At present, the chemical utilization of C4 fraction in China is still in its infancy. Most C4 fractions in the refinery directly enter the alkylation unit to produce alkylated gasoline or superimposed gasoline; Part of it is used to produce lubricating oil additives polybutene and polyisobutylene; In addition, methyl tert-butyl ether is produced from isobutylene; A small amount of isobutylene is used to produce alkylphenol and n-butene is used to produce sec-butanol. It can be seen that the application of C4 fraction will have a great development prospect in China in the future. At present, the research work in this field has been carried out and achieved certain results.
1 application of fuel
A large number of C4 hydrocarbons in the world are mainly used as fuels. Taking butene as an example, about 90% is used as fuel, and only 65,438+00% is used in the chemical market. Compared with directly using C4 hydrocarbons as fuel, processing C4 hydrocarbons into various liquid fuels or additives such as alkylated oil, methyl tert-butyl ether and liquefied petroleum gas for vehicles has high application value.
Methyl tert-butyl ether (MTBE) produced from C4 hydrocarbons, as a gasoline blending component and octane number improver, is one of the few petrochemical products in the world that have developed rapidly. However, due to the pollution of methyl tert-butyl ether to drinking water, methyl tert-butyl ether has been restricted or banned in some parts of the United States since June 5438+1October 2004. The global production capacity and demand of methyl tert-butyl ether showed an obvious downward trend. In contrast, the development of alkylated oil is an important way to utilize C4 hydrocarbon fuel. In 2003, the global alkylation capacity reached 82 12Mt, which was 5.4% higher than that of 200 1. Solid acid alkylation technology has been widely concerned because of its obvious advantages in environmental protection and safety, which represents the development direction of alkylation technology. At present, many patent companies in the world are developing solid paraffin activation processes, some of which have completed pilot tests. The indirect alkylation process developed in recent years is generally favored by the petroleum and petrochemical industry because of its wider range of raw materials and lower production cost.
In a word, producing C4 fuel products with high added value and developing and applying new technologies for C4 fuel utilization are the general trend of developing C4 fuel utilization abroad and the inevitable choice of China petroleum and petrochemical industry.
3 Conclusion
In recent years, due to the rapid development of natural gas industry, the consumption of mixed C4 as traditional civil liquefied gas will gradually decrease. Therefore, we should comprehensively analyze the market of C4 downstream products, and don't blindly pursue chemical utilization. Secondly, broadening the use of butadiene and butene is the key technology to develop the comprehensive utilization of C4 hydrocarbons. Such as self-disproportionation of ethylene and 2- butene to increase propylene production, catalytic cracking of C4/C5 hydrocarbons to produce propylene and ethylene, automatic disproportionation of C4 hydrocarbons, oligomerization of butene, hydrogenation to produce alkyl oil, solid alkylation and other technologies, which provide strong technical support for the comprehensive utilization of C4 hydrocarbons. Due to the increasing demand for high-octane gasoline blending raw materials, the utilization of high-value fuel is still the most important way to apply C4 hydrocarbons for a long time.
Question 2: Introduction to 2:C4: Colorless combustible gas. Melting point? 138.432 c, boiling point? 0.522°C, liquid density 600 g/l (0 c, 1 ATM), refractive index1.3326 (20 c), critical temperature152.0 c, critical pressure 3796.0 kPa and critical volume 255mL/mol. Insoluble in water, soluble in hydrocarbons such as ethanol, ether and chloroform. It forms an explosive mixture with air, and the explosion limit is 19%~84% (at night). Colorless gas with slight bad smell. Main uses: used in organic synthesis and ethylene production, instrument calibration, and also used as fuel.
