What is Lithium Bromide Solution
Lithium bromide aqueous solution is obtained by mixing lithium bromide (LiBr) with water. Lithium bromide is also a kind of salt chemically, and its solution has a strong ability to absorb water vapor, so it is used as an absorbent and water is used as a refrigerant in an absorption refrigerator.
Lithium bromide is a colorless granular crystal. Lithium and bromine belong to the alkali and halogen group elements respectively, and their chemical properties are similar to those of table salt. They are stable in nature and will not deteriorate, decompose or volatilize in the atmosphere. The main physical properties of anhydrous lithium bromide are as follows: Molecular formula LiBi Composition Lithium 7.99 percent , Bromine 92.01 percent Molecular weight 86.858 Melting point 549'C Specific gravity 3.464 (at 25 degrees Celsius) Boiling point 1265 degrees Celsius.
Lithium bromide has strong absorption and is easily soluble in water. Lithium bromide solution dissolved in water has the following characteristics:
(1) It has strong hygroscopicity. It can be seen from the values obtained by the experiment that the lithium bromide aqueous solution has a very low partial pressure of water vapor, which is much smaller than the saturated vapor pressure of single water at the same temperature. The temperature of water to reach such a low saturated vapor pressure is very low. Within a certain range of solution concentration, the higher the concentration of the solution, the lower the partial pressure of water vapor and the stronger its hygroscopic ability, even if the temperature remains unchanged.
(2) The lithium bromide aqueous solution is easy to crystallize, and the crystallization temperature has a great relationship with the concentration. When the concentration is slightly different, the crystallization temperature varies greatly. This situation is prominent when the concentration is 65 percent . Preventing crystallization is an important issue that must be paid attention to in the design and operation of lithium bromide absorption chillers. The test shows that the crystallization temperature is 46.5 degree when the solution concentration is 65 percent , and the temperature is 64 degree when the solution concentration is 66 percent . In order to prevent crystallization, the solution concentration should not exceed 66 percent in design.
(3) Corrosive. Lithium bromide aqueous solution is extremely corrosive to general metals, especially in the presence of air, due to the presence of oxygen in the air, carbon steel can rust up to 1 2mm within a few months. Therefore, isolating oxygen is the most effective anti-corrosion measure. In addition, adding a corrosion inhibitor to the solution can effectively inhibit the corrosion of the metal material by the lithium bromide solution. Tests show that lithium chromate is a good corrosion inhibitor. The concentration of lithium chromate in the solution has a good corrosion inhibition effect in the range of 0..126 to 0.3 percent .
Lithium bromide solution has the characteristics of non-toxicity, salty taste and no harm to human body. Due to its strong water absorption, droplets feel warm on the skin, but should be washed immediately if splashed into the eyes to prevent inflammation and blindness.
