor is discharged to the alkali liquor discharge buffer tank of the coal liquefaction device for buffering, degassing and defoaming, and then is pressurized and conveyed to the alkali liquor tank of the tank area for storage through the alkali liquor conveying pump of the coal liquefaction device, so that the aim of continuous shutdown and massive alkali liquor removal of the direct coal liquefaction device is fulfilled, the shutdown time is saved for enterprises, and the production efficiency is improved. And certain economic benefits are brought.

The present invention relates to the field of direct coal liquefaction, and discloses a catalytic coal-oil slurry and its preparation method, method of direct coal liquefaction, and use. The method includes mixing an oil-soluble molybdenum source, a solvent, pulverized coal, and an optional sulfur source to obtain the catalytic coal-oil slurry. When the catalytic coal-oil slurry is used for direct coal liquefaction, it can achieve a higher oil yield and reduce the production cost.

The invention discloses a hot standby method for a high-solid-content oil slurry heating furnace of a direct coal liquefaction device. The hot standby method comprises the following steps: cutting off communication between an inlet end of a standby furnace tube and a heating furnace inlet header pipe and communication between an outlet end of the standby furnace tube and a heating furnace outlet header pipe; the inlet end of the standby furnace tube is communicated with the flushing oil supply pipe, and the outlet end of the standby furnace tube is communicated with the flushing oil return pipe, so that the flushing oil fills the standby furnace tube and then returns to the flushing oil return pipe; igniting a burner nozzle of a radiation chamber of the standby hearth, and controlling the temperature of the standby hearth to a preset temperature by adjusting the flow of gas serving as fuel; and after the temperature of the standby hearth reaches the preset temperature, the oil feeding flow of flushing oil conveyed to the standby furnace tube and / or the oil returning flow of flushing oil entering the flushing oil returning tube are / is adjusted, so that the pressure of the standby furnace tube is controlled to reach the preset pressure. The heating furnace can be switched at the first time when having a fault, and stable operation is ensured.

The invention provides a direct coal liquefaction residue conversion method coupling multistage extraction and chemical chain gasification, and belongs to the technical field of coal liquefaction residue treatment. The method comprises the following steps: mixing the direct coal liquefaction residues with a primary extractant, and extracting to obtain a primary extract and a primary raffinate; mixing the first-stage raffinate with a second-stage extraction agent for extraction, repeating the operation step by step, mixing the last-stage raffinate with an inert carrier and alkali metal salt, drying, calcining to obtain an oxygen carrier, and crushing to control D50 of the oxygen carrier to be 74-150 [mu] m; and taking the raffinate of the plurality of stages or a mixture of the raffinate and coal as a gasification raw material, adding an oxygen carrier, controlling the oxygen-carbon ratio to be (0.2-0.8): 1, and carrying out gasification reaction. According to the method, the matching property of the obtained product and the downstream process is improved in a targeted manner, the ash content is directionally converted into the high-activity long-life oxygen carrier, the unconverted carbon of the raffinate is used as the gasification raw material and the like, so that the full-component efficient utilization of the coal liquefaction residues can be realized, the ash content treatment problem is effectively solved, and the operation cost of the chemical chain gasification process is reduced.

The invention provides a recycling hydrogen-donating solvent for direct coal liquefaction and a preparation method therefor and use thereof, the recycling hydrogen-donating solvent provided by the preparation method of the invention can be used for obtaining the recycling hydrogen-donating solvent with good hydrogen-donating capacity through a relatively simple process flow. The preparation method comprises the following steps: 1) carrying out first fractionation on a direct coal liquefaction oil to obtain liquefied medium oil and liquefied heavy oil; 2) feeding the liquefied heavy oil into a first hydrogenation reactor and carrying out a first-stage hydrogenation reaction; 3) feeding the liquefied medium oil and the liquefied heavy oil subjected to the first-stage hydrogenation reaction in the step 2) into a second hydrogenation reactor, and carrying out a second-stage hydrogenation reaction to obtain hydrogenated product oil; 4) performing second fractionation on the hydrogenated product oil to obtain medium-temperature solvent oil and high-temperature solvent oil; and 5) mixing the medium-temperature solvent oil and the high-temperature solvent oil to prepare the recycling hydrogen-donating solvent.

The invention provides a catalyst as well as a preparation method and application thereof. The catalyst comprises a carrier, the carrier comprises at least one pore channel, the pore channel is a hierarchical pore, and the size of the pore channel is 0.3-10 nanometers; at least part of the first active material is located in the pore channel, and the first active material comprises platinum and / or iridium. When the catalyst disclosed by the embodiment of the invention is applied to hydrogenation of coal tar and / or direct coal liquefaction oil, the coal tar and / or direct coal liquefaction oil enters the pore channels, so that the coal tar and / or direct coal liquefaction oil can be subjected to a ring-opening reaction, fuel with high heat sink can be obtained, and the obtained fuel can have high density, high freezing point and thermal stability at the same time and can be applied to hydrogenation of coal tar and / or direct coal liquefaction oil. The method is suitable for aerospace crafts.

