Green process for recovering yellow phosphorus from phosphorus mud

Abstract

The invention discloses a green process for recovering yellow phosphorus from phosphorus mud. The process comprises the following steps: step 1, putting the phosphorus mud into warm water to completely immerse the phosphorus mud in the water; step 2, adding ethanol, performing stirring, and controlling reaction temperature at 44.1-78.4 DEG C; step 3, after standing is completed, allowing a stratified liquid to appear, and respectively taking an upper-layer, middle-layer and lower-layer material; step 4, performing recycling on the liquid yellow phosphorus in the middle layer, and performing storage; step 5, washing the black residues in the lower layer by using hot water, and collecting a washing liquid; and step 6, performing extraction on the washing liquid by using ethanol, and collecting the liquid yellow phosphorus. When the process provided by the invention is adopted to recover the yellow phosphorus, the recovery rate of the yellow phosphorus is improved; and the process for recovering the yellow phosphorus is a green process, and has no secondary pollution.

Description

technical field [0001] The invention relates to the technical field of yellow phosphorus recovery, in particular to a green process for recovering yellow phosphorus from phosphorus mud. Background technique [0002] Yellow phosphorus, also known as white phosphorus, is a white to light yellow brittle waxy solid with a melting point of 44.1°C, a boiling point of 280°C, and a density of 1.82 g / cm 3 . White phosphorus is very active and must be stored in water. People will be poisoned and die if they inhale 0.1 gram of white phosphorus. White phosphorus will turn into red phosphorus when heated to 250°C or exposed to light in the absence of air. Red phosphorus is non-toxic and does not catch fire when heated above 400°C. Under high pressure, white phosphorus can be transformed into black phosphorus, which has a layered network structure, can conduct electricity, and is the most stable of phosphorus allotropes. [0003] At present, the recovery methods of phosphorus sludge c...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that the quality of recovered phosphoric acid is poor, the content of impurities is high, and the recovery rate is low, and about 25% of phosphorus pentoxide contained in the caustic acid residue cannot be absorbed.

[0005] There are two main methods of physical separation. One is to use organic solvents for extraction and separation. The organic solvents are generally carbon disulfide or benzene; Phosphorus sludge and yellow phosphorus are separated by filtration. This method can recover phosphorus sludge, but it is difficult to carry out production smoothly due to frequent blockage of filter cloth.

[0006] There are mainly the following types of chemical separation: one is to use soda ash or ammonia water to treat the silicon dioxide in the phosphorus sludge by alkali method, and then let the yellow phosphorus naturally condense and separate; the other is to use nitric acid and other oxidants to treat the phosphorus sludge and let the yellow phosphorus condense. These methods all use the method of external additives, causing secondary pollution to varying degrees

[0007] The prior art has the problem of serious secondary pollution or low recovery rate