These are compounds in crystalline forms that contain water molecules within its structure or the lattice. They usually indicate a wider range of physical and chemical stabilities, the interaction between molecules in the same structure, and solubility at the specific temperature and perhaps can vary from the parent anhydrous compound or lattice (Sloan & Koh, 2007). Hydrates are used in the chemical industries where issues of solubility are applied probably during the last stages though to some extent may be a problem. The hydrated crystals thermodynamically show the lowest solubility in water, which is sometimes the biggest advantage and on the other hand unwanted properties. For example, the hydrates are capable of reducing the solubility to some lower value that is now not needed in the application. However, there has been the improvement to make the hydrate more soluble and hence fit for other industries. The compound is also used in the agricultural sectors especially the one with a lower solubility since the fertilizer is supposed to take some time to the plant before being dissolved.
Hydrates are salt that exists in the crystalline forms and has the water of crystallization within its structure which makes it hydrated. They usually possess different colors within its structure, and we cannot say that they have specific colors for all of them. One hydrate may differ from the same parent when the water content has been taken from its structure and will retain its normal or perhaps the original color when the water of crystallization has been replaced back to the lattice. For example, cobalt (ii) chloride hexahydrate has a pink color due to the presence of the water of crystallization (Giavarini & Hester, 2011). When the water content is removed from its structure, the crystal color changes to blue, and it’s now called anhydrous due to the absence of the water of crystallization. The crystals are in different shapes and are held together by covalent and molecular bonds within the lattice and thereby making the structure strong and difficult to break.
Most of the hydrates have the ability to return to its original states when subjected to different conditions and thereby it can be considered to be a reversible reaction, this property makes it possible to be used in the agricultural sectors to retain the soil. The other property is the fact that most of the hydrated have a slow solubility with water. This means that when you take a hydrated salt and put in a jar of water and then stir up, it will sometimes take to dissolve all the crystals unless some external conditions like heat and others are involved. This property always creates a problem for some industries that had to come up with a means to make the crystal more soluble especially to water. Moreover, when the crystal is heated directly will lose it structure or perhaps its shape. The water of crystallization is the one who is responsible for the coloring effects in most hydrates though to some extent and not in all hydrates (Belosludov & Kudoh, 2007).
Condition for the formation of hydrates
The formation depends on the following conditions; the temperature, pressure and the gas compositions are all needed in some quantities to make the formation efficient. The amount of water that is required for the hydrate formation is a very important variable required for the process. The amount of water to gas ratio do vary depending on the amount and the composition of the pressure and the natural gas that is available for use. Ideally, the ratio of water to the natural gas is 6:1, however, to get a more yield of the hydrate the addition of pressure and the water may be considered for maximum result. However, the natural gas hydrates are like ice and are formed when the mixture comprising of water molecules and the natural gas is subjected to conditions of low temperature and the high pressure (Lee & Ripmeester, 2005)
Problems in different industries
In the pharmaceutical and agrochemical sectors, both use hydrates to aid in the production process to make the products they desired. However, the nitrates used in the process sometimes become a problem to the production process at the end of the process. It is common that the hydrated crystals will tend to dissolve slowly in water unless subjected to some external changes or forces like the heat and other like the pressure. For example in the active pharmaceutical ingredient, the hydrate formation within the process will have a possibility to reduce the solubility of the mixture to some low values, therefore, making the whole process ineffective and biased. The effect is felt even to the shift to using the anhydrous crystal which will automatically come into contact with water within the system and form a more stable component that will even be difficult to break and dissolve. However, to get rid and perhaps to help the situations, some initiative or measures are being taken to improve the solubility at this time or point to the industries (Lee & Ripmeester, 2005).
Belosludov, V. R., Subbotin, O. S., Krupskii, D. S., Belosludov, R. V., Kawazoe, Y., & Kudoh, J. I. (2007). Physical and chemical properties of gas hydrates: Theoretical aspects of energy storage application. Materials Transactions, 48(4), 704-710.
Giavarini, C., & Hester, K. (2011). Physical Properties of Hydrates. In Gas Hydrates (pp. 59-74). Springer London.
Lee, H., Lee, J. W., Park, J., Seo, Y. T., Zeng, H., Moudrakovski, I. L., … & Ripmeester, J. A. (2005). Tuning clathrate hydrates for hydrogen storage. Nature, 434(7034), 743-746.
Sloan Jr, E. D., & Koh, C. (2007). Clathrate hydrates of natural gasses. CRC Press.