Reactions Of Calcium Carbide With Methanol And Methanol Derivative

With the rapid economic development in recent years, demand for energy and chemical products also continues to rise at a high growth rate. Fossil fuels maintain a large proportion in primary energy structure and the consumption is very huge.Development of coal chemical engineering relying on the rich coal resources can make up the lack of domestic oil and gas resources and meet the demand for chemical products and play an important realistic and long-term significance in energy security and sustainable development.Calcium carbide based on coal and coal to methanol and methanol derivative belong to an important branch of coal chemical engineering.In recent years, the development of oxygen-thermal synthesis of calcium carbide technology has greatly promoted the development of calcium carbide and its derivative.Especially after the Eleventh Five-Year Plan, coal to methanol technology has developed rapidly in China.As a result, excess methanol needs to develop new derivative.Calcium carbide is reacted with water to give acetylene, generated acetylene participates other reactions in early years.The molecular structure of methanol is similar to water, which provides the possibility of the study of the reaction of calcium carbide with methanol.In the late 1960s, American researchers found that calcium carbide can react with alcohol to generate vinyl ether compound, but they explored no more deeper study and this method was not attractive.Our group did further research of the reaction of calcium carbide with methanol,ethanol and n-propanol based on the above finding. The study found that the main product of reaction of calcium carbide with methanol is vinyl methyl ether at low temperature(120-250℃).And the main product of reaction of calcium carbide with ethanol is butanol and the main product of reaction of calcium carbide with n-propanol is hexanol,but the ethanol cannot generate from methanol by increasing carbon chain.In order to study the possibility of ethanol generating from the reaction of calcium carbide with m ethanol and improve the yield of vinyl methyl ether and make the understanding of their predecessors perfect, this paper explores the detailed reaction conditions. Because acetylene generating from the reaction of calcium carbide with water can react with carbonyl compound, and acetone as an important derivative of methanol containing a carbonyl group, in order to enrich the derivative of calcium carbide, our group also studied the reaction of calcium carbide with acetone. From this work, we can draw a conclusion as below:(1) Calcium carbide can react with methanol to generate ethanol at high temperature(280-400℃), but ethanol is not derived from the reaction of two molecules of methanol, from the reaction of methanol and synthesis gas, synthesis gas from the decomposition of methanol at high temperature.(2)Calcium carbide can react with methanol to generate vinyl methyl ether at low temperature(80-160℃).The catalyst, reaction temperature,reaction time, and solvent system are the main factors affecting the yield of the vinyl methyl ether. In the study conditions, the yield of vinyl methyl ether in DMSO and NMP increases with the temperature increasing at first, then it begins to decrease when the temperature is over 100℃.The selectivity of it decreases with the temperature increasing.The yield and selectivity of vinyl methyl ether in DMSO is higher than that in NMP. The yield of the vinyl methyl ether increase and the selectivity of it decrease with the time increasing in DMSO.(3)Calcium carbide can react with acetone to generate 2-methyl-3-butyn-2-ol and 4-methyl-3-penten-2-one under mild reaction conditions(50-80℃), in the study conditions, the yield of 2-methyl-3-butyn-2-ol and 4-methyl-3-penten-2-one increases with the temperature increasing at first, then they begin to decrease when the temperature is over 60℃, The selectivity of 2-methyl-3-butyn-2-ol increases and the selectivity of 4-methyl-3-penten-2-one decreases with the temperature increasing.The yield and selectivity of 2-methyl-3-butyn-2-ol increase with the time increasing.