Glass and Paper Manufacturing Processes & Chemical Industry Overview

Glass Manufacturing

Key Concepts in Glass Production

Glasses containing cuprous oxide have a red color.

The process used in the manufacture of glass is called continuous casting.

The most common fining agents used in glass manufacturing include nitrate and sodium antimony.

Opalescent substances commonly used in glass manufacturing include sodium silicate, cryolite, and calcium fluoride.

In glassmaking, soda ash and sodium sulfate act as fluxes.

Modern glass consists of a mixture of calcium oxide, sodium carbonate, and silica.

Bleaching agents used in glass manufacturing include manganese dioxide and selenium.

Types of Substances Used in Glassmaking

Vitrifiers: These substances transition from a crystalline structure to an amorphous structure under the action of heat.

Fining Agents: These are added to create a more stable and less reactive glass (e.g., calcium carbonate, magnesium carbonate, barium oxide, aluminum oxide). Common fining agents include arsenious oxide, antimony, sodium nitrate, potassium nitrate, and sodium sulfate.

Bleaches: These are used to remove color caused by the presence of iron.

Colorants: Examples include cobalt oxide for blue, iron oxide for amber, cuprous oxide for red, cupric oxide for green, and chromic oxide for green.

Opalescents: These give glass its opacity.

Stabilizers: These are added to the vitrifier and fluxes to enhance glass stability.

Fluxes: These are added to the vitrifier to improve melting.

Paper Manufacturing

Key Concepts in Paper Production

In papermaking, water is removed by dripping, suction, and pressing.

In the manufacture of paper, wood pulp is obtained after the cooking and digestion process.

Mechanical pulp is obtained by the defibration of wood.

The difference between brown paper and fine paper is: Brown paper is more economical and of lower quality, while fine paper is scarcer and of better quality.

Chemical Industry in Food

Key Concepts in Food Chemistry

In the food industry, additives are used to maintain the flavor and appearance of foods.

Types of Additives

Emulsifiers: These prevent fat and water from separating.

Additives: These halt the decomposition process and maintain the taste and appearance of foods.

Colorings: These add color to food. Because they are natural pigments, they can decompose and lose their color.

General Chemical Industry Overview

Characteristics of Basic Chemical Industries

• Generate intermediate products.
• Use raw materials of organic and inorganic origin, including natural raw materials.
• Create products in large quantities at low cost.

Common fluxes used in glass manufacturing include sodium carbonate and sodium sulfate.

Fining agents are used for the elimination of bubbles.

Glass is considered an amorphous solid because it is a supercooled liquid that is not crystalline, and its molecules are closely packed together.

Chemical Change Industries

These industries manufacture products that undergo physical and chemical changes, producing goods for daily consumption.