Sodium silicate or "water glass" or liquid glass, originates in ancient practices. A chemical compound, sodium silicate is composed of sodium (Na) and silica (SiO2), often in the form of a water-soluble gel or solid.
It's created through fusion of sodium carbonate with silicon dioxide at high temperatures. The resultant product has a glassy look and dissolves in water, creating a thick solution. The formula can differ, leading to a variety of silicate products with distinct properties.
Available in liquid, solid, or powder forms, sodium silicate plays an essential role in many areas, such as construction, healthcare, and manufacturing. Its ability to bond surfaces makes it an ingredient in adhesives and sealants. It's also used to preserve historical artifacts.
Properties of Sodium Silicate
Sodium silicate has several notable properties, making it an incredibly versatile compound. These include:
Solubility: Sodium silicate is highly soluble in water, forming an alkaline solution that can be adjusted to various pH levels.
Viscosity: Depending on concentration, sodium silicate can vary from a thin liquid to a thick gel.
Adhesive Qualities: Its adhesive properties make it an effective binder in numerous applications, from construction materials to art supplies. It can bond materials like wood, metal and glass.
Chemical Stability: Sodium silicate is chemically stable under most conditions, resisting degradation from acids and organics.
Thermal Resistance: It exhibits excellent resistance to high temperatures, enhancing its usability in applications involving heat.
Alkalinity: Its alkaline properties help neutralize acids, making it valuable in chemical processes, such as in the production of detergents.
Durability: Once dried, sodium silicate forms a strong, glass-like solid that resists decay and maintains its structure over time, which is useful for long-lasting applications.
Versatility: Sodium silicate's unique properties allow it to be used in various sectors, such as agriculture, manufacturing, and health care. For example, it can enhance soil quality, improve detergent formulations, and serve as a binder in paper production.
Is Sodium Silicate the Same as Glass?
While sodium silicate is often referred to as glass, it's not the same as traditional silica glass, such as window glass. Silica glass is composed of pure silicon dioxide (SiO2) and undergoes a different manufacturing process.
Glass is a solid made by heating silica and other materials at high temperatures, usually above 1000 °C. Sodium silicate can be viewed as a type of water glass but does not have the same rigidity or durability as traditional glass.
Sodium silicate has sodium content and is created by combining sodium carbonate and silicon dioxide. Both materials share similar properties due to their silicon-oxygen network structure, which gives them a glass-like quality.
Distinctions appear in structures and applications. Glass is used for windows, packaging, and cookware due to transparency and strength. Sodium silicate excels in adhesive and sealant applications. It dries hard and glassy but lacks the clarity of standard glass.
How to Make Sodium Silicate
Sodium silicate can be synthesized through a chemical reaction that involves heating sodium carbonate and silica (sand) at temperatures. Silica melts at up to 1723 °C (3133 °F). To reduce the melting point of silica, a flux of sodium carbonate is needed.
Sodium carbonate decomposes on heating to form sodium oxide (Na2O) and carbon dioxide (CO2). By adding 25 percent of the sodium oxide to silica, melting point reduces from 1723 to 850 °C (3,133 to 1562 °F).
Sodium carbonate can be created by heating sodium bicarbonate or baking soda. Heat baking soda in an oven at 93.5 °C (200 °F) for about an hour. Carbon dioxide and water will gradually depart, leaving dry sodium carbonate. This is the soda ash.
A process to make sodium silicate:
Materials Required: Obtain sodium carbonate (soda ash) and silica (silicon dioxide).
Mixing: Combine equal parts of sodium carbonate and silica in a furnace.
Heating: Heat the mixture until it melts, typically around 1100°C.
Cooling: Allow the mixture to cool. It will solidify into a glass-like substance.
Dissolving: For the liquid form, dissolve the solid sodium silicate in water.
A similar method using lye and silica sand:
Materials Needed: You will need sodium hydroxide (NaOH), aka caustic soda or lye and silica sand (SiO2) or sodium carbonate (soda ash).
Heating: In a heat-resistant container, mix sodium hydroxide with silica sand. A common ratio is one part sodium hydroxide to two parts silica.
Reaction Process: Heat this mixture to about 800-1000 °C (1472-1832 °F). The heat triggers a reaction producing sodium silicate.
