Question

Which method is used in the refining of Titanium metal ?
A.Zone refining
B.Mond carbonyl
C.Frasch
D.Van Arkel

Answer 1

Hint: The method which should be used for the refining of a particular metal should be chosen on the basis of the kind of metal we are refining . Like titanium is a metal which can form a volatile compound .

Complete step by step answer:
After extraction of metals from their ore the next process is refining .
Titanium is a metal which can form a volatile compound with a suitable reagent , and the volatile compound produced is easily decomposable for the easy recovery of the metal .
These are the required conditions for vapour phase refining and so the method used for the refining of titanium is Van Arkel method as titanium has the conditions needed for it .
Van Arkel method is used for preparing ultra - pure metals by removing all the oxygen and nitrogen present in the form of impurity in titanium . In this method , crude titanium is heated in an evacuated vessel with iodine at 523K . The covalent titanium tetraiodide thus formed is separated . It is then decomposed by heating over a tungsten filament at 1700K to give pure titanium .
$Ti(s) + 2{I_2}(g)\xrightarrow{{523K}}Ti{I_4}(g)$
$Ti{I_4}(g)\xrightarrow{{1700K}}Ti(s) + 2{I_2}(g)$
Hence , option D is correct .


Note:
Refining is an important process after extraction because the crude metals obtained from the ores contain many impurities and hence they should be removed which is done by refining .