Bariy x l or i d xl orkal si y usuli b il an olish u c h u n m a y d a l a n g a n bariy
va ba r i y ni ng m i q d o r i d a n 13— 15% k o ‘m i r q o ‘shilib a y lanuvc hi si li nd
rik p e c h g a yu b or i l ad i.
Ma s s a p e c h d a 3 0 —40 m i n u t d a v o m i d a q i zdi ri la di , s o ‘n g ra p e c h
ga kalsiy x l o r i d n i n g t o ‘y i n g a n e r i t m a s i ( 8 0 0 —900 g/Z C a C l 2) q o ‘shi -
ladi kalsiy x l o ri dn i ng m i q d o r i b a r iyni ng mi qd o ri ni 4 8 —4 9 %
ni tashkil
q i ladi . M a s s a 1, 5—2 d a v o m i d a 7 7 0 — 780°C d a r a j a d a qi zd i r i l ad i,
n at i j a d a suv b u g ‘i p a r c h a l a n a d i , a r a l a s h m a suyul adi . T e m p e r a t u r a
9 0 0 —95 0 °C g a c h a k o ‘t a r i l g a c h , er ig a n m as sa k o ‘p i ra b o shl aydi , 1 —
1,5 s o a t d a n s o ‘ng r e aksi ya t a m o m b o ‘ladi. H a r o r a t 1000— 1100°C
ga k o ‘t a r i l ga n da n s o ‘ng massa bi r jinsli b o ‘lib m a h s u l o t tayyor b o ‘ladi.
P e c h davriy ishlagani sababli bir sikl 4 —5 soat d a v o m etadi. Q o t i s h m a
sovitiladi va q u yi da gi t a r ki bg a ega b o ‘ladi: 5 5 —6 0 % B a C l 2, 4 — 12%
C a O , , 4 % y a q i n C a S , 3% B a S 0 4, 0 , 5 % BaS, 6 —8%
reaksiyaga
k i r i s h m a g a n k o ‘m i r va b o s h q a a r a l a s h m a l a r — B a C 0 3, F eS , SiO,
s ovi gan q o t i s h m a m a y d a l a n i b B a C l , ni a r a l a s h m a l a r d a n aj ratib olish
u c h u n m a x s u s e r it uv ch i a p p a r a t d a issiq suv b i l a n ishlanadi. E r i t m a
e r i m a g a n q o l d i q d a n s en t r i f ug a y o r d a m i b il an aj ra t ib ol in ad i. E r i
m a g a n q o l d i q n i n g 20% ga yaqini C a S va 8— 10% B a S 0 4 tashkil qilgan
b o ‘lib m a x s u s h o v u z g a t a s h l an a d i .
T a r k i b i d a 3 0 0 —350 g/Z B a C l , ga ega b o ‘lgan e r i t m a l o yq a l i kd an
tindir i l ib b u g ‘latish j a r a y o n i g a y u bor i ladi va s o ‘n g r a sovitilib kristal
lanadi. Bu j a r a y o n l a r xuddi t uz kislotasi usuli kabi
bir xil qur i lma l ar da
bajariladi. Xl or ka lsi y us ul i ni ng t uz kislotasi usuliga ni s b a t an afzalligi
t e x n o l o g i y a n i n g soddal igi , c h u n k i b ar i t n i q a yt a r i sh va a l ma s hi n i sh i
j a r a y o n i b i r b o s q i c h d a — b i r a p p a r a t d a ketadi. Xlor ka lsi y us ul ining
k a m c h i l i g i s h u n d a k i , b u n d a o l t i n g u g u r t b i r i k m a l a r i i s h l a t i l m a y
t a s h l an a d i .
T u z
kislotasi u s ul i da esa, ajralib c h i q q a n H 2S o lt in g ug u r t ga yoki
S O , ga q a d a r q a y t a i shl anadi va o l t i n gu gu r t b i r i k m a l a r i d a n t o ‘liq
foyd al an i l a di .
9.4. X R O M T U Z L A R I
X r o m t uzlar i, ayni qsa i kki xrom kislotasining nat riy va kaliy tuzlari
x r o m p i k n o m i bilan atalib s a n o a t d a j u d a kat ta a h a m i y a t g a ega. X r o m
tuzlari teri, t o ‘q im ac h i l i k s a n o a t i d a , turli mi ne r a l va or g an i k b o ‘y o q -
lar t a y y o r l a s h d a ishlatiladi. Q i s m a n y o g ‘ s a n o a t i d a , q o g ‘o z
ishlab
c h i q a r i s h , e l e k t r t e x n i k a va f ot og r a f i y ad a q o ‘llaniladi.
