阅读说明：本技术 一种低温催化改质沥青及其制备方法 (Low-temperature catalytic modified asphalt and preparation method thereof ) 是由 陈胜春 孙昱 雷兴红 万劲松 刘小敏 吴恒喜 吴术彬 雷红启 张启刚 李�诚 周 于 2020-05-29 设计创作，主要内容包括：本发明涉及一种低温催化改质沥青及其制备方法。其技术方案是：将100质量份的中温煤沥青置于带有蒸馏装置的反应釜内,在100～105℃和100～300rpm的条件下搅拌5～10min；再向所述反应釜中加入0.001～0.002质量份的无水三氯化铝,在280～300℃和150～200rpm的条件下搅拌150～200min；然后在280～300℃、100～150rpm和真空度为-0.09MPa的条件下蒸馏20～30min,减压蒸馏出轻质组分,制得低温催化改质沥青。本发明具有工艺简单、成本低、聚合反应温度低、能避免斧底结焦和延长反应釜使用寿命的特点,所制备的制品符合标准、产品质量稳定和性能好。(The invention relates to low-temperature catalytic modified asphalt and a preparation method thereof. The technical scheme is as follows: placing 100 parts by mass of medium-temperature coal pitch into a reaction kettle with a distillation device, and stirring for 5-10 min at 100-105 ℃ and 100-300 rpm; then adding 0.001-0.002 parts by mass of anhydrous aluminum trichloride into the reaction kettle, and stirring for 150-200 min at the temperature of 280-300 ℃ and at the rpm of 150-200; and then distilling for 20-30 min at 280-300 ℃ and 100-150 rpm under the vacuum degree of-0.09 MPa, and distilling out light components under reduced pressure to obtain the low-temperature catalytic modified asphalt. The invention has the characteristics of simple process, low cost, low polymerization temperature, capability of avoiding the coking of the kettle bottom and prolonging the service life of the reaction kettle, and the prepared product meets the standard and has stable product quality and good performance.)

1. A preparation method of low-temperature catalytic modified asphalt is characterized by comprising the following steps:

placing 100 parts by mass of medium-temperature coal pitch into a reaction kettle with a distillation device, heating to 100-105 ℃ at a heating rate of 5-10 ℃/min, and stirring at a rotating speed of 100-300 rpm for 5-10 min under a heat preservation condition; adding 0.001-0.002 parts by mass of anhydrous aluminum trichloride into the reaction kettle, heating to 280-300 ℃ at a heating rate of 10-15 ℃/min, and stirring at a rotating speed of 150-200 rpm for 150-200 min under a heat preservation condition; and then carrying out reduced pressure distillation for 20-30 min under the conditions that the temperature is 280-300 ℃, the rotating speed is 100-150 rpm and the vacuum degree is-0.09 MPa, distilling out light components, and preparing the low-temperature catalytic modified asphalt.

2. The method for preparing low-temperature catalytically upgraded asphalt according to claim 1, wherein the medium-temperature coal tar pitch: the softening point is 85 ℃; toluene insoluble matter is 20%; quinoline insoluble matter is 7%; the coking value is 45.6%; the ash content was 0.26%.

3. A low-temperature catalytically modified asphalt, which is characterized by being prepared by the preparation method of the low-temperature catalytically modified asphalt according to any one of claims 1-2.

Technical Field

The invention belongs to the technical field of modified asphalt. In particular to low-temperature catalytic modified asphalt and a preparation method thereof.

Technical Field

The modified asphalt is also called graphite electrode asphalt, electrode bonding asphalt and high-quality asphalt, and is widely used as an ultrahigh or high-power electrode for electric furnace steel making, anode paste for electrolytic aluminum and a binder for carbon products. As an ideal binder for carbon products, the modified asphalt has the characteristics of high Toluene Insoluble (TI), certain Quinoline Insoluble (QI), low volatile content, high beta resin content and the like, so the carbon products produced by using the modified asphalt as the binder have the advantages of low resistance, good conductivity, large capacitance density, low power consumption, high strength, long service life, small thermal expansion and the like. In recent years, with the adjustment of the structure of steel and aluminum products, the demand for high-power electrodes has increased, and the demand for modified asphalt has increased year by year.

The existing method for producing modified asphalt is mainly a high-temperature thermal polymerization method. Namely, at the high temperature of 380-400 ℃, polycyclic aromatic hydrocarbon generates free radicals to synthesize relatively macromolecular polymerized polycyclic aromatic hydrocarbon when heated, so that toluene insoluble substances and quinoline insoluble substances are increased, and the modified asphalt has certain cohesiveness and strength and reaches the standard of the modified asphalt. Compared with the oxidative thermal polymerization method and the vacuum flash evaporation method, the high-temperature thermal polymerization method has simple process and easy control of product quality. However, the production of modified asphalt by high-temperature thermal polymerization has the characteristics of high energy consumption, high pressure in a reactor, easy coking of the reactor, high equipment requirement and the like, and meanwhile, the asphalt is easy to be excessively crosslinked and polymerized at high temperature, and the part which is heated unevenly is slightly coked, so that the quality of the modified asphalt is unstable and even unqualified. Therefore, how to reduce the polymerization temperature of coal pitch, reduce pitch coking and prolong the service life of a reaction kettle becomes an urgent problem to be solved for energy conservation and emission reduction (ma advances the industry, measures for improving the coking of the modified pitch reaction kettle [ J ]. Fuel and chemical industry, 2008, 39(6): 51-52).

