METHOD FOR STABILIZING DITHIOCARBAMIC ACID BASED CHELATING AGENT

• Main Authors: OKUMURA MASATOSHI, FURUMOTO KATSUZO
• Format: Patent
• Language: English
• Published: 28.04.1998
• Edition: 6
• Subjects: ADHESIVES; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS; CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING ORPROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMISTRY; DISPOSAL OF SOLID WASTE; DYES; FIRE-FIGHTING; HUMAN NECESSITIES; LIFE-SAVING; MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FORELSEWHERE; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; PAINTS; PERFORMING OPERATIONS; POLISHES; RECLAMATION OF CONTAMINED SOIL SOIL; TRANSPORTING

PROBLEM TO BE SOLVED: To suppress the generation of harmful gas such as carbon disulfide and hydrogen sulfide at the time of preservating, transferring and using a heavy metal fixing agent consisting essentially of the aq. soln. in which monodithiocarbamate is dissolved by keeping the pH of aq. soln to a specified pH or above. SOLUTION: In the case when heavy metal in plant waste water, incineration ash from an incineration plant of city waste and industrial waste and ash, etc., discharged together with waste gas are detoxicated, the heavy metal fixing agent consisting essentially of the aq. soln. in which the monodithiocarbamate is dissolved is used to keep the pH of the aq. soln. to >=13. The monodithiocarbamic acid to be used is can easily be obtained by allowing amine to react with the carbon disulfide, and dimethlditihocarbamic acid, diethyldithiocarbamic acid, etc., are exemplified as the monodithiocarbamic acid. Sodium hydroxide, potassium hydroxide and lithium hydroxide are used preferably from the viewpoint of a solubility of the salt at the time of adjusting the pH.