**Abstract**

The article describes the technology of synthesis of absolute ethyl alcohol, as well as the types, properties and efficiency of water-withdrawing reagents and types, properties and efficiency of reagents (CaO, tetraethoxytitanium), which chemically bind water and dehydrate ethanol. The composition and properties of the absolutized ethanol were studied using the infrared spectroscopy, mass spectroscopy and gas-chromatography. The octane number of gasoline with the addition of absolutized ethanol together with the combustion activator (diethyl ether) was measured as well. It has been shown that the content of even very small amounts (up to 2%) of the combustion activator in absolutized ethanol results in the increase of the octane number and improves running abilities of gasoline.

**Keywords:** technology, absolutized ethanol, calcium oxide, tetraethoxytitanium, diethyl ether, octane number

#### **1. Introduction**

Some methods for obtaining absolute alcohol are well known, namely: (1) by binding water to water by subtracting substances; (2) pressure absolutization on many column rectification (distillation) plants; (3) the so-called azeotropic rectification using methods based on the phenomenon of azeotropism of threecomponent systems; (4) using methods based on the phenomenon of vapor diffusion through porous partitions or molecular sieves [1, 2]. Using as a desiccant, calcined calcium oxide can achieve an ethanol concentration of 99.8%, using magnesium sawdust—89.95%. With the combined use of sodium alcoholate ethanol can be absolutized to 99.5% [3].

Another way to obtain absolute ethyl alcohol is to separate the mixtures in distillation columns operating at different pressure values. The method is based on the dependence of ethanol content in the mixture on pressure. Typically, the installation consists of two columns. In the first column receive the alcohol strength of 70–95%, which comes in second column under pressure. The pressure in different methods varies from 8 kPa to 7.6 MPa. It is in the second column that absolute alcohol (99.2%) is obtained. The absolute alcohol (99.2%) is obtained in the second column. The disadvantage of these methods is their high energy consumption, because the rectification columns operate under pressure and require of the using of vapor or other high-temperature media to provide the necessary parameters [4–10]. Many industrial distillation plants that produce absolute ethanol are azeotropic using a third component, which forms an azeotrope with the components of the

mixture—alcohol and water. Analysis of the literature shows that substances such as benzene, toluene, isooctane, cyclohexane and hexane can form the third component, which is capable of forming azeotropes with ethanol and water. The concentration of alcohol, obtained by this method, is reached to 99.7% [11–21].

Recently, ethanol production of Ukraine has decreased almost twice from 310 million liters in 1996 to 140 million liters in 2017. Today, 25% of the 80 distilleries with a total capacity of 480 million liters per year operate. To date, in Ukraine there are more than 40 licensed distilleries that can process 900,000 tons of grain per year and obtain 320 million liters of grain ethanol. The annual need of beet molasses is 1.1 million tons, from which you can get other 300 million liters of ethanol. In the structure of realization of rectified ethanol the largest part is occupied by vodka and ethanol from 81 to 94.5% in 2015. In January 2016, the manufacturer "Ukrspirt" produced more than 860,000 l of ethyl alcohol, 85,000 l of strong drinks and 756,000 l of car washers. At the same time, the company work is provided by 16

In recent years, the production of bioethanol has been steadily increasing. From

Macroeconomic analysis has shown that adding 20% of bioethanol to gasoline leads to an annual decrease in gasoline import by \$ 400 million, which will result in \$ 640 million increase in Ukraine's gross domestic product (GPD). Replacing 20% of heavy distillates with biodiesel will reduce imports by \$ 1 billion, which can

In August 2014, there were 13 enterprises operating in Ukraine that produced alcoholic fuels, 10 of which based on the state alcohol distilleries with a capacity of 23,700 tons/month. However, in August 2014 there was introduced 99 EUR tax on alternative gasoline in favor of importers and network monopolists, resulting in the fact that by the beginning of 2015 only two plants ("Haysinsky" and "Ekoeenergy") with a total capacity of 2700 tons/month worked [39]. The cost of growing rape grain in recent years ranged from 800 to 1200 UAH/t. At the same time, when the seed market price is 3000 UAH/t, the cost of production of biodiesel from the fossil is 11,000–12,000 UAH/t (about 10 UAH/l), which is 2.5 times lower than the existing prices for diesel oil from oil [40]. The dynamics of growth of bioethanol and biodiesel part in the world represented by the author [37] speaks for itself, so the production of bioethanol has exceeded 100 billion liters, and biodiesel amount

