| 摘要 |
A device for the electrolytic recovery of silver comprises a cylindrical electrolysis tank (10) made of plastic, against the inner wall surface (11c) of which rests an expendable cathode (30) which is formed into a hollow cylinder and consists of a sheet-type plastic carrier (31) to which a carbon sheet (32) has been applied by bonding. In the rim areas of the tank bottom (12) and the lower side of the removable top (14), projections (13, 15) are provided which extend into the tank (10) and have inclined portions (13a, 15a) extending away from the inner wall surface (11c) and behind which the lower rim portion (31a) and the upper rim portion (31b) of the carrier sheet (31) of the expendable cathode (30) are held, said carrier sheet extending further than the carbon sheet (32). At least one clamping bolt (40) of an electrically non conductive material is passed through a circular hole in the carbon sheet (32) and an associated larger circular hole in the carrier sheet (31) and is mounted and secured in a current-carrying contact bushing (36) arranged in tank wall (11). Owing to the different size of the circular holes, an annular area (32b) forming part of carbon sheet (32) is clamped between the head (40a) of clamping bolt (40) and the end face (36b) of contact bushing (36), which is located in the area of the inner wall surface (11c), and the cathode (30) is thus contacted and additionally held on the inner wall surface (11c). When the clamping bolt (40) is removed in the direction of the arrow, head (40a), which is shaped like a truncated cone, can be easily separated from the silver layer (52) deposited on the cathode. |
