Continuous preparation method of erucyl amide and adopted device

Abstract

The invention belongs to the technical field of erucyl amide production, and particularly relates to a continuous preparation method of erucyl amide and an adopted device. The invention provides a continuous preparation method of erucyl amide. Compared with a traditional intermittent method, the continuous preparation method provided by the invention has the advantages that continuous and automatic production of erucyl amide can be realized, the process is simpler and more convenient, meanwhile, the product stability and consistency of erucyl amide can be further improved, and the production efficiency is improved. The invention also provides a device for continuously preparing erucyl amide. According to the device provided by the invention, each production process adopts DCS centralized control, automatic feeding, automatic temperature control, automatic discharging, automatic regulation and control of pressure, flow, liquid level and rotating speed and online supervision and detection, and full-process automatic precise control is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of erucamide production, and specifically relates to a continuous preparation method of erucamide and a device used therein. Background Art

[0002] Erucic acid amide (structural formula: CH 3 -(CH 2 ) 7 CH=CH-(CH 3 ) 11 CONH 2 ) is an advanced long-carbon-chain bio-based material additive. It is currently being promoted and applied in automotive interior materials, lithium battery isolation films, protective films, electronic information materials, smart watches, fruit cling film, liquid packaging films such as milk and beverages, food and pharmaceutical packaging materials, refrigerator inner cavity panels and home appliance materials, mask (meltblown cloth) materials, leather surface treatment agents, biodegradable materials and disposable sanitary materials. It requires little addition and has good effects.

[0003] The erucamide product is obtained by an intermittent production process using erucic acid extracted from natural oils (rapeseed oil) as the main raw material, which mainly includes: erucic acid and ammonia are subjected to an amidation reaction in the presence of a catalyst. Commonly used catalysts include activated alumina or chromatographic silica gel. Ammonium erucate is first generated and then dehydrated to generate erucamide. The reaction temperature is 170-200°C, the pressure is 0.3-0.5MPA, and the reaction time is 12-16 hours. The introduction rate of ammonia is controlled to maintain the reaction pressure, and the water (steam) and unreacted ammonia generated by the reaction are intermittently discharged to complete the dehydration reaction of the ammonium salt. The reaction product (crude amide) is then dissolved in ethanol under stirring, a small amount of decolorizing agent (activated carbon) is added, the residue is filtered out, and the product is purified and refined by cooling crystallization and recrystallization. The entire process is intermittent operation, continuous production and automation are low, the quality is unstable, and the cost is high. Summary of the invention

[0004] The object of the present invention is to provide a continuous preparation method of erucamide and a device used therein. The method provided by the present invention can further improve the stability and consistency of erucamide and improve production efficiency.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a continuous preparation method of erucamide, comprising the following steps:

[0007] Continuously introducing erucic acid, ammonia and a catalyst into a reactor for amidation reaction to obtain a reaction material;

[0008] The reaction material is subjected to gas-liquid separation to obtain a gas phase material and a liquid phase product;

[0009] Condensing and separating the gaseous material, and returning the obtained ammonia to the amidation reaction for recycling;

[0010] The liquid phase product is distilled to obtain erucic acid and crude erucamide, and the erucic acid is returned to the amidation reaction for recycling;

[0011] The crude erucic acid amide is separated by short-path distillation to obtain the erucic acid amide.

[0012] Preferably, the mass flow ratio of erucic acid to ammonia is 400-900:40-90.

[0013] Preferably, the catalyst is a liquid phase catalyst; in terms of mass percentage, the liquid phase catalyst comprises 40-60% polybutyl titanate, 30-50% butyl silicate and 10-20% polyethylene glycol;

[0014] The added mass of the liquid phase catalyst is 0.3-0.6% of the mass of the erucic acid.

[0015] Preferably, the temperature of the amidation reaction is 180-210° C., the insulation time is 30-60 min, and the pressure is 0.8-1.2 MPa.

[0016] Preferably, the distillation temperature is 195-225° C.; the distillation is carried out under vacuum conditions, with a vacuum degree of ≤8 Pa;

[0017] The temperature of the short-path distillation separation is 205-220° C.; the short-path distillation separation is carried out under vacuum conditions, with a vacuum degree of ≤6Pa.

[0018] The present invention also provides a device used in the continuous preparation method of erucic acid amide described in the above technical solution, comprising a multi-tubular reactor, a gas-liquid separator, a distillation tower and a short-path distiller which are connected in sequence;

[0019] The gas-liquid separator is also connected to the condensation separator;

[0020] The device also includes a DCS control system, which is automatically connected to the multi-tubular reactor, the gas-liquid separator, the rectification tower, the short-range distiller and the condensation separator.

[0021] Preferably, the multi-tubular reactor is a tube-in-tube structure, comprising a plurality of tubes arranged in parallel;

[0022] A spoiler is provided inside each tube row, and a constriction is provided in the middle of each tube row;

[0023] The multi-tubular reactor is provided with an upper feed inlet and a bottom discharge outlet;

[0024] The bottom discharge port is communicated with the feed port of the gas-liquid separator.

[0025] Preferably, the gas-liquid separator comprises a liquid phase discharge port and a gas phase discharge port;

[0026] The liquid phase discharge port is in communication with the distillation tower;

[0027] The gas phase discharge port is communicated with the condensation separator.

