Basic Science and Technology - Junior Secondary 2 - Crude oil and petrochemicals

TERM: 3^RD TERM

WEEK: 10

CLASS: Junior Secondary School 2

AGE: 13 years

DURATION: 40 minutes each for 2 periods

DATE:

SUBJECT: Basic Science

TOPIC: Crude oil and petrochemicals

SPECIFIC OBJECTIVES: At the end of the lesson, the learners should be able to

1. ) Define ‘crude oil’ and ‘petrochemicals’
2. ) Outline in details the step-by-step process of refining crude oil

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers, demonstration, story-telling, videos from source

INSTRUCTIONAL MATERIALS: Recommended Basic Science textbooks for Junior Secondary School 2

INSTRUCTIONAL PROCEDURES: PERIOD 1-2:

NOTE

CRUDE OIL AND PETROCHEMICALS

Crude Oil: Crude oil is a naturally occurring, unrefined petroleum product composed of a mixture of hydrocarbons, organic compounds, and impurities. It is extracted from underground reservoirs and is the raw material used for producing various fuels, chemicals, and other products. Crude oil can vary in composition and appearance, depending on its source.

Petrochemicals: Petrochemicals are chemical compounds derived from petroleum (crude oil) or natural gas. These chemicals are used as raw materials in the production of a wide range of products, including plastics, fertilizers, pharmaceuticals, synthetic fibers, and solvents. Petrochemicals are produced through processes such as cracking, polymerization, and distillation.

Step-by-Step Process of Refining Crude Oil:

The refining process involves separating and converting crude oil into useful products. The steps in refining crude oil include:

1. Distillation (Separation):
   • Crude oil is heated in a distillation column, where it is separated into different fractions based on boiling points. Lighter hydrocarbons (like gasoline) rise to the top of the column, while heavier fractions (like diesel and bitumen) settle at the bottom.
   • This process is called fractional distillation.
2. Cracking:
   • This process breaks down large, complex hydrocarbons into smaller, more useful ones. For example, heavy oils are cracked into gasoline, diesel, or other products. There are two main types of cracking:
     • Thermal Cracking: Uses heat to break down large molecules.
     • Catalytic Cracking: Uses a catalyst (substance that speeds up the reaction) to crack large molecules at lower temperatures.

3. Reforming:
   • In this step, hydrocarbons (such as naphtha) are chemically restructured to create high-quality gasoline components. The reforming process involves using a catalyst to rearrange or remove certain hydrogen atoms to produce better fuels.
4. Treating and Purification:
   • Various treatment processes are employed to remove impurities such as sulfur, nitrogen, and other contaminants from the products.
   • Hydrodesulfurization is commonly used to remove sulfur from gasoline and diesel.
5. Blending:
   • After the various fractions have been separated, cracked, and treated, they are blended together to form the final products like gasoline, diesel, jet fuel, and other petroleum-based products.
6. Conversion:
   • This process involves transforming heavier fractions into lighter, more valuable products. This is typically done through catalytic cracking or hydrocracking, both of which break down large molecules into smaller, more useful ones.
7. Storage and Distribution:
   • After refining, the final products are stored in tanks and distributed to various industries and consumers for use in manufacturing, transportation, and other applications.

EVALUATION:

1. What is the difference between crude oil and petrochemicals? Provide examples of each.
2. Explain the process of fractional distillation in the refining of crude oil. How are different products separated?
3. What are the main types of cracking in oil refining, and how do they contribute to the production of valuable fuels?
4. Why is the process of hydrodesulfurization important in the refining of crude oil?
5. Describe the final steps in the refining process, including blending and distribution, and explain their significance in producing usable products.

CLASSWORK: As in evaluation

CONCLUSION: The teacher marks their books and commends them positively