CN101279889B - Production method of high-chlorinity chlorinated alkane - Google Patents
Production method of high-chlorinity chlorinated alkane Download PDFInfo
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- CN101279889B CN101279889B CN2008101236209A CN200810123620A CN101279889B CN 101279889 B CN101279889 B CN 101279889B CN 2008101236209 A CN2008101236209 A CN 2008101236209A CN 200810123620 A CN200810123620 A CN 200810123620A CN 101279889 B CN101279889 B CN 101279889B
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Abstract
The invention discloses a production process for high chlorine content chlorinated alkane, which uses the bulk modification method to promote the chlorination reaction between the solid high carbon normal alkane, liquid high carbon normal alkane and a chlorine liquid or a preheated chlorine gas under the action of a complex initiation system, the reaction includes ten phases, a chlorine-water mixture is supplied to implement the bulk modification action at the mid- and post-phase of the reaction, so the problems of difficult heat transfer and mass transfer of the reaction system are solved, the reaction temperature is between 40 and 200 DEG C, the time of each phase is controlled strictly, therefore the high chlorine content chlorinated alkane product is synthesized ultimately, the chlorine content of the product is up to 70 to 74 percent, and organic solvents such as carbon tetrachloride are not contained.
Description
Technical field
The present invention relates to a kind of method for manufacturing of solid chloralkane, relate in particular to a kind of method that adopts composite initiation system, environment-protective process to produce high-chlorinity chlorinated alkane.
Background technology
The high-chlorinity chlorinated alkane product is good, the cheap additive flame retardant of flame retardant properties, and outward appearance is white or faint yellow solid powder or particulate product normally.This product use is very extensive, can be used as multiple plastics, rubber, and the fire retardant of product of rubber and plastic and coating also can be used as oil dope, the properties-correcting agent of papermaking and printing ink.The product that can make has fire retarding conveying band, fire-resistant cable material, frie retardant coating, glass fiber reinforced plastics product, fire-resistant engineering plastics etc., also can be used as fire-proof additive, the properties-correcting agent of paper industry and the surface treatment agent of fabric of printing ink.
Know that by fire retardant mechanism the flame retardant properties quality of chloralkane depends on the height of cl content.In general, the cl content of product is high more, and flame retardant properties is good more, so, if improve the cl content of product, will directly promote the flame retardant properties of fire-retardant product, the flame retarding efficiency of product is obviously promoted; Improving the product leading indicator---in the cl content, must coordinate the mutual relationship of color and luster, softening temperature and the heat stability index of chloralkane product, only accomplish coordinated with each otherly, could obtain the product of being satisfied with.
The production technique of producing high-chlorinity chlorinated alkane mainly contains at present: solvent method, water phase suspension, substance law etc.Solvent method promptly adopts organic solvent, mainly is the production technique that carbon tetrachloride solvent is produced clorafin as medium, and this technological development is with a long history, the production technology maturation, but, bring pollution to environment easily because of the environmental protection defective, eliminated by market gradually; The water method is to use maximum production technique, but this method manufacturing technique requirent is higher, and the cl content of product is generally at 68-72%, and equipment corrosion is serious, equipment cost is high, produce the problem that often is corroded and interrupt, in addition, the purity of by-product acid and concentration are difficult to improve, the highlyest only can reach about 20%, and the industrial utilization of lower concentration by-product acid is worth not quite, often is used as the three wastes and handles, and brings serious pollution to environment easily; Substance law also is traditional production technique; production process is fairly simple; not not with an organic solvent; help environment protection, production cost is low, and plant factor is higher; but the production cycle is long; and along with the increase of system viscosity, the heat and mass of reaction system is difficulty very, and quality product can not effectively guarantee.Though above production method technology is different, the product quality problem that occurs has many identical,, many deficiencies such as product color poor, heat decomposition temperature low, softening temperature not high, long reaction time low as cl content.To sum up, existing production technique all has different limitation, produces the target that the high-chlorinity chlorinated alkane product is common pursuit of the same trade so seek suitable production technique.
Summary of the invention
At the existing deficiency of existing producing and manufacturing technique, technical problem to be solved by this invention provides a kind of production method of high-chlorinity chlorinated alkane, and this production method will solve not only that reaction late phase reaction material heat is difficult to transmit in the existing art production process, reaction mass is difficult to effectively flow, solve in the existing production technique the low deficiency of cl content in the product; And to solve in the existing production technique by-product hydrochloric acid concentration low, can't effectively utilize, thereby bring environmental pollution problems.
