The diffusivity of oxygen in liquid lead by electrochemical measurements
- PDF / 835,673 Bytes
- 6 Pages / 569 x 813.28 pts Page_size
- 36 Downloads / 241 Views
AND
ZENSAKU
KOZUKA
The oxygen diffusivity in liquid lead in the t e m p e r a t u r e r a n g e of 880 to 1135~ was d e t e r m i n e d u s i n g the following e l e c t r o c h e m i c a l cell with l i n e a r g e o m e t r y : N i - N i O I ZrO2(+CaO) I O in Liquid P b l ZrO2(+CaO) I FeO-Fe304 The u n s t e a d y diffusion of oxygen in liquid lead was caused by applying a p r e s e l e c t e d v o l t age b e t w e e n the F e O - F e a O 4 and liquid lead e l e c t r o d e s . The oxygen diffusivity in liquid lead was c a l c u l a t e d f r o m the change of the e l e c t r o m o t i v e force with t i m e b e t w e e n the NiNiO and liquid lead e l e c t r o d e s . The e x p e r i m e n t a l r e s u l t s for D o w e r e in close a g r e e m e n t with those of Szwarc et al. whose v a l u e s w e r e l a r g e r by one o r d e r of m a g n i t u d e than those of the other i n v e s t i g a t o r s . The r e s u l t s of our e x p e r i m e n t s give the r e l a t i o n : D O= 14.8 / + 6 . 2 ~ • 10_4 /-4660+ \ - 4.4 / exp \ ~
2 5 6 0 ) cm2/s.
Based on the p r e s e n t data and the r e l i a b l e data for s o m e other liquid m e t a l s , the r a t i o of the oxygen diffusivity to the s e l f - d i f f u s i v i t y of the solvent was found to be c o r r e l a t e d with the s t a n d a r d free e n e r g y change for d i s s o l u t i o n of oxygen in the liquid m e t a l . T H E oxygen diffusivities in s o m e liquid m e t a l s have cible at a given d i s t a n c e f r o m the above c r u c i b l e . By b e e n m e a s u r e d u s i n g an e l e c t r o c h e m i c a l cell e m p l o y the p r e s e n t e x p e r i m e n t a l method, the l o c a l oxygen a c ing a s t a b i l i z e d z i r c o n i a e l e c t r o l y t e and a p r o c e d u r e tivity was e s t a b l i s h e d by the e l e c t r o m o t i v e f o r c e m e a different f r o m that which R i c k e r t and E1 Miligy ~ f i r s t s u r e m e n t . Any d e s i r e d oxygen c o n c e n t r a t i o n over a v e r y wide c o n c e n t r a t i o n r a n g e can be e a s i l y obtained used for the m e a s u r e m e n t of the oxygen d i f f u s i v i t i e s in liquid s i l v e r and copper. Two different e l e c t r o by c o u l o m e t r i c t i t r a t i o n . c h e m i c a l p r i n c i p l e s w e r e applied for the m e a s u r e Some r e s u l t s for the oxygen diffusivity in liquid leadS'9-*2were v e r y s c a t t e r e d (10 -~ ~ 10 -6 cm~/s at m e n t . F i r s t l y , the oxygen potential at the m e t a l about 800~ Recently, P a r l e e et al.*~ -~s have r e e l e c t r o l y t e i n t e r f a c e can be fixed by applying a p r e s e l e c t e d voltage to a cell so that the u n s t e a d y diffuported the c o r r e l a t i o n b e t w e e n the d i f f u s i v i t i e s of sion of oxygen in liquid m e t a l is effected. The oxygen hydrogen and n i t r o g e n in liquid m e t a l s and t h e r m o d y n a m i c functions. We a r e i n t e r e s t e d in e x a m i n i n g diffusivity can be e s t i m a t e d f r o m the chang
Data Loading...
