Category: Chemistry

Refractory materials

Refractory materials

Refractory materials

05/31/17

“Are there materials that retain their strength at exceedingly high temperatures?”

 

For processes such as nuclear power generation or incinerators, materials must be able to withstand heavy loads. However, the high temperatures that they operate at often destroy the useful properties of most materials. So are there materials that can withstand high temperatures? Well, after many years of hard work spent in research, Materials Engineers and Scientists have been able to classify such materials as refractory materials. Refractory materials can be divided into two types, acidic refractories with SiO2 content more than 93% used for their erosion resistance, and basic refractories for higher thermal resistance

Fractional distillation

Fractional distillation

Fractional distillation

05/28/17

“How can we have distillation for materials with more than two substances?”

 

Distillation is the process of separating two substances using the science of evaporation and condensation in regard to different boiling points. However, how can we make this process happen for materials such as crude oil which are composed of many different substances? Well, let’s use our engineering mindset to find out. Let’s start out with a simple test tube. In this test tube, let’s also have another smaller tube at the midsection leading to a stationary beaker. Now let have the bottom portion of the main tube be immersed in a hot fluid. When we dispose a material into the tube, the hot fluid will heat the material until one of the substances evaporates. The gas from the evaporated substance will rise and move through the tube, eventually reaching the midsection tube, cooling and condensing into a liquid form in the beaker. Once all of this substance has been removed, we can swap out the old stationary beaker for a new one, replace the hot liquid with a bunsen burner, and repeat the process. This procedure is known as fractional distillation and is commonly employed for separating substances with numerous hydrocarbons.

Cross-linking

Cross-linking

Cross-linking

05/20/17

“What happens when polymer chains link together?”
Polymers are famous for their absolutely long chains. However what happens when these chains link together? Well, let’s use our scientific mindsets to find out. If we look carefully, then we will observe that the density of the materials will go down (since now all of its composing elements will no longer be able to be squeezed together so easily) but the strength will increase since the there are now three-dimensional impediments to dislocations.

Elastomers

Elastomers

Elastomers

05/19/17

“How can we have flexible polymers?”
Polymers are widely utilized in a swath of industries for their malleable properties. But is it possible to make such things flexible? Well, let’s use our scientific mindset to find out. Polymer molecules are often arranged in a disordered manner due to the second law of thermodynamics. However, when pulled upon, some of these materials can actually become more ordered and will revert to their original shape once the force is removed, giving them an elastic property. These materials are known as elastomers,and are commonly used for flexible materials such as rubber. Elastomers are usually thermosets, have a low young’s modulus, and a higher failure strain.

Composites

Composites

Composites

05/18/17

“What happens when two materials of vastly different properties come together?”

 

When working with plastics, we often need to enhance their properties somehow. So it would be logical if we could think of a scientific way that we can engineer this? Since such a material would be composed of more than 2 different discrete materials, it will have two different layers, one being a reinforcement or fiber that provides the material with strength, and the other one is a matrix that binds the material together and insulates it from the external world. This type of material is known as a composite and is used for all sorts of applications, ranging from the cement that we use to kevlar armor to the space shields used by NASA!

Thermosetting polymers

Thermosetting polymers

Thermosetting polymers

05/16/17

“Can certain plastics become harder with heat?”
Thermoplastic materials are widely used for their behavioral effects to induced heat. However, is it possible that some materials might become harder with temperature in an irreversible process? Well, let’s use our scientific mindset to find out. We know that when polymers become cross-linked, they become harder and tougher. So it would follow that when heated, they would be stronger when compared to a non-cross-linked material. What more, because these polymer chains are bonded to each other, they will not change shape after reheating! Thermosetting polymers have applications to be found everywhere, from latex gloves to erasers to bicycle tires.

Direct Air Capture

Direct Air Capture

Direct Air Capture

05/04/17

“How can we capture carbon dioxide directly from the air?”
There is a global problem. Carbon dioxide emissions from industrialization have polluted the atmosphere to the point where a worldwide rise in temperatures has been induced. However, would it be possible if we could use our engineering mindset to take CO2 out of the atmosphere? Well, let’s start by using a little bit of knowledge of basic science. There are chemicals that are able to capture CO2 through a “sticking” process while leaving other atmospheric molecules such as nitrogen and hydrogen unabated, therefore creating a barrier. And this mechanism can then be heated such that the CO2 molecules are free from the material, allowing new CO2 to come in. So what if we were to take a pool of industrial fans, stack them up in rows and columns, place a CO2 absorbing material behind it and have them suck up all of the air? This method is known as Direct Air Capture and can be used to help in the fight against global warming

Exhaust gas

Exhaust gas

Exhaust gas

04/22/17

“Why do diesel engines vehicles cause pollution?”

 

Every day, you probably hear about how the levels of greenhouse gas concentration in the atmosphere are growing exponentially, and how much of that derives from the use of petroleum vehicles. However, why do such machines cause so much harm? Well, let’s use our scientific mindset to figure this out. Upon analysis, one would be able to obtain that the exhaust gas emitted by vehicles are composed of carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen oxides, and hydrocarbons. These pollutants are potent greenhouse gasses, and can not only impinge upon the health of the atmosphere but the health of human society through the instigation of smog and other health hazards.

Desalination plants

Desalination plants

Desalination plants

04/21/17

“How can we make saltwater drinkable for humans?”

 

Humanity is running into a problem. With each year our water supplies are getting lower and lower. Soon enough, we may not be able to provide ourselves with one of the most basic components of life.

 

But does it have to be this way?
If we apply our engineering mindsets, then we can devise a method for water purification to sustain our livelihoods. To begin, let’s start out with some simple chemistry. 96% of the water on this planet is stored in oceans as salinated water. And because of its salty nature, by default, it is unsafe for human consumption. However, we must take one more fact into consideration, that the evaporation point of liquid water is lower than that of salt. So what if we used some simple logic and create a device that would heat salt water up until the point of evaporation, move it over into another container, and then condense it into drinkable water? Well, this is the fundamental idea behind a system which engineers have termed desalination plants, and are used to treat saltwater around the world. One downside of traditional desalination plants is the vast amount of energy required to heat up the water, taking around 5 kWh for a cubic meter of just fresh water!