[0028] Preferably, the distillation tower includes a fractionation section and a rectification section from top to bottom;

[0029] The fractionation section includes a gas phase condenser and a collector from top to bottom;

[0030] The rectification section includes a distributor and a falling film heater from top to bottom;

[0031] A feed inlet is arranged in the middle of the distillation tower, and the feed inlet is communicated with the liquid phase discharge port and the distributor respectively.

[0032] Preferably, the short-path distiller is a short-path molecular distiller, and a rotary scraping mode structure is adopted inside the short-path molecular distiller.

[0033] The present invention provides a continuous preparation method of erucic acid amide, comprising the following steps: continuously introducing erucic acid, ammonia and a catalyst into a reactor for amidation reaction to obtain a reaction material; performing gas-liquid separation on the reaction material to obtain a gas phase material and a liquid phase product; condensing and separating the gas phase material, and returning the obtained ammonia to the amidation reaction for recycling; rectifying the liquid phase product to obtain erucic acid and crude erucic acid amide, and the erucic acid is returned to the amidation reaction for recycling; performing short-path distillation separation on the crude erucic acid amide to obtain the erucic acid amide. Compared with the traditional intermittent method, the continuous preparation method provided by the present invention can realize the continuous and automated production of erucic acid amide, and the process is simpler, and at the same time, the product stability and consistency of erucic acid amide can be further improved, and the production efficiency can be improved.

[0034] The present invention also provides a device for continuously preparing erucic acid amide, comprising a multi-tubular reactor, a gas-liquid separator, a distillation tower and a short-range distiller connected in sequence; the gas-liquid separator is also connected to a condensation separator; the device also includes a DCS control system, and the DCS control system is automatically connected to the multi-tubular reactor, the gas-liquid separator, the distillation tower, the short-range distiller and the condensation separator. In the device provided by the present invention, each production equipment process is centrally controlled by a DCS system, with automatic feeding, automatic temperature control, automatic discharging, automatic regulation of pressure, flow, liquid level and speed, online supervision and detection, and automatic and precise control of the entire process, thereby improving the stability and consistency of the product, as well as production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention provides a schematic diagram of the continuous preparation process of erucamide. DETAILED DESCRIPTION

[0036] The present invention provides a continuous preparation method of erucamide, comprising the following steps:

[0037] Continuously introducing erucic acid, ammonia and a catalyst into a reactor for amidation reaction to obtain a reaction material;

[0038] The reaction material is subjected to gas-liquid separation to obtain a gas phase material and a liquid phase product;

[0039] Condensing and separating the gaseous material, and returning the obtained ammonia to the amidation reaction for recycling;

[0040] The liquid phase product is distilled to obtain erucic acid and crude erucamide, and the erucic acid is returned to the amidation reaction for recycling;

[0041] The crude erucic acid amide is separated by short-path distillation to obtain the erucic acid amide.

[0042] The invention continuously introduces erucic acid, ammonia and a catalyst into a reactor to carry out an amidation reaction to obtain a reaction material.

[0043] In the present invention, the ammonia is preferably dried before the reaction to obtain anhydrous ammonia. In the present invention, the mass flow ratio of erucic acid and ammonia is preferably 400-900:40-90, the mass flow of erucic acid is preferably 400-900 kg / h, and the mass flow of ammonia is preferably 40-90 kg / h. In the present invention, the catalyst is preferably a liquid phase catalyst; in terms of mass percentage, the liquid phase catalyst preferably includes 40-60% polybutyl titanate, 30-50% butyl silicate and 10-20% polyethylene glycol; the added mass of the liquid phase catalyst is preferably 0.3-0.6% of the mass of the erucic acid. In the present invention, the polyethylene glycol is preferably any one of PEG200, PEG300, PEG400, PEG500, PEG600, PEG700 and PEG800.

[0044] In the present invention, the temperature of the amidation reaction is preferably 180-210° C., the insulation time is preferably 30-60 min, and the pressure is preferably 0.8-1.2 MPa.

[0045] After obtaining the reaction material, the present invention performs gas-liquid separation on the reaction material to obtain a gas phase material and a liquid phase product. The present invention has no particular limitation on the gas-liquid separation process, and a method well known to those skilled in the art can be used.

[0046] After obtaining the gaseous material, the present invention condenses and separates the gaseous material, and the obtained ammonia is returned to the amidation reaction for recycling.

[0047] In the present invention, the ammonia gas is preferably dried before being returned to the amidation reaction. In the present invention, the separation preferably further comprises obtaining ammonia-containing wastewater, and the ammonia-containing wastewater is subjected to subsequent wastewater treatment.

[0048] After obtaining the liquid phase product, the present invention performs rectification on the liquid phase product to obtain erucic acid and crude erucamide, and the erucic acid is returned to the amidation reaction for recycling.

[0049] In the present invention, the temperature of the distillation is preferably 195-225°C; the distillation is preferably carried out under vacuum conditions, and the vacuum degree is preferably ≤8 Pa. In the present invention, the distillation is preferably carried out in a distillation tower, and the distillation tower preferably includes a fractionation section and a distillation section from top to bottom, the temperature of the fractionation section is preferably 195-205°C, and the temperature of the distillation section is preferably 215-225°C.

