At present, the commonly used methods for treating nickel-containing wastewater are: chemical precipitation (using hydroxide or sulfide as precipitant), electrolysis, ion exchange, adsorption and oxidation-reduction. Although the above methods are effective in removing nickel ions, they all face problems such as high treatment costs and easy secondary pollution. Therefore, choosing a suitable extraction method to treat electroplating wastewater has become a research focus.
Zhengzhou Tiei Extraction has developed a new CWL-M centrifugal extraction process based on a large amount of experimental data, which combines the synergistic extraction principle of di(2-ethylhexyl)phosphoric acid + methyl isobutyl ketone. The centrifugal extraction method is different from the traditional liquid liquid extraction method. It is a green extraction process system. The process system has the following characteristics:
- The method is simple to operate, low in cost and high in efficiency.
- The residual nickel ion concentration meets the standard.
- The quality of the stripping solution obtained is stable and can meet different production requirements.
Process flow of synergistic extraction of nickel from nickel plating wastewater
- Preparation of extractant: Preparation of di(2-ethylhexyl)phosphoric acid + methyl isobutyl ketone synergistic extractant.
- Extraction process: The extractant and nickel plating wastewater are put into the centrifugal extractor for extraction.
Due to the density difference between the aqueous phase (nickel-containing wastewater) and the organic phase (extractant) during the extraction process, the two phases are first mixed after entering the CWL-M centrifugal extraction equipment, and then separated under the action of centrifugal force to complete the mass transfer and phase separation process. The CWL-M centrifugal extractor is equipped with an enhanced mass transfer and phase separation device to further improve the extraction efficiency and separation effect. - Stripping process: Add the extract to the acid solution for stripping to obtain nickel-containing recovery. This step and the extraction process are both operated continuously using the centrifugal extractor.
By using an extractant to extract nickel ions from nickel plating waste liquid, nickel ions can be efficiently extracted from nickel plating waste liquid, and the nickel ion removal rate can reach more than 93%. The residual nickel ion concentration meets the national standard and will not cause pollution to the environment. On the other hand, the nickel ions in the extract are stripped by an acid solution to recover the nickel ions and obtain a nickel-containing recyclate.
By using the centrifugal extractor, the extraction section occupies a small area, has a good operating environment, a small amount of liquid stored in the equipment, and a reduced investment cost for the organic phase. At the same time, the equipment has a sealed connection and a good operating environment, which can avoid secondary pollution.
Welcome contact us for more details.
Email: sales@tieiextraction.com
Whatsapp: +86 19069612820
