Dye diffuser production to achieve green desalination

The cyclic extraction and desalination process of naphthalene derivative sulfonate formaldehyde condensate jointly developed by Beijing University of Chemical Technology and Anyang Teachers College was successfully developed. At present, the process has been carried out in a 5 cubic meter extraction kettle in an auxiliary company in Henan Province. The process is stable, the product quality is up to standard, and it has industrial conditions. The process completely solves the industry defects of the traditional process due to the use of lime to produce a large amount of calcium sulfate waste residue, and realizes the recycling and zero discharge of process wastewater.

The new process adopts a fully enclosed green extraction scheme. By simply adjusting the pH value of the system and utilizing the solubility of naphthalenesulfonic acid (salt) in the organic phase and the aqueous phase under different acidities, the separation of sulfate and sulfonate is achieved, and the water is lost to the water. A small amount of the organic phase of the phase is returned to the extraction system after being recycled by the wastewater and drying dehydration. The process is a fully enclosed system, without "three wastes" discharge, no need to supplement the organic phase, excess sulfuric acid forms a by-produced sodium sulfate, and the sodium sulfate content of the product naphthalenesulfonic acid formaldehyde condensate reaches less than 1%.

Disperse dyes, reactive dyes and other dyes with MF, NNO diffusing agents, as well as NNO dispersants for pesticides, electroplating and other industries, the chemical composition of which is naphthalene or its derivatives sulfonate formaldehyde condensate, industrially from naphthalene and its The derivative is produced by sulfuric acid or fuming sulfuric acid sulfonation, formaldehyde condensation, neutralization, lime desalting, drying and the like. Since the sulfonation process requires the use of excess sulfuric acid, in order for the sodium sulfate in the product to meet the application standards, the process must use lime to remove excess sulfuric acid, thereby producing a large amount of calcium sulfate waste. The traditional method of disposing calcium sulphate waste is to transfer the cement directly to the cement enterprise. Since the waste residue contains trace organic matter, it is recognized as solid hazardous waste. The implementation of the new Solid Waste Law prohibits such disposal.