[0050] In the present invention, the erucic acid is preferably subjected to degassing, dehydration and preheating treatments in sequence before being returned to the amidation reaction.

[0051] After obtaining the crude erucic acid amide, the present invention performs short-path distillation separation on the crude erucic acid amide to obtain the erucic acid amide.

[0052] In the present invention, the temperature of the short-path distillation separation is preferably 205-220°C; the short-path distillation separation is preferably carried out under vacuum conditions, and the vacuum degree is preferably ≤6 Pa. In the present invention, the short-path distillation separation is preferably carried out in a short-path molecular distiller, and the interior of the short-path molecular distiller preferably adopts a rotary scraping mode structure.

[0053] In the present invention, after the short-range distillation separation, liquid erucamide and heavy components are preferably obtained; the liquid erucamide is preferably cooled, granulated and automatically packaged in sequence to obtain an erucamide finished product; the heavy components are preferably recovered and used as asphalt additives.

[0054] The present invention also provides a device used in the continuous preparation method of erucic acid amide described in the above technical solution, comprising a multi-tubular reactor, a gas-liquid separator, a distillation tower and a short-path distiller which are connected in sequence;

[0055] The gas-liquid separator is also connected to the condensation separator;

[0056] The device also includes a DCS control system, which is automatically connected to the multi-tubular reactor, the gas-liquid separator, the rectification tower, the short-range distiller and the condensation separator.

[0057] In the present invention, the multi-tube reactor is preferably a tube-in-tube structure, preferably comprising a plurality of tubes arranged in parallel; the diameter of each tube is preferably Φ45-Φ76 mm or Φ32-Φ50 mm, and the length is preferably 12-16 m; the diameter of the tube is preferably Φ1200-1600 mm, the height is preferably H12000-16000 mm, and the heat exchange area is preferably 80-120 m 2 . In the present invention, each tube array is preferably provided with a spoiler, and the middle of each tube array is preferably provided with a constriction; the diameter of the constriction is preferably Φ45 / Φ32mm (indicating that the diameter of the constriction is reduced from Φ45mm to Φ32mm, and similarly below) or Φ50 / Φ38mm or Φ65 / Φ50mm. In the present invention, the multi-tubular reactor is preferably provided with an upper feed port and a bottom discharge port; the bottom discharge port is preferably connected to the feed port of the gas-liquid separator.

[0058] In the present invention, the bottom discharge port is preferably provided with a back pressure valve for adjusting and maintaining the pressure required for the amidation reaction, and the pressure sensor is interlocked with the DCS system for automatic adjustment and control. In the present invention, the lower side of the multi-tubular reactor is preferably provided with a heat transfer oil inlet automatic adjustment valve for adjusting and controlling the temperature of the amidation reaction, and the temperature sensor is interlocked with the DCS system for automatic adjustment and control. In the present invention, the multi-tubular reactor also preferably includes an ammonia distributor and an erucic acid distributor as well as an imported mass flow meter and a material automatic adjustment valve for supporting use, and the average residence time of the reaction materials in the reactor is adjusted and controlled through the DCS control system and automatic adjustment and control is achieved.

[0059] In the present invention, the gas-liquid separator preferably includes a liquid phase discharge port and a gas phase discharge port; the liquid phase discharge port is preferably connected to the distillation tower; the gas phase discharge port is preferably connected to the condensation separator. In the present invention, the condensation separator is also preferably connected to an ammonia dryer for drying the recovered ammonia.

[0060] In the present invention, the distillation tower preferably includes a fractionation section and a rectification section from top to bottom. In the present invention, the fillers used in the fractionation section and the rectification section are preferably high-efficiency low-pressure drop orifice plate corrugated fillers. In the present invention, the tower body size of the distillation tower is preferably Φ1600×H18000mm (indicates a diameter of 1600mm and a height of 18000mm, similarly below); the size of the fractionation section (filler) is preferably Φ1600×H6000mm; the size of the rectification section (filler) is preferably Φ1600×H8000mm.

[0061] In the present invention, the fractionation section preferably includes a gas phase condenser and a collector from top to bottom, and the heat exchange area of ​​the gas phase condenser is preferably 60 to 90 m 2 The collector is used to collect the obtained erucic acid; the distillation section preferably includes a distributor and a falling film heater from top to bottom, and the heat exchange area of ​​the falling film heater is preferably 55 to 65 m 2 In the present invention, a feed inlet is preferably provided in the middle of the distillation tower, and the feed inlet is preferably connected to the liquid phase discharge port and the distributor, respectively. In the present invention, the falling film heater of the distillation tower is also preferably provided with a thermal oil heating automatic regulating valve, a temperature sensor, a pressure sensor and a mass flow meter, which are respectively connected to the DCS control system to realize automatic regulation and control.

