Question

Write the equation for the synthesis of ethanol from ethylene. What are some commercial uses of ethanol made by this process?

Short answer

The synthesis of ethanol from ethylene occurs through the hydration process, which can be represented by the chemical equation: \(C_2H_4 (g) + H_2O (l) \rightarrow C_2H_5OH (l)\). Some commercial uses of ethanol produced by this process include fuel (gasoline additive or substitute), solvents, disinfectants and cleaners, food and beverages, and applications in the pharmaceutical industry.

Step-by-step solution

1. Write the chemical formulas of ethanol and ethylene

The chemical formula of ethanol is C_2H_5OH, and the chemical formula of ethylene is C_2H_4.

2. Write the chemical reaction for the synthesis of ethanol from ethylene

The synthesis of ethanol from ethylene can be achieved by using a process called hydration. In this process, ethylene and water (H_2O) react in the presence of an acid catalyst, usually sulfuric or phosphoric acid, to form ethanol. The chemical reaction can be written as follows: \(C_2H_4 (g) + H_2O (l) \rightarrow C_2H_5OH (l)\) Here, C_2H_4 (g) = Ethylene gas H_2O (l) = Liquid water C_2H_5OH (l) = Liquid ethanol

3. Discuss some commercial uses of ethanol made by this process

Some commercial uses of ethanol produced by the synthesis from ethylene include: 1. Fuel: Ethanol is commonly used as a gasoline additive or substitute called Ethanol fuel (E10 or E85). It helps in reducing greenhouse gas emissions, increases the octane rating of gasoline, and reduces the dependence on fossil fuels. 2. Solvents: Ethanol works as an industrial solvent, and it is used in the manufacturing of inks, paints, varnishes, and other products. 3. Disinfectants and cleaners: Ethanol is a common ingredient in many antiseptic wipes, hand sanitizers, and other cleaning products owing to its ability to kill bacteria, fungi, and viruses. 4. Food and beverages: Beverage-grade ethanol is used in alcoholic beverages like wines, spirits, and liquors as a key ingredient. It is also used as an extraction solvent in the food industry for the production of flavors and colorings. 5. Pharmaceutical industry: Ethanol is widely used in various medical and pharmaceutical applications, such as an extraction solvent for the preparation of medicines and a preservative in pharmaceutical formulations.

Key concepts

Chemical Reactions in Ethanol Production

Understanding the fundamentals of chemical reactions is essential when looking at the synthesis of ethanol from ethylene. Chemical reactions are processes where reactants transform into products through the breaking and forming of chemical bonds. In the case of ethanol production, ethylene (C₂H₄) reacts with water (H₂O) in the presence of an acid catalyst, such as sulfuric or phosphoric acid.

The hydration reaction, represented by the equation \(C_2H_4 (g) + H_2O (l) \rightarrow C_2H_5OH (l)\), is an example of an addition reaction where a molecule of water adds across the double bond of ethylene, resulting in the formation of ethanol. Understanding this reaction requires knowledge of how acid catalysts facilitate the process and how the structural changes occur at a molecular level during the conversion.

Furthermore, the reaction conditions, such as temperature, pressure, and concentrations, can have significant effects on the reaction rate and yield. The manipulation of these conditions is a crucial aspect of chemical engineering and plays a pivotal role in optimizing the industrial production of ethanol.

Industrial Applications of Ethanol

Ethanol's versatility extends beyond the laboratory, as it holds a significant spot in various industrial sectors. As a biofuel, ethanol is blended with gasoline to produce mixtures like E10 or E85, offering a renewable energy alternative that can help reduce carbon emissions and mitigate the impact of climate change. This application leverages ethanol's high octane number as a performance enhancer for engines, reducing the need for fossil fuels and supporting energy sustainability.

In addition to its role as a fuel, ethanol serves as a powerful solvent in the production of inks, paints, varnishes, and cosmetic products.

Medical and Sanitary Uses

Its germicidal properties make it indispensable in the manufacture of sanitizing products. Ethanol is found in hand sanitizers, antiseptic wipes, and cleaning agents due to its efficacy in eliminating pathogens. This became particularly evident during global health crises, where demand for sanitation supplies surged.

The food and beverage industry relies on ethanol for the production of alcoholic drinks and extracts, showcasing its importance in both culture and commerce. Furthermore, its utility in the pharmaceutical field, as both a solvent and preservative, underlines ethanol’s integral part in maintaining health and treating illness.

Hydration Process in Organic Chemistry

The hydration process in organic chemistry involves the addition of water to an organic molecule. Specifically, in the production of ethanol, hydration refers to the addition of water to ethylene. The double bond in ethylene is electron-rich, allowing the acidic catalyst to protonate it and make it more susceptible to nucleophilic attack by water molecules.Through this mechanism, the double bond is opened up, and a hydroxyl group (-OH) becomes attached to one of the carbon atoms, thus transforming the hydrocarbon into an alcohol. The acid catalyst plays a crucial role in the mechanism by both facilitating the reaction and providing the hydronium ion necessary for the protonation of ethylene. The hydration process is not only pivotal in producing ethanol but is also a common method in synthesizing various types of alcohols, demonstrating its broad utility in organic synthesis.