ANALYSIS OF MODERN TECHNOLOGIES OF METHYL TERTIARY BUTYL ETHER PRODUCTION

ABSTRACT

The number of high-octane gasoline fractions required by the market is constantly growing. The constant increase in gasoline consumption entails considering the creation of a complete set of processes for the production of high-octane gasoline fractions at oil refineries as a possible option. This path requires significant investments in the modernization of technological processes. During the research work, effective proposals were given for the production of methyl tert-butyl ether (MBE), based on a number of proposals from individual companies and accurate calculations. At the same time, detailed information is provided on the most modern trends in television and radio production. In addition, certain shortcomings in this field have been studied and ways to solve them using effective methods have been found.

АННОТАЦИЯ

Количество высокооктановых фракций бензина, необходимых рынку постоянно растёт. Постоянное увеличение потребления бензинов влечёт за собой рассмотрение, как возможного варианта, создания полного набора процессов производства высокооктановых бензиновых фракций на нефтеперерабатывающих заводах. Этот путь требует значительных инвестиций в модернизацию технологических процессов. В ходе научно-исследовательской работы были даны эффективные предложения по направлениям производства метил-трет-бутилового эфира (МБЭ), основанные на ряде предложений отдельных компаний и точных расчетах. При этом представлена подробная информация о самых современных тенденциях телерадиопроизводства. Кроме того, были изучены определенные недостатки в этой области и найдены пути их решения с помощью эффективных методов.

Keywords: tetraethyl lead, methyl tert-butyl ether (MTBE), gasoline, hydrocarbons, synthesis, oxygenate, mixture, alcohol, ether, amine, detonation resistance, octane number, heater, cooler

Ключевые слова: тетраэтилсвинец, метилтретбутиловый эфир (МTБЭ), бензин, углеводороды, синтез, оксигенат, смесь, спирт, эфир, амин, детонационная устойчивость, октановое число, нагреватель, охладитель

Introduction. Environmental problems encourage us to be careful with nature, so it requires us to produce safe and economically useful fuels. Therefore, the production of motor fuels is undergoing significant changes.

Governments of many countries are developing several laws to improve the environment. In world practice, the idea of producing environmentally friendly motor fuel leads to setting new requirements for fuel quality improvement. For example, in the EU countries, the main restrictions are set for tetraethyl lead. This substance is used as a high-octane additive for motor fuels. The detonation stability of gasoline is very important for the octane number. High detonation stability plays an important role for the process to be completely normal. If the unburned part of gasoline is not stable enough, rapid decomposition may occur as a result of the accumulation of peroxide compounds. Thermal expansion, in turn, is caused by the spontaneous combustion of fuel, and it causes rapid combustion and the phenomenon called detonation.

Objects and methods of research: Detonation - causes the engine to overheat, decay and eventually fail. Therefore, it is very important to prepare the fuel composition. In order to be competitive in refineries in the countries of the world, detonation stability is an important quality indicator, and also the environmental characteristics of automobile gasoline must be in common with the requirements of the world market. In addition, only the production of unleaded gasoline does not mean the creation of environmentally friendly technology.Limiting tetraethyl lead is not enough to meet world standards. This is achieved by limiting the amount of aromatic hydrocarbons, especially benzene, and replacing aromatic hydrocarbons with isoparaffin hydrocarbons. The octane number of gasoline is determined using an oxygenate additive (MTBE, MTAE, DEPE, etc.). These substances make it possible to reduce carbon monoxide in exhaust gases. Methyl tert-butyl ether (2-methyl-2-methoxypropane) (CH₃)₃COCH₃ is one of the most effective substances. As an additive for motor fuel, it is considered very effective. If almost all low-oxygen compounds have an octane number of 100 (RM), MTBE can reach 135 (RM) depending on the hydrocarbon content of gasoline.

During the production of gasoline, MTBE reduces oil consumption, and this reduction leads to a reduction in the requirements for octane, the conventionality of the hydrocarbon composition of gasoline.

Results and its discussion: The general chemical mechanism for the synthesis of MTBE is as follows:

The reaction is at 60-80^oC and 4-12atm. goes under pressure.

The technological scheme of MTBE consists of 2 parts (Fig. 1). In the first chain, the release of esters and direct synthesis takes place, in the second chain, unreacted hydrocarbons are purified from alcohol and the alcohol is returned to the process. In the technological scheme, separation and synthesis of ethers is carried out in k-3 reaction-distillation column, this device consists of 2 parts. The rectification process takes place in part 1, and the reaction takes place in part 2.

The hydrocarbon fraction is mixed with pure alcohol and transferred to the adiabatic evaporator R-1. This equipment is a porous, cylindrical device filled with a catalyst. Due to the evaporation of the reaction mass, various amounts of heat are lost in the range from 30-40⁰C to 70-80⁰C. The evaporation process is controlled by the pressure in the reactor.

In the flow from R-1 to 2, the vapor-liquid mixture is introduced from under the catalyst layer of the K-3 column. This column consists of 3 parts: methanol and ethers are separated from unreacted hydrocarbons in the upper layer; synthesis and their release takes place in the middle layer filled with catalyst. In the second part, the process of separation of methyl tertiary ether from methanol and C4 hydrocarbons is carried out.

Figure 1. Scheme of the MUBE synthesis process at Yarsintez Institute

In the K-3 column, the catalyst is placed in 3 layers on the base distribution plates. Methanol is fed to the top of the catalyst layer. The butane-butylene fraction is removed from the top of the column and sent to the aqueous washing column K-4. C-4 fraction from methanol is washed there with water. The finished product, i.e. ether, is extracted from the lower part of the K-3 column. Column 4 is supplied with water from the top, and the washed hydrocarbon fraction is removed and sent to the dehydrogenation process.

Wash water mixed with alcohol is removed from the bottom of the K-4 column and fed to the K-5 methanol regeneration column as a feed. Heat control in the column is carried out using water flow.

The alcohol from the top of the K-5 column is mixed with pure methanol. The aqueous mixture is fed from the lower part of K-5 to the upper part of the K-4 column.

Conclusion. The process is carried out with the help of a porous catalyst with a rough surface, and this gives us an opportunity to apply the catalytic distillation process. This technology represents the resistance of the reagents and local heat loss, and therefore the thermodynamic resistance can be overcome. As a result of the heat of the exothermic reaction, it will be possible to expel the products and continue the separation process. The concentration of MUBE in the final product will be 99%.

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