The technical personnel at home and abroad carry out extensive development and research work on the modified asphalt, such as 'modified asphalt and preparation method thereof' (CN201410021224.0, CN103756705A, CN103756707A) patent technology, and the modified asphalt is prepared by adding heavy oil and aldehyde crosslinking agent into high-temperature asphalt (115 ℃ -160 ℃), mixing under the catalysis of acid, and carrying out crosslinking polymerization; although the method can increase the content of the beta resin of the modified asphalt and enhance the caking property of the asphalt, the graphitizable degree of the modified asphalt is reduced to a certain extent, and the prepared carbon product has low conductivity and is not suitable for being used as a caking agent of a graphite electrode. For example, in the technology of the 'process for modifying asphalt by heating and flashing once and maintaining pressure' (CN104804758B), a tubular furnace is used for heating, and the problems of excessive crosslinking polymerization of asphalt components at high temperature, nonuniform heating, easy coking and the like are avoided through reduced pressure distillation, but the prepared modified asphalt has small condensation degree, and the content of beta resin, toluene insoluble substances and quinoline insoluble substances is lower than the corresponding content of the modified asphalt prepared by a thermal polymerization method.

In conclusion, the prior art can not produce qualified products of the ideal binder for carbon products, but also can avoid the problems of high reaction temperature, easy local coking and short service cycle of the reaction kettle.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and aims to provide a preparation method of low-temperature catalytic modified asphalt, which has simple process and low polymerization reaction temperature, avoids coking at the bottom of a kettle and prolongs the service cycle of a reaction kettle.

In order to realize the purpose, the invention adopts the technical scheme that:

placing 100 parts by mass of medium-temperature coal pitch into a reaction kettle with a distillation device, heating to 100-105 ℃ at a heating rate of 5-10 ℃/min, and stirring at a rotating speed of 100-300 rpm for 5-10 min under a heat preservation condition; adding 0.001-0.002 parts by mass of anhydrous aluminum trichloride into the reaction kettle, heating to 280-300 ℃ at a heating rate of 10-15 ℃/min, and stirring at a rotating speed of 150-200 rpm for 150-200 min under a heat preservation condition; and then carrying out reduced pressure distillation for 20-30 min under the conditions that the temperature is 280-300 ℃, the rotating speed is 100-150 rpm and the vacuum degree is-0.09 MPa, distilling out light components, and preparing the low-temperature catalytic modified asphalt.

The medium-temperature coal pitch: the softening point is 85 ℃; toluene insoluble matter is 20%; quinoline insoluble matter is 7%; the coking value is 45.6%; the ash content was 0.26%.

Due to the adoption of the technical scheme, compared with the prior art, the invention has the following advantages:

1. the invention adopts a free radical reaction mechanism that anhydrous aluminum trichloride catalyzes polycyclic aromatic hydrocarbon polymerization and is different from high-temperature thermal polymerization, the anhydrous aluminum trichloride and electron-rich polycyclic aromatic hydrocarbon generate polycyclic aromatic hydrocarbon cations, and the polycyclic aromatic hydrocarbon cations and another electron-rich polycyclic aromatic hydrocarbon undergo electrophilic addition so as to cause polymerization reaction. The cationic polymerization reaction has low activation energy, can promote the polymerization reaction to occur at a lower temperature, and has low energy consumption.

2. The medium-temperature coal pitch adopted by the invention has 20% of toluene insoluble substances per se, the standard of general modified pitch is 28-32%, the polymerization increase degree is low, the medium-temperature coal pitch can be catalyzed and polymerized to reach the standard of the modified pitch only by adding a very small amount of anhydrous aluminum trichloride Lewis acid catalyst, and the production process is simple; the ash content meets the requirement, the property of the modified asphalt is basically not influenced, and the product quality is stable and the performance is good.

3. The corrosion of the anhydrous aluminum trichloride on equipment is basically negligible, the coking at the bottom of the kettle can be avoided, the service cycle of the reaction kettle can be prolonged, and compared with a high-temperature polymerization process, the anhydrous aluminum trichloride has the advantages of less coking in the kettle, long service cycle of the reaction kettle, low production cost and high production efficiency;

4. the invention adjusts the quality (softening point, toluene insoluble substance, quinoline insoluble substance, coking value and ash content) of the modified asphalt by shortening or prolonging the reaction time, and has simple production and blending and easy operation.

Therefore, the invention has the characteristics of simple process, low cost, low polymerization reaction temperature, capability of avoiding the coking of the kettle bottom and prolonging the service cycle of the reaction kettle, and the prepared low-temperature catalytic modified asphalt meets the standard, has stable product quality and good performance, and is an ideal binder for carbon products.

Detailed Description

The invention is further described with reference to specific embodiments, without limiting its scope:

the medium temperature asphalt of the present embodiment: the softening point is 85 ℃; toluene insoluble matter is 20%; quinoline insoluble matter is 7%; the coking value is 45.6%; the ash content was 0.26%.