Cooling: Once blended and reacted, let the mixture cool down. After cooling, it can be ground into a fine powder or dissolved to create liquid sodium silicate.
History & Uses in Alchemy
Ancient civilizations use sodium silicate to bind ceramics and in glassmaking. Evidence of applications appear in pottery preservation and waterproofing.
Historically, sodium silicate is used in alchemical processes. The term "water glass" can also be traced back to alchemy in medieval practice. Glass production has been around since Neolithic times and its use accelerates in ancient Alexandria and more modern Renaissance.
European alchemists in the 16th century observe soluble silicates of alkali metals such as sodium or potassium. In 1567, Giambattista della Porta notes cream of tartar (potassium bitartrate) causes quartz to melt at a lower temperature.
Early mentions of alkali silicates also come from Basil Valentine in 1520 and Agricola in 1550. Jan Baptist van Helmont, c. 1640, describes production of alkali silicates by melting sand with excess alkali, and demonstrates precipitation of silica by adding acid.
Silica is a prevalent mineral found in the earth's crust, with glass, beach sand, silicone, and granite being examples of silica-based materials. Silica exists in two forms:
crystalline: crystalline silica is found in various materials such as sand, gravel, clay, granite
noncrystalline: non-crystalline silica is found in glass, silicon carbide, and silicone
Crystalline substances exhibit a structured 3D array of atoms in orderly and periodic ways. Generally, metals, many ceramics and some polymers are classed as crystalline. In contrast, noncrystalline materials lack periodic arrangement of atoms, showing a random order.
In 1646, Glauber produces potassium silicate, which he calls liquor silicum, by melting potassium carbonate, obtained from calcinated cream of tartar, and sand in a crucible until no more bubbles are released due to the escape of carbon dioxide.
The resulting mixture is cooled and ground to a fine powder. Upon exposure to moist air, it transforms into a viscous liquid Glauber calls "Oleum oder Liquor Silicum, Arenæ, vel Crystallorum" or "oil or solution of silica, sand, or quartz crystal".
Modern Uses
Today, sodium silicate is widely used across multiple industries:
Water Glass: Sodium silicate solutions are often known as "water glass," playing a significant role in architectural glass and modern sealing products.
Construction: Employed as a binding agent in cement, concrete, and adhesives. It acts as a waterproofing agent and is added to concrete to boost its strength and durability, reducing cracking by 15-30%.
Soap and Detergent Manufacturing: Serves as a builder in cleaning products, enhancing performance of detergents. Its alkaline nature makes sodium silicate effective in detergent formulations. It helps soften water, which can improve stain removal by up to 20%.
Automotive: Used in brake linings and seals to provide durability and heat resistance.
Packaging: Beneficial as a barrier coating in various packaging materials.
Fireproofing: Often deployed in fire-resistant materials due to its heat-resilient properties.
Agriculture: Acts as a soil conditioner, improving nutrient and moisture retention. It enhances nutrient availability, leading to crop yield improvements of about 10-15%.
Paper and Wood Treatment: Sodium silicate is used in making paper products, ensuring better quality and bonding of fibers. It also protects wood against pests, increasing its lifespan.
Healthcare: In medicine, sodium silicate is part of some pharmaceuticals, helping in drug formulation and delivery systems due to its bonding properties.
Facts About Sodium Silicate
Environmental Friendliness: Sodium silicate is considered eco-friendly as it does not contribute to environmental pollution when properly used. It is also a product in cleanup processes, helping manage chemical spills effectively thanks to its absorbent qualities.
Non-Toxic: It is generally recognized as safe for various applications. Unlike many industrial chemicals, sodium silicate is non-toxic and safe for household products, such as all-purpose cleaners and laundry detergents.
Versatile Formulations: Sodium silicate can be formulated in a variety of grades and concentrations, making it adaptable for specific needs in industries.
Thermal Stability: Sodium silicate can withstand temperatures higher than many synthetic polymers. This quality makes it suitable for high-temperature scenarios, such as in steel manufacturing.
pH Neutralization: Its alkaline nature neutralizes acids effectively, making it beneficial in various chemical processes and environmental cleanup efforts.
Non-Fiction Books:
Fiction Books:
READ: Lora Ley Adventures - Germanic Mythology Fiction Series
READ: Reiker For Hire - Victorian Detective Murder Mysteries