The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great difference...The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences,static melt crystallization was applied to separate and purify durene from its isomers.Crystallization experiments were carried out under various operating conditions.The effects of cooling rate,crystallization temperature,sweating temperature and sweating time on the yield and purity of crystal were investigated.Orthogonal experimental design method was adopted to analyze the factors that may affect the yield of durene.Under the optimal crystallization conditions,the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystallization process.By fitting purification data based on sweating time in isothermal operations,the purification rate coefficient was obtained.展开更多
2,6-Diisopropylnaphthalene (2,6-DIPN), as the precursor of important monomer 2,6-naphthalene dicarboxylic acid, could be produced by the shape-selective isopropylation of naphthalene with propene resulting in an iso...2,6-Diisopropylnaphthalene (2,6-DIPN), as the precursor of important monomer 2,6-naphthalene dicarboxylic acid, could be produced by the shape-selective isopropylation of naphthalene with propene resulting in an isomeric mixture having different alkylation levels. Since the boiling points of DIPNs were very close and the differences of melting points in-between isomers were quite distinctive, the static melt crystallization was applied to separate and purify 2,6-DIPN from its isomers. 2,6-DIPN with purity ≥99% was produced through a process of three stages: crystallization→sweating→melting. The phase diagram of 2,6-DIPN-2,7-DIPN binary system was plotted to opti- mize the temperature control of crystallization. By repeated crystallization of melts with different concentration levels, the yield of pure 2,6-DIPN could be enhanced to 87%. No solvent was necessary. Keywords 2,6-diisopropylnaphthalene, static melt crystallization, crystallization rate, sweating rate, eutectic temperature展开更多
2,6-Diisopropylnaphthalene(2,6-DIPN),as the precursor of important monomer 2,6-naphthalene dicarboxylic acid,was prepared by hydroisopropylation of refined naphthalene with propene over shape-selective catalyst.Naph...2,6-Diisopropylnaphthalene(2,6-DIPN),as the precursor of important monomer 2,6-naphthalene dicarboxylic acid,was prepared by hydroisopropylation of refined naphthalene with propene over shape-selective catalyst.Naphthalene conversion of 92% and 2,6-DIPN selectivity of 64% were obtained.Static melt crystallization was applied to separate and purify 2,6-DIPN from its isomers,resulted in a product purity of≥99%.The other isomers were converted into monoisopropylnaphthalene,which also reacted with propene to form 2,6-DIPN.A recycled process including hydroisopropylation,separation and transalkylation was established,the yield of 2,6-DIPN based on naphthalene could be doubled by one cycle operation.展开更多
基金Supported by the National Natural Science Foundation of China(21176172)Top Talents Program of Yunnan Province,China(2011HA010)
文摘The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences,static melt crystallization was applied to separate and purify durene from its isomers.Crystallization experiments were carried out under various operating conditions.The effects of cooling rate,crystallization temperature,sweating temperature and sweating time on the yield and purity of crystal were investigated.Orthogonal experimental design method was adopted to analyze the factors that may affect the yield of durene.Under the optimal crystallization conditions,the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystallization process.By fitting purification data based on sweating time in isothermal operations,the purification rate coefficient was obtained.
文摘2,6-Diisopropylnaphthalene (2,6-DIPN), as the precursor of important monomer 2,6-naphthalene dicarboxylic acid, could be produced by the shape-selective isopropylation of naphthalene with propene resulting in an isomeric mixture having different alkylation levels. Since the boiling points of DIPNs were very close and the differences of melting points in-between isomers were quite distinctive, the static melt crystallization was applied to separate and purify 2,6-DIPN from its isomers. 2,6-DIPN with purity ≥99% was produced through a process of three stages: crystallization→sweating→melting. The phase diagram of 2,6-DIPN-2,7-DIPN binary system was plotted to opti- mize the temperature control of crystallization. By repeated crystallization of melts with different concentration levels, the yield of pure 2,6-DIPN could be enhanced to 87%. No solvent was necessary. Keywords 2,6-diisopropylnaphthalene, static melt crystallization, crystallization rate, sweating rate, eutectic temperature
文摘2,6-Diisopropylnaphthalene(2,6-DIPN),as the precursor of important monomer 2,6-naphthalene dicarboxylic acid,was prepared by hydroisopropylation of refined naphthalene with propene over shape-selective catalyst.Naphthalene conversion of 92% and 2,6-DIPN selectivity of 64% were obtained.Static melt crystallization was applied to separate and purify 2,6-DIPN from its isomers,resulted in a product purity of≥99%.The other isomers were converted into monoisopropylnaphthalene,which also reacted with propene to form 2,6-DIPN.A recycled process including hydroisopropylation,separation and transalkylation was established,the yield of 2,6-DIPN based on naphthalene could be doubled by one cycle operation.