CN102234233A

CN102234233A - Method for extracting organic matters from waste acid during nitrochlorobenzene production

Info

Publication number: CN102234233A
Application number: CN2010101560765A
Authority: CN
Inventors: 李德昌; 孙健; 桂跃; 赵强; 李兵
Original assignee: Anhui Bayi Chemical Industry Co Ltd
Current assignee: Anhui Bayi Chemical Industry Co Ltd
Priority date: 2010-04-20
Filing date: 2010-04-20
Publication date: 2011-11-09

Abstract

The invention relates to a method for extracting organic matters from waste acid during nitrochlorobenzene production. The method comprises the following steps: adding waste acid and chlorobenzene into an extraction column; stirring the mixed waste acid and chlorobenzene; and discharging a layered chlorobenzene phase containing organic matters and a diluted acid phase when the organic matter content in the waste acid is less than 100 PPm, and continuing adding waste acid and chlorobenzene to the extraction column in the discharging process so as to maintain a running state of continuous balanced discharging and adding. The method provided by the invention has the beneficial effects that the process flow is simplified, and equipment and production sites are saved; the extraction effect is good, and cost is saved; the organic matters are cleaned during subsequent acid recovery treatment through acid distilling without stopping working so as to lower the wastewater treatment cost, thereby lowering the production cost of nitrochlorobenzene; and the method has the advantages of fully automatic operation, stable running, high treatment capacity and high operating flexibility, and is adaptable to large-scale industrial continuous production.

Description

The method of extraction Organic Materials of Spent acid in the nitro benzene chloride production

Technical field

The present invention relates to the organic method of extraction from spent acid, the method for extraction Organic Materials of Spent acid in specifically a kind of nitro benzene chloride production.

Background technology

The production of nitro-chlorobenzene is to adopt Benzene Chloride and a certain amount of nitric acid and the reaction of sulfuric acid nitration mixture to make, and will adopt Benzene Chloride to carry out extraction treatment usually for the spent acid that produces in the nitro benzene chloride production, so that the organic substance extraction in the spent acid is recycled.The method of existing extraction Organic Materials of Spent acid is: earlier spent acid and Benzene Chloride are advanced extraction pot (the cooking-pot type reactor that band stirs) and mixed, since Benzene Chloride to the solubleness that remains in the organism (mainly being nitro-chlorobenzene) in the spent acid greater than the solubleness in diluted acid, in the spent acid the most of organism of dissolved enter Benzene Chloride mutually in, then mixed solution is entered large-scale vertical layering jar, after leaving standstill by the regular hour, the upper strata is for containing organic Benzene Chloride phase, lower floor is extracting phase-diluted acid (claiming spent acid usually) phase, then with the Benzene Chloride phase, extracting phase flows to storage tank separately.Above-mentioned existing extracting process adopts traditional extraction pot+layering jar separating and extracting process, the shortcoming that exists is: 1, layered approach is simple, layering is not thorough, Organic Materials of Spent acid can only drop to 500～1000ppm, residual organic content is still higher in the spent acid, because this organism zero pour higher (60～75 ℃), in follow-up steaming acid recovery acid treatment, can cause organism enrichment in system device, this not only influences the acid treatment ability of steaming, but also the cleaning organic matter that will often stop, it is discontented to cause the device load to drive, influence the timely of spent acid, effectively handle reuse, also can cause in the processed waste water organic content big simultaneously, make wastewater treatment difficulty and intensity increase, it is big to handle the waste water cost; 2, extraction pot extraction stirring is big with power of motor, and stirring and mixing effect is poor, and the extraction residence time is short, and effect of extracting is poor; 3, equipment used is many, and the hold facility production site is big, and extraction is for carrying out step by step, and efficient is lower, the cost height of extraction.

Summary of the invention

The object of the present invention is to provide in a kind of nitro benzene chloride production the method for extraction Organic Materials of Spent acid, the Organic Materials of Spent acid content after this method extraction is low, and this method steps compactness, equipment used is few, efficient is high.