[0062] In the present invention, the short-path distiller is preferably a short-path molecular distiller, and the interior of the short-path molecular distiller preferably adopts a rotary scraping mode structure. In the present invention, the evaporator area of ​​the short-path molecular distiller is preferably 12 to 20 m 2 The inner diameter is preferably Φ1000-1600mm, and the height is preferably H6000-7200mm; the speed of the rotating scraper is preferably 20-53rpm, and is adjusted and controlled by a variable frequency speed regulator; the interior of the short-range molecular distiller is also preferably provided with a built-in condenser, a material distributor and a mist separator, and the heat exchange area of ​​the built-in condenser is preferably 60-90m 2 In the present invention, the short-range molecular distiller is preferably also provided with a heat transfer oil heating automatic regulating valve, a temperature sensor, a pressure sensor and a mass flow meter, which are respectively connected to a DCS control system to realize automatic regulation and control. In the present invention, the short-range distiller adopts a rotary scraping mode structure to scrape the distilled material into an extremely thin turbulent flow film, which can improve the separation effect and reduce the heating time of the material.

[0063] In the present invention, the short-path distiller is preferably also connected to a cooling granulation tower and an automatic packaging device. In the present invention, the main fraction outlet of the short-path distiller is preferably connected to the material inlet of the cooling granulation tower, and the material outlet of the cooling granulation tower is preferably connected to the inlet of the automatic packaging device. In the present invention, the size of the cooling granulation tower is preferably a diameter of Φ3600mm, a height of H24000mm, and a cooling temperature is preferably ≤30°C. In the present invention, a fluidized bed cooler is also preferably provided in the cooling granulation tower. In the present invention, the automatic packaging equipment preferably includes automatic bag supply, automatic bagging, automatic weighing (quantitative), automatic folding and sewing, re-inspection weighing, automatic rejection, automatic coding, bag inversion conveying, belt conveying, robot stacking, full stack conveying and automatic pallet warehousing.

[0064] In the present invention, the entire preparation process is centrally controlled by a DCS system and monitored online to achieve automated and precise control of the entire process, thereby improving product stability and consistency, as well as production efficiency.

[0065] The continuous preparation method of erucamide is described below in conjunction with the device:

[0066] Continuously introducing erucic acid, ammonia and a catalyst into a multi-tubular reactor to carry out an amidation reaction to obtain a reaction material;

[0067] Passing the reaction material into a gas-liquid separator for gas-liquid separation to obtain a gas phase material and a liquid phase product;

[0068] The gas phase material is passed into a condensation separator, and the recovered ammonia gas is returned to the multi-tubular reactor for recycling;

[0069] The liquid phase product is passed into a distillation tower for distillation to obtain erucic acid and crude erucamide; the erucic acid is returned to the multi-tubular reactor for recycling;

[0070] Passing the crude erucic acid amide into a short-path distiller for distillation separation to obtain the erucic acid amide;

[0071] The multi-tubular reactor, gas-liquid separator, distillation tower, short-path distiller and condensation separator are respectively automatically connected to a DCS control system to achieve automatic control.

[0072] In the present invention, the total amide content of the erucic acid amide is ≥ 98.6%, wherein the erucic acid amide content is ≥ 88.3%, and the iodine value is 73-77gI 2 / 100g, melting point is 80.5~82.3℃, acid value ≤0.5mgKOH / g, color ≤100Hazen, moisture ≤0.05%, the quality is obviously better than China Petrochemical Corporation standard Q / SH0072 (total amide content ≥98%, of which erucamide content ≥88%, iodine value 72~77gI 2 / 100g, melting point 80-83°C, color ≤400 Hazen, moisture ≤0.1%).

[0073] Unless otherwise specified, the materials and equipment used in the present invention are all commercially available products in the art.

[0074] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a 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.

[0075] Example 1

[0076] use Figure 1 The device and process shown are used for the continuous preparation of erucamide;

[0077] Specifically:

[0078] Firstly, a multi-tubular reactor, a gas-liquid separator (liquid phase outlet), a rectifying tower, a short-range molecular still, a cooling granulation tower, and an automatic packaging device are sequentially connected, and the gas-liquid separator (gas phase outlet) is connected with a condensation separator and an ammonia dryer;

[0079] Continuously and uniformly feeding erucic acid, liquid phase catalyst and anhydrous ammonia into a multi-tubular reactor for amidation reaction to obtain reaction materials, wherein the flow rates of erucic acid, liquid phase catalyst and anhydrous ammonia are automatically adjusted and controlled by mass flow meter, automatic regulating valve and DCS control system interlocking, the flow rate of erucic acid is 510±5Kg / h, and the flow rate of anhydrous ammonia is 53±0.5Kg / h; the liquid phase catalyst is composed of polybutyl titanate, butyl silicate and polyethylene glycol (PEG600), wherein the content by mass percentage is: 42% of polybutyl titanate, 48% of butyl silicate and 10% of polyethylene glycol, and the materials are continuously fed by a mass metering pump according to 0.4% of the mass of erucic acid; the temperature of the amidation reaction is 195±2°C, the time is 45min, and the pressure is 0.9±0.05MPa;

[0080] The obtained reaction materials are continuously passed through a gas-liquid separator to separate gas phase materials and liquid phase products;

[0081] The obtained gas phase material is sent to a condensation separator to condense and separate ammonia and water vapor therein, and the ammonia is dehydrated by an ammonia dryer and then sent to a multi-tubular reactor for reuse;

