Some chemical reactions face a similar situation. They're almost impossible to carry out without outside help, but like a roommate pushing a hand at painting the walls, the catalyst also makes everything a lot easier. In fact, the real effect of the catalyst is to reduce the amount of energy required to initiate a reaction—it provides a new route for the reaction, so that the energy barrier to be overcome on the way is not so large.
Even better, the catalyst is not consumed in the reaction, so it is constantly helping out. With just a small amount in the human body, transition metals are often utilized by vitamins for their catalytic properties. For a long time, vitamin B2 was regarded as a mysterious factor ingested by the liver through consumption, so it is also called "liver factor", which can lead to anemia in humans or dogs. With the help of diamond ions, it is able to catalyze a number of reactions that are closely related to metabolism and the production of red blood cells. It was the first metalloenzyme to determine its structure by X-ray crystal diffraction.
Due to the extremely complex structure, the whole measurement process is full of hardships and bumps. The work was completed by Dorothy Crawford Hodgkin, for which he was awarded the Nobel Prize in Chemistry in 1964. Cytochrome oxidase is another enzyme that contains transition metals, and the copper it contains can help plants and animals obtain energy from food. The body only needs milligrams of B vitamins to function properly, so it needs very little cobalt (remember, they can be recycled). But if it is excessive, the human body will feel uncomfortable. When the old Australian lady's artificial hip joint was replaced with polyethylene and ceramic parts, she felt much more comfortable within a few weeks.
The excellent catalytic properties of transition metals are all-encompassing, not only in biochemical reactions. Nickel, a silver metal, for example, can be used not only to make coins and parts for high-speed engines, but also to catalyze a reaction that hardens grease. This type of reaction can add hydrogen atoms to human carbon-containing molecules, converting "unsaturated" molecules into saturated molecules. At the beginning of the 20th century, the French chemist Paul Sabatier discovered that metals such as nickel, diamond, iron, and copper could help hydrogenate unsaturated acetylene into ethane. Since then, he has experimented with the most efficient nickel-metal hydride carbonaceous compounds. In 1912, he was awarded the Nobel Prize for his work on "catalyzing hydrogenation reactions using ultrafine metal powders." Since then, the food industry has started using nickel as a catalyst to convert liquid vegetable oil into solid margarine. Kerui shortening became the first commodity to contain margarine. One disadvantage of nickel-catalyzed hydrogenation is that trans fats, which are by-products of partial hydrogenation, are produced during hydrogenation.
It can lead to health problems such as high cholesterol and heart disease. At the beginning of the 21st century, countries began to pay attention to this issue and required that food must be labeled with trans fat content. Today's Kerui shortening is no longer trans fat-free. Of course, not all catalysts are transition metals, and many other elements or compounds can also accelerate the reaction. However, the 2005 Nobel Prize in Chemistry was once again awarded to a class of reactions driven by metal catalysts: olefin metathesis. This reaction is extremely important for the plastics and pharmaceutical industries. And drilling is now also being used at the cutting edge of chemistry: stripping hydrogen from water to extract clean energy.