CN110294864B

CN110294864B - Asphalt VOC inhibitor based on FCC waste catalyst, smoke-suppressing asphalt and preparation method thereof

Info

Publication number: CN110294864B
Application number: CN201910309484.0A
Authority: CN
Inventors: 薛永杰; 胡振华; 王晨
Original assignee: Wuhan University of Technology WUT
Current assignee: Wuhan University of Technology WUT
Priority date: 2019-04-17
Filing date: 2019-04-17
Publication date: 2021-07-27
Anticipated expiration: 2039-04-17
Also published as: CN110294864A

Abstract

The invention relates to the technical field of inhibition of volatile organic compounds of asphalt, in particular to an asphalt VOC inhibitor, smoke-inhibiting asphalt and a preparation method thereof. The specific method for preparing the smoke-inhibiting asphalt comprises the following steps: firstly, screening the FCC spent catalyst with the size less than 0.075mm, taking the screened spent catalyst as an inhibitor, and drying; heating the matrix asphalt to 150-170 ℃ by using an electric furnace oil bath, stirring, adding the FCC waste catalyst into the matrix asphalt during stirring, and after stirring, putting the asphalt into a high-speed shearing stirrer for shearing to obtain the smoke-suppressing asphalt. The invention has the beneficial effects that: the waste FCC catalyst is applied to the asphalt VOC inhibitor, so that the problem of treatment of the waste FCC catalyst is solved, and the resource utilization of solid waste is realized; moreover, the porous molecular sieve structure on the surface of the FCC spent catalyst adsorbs small molecular substances in the asphalt, thereby inhibiting the release of VOC in the asphalt and reducing the environmental pollution.

Description

Asphalt VOC inhibitor based on FCC waste catalyst, smoke-suppressing asphalt and preparation method thereof

Technical Field

The invention relates to the technical field of inhibition of asphalt volatile organic compounds, in particular to an asphalt VOC inhibitor based on catalytic FCC waste catalyst, smoke-inhibiting asphalt and a preparation method thereof.

Background

The asphalt is a dark brown mixture composed of hydrocarbons with different molecular weights and derivatives thereof, and the component types of the asphalt are complex and various. During blending and spreading, asphalt can release Volatile Organic Compounds (VOC) in large quantities due to the high temperatures experienced. Research shows that the asphalt VOC mainly comprises hydrocarbon substances including halogenated hydrocarbon, oxygen-containing hydrocarbon, nitrogen hydrocarbon, sulfur hydrocarbon and polycyclic aromatic hydrocarbon with low boiling point, the substances have extremely small particles and great harm, once a human body inhales the substances, the health of the human body is greatly influenced, and meanwhile, the particles suspended in the air can also seriously pollute the natural environment after falling to the ground. In view of the potential great harm of asphalt VOC to human bodies and the environment, researchers at home and abroad make a great deal of research work on the aspect of VOC inhibition, and the method has important significance for reducing the release of asphalt VOC. At present, inhibitor modification methods are recognized as effective methods for inhibiting VOC release from the source, and can be divided into three main categories according to the inhibition principle: adsorbents, polymer modifiers, and flame retardants. The adsorbent provides larger surface area and molecular bond acting force by utilizing the porous structure of the adsorbent, and when the asphalt enters the porous structure, small molecular substances in the asphalt are absorbed and fixed by gaps, so that the asphalt becomes more stable, and the aim of inhibiting VOC (volatile organic compounds) release is fulfilled; the polymer modifier is used for forming a compact network structure in the asphalt through a polymer, so that small molecular substances are fixed in the network structure, and the release of VOC is reduced; the principle of the flame retardant is to cut off the relationship between asphalt and heat, thereby reducing the surface temperature of the asphalt and reducing the volatilization of light components. The asphalt VOC inhibitor has unobvious effect at the present stage, and has complex manufacturing process and higher cost.

Fluidized Catalytic Cracking (FCC) is a process of Cracking heavy oil into C1-C4 gas, gasoline, diesel oil and the like at 700-800 ℃, and is the most important secondary processing process of crude oil in the petroleum refining process. In this process, metal ions such as nickel (Ni), iron (Fe), and vanadium (V) contained in the feedstock oil are deposited on the FCC catalyst surface, resulting in catalyst poisoning and deactivation. The main component of the deactivated FCC catalyst (waste FCC catalyst) is SiO₂And A1₂O₃The porous molecular sieve has a porous molecular sieve structure, large specific surface area and pore volume and good adsorption performance. According to statistics, the usage amount of the FCC catalyst is large, which accounts for more than 86% of the usage amount of the catalyst in the petroleum refining industry, and about 35 million tons of FCC dead catalyst are generated globally every year. The waste FCC catalyst has high discharge amount, high heavy metal content, strong pollution and difficult treatment. The traditional landfill method can cause resource waste and also can cause serious pollution to soil, underground water and atmosphere, and a plurality of countries have made the prohibition on direct discharge of FCC waste catalyst, so that China also provides corresponding restriction measures for implementing the strategic goal of ecological culture and construction.

