The legendary story of chemists-1990 On August 7th, a bust of white marble of Hou was completed in Nanjing Chemical Company to commemorate the famous chemist who made great contributions to the development of soda ash industry in the world and won great honor for China.
Soda soda, the chemical name is sodium carbonate, commonly known as soda. It is an important chemical product, widely used in making glass, soap, pulp, detergent and refining petroleum.
Soda can exist in nature, but its purity is low and its producing areas are scattered, which is far from meeting the needs of society.
1862, Sul, Belgium was the first to make soda ash by chemical method. The main raw materials he uses to make soda ash are salt and limestone. The basic method for manufacturing soda ash is to saturate the concentrated salt solution with ammonia water, and then the carbon dioxide generated by limestone calcination reacts with the ammoniated saturated brine to generate ammonium bicarbonate. Ammonium bicarbonate further reacts with salt to obtain sodium bicarbonate and by-product ammonium chloride. Sodium bicarbonate has low solubility. After filtration and separation, soda ash is obtained, and carbon dioxide is released after heating. Carbon dioxide can be reused. Ammonium chloride can react with lime milk to produce calcium chloride and ammonia, which can be collected and recycled.
This process is called Sulvi process, which has monopolized the world soda industry for more than 70 years. The method has the advantages that carbon dioxide and ammonia gas generated by the reaction can be recycled, the process is simple, and raw materials are easily available. But it also has two fatal shortcomings: first, the utilization rate of salt is too low, only about 70%; Second, a large amount of calcium chloride generated by the reaction between ammonium chloride and lime milk is of little use, can not be treated, and even causes environmental pollution. At that time, although chemists in many countries tried to improve this method, they all failed.
192 1 year 10, Hou returned from the United States with the ambition of developing the chemical industry of the motherland, and first built an alkali plant in Tanggu. At that time, it was conceivable that international capital groups monopolized alkali production technology and wanted to develop their own national alkali production industry. Hou eliminated all kinds of resistance, went deep into the fields, personally practiced, drilled and developed alkali production technology, and constantly solved equipment and technical problems. Finally, an alkali plant was built in 1924. The factory produces 180 tons of soda ash every day. The completion of Tanggu Soda Plant has broken through the international monopoly of Sulvi Group in technology and defeated the crowding out of Park Neimen Company in operation. Made in this factory? Red triangle? Spring cocoon, 1925, won the gold medal of the Philadelphia World Expo, winning glory for the motherland. More importantly, through the establishment of China Soda Factory, Hou realized the complete mastery and mastery of soda production technology, which laid the foundation for the innovation of soda production technology. He also published the monograph "Making Alkali" in 1932, which introduced Sulvi's method of making alkali completely for the first time. This book, which is proud of the Chinese nation, immediately caused a sensation in the chemical industry all over the world and was regarded as the first monograph on soda production by the world.
There is no end to science and technology, and the needs of society and production are constantly opening the way for the advancement of science and technology. After the outbreak of War of Resistance against Japanese Aggression, Tianjin fell. 1938, Hou was responsible for establishing a new soda plant in Wangtongqiao, Sichuan, Chinese mainland.
However, the raw material used in Tanggu Alkali Factory is sea salt, and well salt is needed to build a factory in Sichuan. The concentration of well salt brine is low, and the composition is slightly different, so it is not suitable to use Sulvi method again. In addition, a large amount of calcium chloride produced by Sulvi method can only be piled up as waste, which forces Hou to explore new ways. At this time, Germany invented a production method of tea soda ash. Although the technology is not mature, ammonium amide can be produced by using the waste liquid from soda production, which is a great inspiration for Hou. Hou also went to Germany to discuss the purchase of patents, but the manufacturers were not allowed to make field visits, and the conditions for purchasing patents were extremely harsh, so Hou made up his mind to take the road of innovation.
In order to reform Solvay pure alkali process and create its own new process, Hou overcame various difficulties and set up a laboratory in Hong Kong. Through more than 500 tests, more than 2000 samples were analyzed and tested. Aiming at the shortcomings of Solvay pure alkali process, a new production process was conceived and designed. In order to realize this law and form productive forces, he also made concessions in new york and Shanghai? Island? The pilot test was carried out, and finally all the innovations of the new alkali production process were successfully completed in 1940.
