How does carbon dioxide become plastic?
how does invisible carbon dioxide become white plastic? There are three technical difficulties to overcome here. The first problem was completed by Japanese scientists, while Meng Yuezhong solved the last two key problems
the first step is to separate carbon and oxygen atoms.
the constituent elements of carbon dioxide (CO2) are carbon and oxygen. Carbon is a necessary element to form organic substances (such as plastics). If carbon dioxide can be successfully combined with other compounds related to the quality of the tape, otherwise it will react with debugging substances, it can become the raw material of plastic making. This has been achieved by a Japanese scientist in 1969. For the first time, he used a catalyst called diethylzinc as the "fourth party" to disconnect the double bond between oxygen atoms and carbon atoms, and the carbon atoms "empathize" and release electrons to combine with other substances to form degradable plastics. Since then, scientists from all over the world have continuously discovered new catalysts
the second step is to expand the catalytic contact surface
scientists initially found that the catalyst cost was very high and could not be industrialized. In order to reduce costs, science in other words, we are not easily fooled. We strive to find a high-efficiency catalyst. At present, the maximum catalytic efficiency has reached 60-70 grams, but the catalyst price is higher. Meng Yuezhong took another path, no longer looking for new catalysts, but using existing catalysts to increase its catalytic efficiency. In chemistry, there is a proportional relationship, that is, the larger the contact surface between the catalyst and the object to be catalyzed, the more effective the catalytic reaction will be. This is like the radiator on the computer CPU we use. Even if the wind force of the fan is certain, the larger the surface area of heat dissipation, the faster the gas convection, and the better the cooling effect. Third, the "handshake" between molecules
to make the contact surface of the catalyst as large as possible, it is necessary to make its particles as small as possible. It is best to realize the "handshake" between molecules. Meng Yuezhong thought of a scientific principle that fluorine-containing compounds can be dissolved in liquid carbon dioxide. Carbon dioxide will become a fluid state under high pressure. If the catalyst is attached to this fluorocarbon and dissolved in carbon dioxide, the catalyst will also "shake hands" with the molecules that oxidize carbon when it works in a molecular state. Through this method, if the original surface area of a catalyst is 1 square centimeter, the surface area after treatment can be increased by at least 500 times, the catalytic efficiency has indeed increased by nearly 70 times, and the catalytic cost per ton of finished products is reduced to only 200 yuan
development history of carbon dioxide plasticization
in 1969, a scientist at Kyoto University in Japan first used diethylzinc as catalyst for plasticization, and each gram of catalyst can catalyze 0.13-0.7 grams of carbon dioxide
in 1991, a Chinese University used glycerol as a catalyst, but it could only catalyze 0.04 to 0.16 grams of carbon dioxide per gram, even lower than the level in 1969
in 1997, Tsinghua University in Taiwan used the above two materials combined with other materials to improve the catalytic efficiency to more than 2 grams
in 2000, a South Korean scientific research institution found that the catalyst effect can reach the level of 60-70 grams of carbon dioxide per gram, but the cost is too highIn 2001, Dr. Meng Yuezhong of the Guangzhou Institute of chemistry, Chinese Academy of Sciences, through the loading technology, enabled each gram of catalyst to catalyze 120-140 grams of carbon dioxide, twice the world's highest level, and successfully reduced the cost per ton of finished products to 12000 yuan
application status of carbon dioxide plastics
a large American company used the patent of Japanese scientists in 1969 and began to produce carbon dioxide plastics in 1994, with an annual output of about 20000 tons. Japan has formed a production capacity with an annual output of 3000-4000 tons of carbon dioxide polymers, and South Korea is preparing to build a production line with an annual output of 3000 tons. Due to the high cost and the need to improve the performance of plastics, the manufacture of plastics with carbon dioxide in the United States, Japan and other countries is still in the semi experimental stage in recent years. (Zeng Pingzhi)
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