CN101195595B - Method for recycling dimethyl sulfone and sodium nitrate from dimethyl sulfoxide waste slag - Google Patents

Abstract

The invention relates to a method for recovering dimethyl sulfone and sodium nitrate from dimethyl sulfoxide waste slag, which comprises arranging waste slag waste slag in a decompression autoclave at 120-160DEG C to decompress and distill, distilling out the dimethyl sulfoxide and dimethyl sulfone from dimethyl sulfoxide waste slag to be arranged into an another autoclave to be cooled to obtain crystallized solid, arranging the distilled dimethyl sulfoxide and dimethyl sulfone into enough hydrogen dioxide solution to be oxidized and dried in vacuum to obtain dimethyl sulfone product, dissolving leavings in water to be discharged, adding concentrated nitric acid into the filtered mother liquid to adjust pH till 2-3 and convert sodium nitrite to sodium nitrate, neutralizing over nitric acid via soda, to neutralize the mother liquid, heating the solution to 120-125DEG C, evaporating at normal pressure, cooling to 50-70DEG C, crystallizing, separating and drying to obtain sodium nitrate product. The invention can reduce discharge of industrial waste slag and reduce environment pollution, with simple process and low energy consumption.

Description

From the DMSO 99.8MIN. waste residue, reclaim the method for METHYL SULFONYL METHANE. and SODIUMNITRATE

Technical field

The present invention relates to the working method of a kind of METHYL SULFONYL METHANE. and SODIUMNITRATE, particularly a kind of method that from the DMSO 99.8MIN. waste residue, reclaims METHYL SULFONYL METHANE. and SODIUMNITRATE.

Background technology

The nitrogen peroxide oxidation style generates a large amount of oxynitride when producing DMSO 99.8MIN., after sodium hydroxide solution absorbs, generate and contain organic abraum salts such as a large amount of SODIUMNITRATE, Sodium Nitrite, METHYL SULFONYL METHANE. and small amounts of ether.Through detecting, the content of various materials is respectively in the abraum salt: METHYL SULFONYL METHANE. is 30-45%, and SODIUMNITRATE is 20-35%, and Sodium Nitrite is below 10%, and wherein Sodium Nitrite again can be through the nitrated SODIUMNITRATE that changes into.At present these waste residue utilization rates are low, most ofly do discarded the processing, contaminate environment not only, and be a kind of waste to material capable of using wherein.

Summary of the invention

The object of the invention is exactly that a kind of method that from the DMSO 99.8MIN. waste residue, reclaims METHYL SULFONYL METHANE. and SODIUMNITRATE will be provided, and it can process METHYL SULFONYL METHANE. and the SODIUMNITRATE with high additive value.

The objective of the invention is to realize like this: a kind of method that from the DMSO 99.8MIN. waste residue, reclaims METHYL SULFONYL METHANE. and SODIUMNITRATE, it may further comprise the steps:

A. separating of METHYL SULFONYL METHANE. and nitrate salt: place 120 ℃-160 ℃ decompression reaction kettle to carry out underpressure distillation in the DMSO 99.8MIN. waste residue; DMSO 99.8MIN. in the DMSO 99.8MIN. waste residue and METHYL SULFONYL METHANE. are steamed; Import in the other still cooling and promptly get the crystalline solid, the residue in the reaction kettle mainly contains SODIUMNITRATE and Sodium Nitrite;

B. METHYL SULFONYL METHANE. is refining: the hydrogen peroxide oxidation of adding capacity in the METHYL SULFONYL METHANE. that step a is distilled out and the DMSO 99.8MIN. can obtain the METHYL SULFONYL METHANE. product through vacuum-drying again;

C. SODIUMNITRATE is refining: the back that is dissolved in water of the residue among the step a is discharged, filters the mother liquor that obtains containing SODIUMNITRATE and Sodium Nitrite, again in mother liquor the adding concentrated nitric acid to be adjusted to pH be 2-3; Sodium Nitrite is converted into SODIUMNITRATE, and then with soda ash excessive nitric acid is neutralized, and makes mother liquor pH for neutral; This solution is heated to 120 ℃-125 ℃, and evaporation is cooled to 50 ℃ of-70 ℃ of crystallizations then under normal pressure; Separate, be drying to obtain the SODIUMNITRATE product.

