Electrochemical technologies for the on-site treatment of spent acid etchant have received great attention due their ease of operation and economic benefits. On the other hand

a large amount of Cl

2

is generated during the electrolysis process

which leads to potential environmental risks. In the present work

a novel threecompartment ceramic membrane flow reactor

including a cathode chamber

an anode chamber

and a gas absorption chamber was developed. The three chambers were divided by an Al

2

O

3

ceramic membrane and a breathable hydrophobic anode diffusion electrode (ADE). The Cl

2

evolution onset potential of the ADE was increased to 1.19 V from 1.05 V of the graphite felt

effectively inhibiting the chlorine evolution reaction (CER). The anode-generated Cl

2

diffused into the gas absorption chamber through the ADE and was eventually consumed by the H

2

O

2

adsorbent. Cu could be recovered without emitting chlorine due to the special structure of reactor. The current efficiency of copper precipitation and cathode reduction from Cu

2+

to Cu

+

reached 97.7% at a working cu

rrent of 150 mA. These results indicated that the novel membrane reactor had high potential for application in the copper recovery industry.