This invention discloses a coal liquefaction residue-based warm-mix self-healing dual-function asphalt modifier and its preparation method, belonging to the field of road engineering materials technology. The modifier consists of the following components by mass percentage: plasma-activated coal liquefaction residue micropowder (40-60%), warm-mix functional agent (10-20%), self-healing microcapsules (15-25%), interface reinforcing agent (5-10%), and coupling agent (2-5%). The plasma-activated coal liquefaction residue micropowder has a particle size of 0.15 mm, a specific surface area of ​​300-400 m² / g, and a surface hydroxyl content of 1.2-2.0 mmol / g. Its porous structure is used to adsorb and slowly release the warm-mix functional agent, and also serves as a carrier for the microcapsules. The warm-mix functional agent is a compound of sodium alkylbenzene sulfonate / polyoxyethylene ether and glyceryl stearate / methyl oleate, which are oriented at 120-130℃ to form a lubricating interface layer, reducing the viscosity of the asphalt mortar by more than 30%. The self-healing microcapsules use polyurethane as the shell material and contain asphalt recycler, sulfur, and plasticizer in the core material. They can rupture and release the core material when microcracks propagate.

The present disclosure relates to a pressure reducing control valve and a coal liquefaction device, wherein the pressure reducing control valve comprises a valve body, a valve seat and a valve core, the valve seat is fixed inside the valve body, one end of the valve core is connected with an actuator, the other end can move towards or away from the valve seat, a plurality of sleeves are arranged inside the valve body and stacked in the vertical direction at the bottom of the valve seat, the top surface of the sleeve is formed with a through hole for the valve core to pass through, and the top of the sleeve is radially inwardly recessed to form a stepped surface, the opening of the upper one of the two adjacent sleeves is sleeved on the stepped surface of the lower sleeve, and flow holes are arranged on the sleeve, which can disperse the fluid pressure through the sleeve in layers, reduce the risk of single-point seal failure, and ensure coaxiality through the radial step cooperation to avoid valve core jamming. The first sealing gasket between the adjacent sleeves closely contacts with the mounting surface to form a sealing system, which can still maintain the overall sealing performance even if the single-layer seal fails.

The present invention provides a method for preparing and preheating an oil-coal slurry and a direct coal liquefaction process. The method of the present invention can achieve stable preheating of high-concentration oil-coal slurry, and can improve the operational stability and effective utilization rate of the device. The method comprises the following steps: (1) stirring and mixing materials including a heavy fraction and raw coal in an oil-coal slurry preparation tank to obtain an oil-coal slurry premix; (2) feeding the oil-coal slurry premix, a first light fraction, and hydrogen into a coal slurry heater I and heating them to 250-300°C to obtain an oil-coal slurry intermediate material; (3) feeding the oil-coal slurry intermediate material and the second light fraction obtained in step (2) into a coal slurry heater II and heating them to 350-400°C to obtain an oil-coal slurry to be liquefied, and the oil-coal slurry to be liquefied is used to be transported to a liquefaction reactor of the direct coal liquefaction process.

The application provides a preparation method of a sodium ferrous disulfide catalyst and application of the sodium ferrous disulfide catalyst in direct coal liquefaction, and relates to the technical field of coal liquefaction.The preparation method of the sodium ferrous disulfide catalyst comprises the following steps: mixing a ferric salt solution and a Na2S solution or a NaHS solution, performing a precipitation reaction, and obtaining a precipitation reaction system; and aging the precipitation reaction system, and performing solid-liquid separation to obtain the sodium ferrous disulfide catalyst.The preparation method of the NaFeS2 catalyst is simple in process, mild in preparation condition, does not need heating and pressurization, has a wide source of raw materials, is low in cost, and is easy to be industrialized.The obtained sodium ferrous disulfide has high catalytic activity as a catalyst for direct coal liquefaction, and the oil yield and conversion rate of direct coal liquefaction are higher than those of a catalyst used in the industry at present.

The present application provides a solvent oil, a preparation method and use thereof. The solvent oil is used for refining treatment of coal liquefied pitch, has good solid-liquid separation effect, is easy to recycle and reuse, can obtain refined pitch with high yield, low ash content and low quinoline insoluble content under the condition of low solvent oil consumption, and can meet the application requirements of high-end carbon materials. The solvent oil contains C 10 ~C 16 paraffins, cycloparaffins with ring number of 1-3, monocyclic aromatic hydrocarbons, bicyclic aromatic hydrocarbons and tricyclic aromatic hydrocarbons; the content of the C 10 ~C 16 paraffins is 5.0-10.5 wt%, the content of the cycloparaffins is 10.0-25.3 wt%, the content of the monocyclic aromatic hydrocarbons is 30.0-44.0 wt%, the content of the bicyclic aromatic hydrocarbons is 20.0-50.0 wt%, and the content of the tricyclic aromatic hydrocarbons is 0.5-5.0 wt%; the nitrogen content of the solvent oil is 200-2500 ppm, the sulfur content is 5-500 ppm, and the distillation range of the solvent oil is 170-350 DEG C.

The present invention relates to the technical field of separation of direct coal liquefaction oil, and provides a method for separating and purifying monocyclic aromatic hydrocarbons from direct coal liquefaction oil. The method comprises: (1) performing fractional distillation and composition analysis on direct coal liquefaction oil to determine a fraction having the highest content of monocyclic aromatic hydrocarbons; (2) removing low-carbon alkanes and cycloalkanes from a selected fraction by means of column chromatography; (3) separating toluene, a monocyclic aromatic hydrocarbon mixture, and high-carbon alkanes by means of an atmospheric and vacuum distillation column; (4) purifying ethylbenzene from the monocyclic aromatic hydrocarbon mixture by means of an extractive distillation column; and (5) purifying p-xylene by means of a solvent recovery column. The separation method provided by the present invention can make full use of the composition characteristics of direct coal liquefaction oil to obtain two or three high-purity monocyclic aromatic hydrocarbon monomers at a time without introducing additional chemical reaction steps, showing significant economic and environmental benefits.