Owing to adopt method of the present invention,, process METHYL SULFONYL METHANE. and SODIUMNITRATE product with high additive value so can from the DMSO 99.8MIN. waste residue, isolate material capable of using.The present invention has the discharging that reduces industrial residue, reduces the pollution to environment, and advantage such as the simple energy consumption of technology is little.

Embodiment

A kind of method that from the DMSO 99.8MIN. waste residue, reclaims METHYL SULFONYL METHANE. and SODIUMNITRATE, it may further comprise the steps:

A. separating of METHYL SULFONYL METHANE. and nitrate salt: place 120 ℃-160 ℃ decompression reaction kettle to carry out underpressure distillation in the DMSO 99.8MIN. waste residue; DMSO 99.8MIN. in the DMSO 99.8MIN. waste residue and METHYL SULFONYL METHANE. are steamed; Import in the other still cooling and promptly get the crystalline solid, the residue in the reaction kettle mainly contains SODIUMNITRATE and Sodium Nitrite;

B. METHYL SULFONYL METHANE. is refining: the hydrogen peroxide oxidation of adding capacity in the METHYL SULFONYL METHANE. that step a is distilled out and the DMSO 99.8MIN. can obtain the METHYL SULFONYL METHANE. product through vacuum-drying again;

C. SODIUMNITRATE is refining: the back that is dissolved in water of the residue among the step a is discharged, filters the mother liquor that obtains containing SODIUMNITRATE and Sodium Nitrite, again in mother liquor the adding concentrated nitric acid to be adjusted to pH be 2-3; Sodium Nitrite is converted into SODIUMNITRATE, and then with soda ash excessive nitric acid is neutralized, and makes mother liquor pH for neutral; This solution is heated to 120 ℃-125 ℃, and evaporation is cooled to 50 ℃ of-70 ℃ of crystallizations then under normal pressure; Separate, be drying to obtain the SODIUMNITRATE product.

Claims (1)

1. method that from the DMSO 99.8MIN. waste residue, reclaims METHYL SULFONYL METHANE. and SODIUMNITRATE is characterized in that it may further comprise the steps:

A. separating of METHYL SULFONYL METHANE. and nitrate salt: place 120 ℃-160 ℃ decompression reaction kettle to carry out underpressure distillation in the DMSO 99.8MIN. waste residue; DMSO 99.8MIN. in the DMSO 99.8MIN. waste residue and METHYL SULFONYL METHANE. are steamed; Import in the other still cooling and promptly get the crystalline solid, the residue in the reaction kettle mainly contains SODIUMNITRATE and Sodium Nitrite;

B. METHYL SULFONYL METHANE. is refining: the hydrogen peroxide oxidation of adding capacity in the METHYL SULFONYL METHANE. that step a is distilled out and the DMSO 99.8MIN. can obtain the METHYL SULFONYL METHANE. product through vacuum-drying again;

C. SODIUMNITRATE is refining: the back that is dissolved in water of the residue among the step a is discharged, filters the mother liquor that obtains containing SODIUMNITRATE and Sodium Nitrite, again in mother liquor the adding concentrated nitric acid to be adjusted to pH be 2-3; Sodium Nitrite is converted into SODIUMNITRATE, and then with soda ash excessive nitric acid is neutralized, and makes mother liquor pH for neutral; This solution is heated to 120 ℃-125 ℃, and evaporation is cooled to 50 ℃ of-70 ℃ of crystallizations then under normal pressure; Separate, be drying to obtain the SODIUMNITRATE product.