[0082] The obtained liquid product is sent to a distillation tower to separate the unreacted free erucic acid, and then sent to a short-range molecular distiller to separate the liquid erucamide; the separated erucic acid is then sent to a multi-tubular reactor for reuse, and the evaporated erucamide is condensed and collected by a built-in condenser and then sent to a cooling and granulating tower for cooling and granulation, and then automatically packaged into a product, that is, a finished erucamide product is obtained;

[0083] The multi-tube reactor is a tube-in-tube structure. The raw materials undergo heat exchange and amidation reaction in the tube. It is equipped with an anhydrous ammonia distributor and a distributor for liquid phase material erucic acid (containing liquid catalyst). Each tube has a diameter of Φ45 mm and a length of 12 m. The diameter of the tube is Φ1400 mm and the height is H12000 mm. The heat exchange area is 90 m 2 , a spoiler is installed inside the tube array (inside the tube pass), a constriction (diameter is Φ45 / Φ32mm) is added in the middle of the tube array, the raw materials enter the multi-tubular reactor from the upper feed port, the lower part is provided with a bottom discharge port, and the outlet is equipped with a back pressure valve for adjusting and maintaining the pressure required for the reaction; a heat transfer oil inlet automatic regulating valve is installed at the lower part of the side of the multi-tubular reactor for adjusting and controlling the reaction temperature, and the average residence time of the material in the reactor is adjusted and controlled through the imported mass flow meter and the material automatic regulating valve, as well as the DCS control system;

[0084] The distillation tower is divided into an upper fractionation section and a lower distillation section. The fractionation section and the distillation section are respectively filled with high-efficiency low-pressure drop orifice plate corrugated packing. The diameter of the distillation tower body is Φ1600mm, the height is 18000mm, the fractionation section (packing) is Φ1600×H6000mm, the distillation section (packing) is Φ1600×H8000mm, and a gas phase condenser is provided at the upper part of the fractionation section, and the heat exchange area is 72m 2 A collector is provided at the bottom of the gas phase condenser to collect and recover the unreacted free erucic acid; a distributor is provided at the top of the distillation section and a falling film heater is provided at the bottom. The heat exchange area is 58m 2 The liquid product enters the distributor of the distillation section from the middle feed port of the tower. The unreacted erucic acid is condensed and collected by the gas phase condenser of the fractionator and then sent to the multi-tubular reactor for reuse. The material temperature of the distillation section is controlled at 198±2°C, and the vacuum degree at the top of the distillation tower is controlled at ≤5Pa; the material temperature of the distillation section is controlled at 220±3°C, and is adjusted and controlled by the lower falling film heater, and automatically adjusted and controlled by the thermal oil heating automatic regulating valve and the DCS control system;

[0085] The short-range molecular distiller is a rotary scraped film type, and the evaporator area of ​​the short-range molecular distiller is 16m2 The inner diameter is Φ1200mm, the height is 6500mm, the rotating scraper speed is 42rpm, and it is regulated and controlled by the frequency converter. The heat exchange area of ​​the built-in condenser is 64m 2 , and a material distributor and a mist separator are provided in the short-range molecular distiller. The distillation temperature of the short-range molecular distiller is 208±2℃, the system vacuum degree is ≤2Pa, and the distillation temperature is automatically adjusted and controlled by the thermal oil heating automatic regulating valve and the DCS control system;

[0086] The cooling granulation tower has a diameter of Φ3600 and a height of H24000mm, a cooling temperature of ≤26°C, and is equipped with a built-in fluidized bed cooler; the automatic packaging equipment consists of automatic bag supply, automatic bag loading, automatic weighing (quantitative), automatic folding and sewing, re-inspection and weighing, automatic rejection, automatic coding, bag inversion conveying, belt conveying, robot stacking, full stacking conveying, and automatic pallet warehousing, with a capacity of 60 to 80 bags per hour (25kg / bag);

[0087] During the whole process, the reaction temperature, distillation temperature and short-range molecular distillation temperature are automatically adjusted and controlled through the temperature sensor and the DCS system interlock. The reaction pressure, distillation system vacuum degree and short-range molecular distillation system vacuum are automatically adjusted and controlled through the pressure sensor and the DCS system interlock. The material conveying flow rate of each section is automatically adjusted and controlled through the mass flow meter and the automatic regulating valve interlocked with the DCS system. The speed of the rotating scraper of the short-range molecular distiller is automatically adjusted and controlled through the frequency converter and the DCS system interlock. The whole process is centrally controlled by the DCS system and online supervision and detection are adopted to realize full-process automated distillation control.

[0088] The total erucic acid content in the obtained erucic acid amide was 98.8%, of which the erucic acid amide content was 88.9%, and the iodine value was 76.2gI 2 / 100g, melting point is 81.7℃, acid value is 0.28mgKOH / g, color is 55Hazen, and moisture content is 0.03%.