The new alkali production method created by Hou is to combine alkali production and synthetic ammonia into one, which is commonly called co-production and production reduction. This method not only retains the advantages of Sulvi method, but also overcomes its disadvantages, making the alkali production method more perfect. His main contribution is that after sodium bicarbonate is crystallized and filtered, salt is added to the remaining mother liquor containing ammonium chloride instead of lime milk. In this way, because a large number of chloride ions are added to the solution, ammonium chloride will precipitate out, and the remaining sodium ions can repeat the previous reaction to generate soda ash. In this way, soda ash and ammonium chloride (fertilizer) can be obtained at the same time as long as salt is continuously added to the mother liquor. Using this method to produce soda ash, not only the utilization rate of raw salt reaches above 96%, but also the whole production can be carried out continuously; In addition, it also has a series of advantages such as saving lime and simple equipment.
Because of Hou's outstanding contribution to the manufacture of soda ash, this method he invented was named 194 1? Hou Shi soda ash process? , and has been widely praised and highly praised by the chemical community at home and abroad.
? Hou Shi soda ash process? This is an invention named after China people. In our country, being bullied by imperialism and being scolded by others? Sick man of East Asia? At that time, the name of a China person will shine brilliantly on the stage of world science, pushing the history of world soda science to a new stage, fully demonstrating the wisdom and strength of the Chinese nation.
The Legend of the Chemist Part II Carl? Sholema 1834 was born on September 30th, 1934 in a family of handicraft workers in darmstadt, the German Black Forest. Father John is a poor carpenter and mother Lott is a simple housewife. They have nine children, and Carl is the oldest. 1850, Carl received an education in a vocational school in this city, but in 1853, he returned to his family and dropped out of school. He likes chemistry very much, so he went to a drugstore as an apprentice. Because he was diligent and studious, he soon became a pharmacist's right-hand man. 1856, he came to a pharmacy in Heidelberg as a dispensing assistant. In Heidelberg University, Benson, a famous chemist, is giving a lecture on chemistry. I tried my best to listen to Benson's speech. Benson's exquisite experimental demonstration and vivid report made Laima yearn for chemistry more, and made up his mind from then on. Be a chemist.
1859, he only lived on the money he saved, and entered the chemistry department of Giessen University, which was presided over by the famous chemist Justus von Liebig. This was the holy land that young chemists all over the world yearned for at that time. Because of lack of tuition, Laima Jr. dropped out of school after only one semester. Fortunately, in this semester, due to his efforts, he completed the course of analytical chemistry as the basis of the experiment. Through study and training, he basically mastered the skills of chemical experiments. At the same time, during this semester, he also listened to the course of chemical history taught by Professor Copp, a famous chemical historian, and initially cultivated his interest in the history of science. Dropout and unemployment did not affect Laima's pursuit of chemical science. At this time, it happened that Roscoe, a chemistry professor at Owens College in Manchester, England, wanted a personal experimental assistant. When Laima Jr. heard the news, he immediately rushed to Britain, which is far away from the motherland, and came to this industrial city in Britain. After hard work, he finally became Roscoe's experimental assistant. He is very satisfied here. On the one hand, we can continue to study chemistry related courses, on the other hand, we can carry out more independent chemical experiments. From then on, Laima Jr. finally realized his long-cherished wish and stepped into the door of chemical research. He taught himself and studied at the same time, and soon made a lot of achievements.
187 1 was elected as a member of the Royal Society, and 1874 became the first professor of organic chemistry at Owens College. He lived in England for more than 30 years until his death in 1892.
The development of plastics can be traced back to the middle of 19. At that time, in order to meet the needs of the booming textile industry in Britain. Chemists mix different chemicals together, hoping to make bleach and dyes. Chemists especially like coal tar, which is a curd-like waste condensed in the chimneys of factories fueled by natural gas.
Willaim henley Platinum, a laboratory assistant at the Royal Institute of Chemistry in London, was one of the people who carried out this experiment. One day, when platinum wiped the chemical reagent on the experimental platform, it was found that the rag was dyed into a rare lavender at that time. This accidental discovery made platinum enter the printing and dyeing industry and eventually became a millionaire.
Although the discovery of platinum is not plastic, this accidental discovery is of great significance because it shows that man-made compounds can be obtained by controlling natural organic matter. Manufacturers have realized many natural materials, such as wood, amber, rubber, glass and so on. Either it is too scarce, too expensive, or not flexible enough for mass production. Synthetic material is an ideal substitute, which can not only change shape under heat and pressure, but also keep shape after cooling.
Colin Williamson, founder of the Plastic History Society in London, said: At that time, people were faced with finding a cheap and easy-to-replace substitute. ?
