Caustic soda, so-called lye or sodium hydroxide in the industry, is an inorganic chemical compound with the formula NaOH. The manufacturing of numerous daily things now frequently uses caustic soda as a component. It is commonly referred to as lye and has been used for generations in manufacturing soap. Due to its capacity to dissolve grease, it is also frequently used in oven cleaners and drain-unclogging solutions. So, many enterprises rely upon the properties of this substance to present a superior outcome in the market.
Before going through our topic, which is related to caustic soda, it is worth talking about a reliable manufacturer, supplier, and exporter of this substance. JAM Group Co. is a reputable caustic soda manufacturer and exporter that employ high-quality raw materials and cutting-edge technologies to provide you with a premium product. Every company can count on our products as well-formed outcomes from a flawless supply chain. JAM Group caustic soda is produced under the constant monitoring of skilled chemists in our equipped factories in Eastern Europe, Poland, and the Middle East. The products will pass a series of tests to verify its claimed properties, and then they will be sent to in-demand customers worldwide with reliable shipments.
What is Caustic Soda?
Caustic soda is one of the common names for Sodium Hydroxide (NaOH), which is also known as lye. Its common name derives from its chemical identity as it consists of sodium cations na+ and hydroxide anions oh-. It is a white solid ionic compound which is caustic or corrosive. In pure form, it readily absorbs water and forms aqueous solutions. Commercially available caustic soda or sodium hydroxide is usually sodium hydroxide monohydrate, NaOH·H2O.
- Sodium Hydroxide Density: 2.13 g/cm3
- Sodium Hydroxide Melting Point: 604.4°F
- Sodium Hydroxide Boiling Point: 2,530°F
- Molar Mass of Sodium Hydroxide: 39.997 g/mol
- Density: 2.13 g/cm³
- Formula: NaOH
- Specific gravity 2.13 at 25°C
- Solubility in water 1g / 0.9 ml water
Chemical Safety
Viscosity
Concentrated (50%) aqueous solutions of sodium hydroxide have a characteristic viscosity, 78 mPa·s, that is much greater than that of water (1.0 mPa·s) and near that of olive oil (85 mPa·s) at room temperature. The viscosity of aqueous NaOH, as with any liquid chemical, is inversely related to its service temperature, i.e., its viscosity decreases as temperature increases, and vice versa. The viscosity of sodium hydroxide solutions plays a direct role in its application as well as its storage
Chemical Properties of Caustic Soda
Reaction With Acids
Sodium hydroxide reacts with protic acids to produce water and the corresponding salts. For example, when sodium hydroxide reacts with hydrochloric acid, sodium chloride is formed:
NaOH(aq) + HCl(aq) -> NaCl(aq) +H2O
In general, such neutralization reactions are represented by one simple net ionic equation:
OH- (aq) + H+(aq) -> H2O
This type of reaction with a strong acid releases heat, and hence is exothermic. Such acid-base reactions can also be used for titrations. However, sodium hydroxide is not used as a primary standard because it is hygroscopic and absorbs carbon dioxide from air.
Reaction With Acidic Oxides
Sodium hydroxide also reacts with acidic oxides, such as sulfur dioxide. Such reactions are often used to “scrub” harmful acidic gases (like SO2 and H2S) produced in the burning of coal and thus prevent their release into the atmosphere. For example,
2NaOH + SO2 -> Na2SO3 + H2O
Reaction with Metals and Oxides
Glass reacts slowly with aqueous sodium hydroxide solutions at ambient temperatures to form soluble silicates. Because of this, glass joints and stopcocks exposed to sodium hydroxide have a tendency to “freeze”. Flasks and glass-lined chemical reactors are damaged by long exposure to hot sodium hydroxide, which also frosts the glass. Sodium hydroxide does not attack iron at room temperatures, since iron does not have amphoteric properties (i.e., it only dissolves in acid, not base). Nevertheless, at high temperatures (e.g. above 500 °C), iron can react endothermically with sodium hydroxide to form iron(III) oxide, sodium metal, and hydrogen gas. This is due to the lower enthalpy of formation of iron(III) oxide (−824.2kJ/mol compared to sodium hydroxide (-500kJ/mol), thus the reaction is thermodynamically favorable, although its endothermic nature indicates non-spontaneity. Consider the following reaction between molten sodium hydroxide and finely divided iron filings:
4Fe + 6NaOH -> 2Fe2O3 + 6Na + 3H2
A few transition metals, however, may react vigorously with sodium hydroxide.
Different Grades of Caustic Soda
Caustic soda is provided in the market under various grades and qualities, each designed for a particular application. Understanding that this substance’s degrees hold specific properties and unique purities obtained by following different production processes is vital. In the industrial setting, sodium hydroxide is made as a 50% solution using other electrolytic processes. In this procedure, chlorine is also created. The water is evaporated from this solution to produce solid sodium hydroxide. For sale, the most popular forms of solid sodium hydroxide are flakes, prills, and cast blocks.