[0089] Example 2

[0090] use Figure 1 The device and process shown are used for the continuous preparation of erucamide;

[0091] Specifically:

[0092] Firstly, a multi-tubular reactor, a gas-liquid separator (liquid phase outlet), a rectifying tower, a short-range molecular still, a cooling granulation tower, and an automatic packaging device are sequentially connected, and the gas-liquid separator (gas phase outlet) is connected with a condensation separator and an ammonia dryer;

[0093] Continuously and uniformly feeding erucic acid, liquid-phase catalyst and anhydrous ammonia into a multi-tubular reactor for amidation reaction to obtain reaction materials, wherein the flow rates of erucic acid, liquid-phase catalyst and anhydrous ammonia are automatically adjusted and controlled by mass flow meter, automatic regulating valve and DCS control system interlocking, the flow rate of erucic acid is 600±5Kg / h, and the flow rate of anhydrous ammonia is 61±0.5Kg / h; the liquid-phase catalyst is composed of polybutyl titanate, butyl silicate and polyethylene glycol (PEG600), wherein the content by mass percentage is: 45% polybutyl titanate, 40% butyl silicate and 15% polyethylene glycol, and the materials are continuously fed by a mass metering pump according to 0.45% of the mass of erucic acid; the temperature of the amidation reaction is 198±2°C, the time is 50min, and the pressure is 0.95±0.05MPa;

[0094] The obtained reaction materials are continuously passed through a gas-liquid separator to separate gas phase materials and liquid phase products;

[0095] The obtained gas phase material is sent to a condensation separator to condense and separate ammonia and water vapor therein, and the ammonia is dehydrated by an ammonia dryer and then sent to a multi-tubular reactor for reuse;

[0096] The obtained liquid product is sent to a distillation tower to separate the unreacted free erucic acid, and then sent to a short-range molecular distiller to separate the liquid erucamide; the separated erucic acid is then sent to a multi-tubular reactor for reuse, and the evaporated erucamide is condensed and collected by a built-in condenser and then sent to a cooling and granulating tower for cooling and granulation, and then automatically packaged into a product, that is, a finished erucamide product is obtained;

[0097] The multi-tube reactor is a tube-in-tube structure. The raw materials undergo heat exchange and amidation reaction in the tube. It is equipped with an anhydrous ammonia distributor and a distributor for liquid phase material erucic acid (containing liquid catalyst). Each tube has a diameter of Φ50 mm and a length of 12 m. The diameter of the tube is Φ1400 mm and the height is H12000 mm. The heat exchange area is 85 m 2 , a spoiler is installed inside the tube array (inside the tube pass), a constriction (diameter is Φ50 / Φ38mm) is added in the middle of the tube array, the raw materials enter the multi-tubular reactor from the upper feed port, the lower part is provided with a bottom discharge port, and the outlet is equipped with a back pressure valve for adjusting and maintaining the pressure required for the reaction; a heat transfer oil inlet automatic regulating valve is installed at the lower part of the side of the multi-tubular reactor for adjusting and controlling the reaction temperature, and the average residence time of the material in the reactor is adjusted and controlled through the imported mass flow meter and the material automatic regulating valve, as well as the DCS control system;

[0098] The distillation tower is divided into an upper fractionation section and a lower distillation section. The fractionation section and the distillation section are respectively filled with high-efficiency low-pressure drop orifice plate corrugated packing. The diameter of the distillation tower body is Φ1600mm, the height is 18000mm, the fractionation section (packing) is Φ1600×H6000mm, the distillation section (packing) is Φ1600×H8000mm, and a gas phase condenser is provided at the upper part of the fractionation section, and the heat exchange area is 72m 2 A collector is provided at the bottom of the gas phase condenser to collect and recover the unreacted free erucic acid; a distributor is provided at the top of the distillation section and a falling film heater is provided at the bottom. The heat exchange area is 58m 2 The liquid product enters the distributor of the distillation section from the middle feed port of the tower, and the unreacted erucic acid is condensed and collected by the gas phase condenser of the fractionator and then sent to the multi-tubular reactor for reuse. The material temperature of the distillation section is controlled at 198±2°C, and the vacuum degree at the top of the distillation tower is controlled at ≤5Pa; the material temperature of the distillation section is controlled at 222±3°C, and is adjusted and controlled by the lower falling film heater, and automatically adjusted and controlled by the thermal oil heating automatic regulating valve and the DCS control system;

[0099] The short-range molecular distiller is a rotary scraped film type, and the evaporator area of ​​the short-range molecular distiller is 16m 2 The inner diameter is Φ1200mm, the height is 6500mm, the rotating scraper speed is 42rpm, and it is regulated and controlled by the frequency converter. The heat exchange area of ​​the built-in condenser is 64m 2 , and a material distributor and a mist separator are provided in the short-range molecular distiller. The distillation temperature of the short-range molecular distiller is 210±2℃, the system vacuum degree is ≤2Pa, and the distillation temperature is automatically adjusted and controlled by the thermal oil heating automatic regulating valve and the DCS control system;

[0100] The cooling granulation tower has a diameter of Φ3600mm and a height of H24000mm, a cooling temperature of ≤28°C, and is equipped with a built-in fluidized bed cooler; the automatic packaging equipment consists of automatic bag supply, automatic bag loading, automatic weighing (quantitative), automatic folding and sewing, re-inspection and weighing, automatic rejection, automatic coding, bag inversion conveying, belt conveying, robot stacking, full stacking conveying, and automatic pallet warehousing, with a capacity of 60 to 80 bags per hour (25kg / bag);

[0101] During the whole process, the reaction temperature, distillation temperature and short-range molecular distillation temperature are automatically adjusted and controlled through the temperature sensor and DCS system interlocking. The reaction pressure, distillation system vacuum and short-range molecular distillation system vacuum are automatically adjusted and controlled through the pressure sensor and DCS system interlocking. The material delivery flow of each section is automatically adjusted and controlled through the mass flow meter and automatic regulating valve interlocking with the DCS system. The speed of the rotating scraper of the short-range molecular distillation device is automatically adjusted and controlled through the frequency converter and DCS system interlocking. The whole process is centrally controlled by the DCS system, and online supervision and detection are used to realize full-process automated distillation control.

