ソーダ法による鉛鉱の直接製錬について

抄録

The authors investigated on the smelting of lead sulfide are by so-called “soda process”. The main results obtained are as follows.
(1) When lead sulfide are was heated with soda ash, pyrite cinder and coke at about 900°C, lead sulfide was reduced to lead and sulfur reacted with sodium carbonate, ferric oxide and carbon to form so-called “soda matte”. The over-all reactions are probably as follows.
PbS+Na₂CO₃+2C=Pb+Na₂S+3CO
2PbS+Fe₂O₃+3C=2Pb+2FeS+3CO
In this case, the reactions proceeded completely and most suitably, when the ratio of Na₂S to FeS obtained by above reactions was 54/46 by weight.
(2) For most suitable quantities of reducing agents, 1.2 equivalents to PbS in the are were required.
(3) The recovery of metallic lead increased with temperature. For instance, the yield was 97 percent at 1000°C.
(4) The purity of lead bullion was higher tha-n those obtained by the other processes.
(5) The results obtained from erosion tests for the refractories used for this process showed that Corhart Black and high chrome steel were more resistant against erosion than other refractories.