It is known that for homogenization of gasoline ethanol mixtures the third component is used. This component is aromatic hydrocarbons [41], which are added to ordinary gasoline to increase the octane number. In addition, it is not profitable, because the cost of toluene is by many times higher than the cost of absolute ethanol. As for the preparation of perfect mixtures of bioethanol and biodiesel with gasoline and diesel, only absolute ethanol (99.95%) must be used, therefore the research of new methods and reagents of ethanol absolutization is an actual problem and purpose of our work, which has a practical and economic value.

The properties of known oxygen-generating additives which activate the motor fuel combustion are presented in **Table 1** [38]. The table shows reagents which do

2000 to 2014 the amount of produced ethanol has increased by five times. The market leaders are: USA (corn), Brazil (sugar cane), Germany and France (sugar beet and grain). Governments of these countries intend to increase the bioethanol production by 70%. If 10% of bioethanol is added to gasoline, emissions of aerosol particles are reduced by 50% and carbon monoxide emissions by 30%. Therefore, there is a Directive 2009/28/EC, which requires up to 10% bioethanol in a motor fuel by 2020. Ukraine signed the Association Agreement with the European Union, so it should undertake the similar obligations. While in the EU this index is gradu-

ally approaching 5% in Ukraine, it does not exceed 1% [39].

*Improving the Technology of Synthesis Absolutized Bioethanol*

*DOI: http://dx.doi.org/10.5772/intechopen.92332*

increase Ukraine's GDP by \$ 1.4 billion.

reaches 30 billion liters.

**2. Experimental**

**223**

factories [38].

Others are the methods built on the application of the phenomenon of adsorption. For this purpose, the alcohol-water mixture should be converted into a vapor phase in which the water molecules are in dissociated form and can be separated by adsorbents that absorb only water molecules from the vapor mixture and can be regenerated for reuse. Such adsorbents include polymer compositions based on dioxols, silica gel, synthetic zeolites and the like. Technologically, they can be made in the form of membranes, which are ceramic tubes, the inner layer of which is covered with a thin layer of zeolite or in the form of molecular sieves. Different composition of synthetic zeolites is known, but aluminum-potassium and aluminum-sodium zeolites have become the most widely used because they have a high adsorption capacity [22–33]. Due to the high cost of synthetic zeolites, ethanol absolutization methods have been developed, using the so-called natural zeolites—clinoptilolite: (NaK)4CaAl6Si30O7224H2O and mordenite, which are widespread in the form of ores in certain territories of Ukraine, which is an undeniable advantage of their use [34].

Due to stabilization production of the volume petroleum and decrease in its price and the ban on the use of the tetraethyl lead gasoline in recent years, many countries of the world tend to increase the usage of oxygen-containing compounds as the additions in commercial high-octane gasoline. Methyl (MA), ethyl (EA) and tert-butyl (TBA) alcohols, methyl tert-butyl ether (MTBE), having high octane numbers and low boiling points are quite widely used among the oxygen-containing compounds. The usage of these additions results in an increase of the octane number and the improvement of the oxygen coefficient and the efficiency of the fuel combustion. All types of the fuel with oxygen-generating additives reduce the release of carbon monoxide (CO) and unburnt fuel parts (C) into the atmosphere. Thus, the addition of 10–15% MTBE reduces CO content in exhaust gases by 20%. The use of alcohol-gasoline mixtures as a motor fuel is also promising. The world ethanol production has recently reached 90 million m<sup>3</sup> per year [35]. The main producers are the USA, Brazil and India. It should be noted that more than 80% of produced ethanol is used as a component of motor fuels (fuel ethanol). The rest is used for manufacture of the strong drinks, solvents, the ethyl ethers and esters synthesis and as a raw material for organic synthesis [36].

