|
US1998935A
|
|
Acidproof composition
|
|
US1967265A
|
|
Process of reducing sulphur dioxide
|
|
US1981068A
|
|
Solution purification
|
|
US1941623A
|
|
Recovery of sulphur
|
|
US1967263A
|
|
Recovery of sulphur
|
|
US1967264A
|
|
Recovery of sulphur
|
|
US1945074A
|
|
Recovery of selenium
|
|
US1896178A
|
|
Reverberatory furnace
|
|
US1925339A
|
|
Electrodeposition of metals
|
|
ES119914A1
|
|
Improvements in the treatment of mattes.
|
|
ES119915A1
|
|
Improvements in the recovery of sulfur.
|
|
ES119913A1
|
|
Improvements in the recovery of sulfur.
|
|
ES119905A1
|
|
Improvements in sulfur recovery procedures.
|
|
US1883976A
|
|
Furnace charging device
|
|
US1893023A
|
|
Metallurgical apparatus
|
|
US1941606A
|
|
Metallurgical apparatus
|
|
US1899161A
|
|
Metallurgical apparatus
|
|
US1952727A
|
|
Froth flotation
|
|
US1863905A
|
|
Distributing and feeding apparatus
|
|
US1886903A
|
|
Treatment of matte
|