For achieving the above object, the present invention adopts following scheme:

The method of extraction Organic Materials of Spent acid in the nitro benzene chloride production may further comprise the steps: add spent acid and Benzene Chloride in extraction tower; Blended spent acid and Benzene Chloride are stirred; After the organic content in the spent acid is less than 100PPm, contain organic Benzene Chloride and reach diluted acid mutually and discharge mutually stratified, in discharge process, continue in extraction tower, to add spent acid and Benzene Chloride, while keep the running status of discharging, adding of continuous equilibrium.

Adding the spent acid in the extraction tower and the volumetric ratio of Benzene Chloride first is 4: 3, while in service what discharge, add, the stable spent acid that adds and the throughput ratio of Benzene Chloride are 4: 3.

The beneficial effect that adopts above scheme to have is: 1, will extract and be separated in the equipment and carry out simultaneously, and simplify technical process, and save equipment and production site; 2, extraction is effective, compares with existing technology, can more reclaim organism from spent acid, and then reach the effect of economizing on the use of funds more; 3, reduced the enrichment of organism in system device in the follow-up steaming acid recovery acid treatment, avoid the cleaning organic matter that stops, guarantee to steam the acid treatment ability, reduced organic content in the follow-up waste water simultaneously, wastewater treatment difficulty and intensity have been reduced, reduce the wastewater treatment expense, accomplished wastewater treatment resource utilization, innoxious, minimizing, and then reduced the manufacturing cost that whole nitro-chlorobenzene is produced; But 4 unattended operations are stable, and it is big to handle load, and turndown ratio is big, is adapted to the heavy industrialization continuous production.

Description of drawings

Accompanying drawing is the structural representation of the extraction tower that one embodiment of the invention adopted.

Embodiment

Further specify the present invention below in conjunction with embodiment and accompanying drawing.

Referring to accompanying drawing, have opening for feed 5, opening for feed 4, discharge port 2, discharge port 3 on the body of the tower 1 of extraction tower of the present invention, have rotating disk 6 in the body of the tower 1 by motor 7 controls, the step that adopts extraction tower to extract in the spent acid is as follows:

1, opens opening for feed 5, earlier in extraction tower, advance spent acid, when charging reaches extraction tower useful volume 4/7 left and right sides, close opening for feed 5, open opening for feed 4, in extraction tower, advance Benzene Chloride, when institute advances Benzene Chloride and is extraction tower useful volume 3/7 left and right sides, close opening for feed 4;

2, start motor 7 transmission rotating disks 6,10-25 rev/min of the low-grade rotational speed of control rotating disk stirs blended spent acid and Benzene Chloride;

3, after about 1 hour, nitro-chlorobenzene content in the analytical extraction tower bottom spent acid, behind content＜100ppm, open discharge port 2 and discharge port 3, will be in containing of upper strata organic Benzene Chloride by discharge port 2 discharging, the diluted acid that will be in lower floor is discharged by discharge port 3, in discharge process, open opening for feed 5, opening for feed 4, add spent acid and Benzene Chloride simultaneously in extraction tower, (add-on of spent acid begins to be 2m to the ascending raising gradually of the add-on of spent acid ³/ h), final stability of flow is to 8m ³/ h, same, (add-on of Benzene Chloride begins to be 2m to the also ascending raising gradually of the add-on of Benzene Chloride ³/ h), final stability of flow is to 6m ³/ h, the rotating speed of control rotating disk 6 is 35～45 rev/mins, after this, while keep the running status of discharging, adding of this continous-stable, and keep discharging and add balance.Under the running status of this continous-stable, the content of the Organic Materials of Spent acid that sampling analysis is discharged is 60～70ppm.

Claims

1. the method for extraction Organic Materials of Spent acid in the nitro benzene chloride production is characterized in that may further comprise the steps: add spent acid and Benzene Chloride in extraction tower; Blended spent acid and Benzene Chloride are stirred; After the organic content in the spent acid is less than 100PPm, contain organic Benzene Chloride and reach diluted acid mutually and discharge mutually stratified, in discharge process, continue in extraction tower, to add spent acid and Benzene Chloride, while keep the running status of discharging, adding of continuous equilibrium.

2. the method for extraction Organic Materials of Spent acid in the nitro benzene chloride production according to claim 1, it is characterized in that: adding the spent acid in the extraction tower and the volumetric ratio of Benzene Chloride first is 4: 3, in service while what discharge, add, the stable spent acid that adds and the throughput ratio of Benzene Chloride are 4: 3.