In many countries of the world, gasoline with 10–15% of various fuel additives is already used. In particular, a mixture of gasoline and ethanol (10–12%) is successfully used in the USA, Canada and Brazil, where its production is based on a national program. In the United States, 80% of produced ethanol is used as a fuel. In France, fuel containing ethanol (5%) is used too. Ukraine consumes around 200 million tons of fuel and energy resources annually and has a deficit of energy resources because the needs for energy consumption are covered only up to 53% by its own resources. The rest is covered by import: 75% of the required volume of natural gas and 85% of crude oil and petroleum products. Such a structure of the energy economy creates Ukraine's dependence on oil and gas exporters and is threatening its energy and national security. Motor transport occupies a leading place in the transportation of goods. The prognosis of the development of Ukraine's motor car park proves the tendency toward a steady increasing of the number of cars and fuel consumption. In 2016, the total motor car park and the park of light commercial vehicles in Ukraine consist of, according to AUTO-Consulting, 9121,000 cars, which consume 32.7 million tons of motor fuel. The alcohol industry of Ukraine fully provides internal needs of alcohol for the manufacture of alcoholic drinks, working only up to 30% of its total capacity [37].

mixture—alcohol and water. Analysis of the literature shows that substances such as benzene, toluene, isooctane, cyclohexane and hexane can form the third component, which is capable of forming azeotropes with ethanol and water. The concen-

Others are the methods built on the application of the phenomenon of adsorption. For this purpose, the alcohol-water mixture should be converted into a vapor phase in which the water molecules are in dissociated form and can be separated by adsorbents that absorb only water molecules from the vapor mixture and can be regenerated for reuse. Such adsorbents include polymer compositions based on dioxols, silica gel, synthetic zeolites and the like. Technologically, they can be made in the form of membranes, which are ceramic tubes, the inner layer of which is covered with a thin layer of zeolite or in the form of molecular sieves. Different composition of synthetic zeolites is known, but aluminum-potassium and aluminum-sodium zeolites have become the most widely used because they have a high adsorption capacity [22–33]. Due to the high cost of synthetic zeolites, ethanol absolutization methods

tration of alcohol, obtained by this method, is reached to 99.7% [11–21].

*Analytical Chemistry - Advancement, Perspectives and Applications*

have been developed, using the so-called natural zeolites—clinoptilolite:

synthesis and as a raw material for organic synthesis [36].

drinks, working only up to 30% of its total capacity [37].

**222**

(NaK)4CaAl6Si30O7224H2O and mordenite, which are widespread in the form of ores in certain territories of Ukraine, which is an undeniable advantage of their use [34]. Due to stabilization production of the volume petroleum and decrease in its price and the ban on the use of the tetraethyl lead gasoline in recent years, many countries of the world tend to increase the usage of oxygen-containing compounds as the additions in commercial high-octane gasoline. Methyl (MA), ethyl (EA) and tert-butyl (TBA) alcohols, methyl tert-butyl ether (MTBE), having high octane numbers and low boiling points are quite widely used among the oxygen-containing compounds. The usage of these additions results in an increase of the octane number and the improvement of the oxygen coefficient and the efficiency of the fuel combustion. All types of the fuel with oxygen-generating additives reduce the release of carbon monoxide (CO) and unburnt fuel parts (C) into the atmosphere. Thus, the addition of 10–15% MTBE reduces CO content in exhaust gases by 20%. The use of alcohol-gasoline mixtures as a motor fuel is also promising. The world ethanol production has recently reached 90 million m<sup>3</sup> per year [35]. The main producers are the USA, Brazil and India. It should be noted that more than 80% of produced ethanol is used as a component of motor fuels (fuel ethanol). The rest is used for manufacture of the strong drinks, solvents, the ethyl ethers and esters