X r o m oksi di b o ‘yo q t a y y o r l a s h d a , turli a s h y o l a r n i b o ‘y a s h da ,
shisha va ke r ami ka sanoa tl ari da, yo g ‘ni t ozal ashda va metal larni xr om
bilan q o p l a s h d a q o ‘llaniladi.
389
X r o m b i r i k m a l a r i n i s i n t e z q il i s hd a x o m a s h y o si fat ida t a b i a t d a
u c h r a y d i g a n x r o m l i k t e m i r - x r o m i t r u d a s i d a n f oy d a l a n i l a d i . X r o m i t
F e O • C r 20 3 yoki F e ( C r 0 2) 2 e r i m a y d i g a n H C r 0 2 k i s l ot as in i n g bi ri k-
masi de s a b o ‘ladi. X r o m rudasi 3 5 —4 5 % C r 20 3e g a b o ‘lib,
bir q i sm
t e m i r ikki oksidi ma g ni y va a l u m i n i y oksidi b i lan a l m a s h i ng a n boMishi
m u m k i n . S h u n i n g u c h u n t a b i i y x r o m m i n e r a l i n i n g f o r m u l a s i n i
q uy d ag i ch a :
( F e " \ M g " ' ) 0 • ( C r " \ Al 2" \ F e 2" ' ) 0 3
X r o m a t d a t e m i r n i n g x r o m g a n i s b a t a n 1:1 d a n 1:3 g a c h a b o ‘lishi
m u m k i n .
X r o m i d kislota y o r d a m i d a p a r c h a l a s h j a r a y o n i sust ke t ga n i s a
babli ki sl ota bilan q ay t a ishlash s a n o a t d a q o ‘l la n i l m a y d i . X r o mi t
a s os a n i s h q o r b i r i k ma l a r i i s h t i r o k i da o k s i d l a n i b , e r u v c h a n b i r i k m a -
l arga o 't k a z i l a d i .
X r o m i t n i k u yd ir i s h, s o d a i s h t i r o k i d a h a v o n i n g
k is lor odi bilan
x r o m n i o k si dl a s hg a a sosl anga n:
2 C r 20 3 + 4 N a 2C 0 3 + 3 0 2 = 4 N a 2C r 0 4 + 4 C 0 2
(1)
X r o m i t n i oks i d l an is h u m u m i y t e n g l a m a s i n i q u y i d a g i c h a tasav-
v u r qilish m u m k i n :
4 ( F e O • C r 20 3) + 8 N a 2C 0 3 + 7 0 2 = 8 N a 2C r 0 4 + 2 F e 20 3 + 8 C 0 2 (2)
Re a ks iya (2) ikki b o s q i c h d a ketib 1- b o s q i c h d a x r o m i t nat ri y hosil
b o ‘lib f a q a t g i n a t e m i r oksi dl an ad i:
4 ( F e O • C r 20 3) + 4 N a 2C 0 3 + 0 2 =
= 4 ( N a 20 • C r 20 3) + F e 20 3 + 4 C 0 2
2 - b o s q i c h d a x r o m oksidi o k s i dl a n ib x r o m i t x r o m a t g a ayl ana di :
4 ( N a 20 • C r 20 3) + 4 N a 2C 0 3 + 6 0 2 = 8 N a 2C r 0 4 + 4 C 0 2
(2) r e aksi ya b o ‘y i c h a hosil b o ‘lgan F e 20 3 r u d a d ag i a r a l a s h m a l a r
( C a O , M g O va S i 0 2) b il an re aksi yaga kirishib f e rr i tl ar va ferrosili-
k at la r hosil kiladi.
O k s i d l o v c h i k u y d i r i s h j a r a y o n i a y l a n u v c h i q u v u rl i p e c h l a r d a
1100— 1150°C darajali t e m p e r a t u r a d a ketadi. Bu s h a r o i t d a reaksiya
u c h t a faza o ‘rtasida, y a ’ni q a t t i q ( x r o m i t ) , g a z ho la t i da g i h av on i
( h a v o n i n g ki slorodi) va s u y u q ( s od a) ket adi.
9 . 2 - r a s m d a kel t i r i l g a n id ek s o d a n i n g er ish n u q t a s i 855°C, x r o m a t
na t ri yn i ki — 792°C, u l a r 655°C da r aj a s i da e r u v c h a n t a r k i b d a 62, 5
3 9 0