Problem 55 - A Complete Resource Book in Chemistry for JEE Main

Question

Which catalyst is used in the manufacture of sulphuric acid by Contact Process? (a) Ni powder (b) Platinized asbestos (c) anhydrous \(\mathrm{Al}_{2} \mathrm{O}_{3}\) (d) Al powder

Step-by-Step Solution

Answer

The catalyst used in the Contact Process is Platinized asbestos.

Step 1: Understanding the Contact Process

The Contact Process is the industrial method used to produce sulfuric acid, one of the most important chemicals in the industry. This process involves multiple steps, including the oxidation of sulfur dioxide (SO₂) to sulfur trioxide (SO₃), which is catalyzed by a specific material.

Step 2: Identifying the Role of the Catalyst

In the Contact Process, the catalyst is essential for converting SO₂ to SO₃ efficiently. This catalyst must be able to withstand high temperatures and facilitate the reaction rate without being consumed in the process.

Step 3: Reviewing Catalyst Options in the Question

The options listed are: (a) Ni powder, (b) Platinized asbestos, (c) anhydrous Al₂O₃, and (d) Al powder. Among these, we need to determine which catalyst is commonly used in the Contact Process.

Step 4: Identifying the Correct Catalyst

The most common catalyst used in the Contact Process is vanadium(V) oxide, V₂O₅. However, in the given options, the most relevant catalyst used historically is (b) Platinized asbestos.

Key Concepts

Sulfuric Acid

Sulfuric acid, with the chemical formula \( \text{H}_2\text{SO}_4 \), is one of the most important chemicals in industrial applications. It is often considered the "king of chemicals" due to its wide range of uses. This acid is a key component in manufacturing fertilizers, such as ammonium sulfate and superphosphate, which are essential for agriculture.

Besides agriculture, sulfuric acid is also used in:

• Petroleum refining to remove impurities,
• Production of chemicals like hydrochloric acid and nitric acid,
• Manufacturing of detergents and explosives,
• Metal processing and purification industries.

Due to its vital role, efficient production methods, like the Contact Process, are essential for the global supply of sulfuric acid. The Contact Process enables the large-scale production necessary to meet industrial demands.

Catalyst

In industrial chemistry, catalysts are substances that speed up chemical reactions without being consumed in the process. In the Contact Process specifically, catalysts play a crucial role in converting sulfur dioxide \(\text{SO}_2\) to sulfur trioxide \(\text{SO}_3\). This is an important step because \(\text{SO}_3\) is later converted into sulfuric acid.

The choice of catalyst is vital to ensure the reaction is efficient and fast. A good catalyst should:

• Promote a faster reaction rate,
• Be stable and withstand high temperatures,
• Remain unchanged at the end of the reaction,
• Prove cost-effective for large-scale operations.

The historical catalysts include platinized asbestos and the more contemporary vanadium(V) oxide \(\text{V}_2\text{O}_5\). These substances help in achieving the reaction conditions necessary for the optimal production of sulfur trioxide.

Industrial Chemistry

Industrial chemistry involves the large-scale production of chemicals that are crucial for both consumer products and industrial applications. At its heart, industrial chemistry focuses on converting raw materials into valuable products through chemical reactions. The Contact Process is a prime example of industrial chemistry in action, where high production efficiency is critical.

Some key principles in industrial chemistry include:

• Optimization of reaction conditions to maximize yield and efficiency,
• Minimization of waste and environmental impact,
• Economical considerations for cost-effective production,
• Ensuring safety and sustainability in manufacturing processes.

The scale at which processes like the Contact Process operate requires careful planning and design, involving choices about catalysts, reactant handling, and heat management. Overall, industrial chemistry ensures that society's chemical needs are met safely and sustainably.