Continuous process for producing insoluble sulfur

Patent metadata

Field	Value
Publication number	US-11225411-B2
Application number	US-202016990422-A
Country	US
Kind code	B2
Filing date	Aug 11, 2020
Priority date	Aug 12, 2019
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

A method for producing insoluble sulfur, including: heating a sulfur to 200-700° C., quenching it with water, aqueous solution and other solvents, drying and solidifying the resulting substance at 40-80° C. for 3-15 h, to obtain an insoluble sulfur crude product; crushing the crude product in water into particles with a particle size of 50-400 meshes, wherein the water temperature is not higher than 80° C.; pumping the slurry of water and crude product into the upper part of an extraction column, pumping solvent into the lower part thereof; making the water and solvent from the top of the column flow into a separation tank to separate water phase and solvent phase, heating and evaporating the solvent phase to recover solvent and obtain soluble sulfur; heating and evaporating the insoluble sulfur and solvent from the bottom of the column to recover solvent and obtain purified insoluble sulfur.

First claim

The invention claimed is:

1. A continuous method for producing insoluble sulfur, comprising the following steps:
(1) heating a sulfur to 200-700° C., then quenching the sulfur with water, aqueous solution and other solvents as a quenching agent, and then drying and solidifying the resulting insoluble sulfur at 40-80° C. for 3-15 h, to obtain a solid insoluble sulfur crude product containing 30-70% of insoluble sulfur;
(2) crushing the insoluble sulfur crude product obtained in step (1) in water in a pulverizer into particles with a particle size of 50-400 meshes, wherein a temperature of water is controlled to not higher than 80° C. during the crushing;
(3) purifying and refining the insoluble sulfur obtained in step (2) in an extraction column, wherein water and the insoluble sulfur crude product are pumped into an upper part of the extraction column, and a solvent is pumped into the lower part of the extraction column;
(4) making liquid flowing out from a top of the extraction column flow into a separation tank for water and solvent to separate a water layer and a solvent layer, wherein the solvent layer is heated and evaporated to recover the solvent and sulfur, while the water layer returns to the pulverizer;
(5) feeding the insoluble sulfur and solvent separated from the lower part of the extraction column in step (3) into a filter to separate the solvent out;
(6) heating and evaporating the insoluble sulfur filtered in step (5) to recover the solvent; and
(7) adding a filling oil into the insoluble sulfur obtained in step (6) to result in a mixture, and uniformly mixing the resulting mixture to prepare an oil-filled insoluble sulfur product.

2. The continuous method as claimed in claim 1 , wherein the solvent is CS 2 .

3. The continuous method as claimed in claim 1 , wherein the solvent is trichloroethylene.

Assignees

• Univ China Petroleum East China

Inventors

• Wang Yanzhen
• Song Chunmin
• Duan Hongling
• Zhang An
• Gao Li

Classifications

• C01B17/0248

  of particulate sulfur · CPC title

• C01B17/12 Primary

  Insoluble sulfur (mu-sulfur) · CPC title

• C01B17/0237

  Converting into particles, e.g. by granulation, milling · CPC title

• C01B17/0232

  Purification, e.g. degassing · CPC title

• C01P2004/60

  Particles characterised by their size · CPC title