Every year, about one and a half million people die in the world due to lack of clean water suitable for drinking. This happens due to the fact that more than 80% of all water resources are spent on irrigating soils in the desert regions of our planet. Scientists from a company developing hydrophobic materials have invented a sand cover to reduce its need for water and irrigation. African countries, as well as the states of the Middle East, suffer most from the lack of fresh drinking water, which is why hydrophobic sand was invented in the United Arab Emirates, however, with the support of German specialists.
To understand its nature, it is necessary to study the definition of hydrophobicity.
What is hydrophobicity and how does it differ from hydrophilicity?
These two interrelated concepts are applicable to any substances and materials. They are responsible for how easily or not they come into contact with water. On materials with a hydrophilic surface, a drop of water spreads completely and is absorbed. Such bodies include carbonates, silicates, sulfates, clays and silicate glasses. The hydrophobic surface repels a drop of water and prevents it from penetrating inside. All metals, paraffins, fats, waxes and some types of plastics have this property. Hydrophobicity is a low degree of hydrophilicity. In the textile industry, fabrics are hydrophilized to make them more dyed, and their hydrophobization helps to make them waterproof.
How to suppress hydrophilic properties in sand?
Even without delving too deeply into the physics of substances, it is clear that sand perfectly passes and absorbs water. But thanks to modern nanotechnology, scientists are working wonders by changing the initial properties of materials. To get hydrophobic sand, they had to treat each grain of sand with a special solution, the secrets of which are not disclosed. Such sand retains its properties for 30 years. So far, these events are taking place at the level of experiments, but the company is ready to work on an industrial scale. It takes about 40 seconds to process one grain of sand, but producers have the resources to produce 3,000 tons of hydrophobic sand daily.
How will sand reduce global water consumption?
Scientists suggest using hydrophobic sand as a waterproof separating layer between fertile soil,which plants are grown, and all other soil strata. This layer will reduce the number of waterings per day from 5 times to one, because the water will not go to depth, but will nourish the roots. Scientists have even ventured into a bold experiment to grow rice in arid areas, but no concrete results yet.
Sand with hydrophobic properties will also find great use in construction when building foundations, in particular in regions with high groundwater levels.
How to make hydrophobic sand yourself?
In order to place a handful of sand in water and then extract it dry, it is necessary to pre-treat, usually with silicone polymers. Most curious minds are haunted by the question: is it possible to make hydrophobic sand at home? Of course, it is possible, but not of such high quality and retaining its properties for a long time. There is one way that some people show the public as a trick. It is necessary to place clean sand in a red-hot oven, let it warm up well and dry there. Then take it out and treat it with water-repellent clothing sprays. You can buy these at any sports equipment store. After these manipulations, you can repeatedly place and remove the sand from the water tank completely dry.
