Method for recycling heavy metals in electroplating wastewater by using modified titanium nanotube

Abstract

The invention discloses a method for recycling heavy metals in electroplating wastewater by using a modified titanium nanotube. The method comprises the following steps: soaking a titanium nanotube in absolute ethyl alcohol for 12-48 hours, and drying at 60-80 DEG C to obtain the modified titanium nanotube; adjusting pH of electroplating wastewater to 2-7, and then carrying out settling separation or filtering to remove solid impurities; filling the modified titanium nanotube into a packing column, introducing the pretreated electroplating wastewater into the modified titanium nanotube packing column, and carrying out ion exchange till the titanium nanotube is saturated by adsorption; and putting the modified titanium nanotube which is saturated by adsorption into a sodium hydroxide aqueous solution, soaking for 6-18 hours, then filtering out the modified titanium tube, and drying the solution by distillation to obtain heavy metal substances. According to the method disclosed by the invention, the heavy metal ions in the electroplating wastewater are caught and then recycled by the modified titanium nanotube; the modified titanium nanotube which is used for multiple times can also be used as a denitration catalyst, which is favorable for emission reduction of nitric oxides and having multiple benefits.

Description

technical field

[0001] The invention belongs to the field of electroplating wastewater treatment, and in particular relates to a method for recovering heavy metals in electroplating wastewater by using modified titanium nanotubes. Background technique

[0002] The electroplating industry is one of the three major polluting industries in the world. my country's electroplating industry is currently developing rapidly, and there are about 10,000 electroplating factories nationwide. The electroplating industry produces about 4 billion m of wastewater every year 3 , causing serious environmental pollution problems, seriously restricting its sustainable development in our country. Electroplating wastewater contains nickel, copper, chromium, zinc, cadmium, silver and other heavy metal ions, which are difficult to biodegrade in the environment and easy to accumulate, so they can have long-term adverse effects on the environment and human health. How to completely eliminate the he...