A kind of method reclaiming double trimethylolpropane the residual liquid from trimethylolpropane
Technical field
The present invention relates to a kind of method reclaiming double trimethylolpropane residual liquid from trimethylolpropane, belong to and become more meticulous
Separation in work technical field purifies part again.
Background technology
A kind of by-product being commonly called as double trimethylolpropane can be produced, due to double three hydroxyls in trimethylolpropane production process
The yield of methylpropane seldom so price is higher, 2-3 times of usually trimethylolpropane.Therefore improve double as far as possible
The yield of trimethylolpropane is the research direction that enterprise increases benefit.The existing general warp of method reclaiming double trimethylolpropane
Cross the step such as decolour, filter, crystallize, refilter, evaporate and cut into slices, wherein one time mother solution is through extraction tower by the trihydroxy methyl of the inside
Propane and double trimethylolpropane extract, and are then passed through solvent recycling tower recycling design, bottom of towe is still containing 15% about
Trimethylolpropane and 50% about double trimethylolpropane residual liquid.
The domestic at present process for above-mentioned residual liquid typically has two ways, and one is residual liquid to be transported to solid waste burned
Steam, because gas production is very low, directly burn very uneconomical and contaminated air.Two are used to do the binding agent of resin, but set
Its price of fat is relatively low, also uneconomical.So how in residual liquid 50% double trimethylolpropane to be carried out reclaiming the increase of Ze Shi enterprise
The research direction of benefit, Japan once had and using solvent, residual liquid is carried out low-temperature extraction and reclaim certain double trihydroxy methyls third
The research of alkane, but organic efficiency is not high.
Therefore research and develop a kind of method gesture how preferably reclaiming double trimethylolpropane from trimethylolpropane residual liquid
Must go.
Content of the invention
The technical problem to be solved in the present invention provides a kind of utilization double trimethylolpropane in ketone, alcohols and water
Crystallization degree is different, and under the same terms, double trimethylolpropane is easier the principle in ketone, alcohols intercrystalline, and then from three hydroxyls
The method reclaiming more double trimethylolpropanes in methylpropane residual liquid.
For solving above-mentioned technical problem, the technical scheme is that:A kind of recovery pair from trimethylolpropane residual liquid
The method of trimethylolpropane, its innovative point is that methods described is:Step S1:First by acetone and ethanol in mass ratio 2:1
The mixed solvent prepared adds in crystallization kettle;And add trimethylolpropane residual liquid identical with solvent quality in crystallization kettle;Step
Rapid S2:After having added trimethylolpropane residual liquid, keep crystallization kettle in -5~-10 DEG C of thermostatical crystallization 3-5h;Step S3:To crystallize
Material in kettle is delivered in filter and is filtered, and first connects filter and crystallization kettle by circulating line when filtering and starting
Then material is passed through Matter Transfer circuit cycle for a period of time, body to be crystallized starts shape by one Matter Transfer loop of logical composition
Cheng Hou, carries out being filtrated to get filter cake and filtrate, and filtrate is delivered to recovery double trimethylolpropane mother liquor tank;Step S4:To walk
The filter cake being filtrated to get in rapid S3 is warming up to 80 DEG C~120 DEG C in filter and is melted, and filter is carried out taking out very simultaneously
Empty extremely -0.095 MPa~-0.098MPa, persistent period 0.5h~1h, the solvent removal in filter cake is clean, obtain double three hydroxyls
Methylpropane;Step S5:Recovery double trimethylolpropane mother liquor tank is delivered to mother liquid evaporation kettle after reaching certain liquid level and is steamed
Send out, solvent is evaporated to be recovered to solvent tank and recycle after the condensation of condensed device group.
Preferably, in described step S3, after the completion of filtration, purge filter 30 ~ 40min using nitrogen.
It is an advantage of the current invention that:
1. the double trimethylolpropane of 40 more than % in residual liquid can be reclaimed by this method, make full use of resource, reduce
Production cost, improves economic benefit and product competitiveness.
2. realize the requirement of clear production, although originally residual liquid directly burns to steam and brings a small amount of economic valency
Value, but waste gas in burning process, can be produced, after this method purification, the total amount of residual liquid decreases half, just permissible by taking out
Directly digest, avoid burning to bring waste gas as far as possible, accomplished the purpose of clean manufacturing.