[0102] The total erucic acid content in the obtained erucic acid amide was 98.6%, of which the erucic acid amide content was 88.5%, and the iodine value was 76.5gI 2 / 100g, melting point is 81.6℃, acid value is 0.31mgKOH / g, color is 60Hazen, and moisture content is 0.02%.

[0103] Example 3

[0104] use Figure 1 The device and process shown are used for the continuous preparation of erucamide;

[0105] Specifically:

[0106] Firstly, a multi-tubular reactor, a gas-liquid separator (liquid phase outlet), a rectifying tower, a short-range molecular still, a cooling granulation tower, and an automatic packaging device are sequentially connected, and the gas-liquid separator (gas phase outlet) is connected with a condensation separator and an ammonia dryer;

[0107] Continuously and uniformly feeding erucic acid, liquid phase catalyst and anhydrous ammonia into a multi-tubular reactor for amidation reaction to obtain reaction materials, wherein the flow rates of erucic acid, liquid phase catalyst and anhydrous ammonia are automatically adjusted and controlled by mass flow meter, automatic regulating valve and DCS control system interlocking, the flow rate of erucic acid is 720±5Kg / h, and the flow rate of anhydrous ammonia is 70±0.5Kg / h; the liquid phase catalyst is composed of polybutyl titanate, butyl silicate and polyethylene glycol (PEG600), wherein the content by mass percentage is: 40% polybutyl titanate, 50% butyl silicate and 10% polyethylene glycol, and the materials are continuously fed by a mass metering pump according to 0.4% of the mass of erucic acid; the temperature of the amidation reaction is 205±2°C, the time is 40min, and the pressure is 0.85±0.05MPa;

[0108] The obtained reaction materials are continuously passed through a gas-liquid separator to separate gas phase materials and liquid phase products;

[0109] The obtained gas phase material is sent to a condensation separator to condense and separate ammonia and water vapor therein, and the ammonia is dehydrated by an ammonia dryer and then sent to a multi-tubular reactor for reuse;

[0110] The obtained liquid product is sent to a distillation tower to separate the unreacted free erucic acid, and then sent to a short-range molecular distiller to separate the liquid erucamide; the separated erucic acid is then sent to a multi-tubular reactor for reuse, and the evaporated erucamide is condensed and collected by a built-in condenser and then sent to a cooling and granulating tower for cooling and granulation, and then automatically packaged into a product, that is, a finished erucamide product is obtained;

[0111] The multi-tube reactor is a tube-in-tube structure. The raw materials undergo heat exchange and amidation reaction in the tube. It is equipped with an anhydrous ammonia distributor and a distributor for liquid phase material erucic acid (containing liquid catalyst). Each tube has a diameter of Φ65mm and a length of 12m. The diameter of the tube is Φ1400mm and the height is H12000mm. The heat exchange area is 90m 2 , a spoiler is installed inside the tube array (in the tube pass), a constriction (diameter is Φ65 / Φ50mm) is added in the middle of the tube array, the raw materials enter the multi-tubular reactor from the upper feed port, the lower part is provided with a bottom discharge port, and the outlet is equipped with a back pressure valve for adjusting and maintaining the pressure required for the reaction; a heat transfer oil inlet automatic regulating valve is installed at the lower part of the side of the multi-tubular reactor for adjusting and controlling the reaction temperature, and the average residence time of the material in the reactor is adjusted and controlled through the imported mass flow meter and the material automatic regulating valve, as well as the DCS control system;

[0112] The distillation tower is divided into an upper fractionation section and a lower distillation section. The fractionation section and the distillation section are respectively filled with high-efficiency low-pressure drop orifice plate corrugated packing. The diameter of the distillation tower body is Φ1600mm, the height is 18000mm, the fractionation section (packing) is Φ1600×H6000mm, the distillation section (packing) is Φ1600×H8000mm, and a gas phase condenser is provided at the upper part of the fractionation section, and the heat exchange area is 72m 2 A collector is provided at the bottom of the gas phase condenser to collect and recover the unreacted free erucic acid; a distributor is provided at the top of the distillation section and a falling film heater is provided at the bottom. The heat exchange area is 58m 2 The liquid product enters the distributor of the distillation section from the middle feed port of the tower, and the unreacted erucic acid is condensed and collected by the gas phase condenser of the fractionator and then sent to the multi-tubular reactor for reuse. The material temperature of the distillation section is controlled at 203±2°C, and the vacuum degree at the top of the distillation tower is controlled at ≤5Pa; the material temperature of the distillation section is controlled at 218±3°C, and is adjusted and controlled by the lower falling film heater, and automatically adjusted and controlled by the thermal oil heating automatic regulating valve and the DCS control system;

