US 12,404,190 B2
Resource utilization-oriented treatment method for spent electroless nickel plating bath
Shanting Li, Guangdong (CN); Kan Tan, Guangdong (CN); Wenbin Xu, Guangdong (CN); Yanhua Zhang, Guangdong (CN); Yongjun Xiao, Guangdong (CN); Xinglin Guo, Guangdong (CN); and Long He, Guangdong (CN)
Assigned to Dongjiang Environmental Company Limited, Shenzhen (CN)
Appl. No. 17/918,369
Filed by Dongjiang Environmental Company Limited, Guangdong (CN)
PCT Filed Dec. 30, 2020, PCT No. PCT/CN2020/141208
§ 371(c)(1), (2) Date Oct. 12, 2022,
PCT Pub. No. WO2022/141147, PCT Pub. Date Jul. 7, 2022.
Prior Publication US 2023/0322593 A1, Oct. 12, 2023
Int. Cl. C02F 1/66 (2023.01); C02F 1/52 (2023.01); C02F 1/72 (2023.01); C02F 101/20 (2006.01); C02F 103/16 (2006.01)
CPC C02F 1/66 (2013.01) [C02F 1/5245 (2013.01); C02F 1/725 (2013.01); C02F 2101/20 (2013.01); C02F 2103/16 (2013.01); C02F 2209/02 (2013.01); C02F 2209/05 (2013.01); C02F 2209/06 (2013.01); C02F 2209/44 (2013.01); C02F 2305/026 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A resource utilization-oriented treatment method for a spent electroless nickel plating bath, comprising the following steps:
at step S1, oxidation de-complexation: adjusting the pH of the spent electroless nickel plating bath and adding hydrogen peroxide and then stirring to uniformity, and then moving to an oxidation tower for aeration for performing oxidation reaction of 2 to 5 h to obtain an acid reaction solution, wherein the oxidation tower is internally filled with a non-homogeneous Fenton catalyst;
at step S2, synchronous precipitation of nickel and phosphorus: adjusting the pH of the acid reaction solution and adding a precipitant, performing heating, aging, and filtering to obtain a first filtrate and a nickel phosphate product;
at step S3, secondary precipitation of nickel: adding a sodium hydroxide solution to the first filtrate to adjust pH to be greater than 10, and performing heating, aging, and filtering to obtain a second filtrate and a nickel hydroxide product;
at step S4, resource utilization of sodium salt: adding an acidity adjusting solution to adjust the pH of the second filtrate to be 7 to 8 and adjusting a conductivity, and then obtaining a third filtrate, wherein the third filtrate is treated by using a three-compartment bipolar membrane electrodialysis process to prepare a finished acid solution and a sodium hydroxide solution.