Question 3: What is the specific difference between mild C4 and severe C4? Mixed C4 is an important petrochemical resource, which is the general name of alkanes, monoolefins and dienes. C4 in refinery is mainly composed of n-butene, isobutylene, n-butane, isobutane and butadiene. The most valuable components in chemical industry are n-butene, isobutylene and butadiene, followed by n-butane. At present, the chemical utilization of C4 fraction in China is still in its infancy. Most C4 fractions in the refinery directly enter the alkylation unit to produce alkylated gasoline or superimposed gasoline; Part of it is used to produce lubricating oil additives polybutene and polyisobutylene; In addition, methyl tert-butyl ether is produced from isobutylene; A small amount of isobutylene is used to produce alkylphenol and n-butene is used to produce sec-butanol. It can be seen that the application of C4 fraction will have a great development prospect in China in the future. At present, the research work in this field has been done and some achievements have been made. 1 Fuel application A large number of C4 hydrocarbons in the world are mainly used as fuels. For example, about 90% of butene is used as fuel, and only 10% is used in the chemical market. Compared with directly using C4 hydrocarbons as fuel, processing C4 hydrocarbons into various liquid fuels or additives such as alkylated oil, methyl tert-butyl ether and liquefied petroleum gas for vehicles has high application value. Methyl tert-butyl ether (MTBE) produced from C4 hydrocarbons, as a gasoline blending component and octane number improver, is one of the few petrochemical products in the world that have developed rapidly. However, due to the pollution of methyl tert-butyl ether to drinking water, methyl tert-butyl ether has been restricted or banned in some parts of the United States since June 5438+1October 2004. The global production capacity and demand of methyl tert-butyl ether showed an obvious downward trend. In contrast, the development of alkylated oil is an important way to utilize C4 hydrocarbon fuel. In 2003, the global alkylation capacity reached 82 12Mt, which was 5.4% higher than that of 200 1. Solid acid alkylation technology has been widely concerned because of its obvious advantages in environmental protection and safety, which represents the development direction of alkylation technology. At present, many patent companies in the world are developing solid alkylation processes, some of which have completed pilot tests. The indirect alkylation process developed in recent years is generally favored by the petroleum and petrochemical industry because of its wider range of raw materials and lower production cost. In a word, producing C4 fuel products with high added value and developing and applying new technologies for C4 fuel utilization are the general trend of developing C4 fuel utilization abroad and the inevitable choice of China petroleum and petrochemical industry. Conclusion Due to the rapid development of natural gas industry in recent years, the consumption of mixed C4 as traditional civil liquefied gas will gradually decrease. Therefore, we should comprehensively analyze the market of C4 downstream products, and don't blindly pursue chemical utilization. Secondly, broadening the use of butadiene and butene is the key technology to develop the comprehensive utilization of C4 hydrocarbons. Such as self-disproportionation of ethylene and 2- butene to increase propylene production, catalytic cracking of C4/C5 hydrocarbons to produce propylene and ethylene, automatic disproportionation of C4 hydrocarbons, oligomerization of butene, hydrogenation to produce alkyl oil, solid alkylation and other technologies, which provide strong technical support for the comprehensive utilization of C4 hydrocarbons. Due to the increasing demand for high-octane gasoline blending raw materials, the utilization of high-value fuel is still the most important way to apply C4 hydrocarbons for a long time.
Question 4: What kind of factory produces mixed C4-5 by-products? The first fraction of refining and chemical enterprises has mixed C4, and Yangzi Petrochemical, Qilu Petrochemical, Dushanzi Petrochemical, Daqing Petrochemical, Zhenhai Refinery and other units have it.
Question 5: Classification and economic value of 5:C4 products? Raw C4 produced by different methods can be divided into mixed C4 and refined C4. Mixed C4 is an important source of petrochemical attack, while C4 in refinery is mainly used to make fuel. Economically, mixed C4 olefins can convert butene 1 and butene 2 into butadiene by oxidative dehydrogenation technology, and further produce various rubbers. At the same time, Wison Engineering believes that by converting the relatively low-priced mixed C4 olefins in MTO plant into high-value dipropyl heptanol, it can also bring remarkable economic benefits to customers. On the other hand, the demand for MTBE, the blending raw material of high octane gasoline, is also increasing. For a long time, the utilization of high-value fuel is still the most important application mode of C4 hydrocarbons. For example, about 90% of butene is used as fuel, and only 10% is used in the chemical market.
Question 6: How is carbon four stored, temperature, pressure, liquid or gas? How is carbon four stored, temperature, pressure, liquid or gas? Thank you.
Solution 2: Is cyclobutane liquid or gas at normal temperature and pressure ... c), critical temperature-152.0l C, critical pressure 38OkPa ... Separating C4 fraction from petroleum cracking, such as naphtha with medium depth.
Question 7: Help, who knows how to separate isobutane from mixed C4? Hello, I don't know the answer to your question. I hope what I said is useful to you. I'm making MTBE for the time being, and C4 is distilled from liquefied petroleum gas. C4 directly enters MTBE production unit. C4 isobutylene reacts with methanol to produce MTBE. Other components hardly react with methanol. In this way, there is almost no residual isobutylene in C4 after the reaction, which enters into civil hydrocarbons.