CHAPTER 5
CONCLUSION
Prom t h i s experim ent and w ith r e g a rd in g to n a tu re o f r e a c t io n media and tem perature as r e a c t io n p aram eters, n o n -p o la r s o lv e n t s are b e t t e r r e a c t io n media than p o la r ones (e xce p t m ethyl e t h y l ketone ) f o r r e a c t i v i t y o f sodium io n s i n e t h e r i f i c a t i o n a t b oth 2 6 + 2°c .and 44 + 2 °c . The r e a c t i v i t i e s o f sodium io n s i n e t h e r i f i c a t i o n o f c e l l u lo s e in v a r io u s r e a c t io n media are i n the fo llo w in g d e c re a s in g o r d e r s :
a t 26 + 2°c ร m ethyl e t h y l ketone (d.S . 0.6 4 3) , benzene
( D .s . 0.5 1 5)» to lu e n e (.จ .ร. 0.5 0 2) , cycloh exan e (d.S . 0.4 9 7), n-hexane (d.S . 0.4 9 4), acetone ( จ . 3. 0 .1 7 4 ), is o - p r o p y l a lc o h o l (d.s. 0.0 2 9), e t h y l a lc o h o l (d.s. 0.0 2 1) , n - p r o p y l a lc o h o l (d.s. 0 .0 2 0 ).
a t 4 4 + 2°c : m ethyl e t h y l ketone (d.s. 0.6 5 5) , benzene
(d.s. 0.๐4 2) , to lu e n e (d.s. 0.5 7 3)» n-hexane (d.s. 0.5 3 1)» cyclo h ex an e ( จ . ร . 0 .4 9 4 ), aceton e (d.s. 0 .0 8 7 ), e t h y l a lc o h o l (d.s. O.O8 3) , n -p ro p y l a lc o h o l (d.s. 0.0 2 9) , is o - p r o p y l a lc o h o l (d.s. 0.0 2 4) .
As re g a rd s to 4.1 , 4 . 2 and 4.3» the p ro d u c ts w ith D . s . h ig h e r than 0 . 7 can be o b ta in e d , w ith c e r t a i n r e a c t io n l i m i t a t i o n s (see
T a b le 9)» by u s in g m ethyl e t h y l ketone and by benzene as r e a c t io n medium.
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T a b le 9 L i s t o f e t h e r i f i c a t i o n p r o d u c t s w it h L . ร . h i g h e r th a n 0 . 7 0 0
L . ร . R e a c t io n tim e (d a y ) T e m p e ra tu re ( ° c )
R e a c t io n medium
0 .8 8 0 + 0*C1G 7 2 6 + 2 m e th y l e t h y l k e to n e
0 . 8 6 8 + 0 . 0 1 0 5 ff If If It
0 .7 8 S + 0 .0 0 9 3 If Il II II
0 .7 5 8 + 0 .0 1 1 7 44 ± 2 Il II It
0 . 7 0 7 + 0 . 0 0 0 7 2 6 + 2 b en zen e
A c c o r d i n g to 4*4> th e d e v i a t i o n o f D . ร . q u a n t i t y o f e t h e r i f i c a t i o n p r o d u c t s o c c u r s w it h d i f f e r e n c e i n p r e p a r a t i o n o f c e l l u l o s e . T h a t i s n a t u r e o f s o u r c e o f c e l l u l o s e u se d i s one o f r e a c t i o n param e
t e r s e n c o u n te r e d i n c o n s i d e r i n g th e B . ร . q u a n t i t y o f th e p r o d u c t s o b t a in e d .
H o w ever, m e th y l e t h y l k e to n e i s , t h u s , c o n s id e r e d as an e x c e l l e n t r e a c t i o n medium w it h h ig h r e a c t i v i t y o f sodiu m io n s and w it h the p r e f e r r e d p r o m o t io n f o r f u r t h e r e t h e r i f i c a t i o n u n d e r th e c e r t a i n r e a c t i o n c o n d i t i o n s .
In c o n c l u s i o n , i t i s , t h e r e f o r e , th e e x t e n t o f r e a c t i v i t y o f sodiu m io n s i n e t h e r i f i c a t i o n r e a c t i o n o f c e l l u l o s e and th e in d u c in g t e n d e n c y o f f u r t h e r e t h e r i f i c a t i o n do c l e a r l y depen d on s e v e r a l f a c t o r s in v o l v e d i n th e s y s te m . '‘ Such t y p i c a l f a c t o r s a r e t e m p e r a t u r e , r e a c t i o n medium, r e a c t i o n tim e and n a t u r e o f s o u r c e o f c e l l u l o s e . ^
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S in c e the marked d if f e r e n c e s i n the r e a c t i v i t y o f sodium io n s i n v a r io u s r e a c t io n c o n d it io n s a re known, the r e s u l t s o b ta in e d from t h i s stu d y are p o s s ib ly ca p a b le to a p p ly f o r i n d u s t r i a l problem sh o o t
in g , and f o r f in d in g out f u r t h e r econom ics and w o r t h ily p r a c t i c a l method o f p r e p a r a t io n i n the in d u s t r y o f c e l l u l o s e , c e l l u l o s e d e r i v a t i v e s and o th e r a l l i e d p ro d u c ts .
