Sodium Hydroxide, commonly known as lye or caustic soda, is an inorganic compound with a strong metallic base. Caustic soda is available in a number of forms including granules, pellets, flakes, and solutions prepared with different concentrations.
Sodium Hydroxide is widely used in a colorful spectrum of industrial and chemical processes and as of 2004, had a worldwide demand of over 51 million tonnes.
What industries and applications handle Sodium Hydroxide (Caustic)?
Sodium Hydroxide is widely used as a strong base to dissolve in water and combine with an acid to create a salt. It has many use cases for PH regulation and the manufacturing process of different sodium salts.
In broader terms, it is used in many scenarios where the goal is to increase the alkalinity of a combination to neutralize an acid.
Some of the specific use cases of Sodium Hydroxide include:
- Paper industry: One of the key steps in the process of creating paper out of wood is chemical pulping. This step, and other steps involved in the process of making paper require strong alkaline environments of above 10.5 PH.
- Food industry: The food industry widely uses Sodium Hydroxide for chemical peeling or washing of vegetables and fruits. Cocoa beans are also processed with caustic soda. Some methods for softening olives also involve sodium hydroxide.
- Cleaning agent: Sodium Hydroxide can easily remove fats, oils, grease and protein based compounds and therefore, is used widely as an industrial cleaning agent where it is commonly known as “caustic”. One of the typical methods of using sodium hydroxide is to heat it as a solution and then spray it with high pressure. Sodium hydroxide in the form of a thick liquid gel or dry crystal is also used in homes as a drain opener.
What are the properties of Sodium Hydroxide (Caustic) that will affect what pump and material you purchase?
Figure 1: Sodium Hydroxide Concentrations and Pump Materials
A single or collection of material/s may be rated for a higher temperature/s then the pump as a whole is capable of. It is important to contact a March representative to determine if the pump as a complete unit is suitable for the concentration and temperature of any chemical.
Caustic soda is a highly corrosive compound and is extremely reactive with some metals and alloys including aluminum and carbon steel.
Leak-free pumping is a particular concern when dealing with high concentration sodium hydroxide solutions. Caustic soda leaks not only cause severe injuries to personnel but can also damage the best equipment. To avoid that, a pump without mechanical seals, such as a mag drive model, is recommended.
What materials can best handle Sodium Hydroxide (Caustic)?
In normal cases where the concentration of sodium hydroxide is not very high most metals as well as polypropylene, PTFE, PVDF and EPDM can be used. In cases where caustic soda with very high concentrations are involved special synthetic materials and special alloys are required.
Choosing the right Sodium Hydroxide Chemical Pump
There are many parameters which should be taken into account when choosing the suitable pump for a particular use case. These parameters include but are not limited to compound concentration, working temperatures, gravity of the chemical, and the materials used in the pump itself. Here at March Pump, we exhibit a wide range of chemical industrial pumps that cover virtually any possible requirement.
For further information we encourage you to contact our friendly support team and our experts will be happy to help. Please give us a call or contact us online.