A kind of protection prepares the acidic ion exchange resin catalyst for lower fatty acid ester method
Technical field
The present invention relates to a kind of protection and prepare the acidic ion exchange resin catalyst for lower fatty acid ester method.In particular to a kind of method of protecting C1-C4 lipid acid and C2-C5 alkene prepared in reaction acidic ion exchange resin catalyst for lower fatty acid ester in liquid phase.
Background technology
Utilize ion exchange resin to make catalyzer, catalysis lower fatty acid and the synthetic low-grade fatty acid ester of low-carbon alkene reaction generally all have reaction effect preferably.But the chemical stability of most of ion-exchange resin catalysts and thermostability are not high, and swelling or loss of active component easily take place life-time service, and then cause catalyst deactivation.
CN1483717 discloses and has utilized modified resin to make catalyzer, and catalysis acetate and propylene reaction under the gas-liquid-solid three-phase condition overcomes and solved side reaction that prior art exists and reaches waste reaction solution more and be difficult to problems such as processing.But because it is reflected under the gas-liquid-solid three-phase condition and carries out, after the propylene reaction in being dissolved in acetate, the propylene of gas phase dissolving earlier enters in the liquid phase, just can proceed reaction, so reaction efficiency is lower.
US5457228 discloses and has utilized styrene sulfonic acid class ion exchange resin or sulfocarbolic acid resinoid to make catalyzer, and catalysis acetate and propylene generate isopropyl acetate, or acetate and 1-butylene, 2 butene reactions prepare sec-butyl acetate.The characteristics of this technology are that the mode of employing tubular fixed-bed reactor and reaction mass mixed cycle has effectively been controlled temperature of reaction, has avoided catalytic erosion, has slowed down catalyst deactivation, has suppressed the generation of reversed reaction speed and olefinic polymerization side reaction.
But according to being familiar with the knowledge that this professional personnel grasp, may contain little metal ion, alkaline matter and S-contained substance as the organic carboxyl acid and the chain alkene of raw material, these materials can be adsorbed on the ion exchange resin, and cause catalyst deactivation.When used alkene is hydrocarbon mixture, as when being hybrid C 4, diene in the hybrid C 4 and iso-butylene are easy to take place coking, thereby cause catalyst deactivation.
Therefore, utilizing ion exchange resin to make catalyzer, when carrying out the esterification of organic carboxyl acid and chain alkene, need carry out pre-treatment, removing the catalyzer toxin and may cause the factor of catalyst deactivation, thereby prolonging catalyzer work-ing life reaction raw materials.
The applicant discloses a kind of before reaction in application number is the patent of CN2007102001475, utilizes amberlite lipid protective material that reaction raw materials is carried out pre-treatment, prolongs the catalyzer method in work-ing life thereby reach.This method is the protective reaction catalyzer effectively, prolongs its catalytic activity, but because protectant exchange capacity is limited, when the catalyzer toxin was more in the reaction raw materials, protective material also was subject to the murder by poisoning of catalyzer toxin and loses protective value gradually.When used alkene is hydrocarbon mixture, as when being hybrid C 4, contain little metal ion, alkaline matter, S-contained substance and greasy filth in the hybrid C 4.Metal ion, alkaline matter, S-contained substance are catalyzer poisons, and greasy filth then can cause catalyst deactivation attached to catalyst surface.
Summary of the invention
The purpose of this invention is to provide and a kind ofly prepare in the process of low-grade fatty acid ester the method for protection acidic ion exchange resin catalyst at C1-C4 lipid acid and C2-C5 olefine reaction.
Purpose of the present invention is achieved through the following technical solutions: before reactant advances reactor, earlier C2-C5 alkene is washed removing the part catalyzer toxin in the alkene, and reactant C1-C4 lipid acid and C2-C5 alkene or wherein a kind of are removed detrimental impurity through a pretreater that reaction promoter is housed.
C1-C4 lipid acid is the lipid acid of 1~4 carbon atom, and the lipid acid of 1~4 carbon atom can be formic acid, acetate, propionic acid, butanic acid, isopropylformic acid, vinylformic acid, wherein preferred acetate.
C2-C5 alkene can be ethene, propylene, 1-butylene, 2 butylene, iso-butylene, 1-amylene or 2 amylenes, preferred propylene, 1-butylene, 2-butylene.