The production method of high-chlorinity chlorinated alkane of the present invention comprises the steps:
(A) in container initiator is mixed with normal paraffin, temperature is controlled at 20～60 ℃, gets composite initiator after 10～60 minutes through stirring homogenizing;
(B) dropping into 1～4 kind of carbon chain lengths in reactor is 13～41 normal paraffin or prechlorination thing, and temperature is controlled at 30～70 ℃, 10～60 minutes time, stirs;
(C) with in liquid chlorine or the chlorine feeding reactor through preheating, carry out Photoinitiated reactions, temperature is controlled at 50～80 ℃, reacts this step control work in-process cl content 10～42% 3～15 hours;
(D) drop into the composite initiator that is equivalent to normal paraffin quality 0.02%～0.025%, continue to feed the chlorine of liquid chlorine or process vaporizer gasification preheating, controlled temperature to 70～150 ℃, in 5～25 hours reaction times, this step control work in-process cl content is 20～52%;
(E) drop into the composite initiator that is equivalent to normal paraffin quality 0.02%～0.025% again, simultaneously the chlorine water mixture is fed in the reactor, controlled temperature to 90～180 ℃, the reaction times was controlled at 1～6 hour, and this step control work in-process cl content is 30～60%;
(F) add the emulsifying dispersant that is equivalent to normal paraffin quality 0.1～2%, input is equivalent to the composite initiator of normal paraffin quality 0.05～0.06%, then the chlorine water mixture is fed in the reactor, controlled temperature is at 100～200 ℃, and reactor pressure is controlled at 0～0.2MPa, 3～15 hours reaction times, this stage control cl content is 70～74%, through leaving standstill 0.5～3 hour, isolate the high-chlorinity chlorinated alkane crude product, all the other enter waste liquid, the tail gas absorption system is handled;
(G) device for absorbing tail gas of tail gas residual in the high-chlorinity chlorinated alkane crude product through graphite condenser and film-falling absorption tower composition absorbed, after cooling, enter hydrochloric acid tank and store;
(H) with the high-chlorinity chlorinated alkane crude product behind crystallisation by cooling, enter pulverizer and pulverize, and then enter the oven dry of vacuum drying equipment, 30～90 ℃ of bake out temperatures, drying time 20～60 minutes;
(I) the high-chlorinity chlorinated alkane crude product input after will drying is equivalent to anti-anti-prodegradant, organic tin stablizer or the rare-earth stabilizer be stained with of high-chlorinity chlorinated alkane crude product quality 0.1～2%, mixes in mixing machine 10～60 minutes;
(J) with mixed material, behind vibratory screening apparatus classification product, promptly obtain the high-chlorinity chlorinated alkane finished product, metering packing, and by the standard stacking.
The production method of a kind of high-chlorinity chlorinated alkane of the present invention has adopted modification substance law, the non-solvent method production technique of non-traditional meaning, uses composite initiation system that reaction system is carried out catalysis, compared with prior art, remarkable advantages is arranged:
A. owing to added environment-friendly type circulation heat and mass in production process, promptly the chlorine water mixture has solved the system viscosity height in reaction later stage, the problem that does not readily conduct heat fully.The chlorine water mixture can directly be removed heat of reaction fast, raising along with temperature, can take away lot of energy after the water vapor in the reaction system, steam after the vaporization comes back to the cooling of participating in material in the reactor after condensation, while is because of the participation of water, mass transfer is become easily, and the hydrogenchloride of generation is dissolved into hydrochloric acid very soon, can normal pressure or compressive reaction.Owing to added the chlorine water mixture in the reactor, solved reaction later stage system viscosity height fully, be difficult for the problem of mass-and heat-transfer, make the heat of the material in the reaction system obtain timely and effective discharging, viscosity is reduced greatly, makes reaction smooth.
B. in entire reaction course, do not use organic solvents such as tetracol phenixin, the pollution of organic solvents such as tetracol phenixin can not take place in process of production, can not bring organic solvent residue such as tetracol phenixin yet to the finished product.