[0113] The short-range molecular distiller is a rotary scraped film type, and the evaporator area of ​​the short-range molecular distiller is 16m 2 The inner diameter is Φ1200mm, the height is 6500mm, the rotating scraper speed is 42rpm, and it is regulated and controlled by the frequency converter. The heat exchange area of ​​the built-in condenser is 64m 2, and a material distributor and a mist separator are provided in the short-range molecular distiller. The distillation temperature of the short-range molecular distiller is 215±2℃, the system vacuum degree is ≤2Pa, and the distillation temperature is automatically adjusted and controlled by the thermal oil heating automatic regulating valve and the DCS control system;

[0114] The cooling granulation tower has a diameter of Φ3600mm and a height of H24000mm, a cooling temperature of ≤30°C, and is equipped with a built-in fluidized bed cooler; the automatic packaging equipment consists of automatic bag supply, automatic bag loading, automatic weighing (quantitative), automatic folding and sewing, re-inspection and weighing, automatic rejection, automatic coding, bag inversion conveying, belt conveying, robot stacking, full stacking conveying, and automatic pallet warehousing, with a capacity of 60 to 80 bags per hour (25kg / bag);

[0115] During the whole process, the reaction temperature, distillation temperature and short-range molecular distillation temperature are automatically adjusted and controlled through the temperature sensor and DCS system interlocking. The reaction pressure, distillation system vacuum and short-range molecular distillation system vacuum are automatically adjusted and controlled through the pressure sensor and DCS system interlocking. The material delivery flow of each section is automatically adjusted and controlled through the mass flow meter and automatic regulating valve interlocking with the DCS system. The speed of the rotating scraper of the short-range molecular distillation device is automatically adjusted and controlled through the frequency converter and DCS system interlocking. The whole process is centrally controlled by the DCS system, and online supervision and detection are used to realize full-process automated distillation control.

[0116] The total erucic acid content in the obtained erucic acid amide was 98.9%, of which the erucic acid amide content was 90.1%, and the iodine value was 75.8gI 2 / 100g, melting point is 81.1℃, acid value is 0.35mgKOH / g, color is 60Hazen, and moisture content is 0.02%.

[0117] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A continuous preparation method of erucamide, characterized in that: The following steps are involved: Continuously introducing erucic acid, ammonia and a catalyst into a reactor for amidation reaction to obtain a reaction material; The reaction material is subjected to gas-liquid separation to obtain a gas phase material and a liquid phase product; Condensing and separating the gaseous material, and returning the obtained ammonia to the amidation reaction for recycling; The liquid phase product is distilled to obtain erucic acid and crude erucamide, and the erucic acid is returned to the amidation reaction for recycling; The crude erucic acid amide is separated by short-path distillation to obtain the erucic acid amide.

2. The continuous preparation method according to claim 1, characterized in that: The mass flow ratio of erucic acid to ammonia is 400-900:40-90.

3. The continuous preparation method according to claim 1 or 2, characterized in that: The catalyst is a liquid phase catalyst; in terms of mass percentage, the liquid phase catalyst comprises 40-60% polybutyl titanate, 30-50% butyl silicate and 10-20% polyethylene glycol; The added mass of the liquid phase catalyst is 0.3-0.6% of the mass of the erucic acid.

4. The continuous preparation method according to claim 1, characterized in that: The temperature of the amidation reaction is 180-210° C., the insulation time is 30-60 min, and the pressure is 0.8-1.2 MPa.

5. The continuous preparation method according to claim 1, characterized in that: The distillation temperature is 195-225°C; the distillation is carried out under vacuum conditions, with a vacuum degree of ≤8Pa; The temperature of the short-path distillation separation is 205-220° C.; the short-path distillation separation is carried out under vacuum conditions, with a vacuum degree of ≤6Pa.

6. The device used in the continuous preparation method of erucamide according to any one of claims 1 to 5, characterized in that: It includes a multi-tubular reactor, a gas-liquid separator, a distillation tower and a short-path distiller which are connected in sequence; The gas-liquid separator is also connected to the condensation separator; The device also includes a DCS control system, which is automatically connected to the multi-tubular reactor, the gas-liquid separator, the rectification tower, the short-range distiller and the condensation separator.

7. The device according to claim 6, characterized in that The multi-tube reactor is a tube-in-tube structure, comprising a plurality of tubes arranged in parallel; A spoiler is provided inside each tube row, and a constriction is provided in the middle of each tube row; The multi-tubular reactor is provided with an upper feed inlet and a bottom discharge outlet; The bottom discharge port is communicated with the feed port of the gas-liquid separator.

8. The device according to claim 6, characterized in that The gas-liquid separator comprises a liquid phase discharge port and a gas phase discharge port; The liquid phase discharge port is connected to the distillation tower; The gas phase discharge port is communicated with the condensation separator.

9. The device according to claim 6, characterized in that The distillation tower includes a fractionation section and a rectification section from top to bottom; The fractionation section includes a gas phase condenser and a collector from top to bottom; The rectification section includes a distributor and a falling film heater from top to bottom; A feed inlet is arranged in the middle of the distillation tower, and the feed inlet is communicated with the liquid phase discharge port and the distributor respectively.

10. The device according to claim 6, characterized in that The short-path distiller is a short-path molecular distiller, and a rotary scraping mode structure is adopted inside the short-path molecular distiller.

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