Solutions and grades of caustic soda are often created electrolytically along with chlorine as co-products. Typically, one of three technologies—Mercury cells, membrane cells, or diaphragm cells—is used for this. Given the importance of understanding the purity of the caustic soda produced and the level of impurities anticipated, a summary of each method is provided below. Before that, it is vital to know that it is fair to predict impurities like unreacted salt (or NaCl), sodium chlorates (or NaClO3), sodium carbonates (or Na2CO3), and sodium sulfates because the starting material uses sodium chloride (or NaCl) (or Na2SO4). Varied tank or line products will contain different levels of chlorides depending on how the caustic soda is made. It is significant because there is a chance that chloride stress corrosion will develop over time, especially in the vicinity of stainless steel welds in lines or tanks where high chloride concentrations may develop as a result of frequent cleaning cycles.
Mercury Cell or Rayon Grade
This production method for Caustic soda uses mercury as the cathode for the electrolytic reaction. There is no net consumption of mercury in the reaction, and this process produces the highest purity caustic soda (lowest level of contaminants) commercially available. Typically, 50 – 52% by weight NaOH can be directly generated from the mercury cell without the need for further evaporation. Mercury cell produced caustic soda is typically referred to as Mercury Cell Grade or Rayon Grade.
Diaphragm Cell Grade
This process for producing Caustic soda has traditionally used asbestos (now uses safer, alternative substitutes) to separate the co-products, caustic soda and chlorine. This method typically provides a weak “cell liquor” (typically 12-14% by weight) and, therefore, subsequent evaporation is used (utilizing a three or four effect evaporation process) so that a reasonable final concentration of caustic soda, i.e., circa 50% is reached. This process produces the lowest quality electrochemical caustic soda solutions. This grade of caustic soda is referred to as Diaphragm Cell Grade, Commercial Grade, Technical Grade, and sometimes Technical Diaphragm Grade. An additional grade from this process, whereby evaporation is further used to reduce the salt concentration is called “Purified Grade.”
Membrane Cell Grade
This process for producing caustic soda uses selective membranes designed to separate chlorine and sodium ions. These membranes allow migration of sodium ions across the membrane keeping the chlorine gas and brine on the other side of the membrane. The sodium ions react with water in the mercury cell to produce the caustic soda which is typically 33-35% by weight. Evaporation is used, similar to the diaphragm method, to push the caustic concentration to around 50% by weight. It should be noted that small quantities of salt can migrate across the membrane elevating the final level of “contamination.” This caustic is typically referred to as Membrane Grade.
Caustic Soda Production Process
Chlorine does not exist in its elemental (gas) form in nature (as Cl2). Caustic soda is created as a liquid (often as NaOH). These are made by running brine through an electrical current (common salt dissolved in water). This procedure, known as electrolysis, has been practiced for more than 120 years. Briefly speaking, three essential components must be used to create elemental chlorine: salt, electricity, and water. We obtain elemental chlorine (Cl2), caustic (typically sodium hydroxide or NaOH), and hydrogen from these three ingredients (H2). Due to the high reactivity of these three compounds, technologies have been developed to keep them separate. There are three leading technologies chemists usually employ to produce this substance; in the last section, we went into the detail of these methods and the outcomes that hold various purities and are introduced as different grades.
Caustic soda Applications
Sodium hydroxide is used to manufacture many everyday products, such as paper, aluminum, commercial drain and oven cleaners, and soap and detergents.
In Cleaning & Disinfectant Products
Sodium hydroxide is used to manufacture soaps and a variety of detergents used in homes and commercial applications. Chlorine bleach is produced by combining chlorine and sodium hydroxide. Drain cleaners that contain sodium hydroxide convert fats and grease that can clog pipes into soap, which dissolves in water.
In Tissue digestion
In a similar fashion, sodium hydroxide is used to digest tissues, as in a process that was used with farm animals at one time. This process involved placing a carcass into a sealed chamber, then adding a mixture of sodium hydroxide and water (which breaks the chemical bonds that keep the flesh intact). This eventually turns the body into a liquid with coffee-like appearance, and the only solid that remains are bone hulls, which could be crushed between one’s fingertips
In Pharmaceuticals & Medicine
Sodium hydroxide is used to help manufacture a variety of medicines and pharmaceutical products, from common pain relievers like aspirin, to anticoagulants that can help to prevent blood clots, to cholesterol-reducing medications.
In Energy Industry
In the energy sector, sodium hydroxide is used in fuel cell production. Fuel cells work like batteries to cleanly and efficiently produce electricity for a range of applications, including transportation; materials handling; and stationary, portable and emergency backup power applications. Epoxy resins, manufactured with sodium hydroxide, are used in wind turbines.
In Water Treatment
Municipal water treatment facilities use sodium hydroxide to control water acidity and to help remove heavy metals from water. Sodium hydroxide is also used to produce sodium hypochlorite, a water disinfectant.