C. owing to used the chlorine water mixture, make by-product hydrochloric acid concentration height, concentration can reach more than 31% or 31%, can be used as the certified products technical hydrochloric acid and uses, and good use value is arranged, and no discharging of waste liquid can not produce environmental pollution.
D. chlorine is utilized by 100% among the present invention, and non-exhaust emission can not produce environmental pollution.
E. the energy in this production method obtains fully, recycles, and it is minimum that energy consumption reaches, and the production cycle obviously shortens, the plant factor height, and corrodibility reduces, and production cost significantly reduces.
F. the product produced of this production method, quality index has remarkable advantages, and cl content is improved, and product color is significantly improved, organic solvent residuals such as no tetracol phenixin.The product performance of this production method manufacturing are superior, steady quality, and the main products technology quality index can reach: cl content 72 ± 2%, heat stability index＜0.2%, weight loss on heating＜0.5%, organic solvent residuals such as no tetracol phenixin.
Described composite initiator is the mixture of superoxide and azo compound, adopt the processing that is uniformly dispersed of the normal paraffin of carbon chain lengths 16～25, help composite initiator is disperseed, when helping feeding intake simultaneously, initiator and reactant are compatible, dispersion effect is strengthened greatly, improved the homogeneity of reaction.
Described normal paraffin is single or the mixing normal paraffin, also can adopt the single thing of normal paraffin or the mixture of prechlorination, and this significantly enlarges the scope of selecting for use of raw material, and the chloralkane that helps not reaching index fully utilizes, and the percentage of A-class goods is promoted.
Feed the cooling liqs or the normal temperature water coolant of circularly cooling in the described cooling duct, circularly cooling liquid can contain the aqueous solution of salt, ethylene glycol or other refrigeration agents, the circulating cooling liquid temperature controls to-40～20 ℃, chilled liquid temperature is low, help the rapid transfer of heat, help the raising of speed of response.
Described chlorine water mixture is meant liquid chlorine or liquid chlorine after vaporizer is heated to 0～50 ℃, with the hydrochloric acid mixture of process water or 0～30%.Liquid chlorine and process water or hydrochloric acid can be fed together by same pipeline, also can be entered in the reactor respectively by two pipelines respectively.The chlorine water mixture can directly be removed a large amount of reaction heat fast, raising along with temperature, water vapor in the reactor, can also take away lot of energy, water after the vaporization or sour water are back to the cooling of participating in material in the reactor again after condenser condenses, guarantee that material is not overheated, while being participated in directly because of water medium, the mass transfer of material is become easily, and the hydrogenchloride of generation is dissolved into hydrochloric acid very soon, can normal pressure or compressive reaction.
Granularity after described high chlorine contents chloralkane crude product is pulverized is controlled at about 0.1～3mm, helps oven dry fully.
Described mixing equipment has chuck outward, so that feed heat-eliminating medium cooling material, in the described used mixing machine spiral coil cooling tube is arranged, and wherein can feed heat-eliminating medium; In order to avoid material is softening or reassemble in mixing, helps metering, packing simultaneously and store.
Embodiment
In the following embodiments, the material of the below standard accurate granularity after the vibratory screening apparatus classification will reenter and pulverize and baking operation; It is anti-that to be stained with anti-prodegradant be kaolin or the water-ground limestone or the mixture of light calcium carbonate and rare-earth stabilizer.