In the reaction that utilizes C1-C4 lipid acid and C2-C5 olefin production low-grade fatty acid ester, sometimes alkene contains metal ion, alkaline matter and S-contained substance, and these metal ions, alkaline matter and S-contained substance can cause the acidic ion exchange resin catalyst inactivation.When used alkene is hydrocarbon mixture, as when being hybrid C 4, also contain greasy filth in the hybrid C 4, these greasy filth can cause catalyst deactivation attached to catalyst surface.By washing, can wash above-mentioned catalyzer toxin of part and greasy filth off, thereby play the purpose of guard catalyst.
The mass flux ratio that the flow of washing water should be controlled to be water and hydrocarbons is 0~10, is preferably 0~3.Generally speaking, the mass flux ratio of water and hydrocarbons increases, and water washing effect is better, but when the mass flux ratio of water and hydrocarbons greater than 10, then the water yield of Xiao Haoing is too big, operates uneconomical.Washing water also can be statically placed in water wash column or water washing tank or the washing bath, and at this moment, the mass rate of washing water is 0, and hydrocarbons passes through the washing water layer, thereby reaches water washing effect.
Because water can impact reaction and catalyzer, therefore, need take required measure moisture less to guarantee in the hydrocarbon of washing back.The dewatering that the technician adopted of being familiar with the industry all can be used as the optional dewatering means of present method, adds the water bag as water washing tank/groove or hydrocarbon tundish thereafter, or after the washing, with the coalescer that coalescent filter core be housed of hydrocarbons by dehydration etc.
Reactant C1-C4 lipid acid and C2-C5 alkene or wherein a kind of are removed detrimental impurity through a pretreater that reaction promoter is housed.
Reaction promoter in the pretreater is an ion exchange resin, and its exchange capacity need not be controlled especially, but generally should not be less than 3mmol/gH, and the example of alternative ion exchange resin has: S54 type ion exchange resin, D72 type ion exchange resin.
Use the purpose of reaction promoter to mainly contain 3 points: the one, remove the metal ion that contains in the reaction raw materials; The 2nd, alkaline matter in the reaction raw materials and S-contained substance are absorbed; The 3rd, when used alkene is hybrid C 4, diene in the hybrid C 4 and iso-butylene and organic carboxyl acid is at first reacted, thereby avoid in reactor, taking place coking.
The temperature of pretreater is 20~80 ℃, its objective is guaranteeing under the unobstructed condition of logistics the detrimental impurity in the material fully to be absorbed; Diene in the hybrid C 4 and iso-butylene and organic carboxyl acid are reacted.
The present invention has following technique effect: detrimental impurity was removed before material entered reactor; can prevent poisoning of catalyst; catalyzer uses does not have deactivation phenomenom more than 6 months; and the reaction promoter that plays the catalyst protection effect does not have metal ion to wear the filter phenomenon, and the front and back pressure reduction of reaction promoter bed changes little.
Embodiment
The present invention is further illustrated by the following examples, but content not thereby limiting the invention.
In an embodiment: acetate purity 〉=99.5%; Hybrid C 4 is formed: 1-butylene 4.72%, 2-butylene 49.22%, butane 46.01%, iso-butylene 0.05%.
Embodiment 1: the employing specific surface area is 30m
2/ g, pore volume are 0.25ml/g, and granularity is that the strong-acid ion exchange resin of 1.0mm is made catalyzer.With total amount is that the catalyzer of 3.5t is packed into and split in the tubular reactor.Vinylbenzene-divinylbenzene polymerization bead is then loaded at the two ends of catalyst layer.
Is that 5 speed feeds water wash column with de-salted water and hybrid C 4 with mass flux ratio.
Hybrid C 4 after washing and acetate feed the pretreater that D72 type ion exchange resin is housed, and the mol ratio of butylene in acetate and the hybrid C 4 (sour alkene ratio) is 1.3, and feeding manner is a liquid phase feeding.The temperature out of pretreater is 70 ℃.
Will be through pretreated acetate and hybrid C 4 from the continuous input reactor of reactor bottom, the acetic acid feed air speed is 1.0hr
-1, reaction pressure is 1.6MPa, temperature of reaction is 110 ℃.
Every 8hr sampling analysis reaction product is formed, and analyzes and adopts vapor-phase chromatography.Recording the sec-butyl acetate selectivity reaches more than 98%.Initial reaction stage, Fe, Cr, Ni ionic concn are all less than 0.01 μ g/g in the pretreater afterreaction medium, and pressure reduction is less than 0.1MPa before and after the reaction promoter bed.Move 6 months, catalyst activity is stable, and considerable change does not appear in reaction conversion ratio and selectivity, and Fe, Cr, Ni ionic concn are all less than 0.01 μ g/g in the pretreater afterreaction medium, and pressure reduction is less than 0.1MPa before and after the reaction promoter bed.