Disclosure of Invention

In view of the defects of the prior art, the invention aims to provide an asphalt VOC inhibitor based on FCC waste catalyst, smoke-suppressing asphalt and a preparation method thereof, and aims to reduce the release of asphalt VOC and achieve the aim of improving the environment.

The technical scheme adopted by the invention for solving the problems is as follows:

the asphalt VOC inhibitor is characterized in that the asphalt VOC inhibitor is a waste FCC catalyst, is taken from oil refineries of China petrochemical group, is powdery solid in appearance and free of agglomeration, and has Al as a main chemical component₂O₃And SiO₂Has porous molecular sieve structure, rough surface and density of 2.56g/cm³-2.85g/cm³The water content is 0.73-1.0%.

According to the scheme, the asphalt VOC inhibitor is characterized in that the proportion of micropores with the pore diameter of less than 5nm is 2.8%, the proportion of mesopores with the pore diameter of 5-50nm is 16.7%, and the proportion of macropores with the pore diameter of more than 50nm is 80.5%.

On the basis of the asphalt VOC inhibitor, the invention also provides smoke-inhibiting asphalt. The smoke-suppressing asphalt comprises the following components in parts by weight: 50 parts of matrix asphalt and 40-60 parts of FCC spent catalyst. The preparation method of the smoke-inhibiting asphalt comprises the following specific steps:

1) sieving FCC waste catalyst to control the particle size below 0.075 mm;

2) placing the screened FCC spent catalyst into a drying oven with the temperature of 100-;

3) in order to prevent the asphalt from being heated unevenly and aged, heating the matrix asphalt to 150-170 ℃ by using an electric furnace oil bath, preserving heat and stirring, and adding the FCC waste catalyst obtained in the step 2) into the mixture for several times according to the proportion in the stirring process to mix uniformly;

4) putting the asphalt in the step 3) into a high-speed shearing machine for shearing, and heating the asphalt to 150-170 ℃ by adopting an electric furnace oil bath in the shearing process; and after the shearing is finished, obtaining the smoke-inhibiting asphalt.

According to the scheme, the matrix asphalt adopts No. 70 matrix asphalt, the penetration degree (25 ℃, 100g and 5s) is 68(0.1mm), the softening point (ring and ball method) is 48 ℃, the ductility (5cm/min and 15 ℃) is more than 100cm, the Brookfield viscosity (135 ℃) is 0.32Pa.s, and the density (15 ℃) is 1.035g/cm³The flash point was 413 ℃ and the solubility (trichloroethylene) was 99.7%.

According to the scheme, the FCC dead catalyst in the step 3) is added in 8-10 times, and the adding amount of each time is about 10% -12% of the total amount.

According to the scheme, in the step 3), the stirring speed is 300-350r/min, and the stirring time is 20-30 min.

According to the scheme, in the step 4), the shearing rate is 3000-4000r/min, and the shearing time is 0.5-1 h.

Compared with the prior art, the invention has the beneficial effects that:

the effect of the asphalt VOC inhibitor is not obvious at the present stage, the manufacturing process is complex, and the cost is high; the method uses the FCC waste catalyst with the particle size of less than 0.075mm for preparing the smoke-suppressing asphalt, not only solves the problem of treatment of the FCC waste catalyst, realizes resource utilization of solid wastes, but also well utilizes the porous molecular sieve structure of the FCC waste catalyst to adsorb small molecular substances of the asphalt, thereby inhibiting the formation of asphalt VOC and reducing environmental pollution.

Detailed Description

In order to better understand the present invention, the following examples are further provided to illustrate the content of the present invention, but the present invention is not limited to the following examples.

In the following examples, the spent FCC catalyst was obtained from refineries of China petrochemical group, and was in the form of powdery solid without agglomeration, and the main chemical component was Al₂O₃And SiO₂Has a porous molecular sieve structure (the ratio of micropores with a pore diameter of less than 5nm is 2.8%, the ratio of mesopores with a pore diameter of 5-50nm is 16.7%, the ratio of macropores with a pore diameter of more than 50nm is 80.5%), has rough surface and density of 2.56g/cm³The water content was 0.73%. Before sieving, the primary particle size distribution was as follows: the ratio of the particle size of less than 0.6mm is 100%, the ratio of the particle size of less than 0.15mm is 97.5%, and the ratio of the particle size of less than 0.075mm is 76.3%.

In the following examples, the base asphalt used was No. 70 base asphalt, which had a penetration (25 ℃, 100g, 5s) of 68(0.1mm), a softening point (ring and ball method) of 48 ℃, an elongation (5cm/min, 15 ℃) of > 100cm, a Brookfield viscosity (135 ℃) of 0.32Pa.s, and a density (15 ℃) of 1.035g/cm³The flash point was 413 ℃ and the solubility (trichloroethylene) was 99.7%.

Examples

The embodiment adopts FCC waste catalyst as asphalt VOC inhibitor, and provides a smoke-inhibiting asphalt which comprises the following raw materials in parts by weight: 50 parts of No. 70 matrix asphalt and 50 parts of FCC spent catalyst.

