公开(公告)号：US11697594B2

公开(公告)日：2023-07-11

申请号：US17764561

申请日：2021-01-16

Applicant: CENTRAL SOUTH UNIVERSITY

Inventor： Yanqing Lai ,  Zhongliang Tian ,  Kai Yang ,  Yifan Li ,  Peiyu Gong ,  Bo Hong ,  Jie Li

IPC: C01B32/205 ,  C25C3/08 ,  B09B3/70 ,  B09B3/40 ,  B09B101/15

CPC classification number: C01B32/205 ,  B09B3/40 ,  B09B3/70 ,  C25C3/08 ,  B09B2101/15

Abstract: A method for recycling spent carbon cathode of aluminum electrolysis includes the following steps: (1) crushing and sieving spent carbon cathode, to obtain carbon particles; (2) mixing the carbon particles with a sulfuric acid solution, to obtain a slurry A, and then performing pressure leaching, to obtain a slurry B; (3) evaporating and concentrating the slurry B until a mass percentage of water is lower than 8%, to obtain a slurry C; (4) adding concentrated sulfuric acid to the slurry C to obtain a slurry D, then roasting the slurry D at 150-300° C. for 0.5-10 h, and then roasting at 300-600° C. for 0.5-8 h, to obtain the roasted carbon; and calcining the roasted carbon at a high temperature, to obtain the purified carbon, or mixing the roasted carbon with a leaching agent, and performing leaching, filtering, and washing, to obtain the purified carbon.

公开(公告)号：US12221366B1

公开(公告)日：2025-02-11

申请号：US18804147

申请日：2024-08-14

Applicant: Central South University

Inventor： Chenyang Zhang ,  Mingjun Han ,  Wei Sun ,  Jie Li ,  Wenjihao Hu ,  Heng Yu ,  Rong Wang ,  Siyuan Liu ,  Xiangsong Meng ,  Pan Chen

IPC: C02F1/52 ,  C01G49/12 ,  C02F1/66 ,  C02F101/20 ,  C02F103/34

Abstract: A method for recycling a copper-containing wastewater from a micro-etching is provided, including: modifying a FeS material with a monomer including both carboxyl and sulfhydryl, a crosslinking agent, and a stabilizing and dispersing agent to obtain a FeS-based pH-responsive material CMC-FeS@HS #SiO2 #COOH, adding the FeS-based pH-responsive material to weakly-acidic copper-containing wastewater from the micro-etching to allow a reaction, and conducting processes such as sulfide precipitation, exchange, adsorption complexation, and flocculation precipitation to finally obtain a precipitate with CuS as a main component. This method makes full use of the pH responsiveness and abundant surface active sites of the FeS-based pH-responsive material, and can control a recovery rate of copper ions in the wastewater at 99.8% or more merely by adjusting a pH value of the copper-containing wastewater from the micro-etching.