In many countries of the world, gasoline with 10–15% of various fuel additives is already used. In particular, a mixture of gasoline and ethanol (10–12%) is successfully used in the USA, Canada and Brazil, where its production is based on a national program. In the United States, 80% of produced ethanol is used as a fuel. In France, fuel containing ethanol (5%) is used too. Ukraine consumes around 200 million tons of fuel and energy resources annually and has a deficit of energy resources because the needs for energy consumption are covered only up to 53% by its own resources. The rest is covered by import: 75% of the required volume of natural gas and 85% of crude oil and petroleum products. Such a structure of the energy economy creates Ukraine's dependence on oil and gas exporters and is threatening its energy and national security. Motor transport occupies a leading place in the transportation of goods. The prognosis of the development of Ukraine's motor car park proves the tendency toward a steady increasing of the number of cars and fuel consumption. In 2016, the total motor car park and the park of light commercial vehicles in Ukraine consist of, according to AUTO-Consulting,

9121,000 cars, which consume 32.7 million tons of motor fuel. The alcohol industry of Ukraine fully provides internal needs of alcohol for the manufacture of alcoholic

Recently, ethanol production of Ukraine has decreased almost twice from 310 million liters in 1996 to 140 million liters in 2017. Today, 25% of the 80 distilleries with a total capacity of 480 million liters per year operate. To date, in Ukraine there are more than 40 licensed distilleries that can process 900,000 tons of grain per year and obtain 320 million liters of grain ethanol. The annual need of beet molasses is 1.1 million tons, from which you can get other 300 million liters of ethanol. In the structure of realization of rectified ethanol the largest part is occupied by vodka and ethanol from 81 to 94.5% in 2015. In January 2016, the manufacturer "Ukrspirt" produced more than 860,000 l of ethyl alcohol, 85,000 l of strong drinks and 756,000 l of car washers. At the same time, the company work is provided by 16 factories [38].

In recent years, the production of bioethanol has been steadily increasing. From 2000 to 2014 the amount of produced ethanol has increased by five times. The market leaders are: USA (corn), Brazil (sugar cane), Germany and France (sugar beet and grain). Governments of these countries intend to increase the bioethanol production by 70%. If 10% of bioethanol is added to gasoline, emissions of aerosol particles are reduced by 50% and carbon monoxide emissions by 30%. Therefore, there is a Directive 2009/28/EC, which requires up to 10% bioethanol in a motor fuel by 2020. Ukraine signed the Association Agreement with the European Union, so it should undertake the similar obligations. While in the EU this index is gradually approaching 5% in Ukraine, it does not exceed 1% [39].

Macroeconomic analysis has shown that adding 20% of bioethanol to gasoline leads to an annual decrease in gasoline import by \$ 400 million, which will result in \$ 640 million increase in Ukraine's gross domestic product (GPD). Replacing 20% of heavy distillates with biodiesel will reduce imports by \$ 1 billion, which can increase Ukraine's GDP by \$ 1.4 billion.

In August 2014, there were 13 enterprises operating in Ukraine that produced alcoholic fuels, 10 of which based on the state alcohol distilleries with a capacity of 23,700 tons/month. However, in August 2014 there was introduced 99 EUR tax on alternative gasoline in favor of importers and network monopolists, resulting in the fact that by the beginning of 2015 only two plants ("Haysinsky" and "Ekoeenergy") with a total capacity of 2700 tons/month worked [39]. The cost of growing rape grain in recent years ranged from 800 to 1200 UAH/t. At the same time, when the seed market price is 3000 UAH/t, the cost of production of biodiesel from the fossil is 11,000–12,000 UAH/t (about 10 UAH/l), which is 2.5 times lower than the existing prices for diesel oil from oil [40]. The dynamics of growth of bioethanol and biodiesel part in the world represented by the author [37] speaks for itself, so the production of bioethanol has exceeded 100 billion liters, and biodiesel amount reaches 30 billion liters.

It is known that for homogenization of gasoline ethanol mixtures the third component is used. This component is aromatic hydrocarbons [41], which are added to ordinary gasoline to increase the octane number. In addition, it is not profitable, because the cost of toluene is by many times higher than the cost of absolute ethanol. As for the preparation of perfect mixtures of bioethanol and biodiesel with gasoline and diesel, only absolute ethanol (99.95%) must be used, therefore the research of new methods and reagents of ethanol absolutization is an actual problem and purpose of our work, which has a practical and economic value.