The preparation method of the smoke-inhibiting asphalt comprises the following specific steps:

1) firstly, screening the FCC spent catalyst, wherein the particle size is controlled to be below 0.075 mm;

2) putting the screened FCC spent catalyst into a 105 ℃ oven for heating for 4 hours, and drying moisture;

3) heating 50 parts of No. 70 matrix asphalt to 160 ℃ by using an electric furnace oil bath, preserving heat and stirring, and adding 50 parts of FCC spent catalyst obtained in the step 2) into the mixture by 10 times in the stirring process, wherein the adding amount of each time is about 10 percent of the total amount; wherein the stirring speed is 325r/min, and the stirring time is 25 min;

4) putting the asphalt in the step 3) into a high-speed shearing machine for shearing, wherein the shearing rate is 3500r/min, the shearing time is 45min, and the asphalt is heated to 160 ℃ by adopting an electric furnace oil bath in the shearing process and is kept warm; and after the shearing is finished, obtaining the smoke-inhibiting asphalt.

The VOC components of the smoke-suppressing asphalt obtained in the embodiment are qualitatively and quantitatively analyzed and characterized by a gas chromatography-mass spectrometer (GC-MS). And (3) respectively putting the No. 70 matrix asphalt and the smoke-suppressing asphalt obtained in the embodiment into a thermal cracking device for heating, setting the initial temperature to be 50 ℃, the heating rate to be 10 ℃/S, the maximum temperature to be 200 ℃, keeping the temperature for 35min, and selecting a full-scanning mode by a mass spectrometer for test analysis. Considering the reason that the VOC components of asphalt are complicated and various and have different contents, it is very difficult to evaluate the inhibitory effect of the spent FCC catalyst on a single substance, and thus the inhibitory effect of the spent FCC catalyst is evaluated by dividing the VOC components of asphalt into chain hydrocarbons, hydrocarbon derivatives and polycyclic aromatic hydrocarbons. The test results are shown in table 1, table 2 and table 3.

TABLE 1 comparison of VOC chain hydrocarbon components of different bitumens

TABLE 2 comparison of VOC hydrocarbon derivative components of different bitumens

TABLE 3 comparison of VOC polycyclic aromatic hydrocarbon components for different bitumens

As can be seen from tables 1-3: the No. 70 matrix asphalt has complex VOC components, high content of chain hydrocarbon substances and various types, and then hydrocarbon derivatives and polycyclic aromatic hydrocarbon substances; the emission of VOC of the smoke-inhibiting asphalt obtained in the embodiment is obviously reduced, and the inhibition rates of the smoke-inhibiting asphalt on chain hydrocarbon, hydrocarbon derivatives and polycyclic aromatic hydrocarbon substances reach 56%, 67.9% and 54.6% respectively, which shows that the FCC waste catalyst plays a good role in inhibiting the VOC of the asphalt.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, many modifications and changes can be made without departing from the inventive concept of the present invention, and these modifications and changes are within the protection scope of the present invention.

Claims

1. The preparation method of the smoke-inhibiting asphalt is characterized by comprising the following specific steps:

1) sieving FCC waste catalyst to control the particle size below 0.075 mm; wherein the pore size distribution of the FCC spent catalyst is as follows: the proportion of micropores with the pore diameter of less than 5nm is 2.8 percent, the proportion of mesopores with the pore diameter of 5-50nm is 16.7 percent, and the proportion of macropores with the pore diameter of more than 50nm is 80.5 percent;

2) placing the screened FCC spent catalyst into a drying oven with the temperature of 100-110 ℃, heating for 3-5h, and drying moisture;

3) heating the matrix asphalt to 160-170 ℃, preserving heat and stirring, adding the FCC spent catalyst obtained in the step 2) for 8-10 times according to the proportion in the stirring process, wherein the adding amount of each time is equal to 10-12 percent of the total amount of the FCC spent catalyst, and uniformly mixing; wherein, calculated by weight portion, 50 portions of matrix asphalt and 40 to 60 portions of FCC spent catalyst; the stirring speed is 300-350r/min, and the stirring time is 20-30 min;

4) putting the asphalt obtained in the step 3) into a shearing machine for shearing, and keeping the temperature at 160-170 ℃ in the shearing process; after the shearing is finished, obtaining smoke-suppressing asphalt; wherein the shearing rate is 3000-4000r/min, and the shearing time is 0.5-1 h;

the FCC spent catalyst has a porous molecular sieve structure, a rough surface and a density of 2.56g/cm³-2.85 g/cm³The water content is 0.73-1.0%.

2. The method according to claim 1, wherein the matrix asphalt is No. 70 matrix asphalt, the penetration measured at 25 ℃ is 68, the softening point is 48 ℃, the ductility measured at 15 ℃ and 5cm/min is more than 100cm, the Brookfield viscosity measured at 135 ℃ is 0.32Pa.s, and the density measured at 15 ℃ is 1.035g/cm³The flash point is 413 ℃, and the solubility is 99.7 percent by taking trichloroethylene as a solvent.