CN102617354A - Refining process of o-nitrophenol - Google Patents

Abstract

The invention belongs to the technical field of chemical engineering and particularly relates to a refining process of o-nitrophenol. According to the refining process of the o-nitrophenol, 100kg of o-nitroanisole is excessively recovered from per 10 tons of waste water, and the production cost of the o-nitroanisole is reduced. Active carbon is added for absorption, the purity of the o-nitrophenol is improved, and the original content lower than 95 percent is improved to the content higher than 99 percent. The activated carbon regeneration is carried out, the o-nitroanisole is further extracted, activated carbon can be cyclically utilized, and meanwhile, the recovery rate of the o-nitroanisole is improved. In the original process, the purification can be carried out only through the rectification. According to the refining process provided by the invention, the purity of the o-nitrophenol can be improved through distillation, and energy sources and equipment are saved. The waste water chemical oxygen demand (COD) is reduced by a half through being compared with the results of the original process, impurities are absorbed by the active carbon, the content of the impurities is greatly reduced, and the waste water treatment by resin absorption is favorably realized.

Description

The process for refining of o-NP

Technical field

The invention belongs to chemical technology field, be specifically related to a kind of process for refining of o-NP.

Background technology

The production technique of o-NP, comparatively ripe at present, still, all there are some defectives in various production technique, and for example, when producing o-NP through o-Nitrophenyl methyl ether, defective workmanship mainly is present in:

1, o-NP content is difficult to surpass 95%.

2, the o-Nitrophenyl methyl ether in the removal process is a mixture, is difficult to handle and recycle.

3, the waste water COD that produces is higher, reaches 4000mg/l, and environmental protection water treatment difficulty is bigger.

4, this arts demand acid out-distillation operation, with raising purity, but energy consumption is higher.

Summary of the invention

To the problem that exists in the prior art, the present invention aims to provide the process for refining of the o-NP that a kind of cost is lower, product purity is higher.

The technical scheme that the present invention adopts is following:

The process for refining of o-NP is characterized in that, comprises the steps:

1., methyl ether oxidation mother liquor water is squeezed into storage tank, utilize the condensing surface cooling that circulates, temperature drops to below 30 ℃;

2., left standstill 1 hour, squeeze into Decolouring pot to water at the middle and upper levels; Lower floor's material can be returned oxidation system, reclaims o-Nitrophenyl methyl ether;

3., in Decolouring pot, add 1% powdered carbon, be warming up to 60 ℃, decoloured 1 hour;

4., the decolouring qualified after, destainer carries out press filtration through pressure filter, the filter residue gac goes out o-Nitrophenyl methyl ether with methanol extraction, again recovered carbon;

5., filtrating is squeezed into the acidifying pot, drip the vitriol oil, control pH value reaches 3, stopping acidification; Cool to 25 ℃ after the acidifying, o-NP is fully separated out;

6., under whipped state, squeeze into acidizing fluid and take out hopper, take out changing over to of hopper material material pot, lower layer of water gets into the pot that draws water, the water of the pot that draws water gets into the resin absorption system;

7., distillationization material pot material, distillation temperature is no more than 140 ℃, the distillation pressure-0.25～0MPa.

Compared with prior art, the process for refining of o-NP of the present invention, beneficial effect shows:

1, per 10 tons of waste water reclaim the 100kg o-Nitrophenyl methyl ether more, reduce adjacent amino phenylate production cost.

2, add charcoal absorption, improve the purity of o-NP, improve more than 99% by original content less than 95%.

3, regeneration of activated carbon is further extracted adjacent nitre methyl-phenoxide, and the gac reusable edible simultaneously, improves the o-Nitrophenyl methyl ether recovery.

4, original technology must could be purified through rectifying, existing purity, save energy and the equipment that just can improve o-NP through distillation.

5, the result of the more original technology of waste water COD reduces half, and impurity is by charcoal absorption, and foreign matter content significantly reduces, and helps resin absorption and handles waste water.

Embodiment

Below in conjunction with embodiment, the present invention is described further.

The process for refining of o-NP comprises the steps:

1., methyl ether oxidizing reaction mother liquor water is squeezed into storage tank, utilize the condensing surface cooling that circulates, temperature drops to below 30 ℃;

2., leave standstill 1 hour (layering is comparatively obvious), in, upper water squeezes into Decolouring pot; Lower floor's material can be returned oxidation system, reclaims o-Nitrophenyl methyl ether;

3., in Decolouring pot, add 1% powdered carbon, be warming up to 60 ℃, decoloured 1 hour;

4., the qualified back of decolouring (detecting indexs such as colourity), destainer carries out press filtration through pressure filter, the filter residue gac goes out o-Nitrophenyl methyl ether with methanol extraction, gac reclaims, recycling;

5., filtrating is squeezed into the acidifying pot, drip the vitriol oil, control pH value reaches 3, stopping acidification; Cool to 25 ℃ after the acidifying, o-NP is fully separated out;

6., under whipped state, squeeze into acidizing fluid and take out hopper, take out changing over to of hopper material material pot, lower layer of water gets into the pot that draws water, the water of the pot that draws water gets into the resin absorption system;

7., distillationization material pot material, distillation temperature is no more than 140 ℃, the distillation pressure-0.25～0MPa.

Above content only is to give an example and explanation to what operating procedure of the present invention was done; Under the technician in present technique field described specific embodiment is made various modifications or replenish or adopt similar mode to substitute; Only otherwise depart from the design of invention; Perhaps surmount the defined scope of these claims, all should belong to protection scope of the present invention.

Claims (1)

1. the process for refining of o-NP is characterized in that, comprises the steps:

1., methyl ether oxidation mother liquor water is squeezed into storage tank, utilize the condensing surface cooling that circulates, temperature drops to below 30 ℃;

2., left standstill 1 hour, squeeze into Decolouring pot to water at the middle and upper levels; Lower floor's material can be returned oxidation system, reclaims o-Nitrophenyl methyl ether;

3., in Decolouring pot, add 1% powdered carbon, be warming up to 60 ℃, decoloured 1 hour;

4., the decolouring qualified after, destainer carries out press filtration through pressure filter, the filter residue gac goes out o-Nitrophenyl methyl ether with methanol extraction, again recovered carbon;

5., filtrating is squeezed into the acidifying pot, drip the vitriol oil, control pH value reaches 3, stopping acidification; Cool to 25 ℃ after the acidifying, o-NP is fully separated out;

6., under whipped state, squeeze into acidizing fluid and take out hopper, take out changing over to of hopper material material pot, lower layer of water gets into the pot that draws water, the water of the pot that draws water gets into the resin absorption system;

7., distillationization material pot material, distillation temperature is no more than 140 ℃, the distillation pressure-0.25～0MPa.