After platinum, another Englishman, Alexander Parks, mixed chloroform with castor oil to get a substance as hard as animal antlers, which is the first artificial plastic. Parks hopes to use this artificial plastic to replace rubber which can not be widely used because of the cost of planting, harvesting and processing.
John wesley Hayet, a blacksmith from new york, tried to make billiards with artificial materials instead of ivory. Although he did not solve this problem, he found that mixing camphor with a certain amount of solvent can get a material that can change its shape after heating. Hite called this material celluloid. This new type of plastic has the characteristics of mass production by machines and unskilled workers. It brings a strong and elastic transparent material to the film industry, which can project images onto the wall.
Celuluo also promoted the great development of the family record industry, eventually replacing the early cylindrical records. Later plastics can be used to make vinyl records and cassette tapes; Finally, the CD is made of polycarbonate.
Celluloid makes photography a kind of activity with a broad market. Before George Huysmans invented celluloid, photography was an expensive and boring hobby, because photographers had to develop their own films. Hysmans came up with a new idea: the customer sent the finished film to his shop, and he developed the film for the customer. Celluloid is the first transparent material that can be made into thin sheets and rolled up and put into a camera.
About this time, Heismann met a young Belgian immigrant to Leo Baekeland. Baekeland discovered a kind of printing paper that is particularly sensitive to light. Hysmans bought Baekeland's invention at a high price of 750,000 dollars (equivalent to 2.5 million dollars today). With money, Baekeland built a laboratory. Phenolic plastics were invented in 1907.
This new material has achieved great success. Products made of phenolic plastics include telephones, insulated cables, buttons, airplane propellers and high-quality billiards.
Parker Pen Company makes all kinds of fountain pens with phenolic plastics. In order to prove the firmness of phenolic plastics, the company made a public demonstration and threw the pen from the tall building. Time magazine introduced the inventor of phenolic plastics and this technology with a cover article. Use materials thousands of times?
A few years later, DuPont's laboratory made another breakthrough unexpectedly: it made nylon, a product called rayon. 1930, Wallace carothers, a scientist working in DuPont's laboratory, immersed a heated glass rod in a long molecular organic compound and obtained a very elastic material. Although early clothes made of nylon would melt at the high temperature of the iron, its inventor carothers continued his research. About eight years later, DuPont introduced nylon.
Nylon has been widely used in this field. Parachutes and shoelaces are all made of nylon. But women are enthusiastic users of nylon. 1940 On May 5th, American women snapped up 5 million pairs of nylon stockings made by DuPont. Nylon stockings is in short supply, and some businessmen began to pretend to be nylon stockings with silk stockings.
But the success story of nylon has a tragic ending: its inventor carothers committed suicide by taking cyanide. Steven Fennichel, author of Plastics, said? After reading carothers's diary, I got the impression that carothers was very depressed that the materials he invented were used to produce women's socks. He is a scholar, which makes him feel unbearable. ? He thinks people will think that his main achievement is to invent a kind of? Ordinary commercial products? .
Dupont, on the other hand, is intoxicated by the fact that its products are widely loved by people. During the war, the British discovered many uses of plastics in the military field. This discovery is also accidental. In an unrelated experiment, scientists in the laboratory of Royal Chemical Industry Company found a white waxy deposit at the bottom of the test tube. After testing, it is found that this material is an excellent insulating material. Its characteristics are different from glass, and radar waves can pass through it. Scientists call it polyethylene, and use it to build a shelter for radar stations to cope with wind and rain, so that radar can still catch enemy planes in rainy and foggy weather.
Williamson of the Plastic History Society said? Two factors promoted the invention of plastics. One factor is the desire to make money, and the other is war. ? However, it was the next few decades that made plastics really what Finnichel said? Synthetic material century? A symbol of. In the 1950s, household products such as food containers, kettles and soap boxes made of plastic appeared. Inflatable chairs appeared in the 1960s and 1970s, and environmentalists pointed out that plastics could not degrade by themselves. People's enthusiasm for plastic products has declined.
However, in the 1980s and 1990s, due to the huge demand for plastics in the automobile and computer manufacturing industries, the status of plastics was further consolidated. It is impossible to deny this ubiquitous ordinary substance. Fifty years ago, the world could only produce tens of thousands of tons of plastics every year; Today, the annual output of plastics in the world exceeds 654.38 billion tons. The annual output of plastics in the United States exceeds the sum of steel, aluminum and copper.