The comparative example 1: the employing specific surface area is 30m
2/ g, pore volume are 0.25ml/g, and granularity is that the strong-acid ion exchange resin of 1.0mm is made catalyzer.With total amount is that the catalyzer of 3.5t is packed into and split in the tubular reactor.Vinylbenzene-divinylbenzene polymerization bead is then loaded at the two ends of catalyst layer.
Hybrid C 4 and acetate are fed the pretreater that D72 type ion exchange resin is housed, and the mol ratio of butylene in acetate and the hybrid C 4 (sour alkene ratio) is 1.3, and feeding manner is a liquid phase feeding.The temperature out of pretreater is 70 ℃.
Will be through pretreated acetate and hybrid C 4 from the continuous input reactor of reactor bottom, the acetic acid feed air speed is 1.0hr
-1, reaction pressure is 1.6MPa, temperature of reaction is 110 ℃.
Every 8hr sampling analysis reaction product is formed, and analyzes and adopts vapor-phase chromatography.Recording the sec-butyl acetate selectivity reaches more than 98%.Initial reaction stage, Fe, Cr, Ni ionic concn are all less than 0.01 μ g/g in the pretreater afterreaction medium, and pressure reduction is less than 0.1MPa before and after the reaction promoter bed.Move after 1 month, pressure reduction begins slightly to increase before and after the reaction promoter bed.Move after 4 months, the Fe ionic concn reaches 9.6 μ g/g in the pretreater afterreaction medium, and pressure reduction reaches 0.4MPa before and after the reaction promoter bed.
Embodiment 2: the employing specific surface area is 30m
2/ g, pore volume are 0.25ml/g, and granularity is that the strong-acid ion exchange resin of 1.0mm is made catalyzer.With total amount is that the catalyzer of 3.5t is packed into and split in the tubular reactor.Vinylbenzene-divinylbenzene polymerization bead is then loaded at the two ends of catalyst layer.
Is that 5 speed feeds water wash column with de-salted water and hybrid C 4 with mass flux ratio.Acetate is fed the pretreater that D72 type ion exchange resin is housed, and the temperature out of pretreater is 70 ℃.
Will be after pretreated acetate and hybrid C 4 mixing, from the continuous input reactor of reactor bottom, the mol ratio of butylene in acetate and the hybrid C 4 (sour alkene ratio) is 1.3, feeding manner is a liquid phase feeding.The acetic acid feed air speed is 1.0hr
-1, reaction pressure is 1.6MPa, temperature of reaction is 110 ℃.
Every 8hr sampling analysis reaction product is formed, and analyzes and adopts vapor-phase chromatography.Recording the sec-butyl acetate selectivity reaches more than 98%.Initial reaction stage, Fe, Cr, Ni ionic concn are all less than 0.01 μ g/g in the pretreater afterreaction medium, and pressure reduction is less than 0.1MPa before and after the reaction promoter bed.Move 3 months, catalyst activity is stable, and considerable change does not appear in reaction conversion ratio and selectivity, and Fe, Cr, Ni ionic concn are all less than 0.01 μ g/g in the pretreater afterreaction medium, and pressure reduction is less than 0.1MPa before and after the reaction promoter bed.
Embodiment 3: the employing specific surface area is 30m
2/ g, pore volume are 0.25ml/g, and granularity is that the strong-acid ion exchange resin of 1.0mm is made catalyzer.With total amount is that the catalyzer of 3.5t is packed into and split in the tubular reactor.Vinylbenzene-divinylbenzene polymerization bead is then loaded at the two ends of catalyst layer.
Hybrid C 4 is fed the water washing tank that de-salted water is housed.Acetate is fed the pretreater that D72 type ion exchange resin is housed, and the temperature out of pretreater is 70 ℃.
After acetate and hybrid C 4 mixing, from the continuous input reactor of reactor bottom, the mol ratio of butylene in acetate and the hybrid C 4 (sour alkene ratio) is 1.3, and feeding manner is a liquid phase feeding.The acetic acid feed air speed is 1.0hr
-1, reaction pressure is 1.6MPa, temperature of reaction is 110 ℃.
Every 8hr sampling analysis reaction product is formed, and analyzes and adopts vapor-phase chromatography.Recording the sec-butyl acetate selectivity reaches more than 98%.Move 80 days, catalyst activity is stable, and considerable change does not appear in reaction conversion ratio and selectivity.Fe, Cr, Ni ionic concn are all less than 0.01 μ g/g in the pretreater afterreaction medium, and pressure reduction is less than 0.1MPa before and after the reaction promoter bed.