Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for separating caprolactam from caprolactam sulfate

A technology of caprolactam and sulfate, applied to the preparation of lactam, chemical instruments and methods, preparation/separation of ammonia, etc., to achieve the effects of low equipment requirements, low production cost and good economic benefits

Pending Publication Date: 2022-06-10
HUBEI SANNING CHEM
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This process has been used in the production of caprolactam. Its advantages lie in its mature process, acid-base neutralization to generate salt, and the separation of caprolactam. Its main disadvantage is that it consumes a large amount of ammonia and oleum with high economic value, and the economic value of by-products Lower ammonium sulfate, which increases production costs
Because ammonium sulfate is an inefficient and acidic nitrogen-containing fertilizer, it is unfavorable to the soil and has not been popular in agriculture. The by-product ammonium sulfate is too high, and there is still a problem of difficult sales.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for separating caprolactam from caprolactam sulfate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] In addition, the chloride ion in the solid obtained from the raffinate phase is low, the conversion is complete, and the obtained crystal can be recycled and reused by pyrolysis. For example, the resulting NH 4 HSO 4 Heated to 200°C, decomposed into NH 3 and H 2 SO 4 . or NH 4 HSO 4 Heated to 400°C, decomposed into NH 3 、H 2 O and SO 3 ; can be recycled.

[0026] like figure 1 As shown, the present invention also relates to a device for separating caprolactam from caprolactam sulfate and co-producing compound fertilizer, including a reactor and an extraction tower, and the reactor is provided with a first feed port and a second feed port, wherein the first feed port connects caprolactam The sulfuric acid ester pipeline, the second feeding port is connected to the batching pipeline; the device also includes an ammonium salt batching tank, the batching tank is provided with a batching inlet and a solvent inlet, the batching is ammonium chloride or ammonium carb...

Embodiment 2

[0030] Preferably, the feed inlet of the extraction tower is located at the upper part, and the extractant inlet is provided at the lower part.

[0031] Preferably, the raffinate phase outlet is located at the bottom, and is connected to the compound fertilizer production system through pipelines and pumps.

[0032] Ammonium salts with cheap raw materials are used instead of gas ammonia or liquid ammonia in the traditional process to neutralize the sulfuric acid in caprolactam sulfate, which avoids major safety risks and environmental impacts such as ammonia leakage, poisoning, and explosion, and can greatly reduce production costs.

Embodiment 3

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a method for separating caprolactam from caprolactam sulfate, which mainly comprises the following steps: S1, mixing caprolactam sulfate with ammonium salt, and reacting at 50-150 DEG C to obtain caprolactam and a salt solution; s2, adding an organic solvent into the solution obtained in S1 for extraction to obtain an extraction phase and a raffinate phase; wherein the extraction phase is sent to a caprolactam refining process for refining to obtain caprolactam, and the raffinate phase is an aqueous solution containing ammonium sulfate salt and crystals and is used for preparing a compound fertilizer or directly concentrating and then thermally decomposing to prepare sulfuric acid and ammonia gas. According to the method, caprolactam sulfate is separated into caprolactam and sulfate, ammonium sulfate is used for preparing the compound fertilizer, gas ammonia with high risk is prevented from being used, the operation risk can be reduced, and the cost is saved.

Description

technical field [0001] The invention belongs to the field of chemical industry and relates to the preparation of caprolactam, in particular to a method for separating caprolactam from caprolactam sulfate. Background technique [0002] Caprolactam is an important organic chemical raw material. Its main purpose is to produce polyamide chips (usually called nylon-6 chips, or nylon-6 chips) through polymerization, which can be further processed into nylon fibers, engineering plastics, and plastic films. Nylon-6 slices have different application areas depending on the quality and index. [0003] Using cyclohexanone oxime to carry out Beckmann rearrangement reaction under the action of oleum to obtain caprolactam sulfate, which is then neutralized with ammonia to generate caprolactam and ammonium sulfate. This process has been used in the production of caprolactam. Its advantages lie in its mature process, acid-base neutralization to generate salt, and the separation of caprolact...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C07D223/10C07D201/02C05C3/00C01C1/02C01B17/74
CPCC07D223/10C07D201/02C05C3/00C01C1/028C01B17/745
Inventor 魏天荣李伟方超车小军薛娟娟
Owner HUBEI SANNING CHEM