Specific embodiment
Embodiment one
Step S1:First by acetone and ethanol in mass ratio 2:The mixed solvent of 1 preparation adds in crystallization kettle, and addition is
5t;And add 5t trimethylolpropane residual liquid in crystallization kettle, after testing, in residual liquid, double trimethylolpropane content is 50%;
Step S2:After having added trimethylolpropane residual liquid, keep crystallization kettle thermostatical crystallization 5h at -7 DEG C;
Step S3:Material in crystallization kettle is delivered in filter and is filtered, when filtering beginning first by filter
With crystallization kettle, one Matter Transfer loop of composition is connected by circulating line, then material is passed through Matter Transfer circuit cycle
After 1h, 1h, carry out being filtrated to get filter cake and filtrate, filtrate is delivered to recovery double trimethylolpropane mother liquor tank, filtration completes
Purge filter 40min using nitrogen afterwards;
Step S4:The filter cake being filtrated to get in step S3 is warming up to 120 DEG C in filter melted, simultaneously to mistake
Filter carries out being evacuated to -0.095 MPa~-0.098MPa, persistent period 0.5h~1h, and the solvent removal in filter cake is done
Only, obtain 90% about double trimethylolpropane 2.7T;
Step S5:Recovery double trimethylolpropane mother liquor tank is delivered to mother liquid evaporation kettle after reaching certain liquid level and is evaporated,
Solvent is evaporated to be recovered to solvent tank and recycles after the condensation of condensed device group.
Content through checking recycling design is more than 99%, in the remaining residual liquid of mother liquid evaporation kettle, not double three hydroxyl first of crystallization
In base propane and trimethylolpropane residual liquid, double trimethylolpropane content is less than 5%.
Embodiment two
Step S1:First by acetone and ethanol in mass ratio 2:The mixed solvent of 1 preparation adds in crystallization kettle, and addition is
3t;And add 3t trimethylolpropane residual liquid in crystallization kettle, after testing, in residual liquid, double trimethylolpropane content is 50%;
Step S2:After having added trimethylolpropane residual liquid, keep crystallization kettle thermostatical crystallization 3h at -10 DEG C;
Step S3:Material in crystallization kettle is delivered in filter and is filtered, when filtering beginning first by filter
With crystallization kettle, one Matter Transfer loop of composition is connected by circulating line, then material is passed through Matter Transfer circuit cycle
After 1h, 1h, carry out being filtrated to get filter cake and filtrate, filtrate is delivered to recovery double trimethylolpropane mother liquor tank, filtration completes
Purge filter 30min using nitrogen afterwards;
Step S4:The filter cake being filtrated to get in step S3 is warming up to 80 DEG C in filter melted, simultaneously to mistake
Filter carries out being evacuated to -0.095 MPa~-0.098MPa, persistent period 0.5h~1h, and the solvent removal in filter cake is done
Only, obtain 92% about double trimethylolpropane 1.7T;
Step S5:Recovery double trimethylolpropane mother liquor tank is delivered to mother liquid evaporation kettle after reaching certain liquid level and is evaporated,
Solvent is evaporated to be recovered to solvent tank and recycles after the condensation of condensed device group.
Content through checking recycling design is more than 98.8%, in the remaining residual liquid of mother liquid evaporation kettle, not double three hydroxyls of crystallization
In methylpropane and trimethylolpropane residual liquid, double trimethylolpropane content is less than 5.2%.
Embodiment three
Step S1:First by acetone and ethanol in mass ratio 2:The mixed solvent of 1 preparation adds in crystallization kettle, and addition is
4t;And add 4t trimethylolpropane residual liquid in crystallization kettle;After testing, in residual liquid, double trimethylolpropane content is 50%;
Step S2:After having added trimethylolpropane residual liquid, keep crystallization kettle thermostatical crystallization 4h at -5 DEG C;
Step S3:Material in crystallization kettle is delivered in filter and is filtered, when filtering beginning first by filter
With crystallization kettle, one Matter Transfer loop of composition is connected by circulating line, then material is passed through Matter Transfer circuit cycle
After 1h, 1h, carry out being filtrated to get filter cake and filtrate, filtrate is delivered to recovery double trimethylolpropane mother liquor tank, filtration completes
Purge filter 35min using nitrogen afterwards;
Step S4:The filter cake being filtrated to get in step S3 is warming up to 100 DEG C in filter melted, simultaneously to mistake
Filter carries out being evacuated to -0.095 MPa~-0.098MPa, persistent period 0.5h~1h, and the solvent removal in filter cake is done
Only, obtain not solvent-laden double trimethylolpropane;Obtain the double trimethylolpropane 2.3T of 91% content;
Step S5:Recovery double trimethylolpropane mother liquor tank is delivered to mother liquid evaporation kettle after reaching certain liquid level and is evaporated,
Solvent is evaporated to be recovered to solvent tank and recycles after the condensation of condensed device group.
Content through checking recycling design is more than 98.9%, in the remaining residual liquid of mother liquid evaporation kettle, not double three hydroxyls of crystallization
In methylpropane and trimethylolpropane residual liquid, double trimethylolpropane content is less than 5.3%.