Fertilizer History: The Haber-Bosch Process
Nitrogen is the single most important plant nutrient in today’s commercial fertilizers. It’s essential for making sure plants are healthy as they grow and nutritious to eat after they’re harvested. But today in agriculture, we take for granted N’s ready availability.
More than 175 years ago, a scientific debate was raging in Europe over the importance of N for the growth of plants. British scientists Bennet Lawes and Joseph Henry Gilbert settled the debate when they published research showing that the addition of N fertilizers increased wheat yields in England. Fifty years later, industrialized nations were challenged with how to feed their growing populations and Great Britain was importing the majority of its wheat. In 1898, William Crooks, president for the British Association for the Advancement of Science, called for chemistry researchers to find solutions to aid in the manufacture of N fertilizers to help solve the coming food crisis.
The solution soon came from German scientist Fritz Haber, who discovered in 1909 that the chemical reaction of N and hydrogen-produced ammonia—the main component in nitrogen-based fertilizers. In July of that same year, Germany’s largest chemical company, BASF, funded German chemist and engineer, Carl Bosch, to develop commercial scale production of ammonia.
The process wasn’t easy, however. Ammonia production depended on high temperatures and pressures, as discovered by Haber. Much of the necessary machinery had to be invented to handle the extreme production conditions. Bosch’s machine, unveiled in 1914, stood 26 feet tall and could produce 198 pounds of ammonia per hour.
Soon after the plant was built, World War I began, and the new plant was used to manufacture material for explosives. Following the war’s end, Germany attempted to keep the Haber-Bosch process a secret. During negotiations at Versailles, however, Bosch, who was a member of the German negotiating team, offered the French government the technical details they would need to build their own Haber-Bosch plant. The French began producing ammonia in the early 1920s, followed soon by the British and Americans.
Haber’s and Bosch’s contributions to ammonia production were honored with two Nobel Prizes. Haber was presented with the Nobel Prize in 1920 for his research that unlocked the ammonia production process. In 1932, Bosch and Frederick Bergius received the Nobel Prize for their contributions to the invention and development of chemical high pressure methods. Today, a modern ammonia production facility produces approximately 1,000 tons of ammonia per day.
These advances in ammonia production have significantly increased yields of food and feed grain crops. In just 70 years, there’s been a six-fold increase in U.S. corn yields, thanks to the abundance of available nitrogen.
The world simply cannot do without N fertilizer, and the contributions made by Fritz Haber and Carl Bosch. Through fertilizer, we have the means to ensure that each growing season’s crops have the nutrients necessary to yield nutritious, bountiful foods for an increasing global population.