Embodiment 1:
1000g BPO and 2000g AIBN are dissolved in the whiteruss of 3L, make composite initiator after stirring, standby;
In three placed in-line reactors, respectively drop into solid paraffin, the 20kg carbon chain lengths 17-22 of 280kg carbon chain lengths 20-30 whiteruss, be warming up to 60 ℃, treat the material fusion after, stirred 30 minutes; Open light-initiated system, feed chlorine through the vaporizer preheating, control feeding speed, is furnished with cooling duct in the reactor, feed the cooling liqs of circularly cooling in the pipeline, guarantee that the reaction heat in the material can effectively be derived, open the reactor jacket cooling system, assist the controlling reactor temperature at 75 ± 2 ℃, 10 hours reaction times; Drop into the 625g composite initiator, continue to feed chlorine, the logical chlorine speed of control makes temperature of reactor maintain 80～84 ℃, 5 hours reaction times; Throw the 625g composite initiator again, regulate logical chlorine speed, the controlling reactor temperature is at 90～94 ℃, 3 hours reaction times; Throw the 1250g composite initiator, drop into Arlacel-60 and each 500g of Tween-60, stirred 30 minutes, evenly after, feeding chlorine water mixture, the controlling reactor temperature is at 102～106 ℃, reactor pressure is controlled at 0.10～0.12MPa, 3 hours reaction times; Entire reaction stage accumulative total feeds chlorine 1650kg, and " throw the 625g composite initiator, regulate logical chlorine speed, the controlling reactor temperature is at 90～94 ℃, 3 hours reaction times above-mentioned; Drop into the 1250g composite initiator, drop into Arlacel-60 and each 500g of Tween-60, stirred 30 minutes, evenly, feed the chlorine water mixture, the controlling reactor temperature is at 102～106 ℃, reactor pressure is controlled at 0.10～0.12MPa, 3 hours reaction times " this two step of reaction accumulative total feed process water 1200kg; cl content is 70～74% after tested, has obtained clorafin-72 crude product, hydrogenchloride and chlorine gas that reaction produces; generate 31% by-product hydrochloric acid and 10～12% chlorine bleach liquores through absorbing; clorafin-72 crude product is pressed into crystallisation by cooling in the crystallization kettle under flow state, crystallisate is crushed to below the 0.2mm, drops in the vacuum drying machine; temperature is controlled at 60～65 ℃; drying time 60 minutes, add the 1kg rare-earth stabilizer and mix at mixing machine, cross 40 eye mesh screens after, promptly get clorafin-72 finished product 896kg, metering, packing, warehouse-in.
Embodiment 2:
600g BPO and 2400g AIBN are dissolved in the whiteruss of 3L, make composite initiator after stirring, standby;
In three placed in-line reactors, respectively throw the solid SEMI-REFINED PARAFFIN WAX of 300kg carbon chain lengths 20～30, heat up 60 ℃, treat the material fusion after, stirred 30 minutes; Open light-initiated system, slowly feed the chlorine through the vaporizer thermal pretreatment, control feeding speed makes the still temperature control at 77 ± 1 ℃, 12 hours reaction times, open cooling system, and assist control reaction temperature; Drop into the 500g composite initiator, continue to feed chlorine, the logical chlorine speed of control makes reactor temperature maintain 82～86 ℃, 6 hours reaction times; Drop into the 500g composite initiator again, regulate logical chlorine speed, in the controlling reactor temperature at 90～94 ℃, 3.5 hours reaction times; Drop into the 1500g composite initiator, drop into Arlacel-60 and each 500g of Tween-60, stirred 30 minutes, evenly after, feeding chlorine water mixture, the controlling reactor temperature is at 100～104 ℃, reactor pressure 0.10～0.12MPa, 2.5 hours reaction times; Full response stage accumulative total feeds chlorine 1670kg, above-mentioned " drop into the 500g composite initiator, regulate logical chlorine speed, in the controlling reactor temperature at 90～94 ℃, 3.5 hours reaction times; Drop into the 1500g composite initiator, drop into Arlacel-60 and each 500g of Tween-60, stirred 30 minutes, evenly, feed the chlorine water mixture, the controlling reactor temperature is at 100～104 ℃, reactor pressure 0.10～0.12MPa, 2.5 hours reaction times " this two step of reaction accumulative total feed process water 1180kg; cl content is 70～74% after tested, has obtained clorafin-72 crude product, hydrogenchloride and chlorine gas that reaction produces; generate 31% by-product hydrochloric acid and 10-12% chlorine bleach liquor through absorbing; clorafin-72 crude product is pressed into crystallisation by cooling in the crystallization kettle under flow state, crystallisate is crushed to below the 0.2mm, drops in the vacuum drying machine; temperature is controlled at 60～65 ℃; drying time 60 minutes, add the 1kg rare-earth stabilizer and mix at mixing machine, cross 40 eye mesh screens after, promptly get clorafin-72 finished product 908kg, metering, packing, warehouse-in.
