A method for improving the decolorization rate of reactive dye printing wastewater

Abstract

The invention relates to a method for improving the decoloration ratio of wastewater from reactive dye printing, and belongs to the technical field of textile dyeing and printing. The method comprises the following steps of: adjusting the pH value of the wastewater from reactive dye printing to be neutral, slowly adding 0.5-2g / L calcium chloride and stirring to dissolve, and removing generated suspended solid by a millipore filter; adding 0.5-1g / L iso-decanol polyoxyethylene ether (the epoxy value is 7), and holding for 15 min after stirring uniformly, and at last photocatalytically decoloring the painting wastewater by using titanium dioxide. According to the method, the photocatalytic decoloration effect of the titanium dioxide on the wastewater from reactive dye printing can be effectively improved, and chromaticity of the printing wastewater can be reduced.

Description

technical field

[0001] The invention relates to a method for increasing the decolorization rate of reactive dye printing wastewater, in particular to improving the decolorization rate when titanium dioxide is used to photocatalyze reactive dye printing wastewater, and belongs to the technical field of textile printing and dyeing. Background technique

[0002] Reactive dyes have excellent performance and are widely used in the printing process of pure cotton fabrics such as direct dyeing, resist dyeing and discharge dyeing. When printing, reactive dyes, pastes, additives, etc. are formulated into a color paste with a certain viscosity. After printing on the fabric, it is dried, steamed or baked to make the dye react with the fiber. Usually, the color fixation rate of reactive dyes is only about 70%, and the unfixed dyes, pastes, auxiliaries, etc. need to be washed thoroughly through washing, soaping and other processes, and finally discharged with printing wastewater. [000...

Examples

Embodiment 1

[0009] Adjust the pH value of reactive red dye printing wastewater to neutral, slowly add 0.5g / L calcium chloride and stir to dissolve it, and then remove the generated solid suspension with a microporous membrane; add 0.5g / L calcium chloride under ultrasonic conditions Isomerize decanol polyoxyethylene ether (epoxy number is 7) and stir evenly for 15 minutes. Finally, the above printing wastewater is subjected to conventional titanium dioxide photocatalytic decolorization. After completion, the decolorization rate of the printing wastewater was determined to be 92%.

Embodiment 2

[0013] Adjust the pH value of reactive yellow dye printing wastewater to neutral, slowly add 1g / L calcium chloride and stir to dissolve it, then remove the generated solid suspension with a microporous membrane; add 0.5g / L isochloride under ultrasonic conditions Construct decanol polyoxyethylene ether (epoxy number is 7) and stir evenly for 15 minutes. Finally, the above printing wastewater is subjected to conventional titanium dioxide photocatalytic decolorization. After completion, the decolorization rate of the printing wastewater was determined to be 90%.

Embodiment 3

[0017] Adjust the pH value of the reactive blue dye printing wastewater to neutral, slowly add 2g / L calcium chloride and stir to dissolve it, and then remove the generated solid suspension with a microporous filter; add 1g / L isomeric Alcohol polyoxyethylene ether (epoxy number is 7) and stirred evenly for 15 minutes, and finally the above printing wastewater was subjected to conventional titanium dioxide photocatalytic decolorization. After completion, the decolorization rate of the printing wastewater was determined to be 88%.

technical field

[0001] The invention relates to a method for increasing the decolorization rate of reactive dye printing wastewater, in particular to improving the decolorization rate when titanium dioxide is used to photocatalyze reactive dye printing wastewater, and belongs to the technical field of textile printing and dyeing. Background technique

[0002] Reactive dyes have excellent performance and are widely used in the printing process of pure cotton fabrics such as direct dyeing, resist dyeing and discharge dyeing. When printing, reactive dyes, pastes, additives, etc. are formulated into a color paste with a certain viscosity. After printing on the fabric, it is dried, steamed or baked to make the dye react with the fiber. Usually, the color fixation rate of reactive dyes is only about 70%, and the unfixed dyes, pastes, auxiliaries, etc. need to be washed thoroughly through washing, soaping and other processes, and finally discharged with printing wastewater. [000...

Examples

Embodiment 1

[0009] Adjust the pH value of reactive red dye printing wastewater to neutral, slowly add 0.5g / L calcium chloride and stir to dissolve it, and then remove the generated solid suspension with a microporous membrane; add 0.5g / L calcium chloride under ultrasonic conditions Isomerize decanol polyoxyethylene ether (epoxy number is 7) and stir evenly for 15 minutes. Finally, the above printing wastewater is subjected to conventional titanium dioxide photocatalytic decolorization. After completion, the decolorization rate of the printing wastewater was determined to be 92%.

Embodiment 2

[0013] Adjust the pH value of reactive yellow dye printing wastewater to neutral, slowly add 1g / L calcium chloride and stir to dissolve it, then remove the generated solid suspension with a microporous membrane; add 0.5g / L isochloride under ultrasonic conditions Construct decanol polyoxyethylene ether (epoxy number is 7) and stir evenly for 15 minutes. Finally, the above printing wastewater is subjected to conventional titanium dioxide photocatalytic decolorization. After completion, the decolorization rate of the printing wastewater was determined to be 90%.

Embodiment 3

[0017] Adjust the pH value of the reactive blue dye printing wastewater to neutral, slowly add 2g / L calcium chloride and stir to dissolve it, and then remove the generated solid suspension with a microporous filter; add 1g / L isomeric Alcohol polyoxyethylene ether (epoxy number is 7) and stirred evenly for 15 minutes, and finally the above printing wastewater was subjected to conventional titanium dioxide photocatalytic decolorization. After completion, the decolorization rate of the printing wastewater was determined to be 88%.