In Food Production
Food uses of sodium hydroxide include washing or chemical peeling of fruits and vegetables, chocolate and cocoa processing, caramel coloring production, poultry scalding, soft drink processing, and thickening ice cream. Sodium hydroxide is used in several food processing applications, such as curing foods like olives or helping to brown Bavarian-style pretzels, giving them their characteristic crunch. Sodium hydroxide is used to remove skins from tomatoes, potatoes and other fruits and vegetables for canning and also as an ingredient in food preservatives that help prevent mold and bacteria from growing in food.
In Wood & Paper Products
In many paper making processes, wood is treated with a solution containing sodium sulfide and sodium hydroxide. This helps dissolve most of the unwanted material in the wood, leaving relatively pure cellulose, which forms the basis of paper. In the paper recycling process, sodium hydroxide is used to separate the ink from the paper fibers allowing the paper fibers to be reused again.
Sodium hydroxide is also used to refine raw materials for wood products such as cabinets and furniture and in wood bleaching and cleaning.
In Aluminum Ore Processing
Sodium hydroxide is used to extract alumina from naturally occurring minerals. Alumina is used to make aluminum and a variety of products including foil, cans, kitchen utensils, beer kegs and airplane parts. In building and construction, aluminum is used in materials that enable building facades and window frames.
In Dissolving amphoteric metals and compounds
Strong bases attack aluminum. Sodium hydroxide reacts with aluminum and water to release hydrogen gas. The aluminum takes the oxygen atom from sodium hydroxide, which in turn takes the oxygen atom from the water, and releases the two hydrogen atoms, the reaction thus produces hydrogen gas and sodium aluminate. In this reaction, sodium hydroxide acts as an agent to make the solution alkaline, which aluminum can dissolve in.
2Al + 2NaOH + 2H2O -> 2NaAlO2 + 3H
Sodium aluminate is an inorganic chemical that is used as an effective source of aluminum hydroxide for many industrial and technical applications. Pure sodium aluminate (anhydrous) is a white crystalline solid having a formula variously given as naAlo2 ,NaAl(oh)4 (hydrated),Na2.Al2O3 , orNa2Al2O4 . Formation of Sodium tetrahydroxoaluminate (III) or hydrated sodium aluminate is given by
2Al + 2NaOH + 6H2O -> 2NaAl(OH)4 + 3 H2
This reaction can be useful in etching, removing anodizing, or converting a polished surface to a satin-like finish, but without further passivation such as anodizing or alodining the surface may become degraded, either under normal use or in severe atmospheric conditions.
In the Bayer process, sodium hydroxide is used in the refining of alumina containing ores (bauxite) to produce alumina (aluminum oxide) which is the raw material used to produce aluminum metal via the electrolytic Hall-Héroult process. Since the alumina is amphoteric, it dissolves in the sodium hydroxide, leaving impurities less soluble at high pH such as iron oxides behind in the form of a highly alkaline red mud
In Other Sectors of Industry
Sodium hydroxide is used in many other industrial and manufacturing processes. It is used to manufacture rayon, spandex, explosives, epoxy resins, paints, glass and ceramics. It is also used in the textile industry to make dyes, process cotton fabric and in laundering and bleaching, as well as in metal cleaning and processing, oxide coating, electroplating and electrolytic extracting.
About JAM Group’s Caustic Soda
In the last section, we explored caustic soda, and by now, we knew that various industries utilize this substance as a crucial ingredient to present a high-quality outcome. Accordingly, it is obliging to get to know a perfect caustic soda manufacturer and exporter you can rely on to supply various grades of this multipurpose substance. JAM Group Co is a devoted manufacturer with more than a dozen chemical compounds, including several grades of caustic soda. JAM Group’s products are among the most popular products in the market due to their purity and high property.
When it comes to choosing JAM Group, customers can enjoy several options. They can decide on their desired purity and then go for their intended way of packing the product and shipping. Our experts at JAM Group follow international routines at the logistics unit to ensure you a flawless exportation process. Still, you can customize the packing methods and order your intended weight. In this case, we strongly suggest contacting our specialists in JAM Group’s office in Germany. You can find out more about this company by navigating to About Us.
Conclusion
Lye and caustic soda are other names for sodium hydroxide, an inorganic substance with NaOH formula. It has a variety of qualities, which allows it to work in a variety of industries. It serves as a drain cleaner and is utilized in producing pulp and paper, textiles, drinking water, soaps, and detergents. In 2004, roughly 60 million tons of sodium hydroxide were produced globally, compared to 51 million tons in demand. The chloralkali process results in the production of sodium hydroxide, along with chlorine and hydrogen. One of three methods—Mercury cell, diaphragm cell, or membrane cell processes—is commonly used. Each method will lead to a unique grade of Sodium hydroxide that may be utilized in a specific industry.