Claims (9)
1. the production method of a high-chlorinity chlorinated alkane is characterized in that this production method comprises the steps:
(A) in container BPO and AIBN are mixed with whiteruss, temperature is controlled at 20～60 ℃, gets composite initiator after 10～60 minutes through stirring homogenizing;
(B) dropping into 1～4 kind of carbon chain lengths in reactor is 13～41 normal paraffin, and temperature is controlled at 30～70 ℃, 10～60 minutes time, stirs;
(C) with in liquid chlorine or the chlorine feeding reactor through preheating, carry out Photoinitiated reactions, temperature is controlled at 50～80 ℃, reacts this step control work in-process cl content 10～42% 3～15 hours;
(D) drop into the composite initiator that is equivalent to normal paraffin quality 0.02%～0.025%, continue to feed the chlorine of liquid chlorine or process vaporizer gasification preheating, controlled temperature to 70～150 ℃, in 5～25 hours reaction times, this step control work in-process cl content is 20～52%;
(E) drop into the composite initiator that is equivalent to normal paraffin quality 0.02%～0.025% again, simultaneously the chlorine water mixture is fed in the reactor, controlled temperature to 90～180 ℃, the reaction times was controlled at 1～6 hour, and this step control work in-process cl content is 30～60%;
(F) add the emulsifying dispersant that is equivalent to normal paraffin quality 0.1～2%, input is equivalent to the composite initiator of normal paraffin quality 0.05～0.06%, then the chlorine water mixture is fed in the reactor, controlled temperature is at 100～200 ℃, and reactor pressure is controlled at 0～0.2MPa, 3～15 hours reaction times, this stage control cl content is 70～74%, through leaving standstill 0.5～3 hour, isolate the high-chlorinity chlorinated alkane crude product, all the other enter waste liquid, the tail gas absorption system is handled;
(G) device for absorbing tail gas of tail gas residual in the high-chlorinity chlorinated alkane crude product through graphite condenser and film-falling absorption tower composition absorbed, after cooling, enter hydrochloric acid tank and store;
(H) with the high-chlorinity chlorinated alkane crude product behind crystallisation by cooling, enter pulverizer and pulverize, and then enter the oven dry of vacuum drying equipment, 30～90 ℃ of bake out temperatures, drying time 20～60 minutes;
(I) the high-chlorinity chlorinated alkane crude product input after will drying is equivalent to anti-anti-prodegradant, organic tin stablizer or the rare-earth stabilizer be stained with of high-chlorinity chlorinated alkane crude product quality 0.1～2%, mixes in mixing machine 10～60 minutes;
(J) with mixed material, behind vibratory screening apparatus classification product, promptly obtain the high-chlorinity chlorinated alkane finished product, metering packing, and by the standard stacking.
2. by the production method of the described high-chlorinity chlorinated alkane of claim 1, it is characterized in that described normal paraffin is single or mixes normal paraffin, or the single thing of normal paraffin or the mixture of prechlorination.
3. press the production method of the described high-chlorinity chlorinated alkane of claim 1, the method that it is characterized in that described controlled temperature is cooling liqs or the normal temperature water coolant that feeds circularly cooling in the reaction cooling duct, circularly cooling liquid can contain a certain amount of salt, ethylene glycol or other refrigeration agents, and temperature remains on-40～20 ℃.
4. by the production method of the described high-chlorinity chlorinated alkane of claim 1, it is characterized in that described chlorine water mixture be liquid chlorine or liquid chlorine after vaporizer is heated to assigned temperature, with process water or with 0～30% hydrochloric acid mixture.
5. by the production method of the described high-chlorinity chlorinated alkane of claim 1, it is characterized in that the granularity after described high-chlorinity chlorinated alkane crude product is pulverized is controlled at about 0.1～3mm.
6. by the production method of the described high-chlorinity chlorinated alkane of claim 1, it is characterized in that described used mixing machine has outer chuck so that feed heat-eliminating medium cooling material, in spiral coil cooling tube is arranged, wherein can feed heat-eliminating medium.
7. by the production method of the described high-chlorinity chlorinated alkane of claim 1, it is characterized in that the material of the below standard accurate granularity after the described vibratory screening apparatus classification, will reenter and pulverize and baking operation.
8. by the production method of the described high-chlorinity chlorinated alkane of claim 1, it is characterized in that described anti-to be stained with anti-prodegradant be kaolin or water-ground limestone.
9. by the production method of the described high-chlorinity chlorinated alkane of claim 1, it is characterized in that the described anti-mixture that anti-prodegradant is light calcium carbonate and rare-earth stabilizer of being stained with.
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