134:
The titanium produced by the Hunter process is less contaminated by iron and other elements and adheres to the reduction container walls less than in the Kroll process. The titanium produced by the Hunter process is in the form of powder called sponge fines. This form is useful as a raw material in
94:
The Hunter process was conducted in either one or two steps. If a single step was used the reaction equation is as above. Because of the large amount of heat generated by the reduction using sodium compared to using magnesium, and the difficulty in controlling the vapor pressure of liquid sodium, a
143:
produced by the Kroll process. Thus it is difficult to separate the NaCl from the titanium using distillation in an efficient manner. Therefore, the NaCl is removed by leaching in an aqueous solution. Recovering the byproduct (NaCl) from this aqueous solution is a process that requires additional
144:
energy. These issues motivated the discontinuation of the Hunter process in industry in 1993. Research into sodium reduction continues to this day due to the superior form and purity of the metal deposit produced when compared with the Kroll process.
138:
The main limiting factor for the usefulness of the Hunter process is the difficulty of separating the produced NaCl from the titanium. The vapor pressure of NaCl produced in the Hunter process is lower than the vapor pressure of
111:
in molten sodium chloride is transferred to a different container with the additional sodium required to form Ti. The two step processes proceeded according to the following two reactions:
285:
Takeda, Osamu; Uda, Tetsuya; Okabe, Toru H. (2014). "Chapter 2.9 - Rare Earth, Titanium Group Metals, and
Reactive Metals Production". In Seetharaman, Seshadri (ed.).
302:
197:
250:
Fray, Derek; Schwandt, Carsten (2017). "Aspects of the
Application of Electrochemistry to the Extraction of Titanium and Its Applications".
178:
213:
Heinz Sibum; Volker Günther; Oskar Roidl; Fathi
Habashi; Hans Uwe Wolf (2005). "Titanium, Titanium Alloys, and Titanium Compounds".
234:
323:
328:
67:(which resembles a metal). The Hunter process was used until 1993, when it was replaced by the more economical
36:
88:
91:
reduction of the oxygen. The Kroll process is now the most commonly used titanium smelting process.
63:
Prior to the Hunter process, all efforts to produce Ti metal afforded highly impure material, often
298:
267:
230:
193:
48:
28:
290:
259:
222:
185:
160:
84:
64:
47:(Na) in a batch reactor with an inert atmosphere at a temperature of 1,000 °C. Diluted
189:
294:
95:
two step process may instead be used. The two step processes consisted of reducing TiCl
317:
68:
35:
born in New
Zealand who worked in the United States. The process involves reducing
263:
271:
226:
76:
79:
instead of sodium. Both methods share the same initial step, obtaining TiCl
24:
164:
32:
159:
M. A. Hunter "Metallic
Titanium" J. Am. Chem. Soc. 1910, pp 330–336.
103:
with half the stoichiometric amount of sodium required to reduce TiCl
44:
71:, which was developed in the 1940s. In the Kroll process, TiCl
23:
was the first industrial process to produce pure metallic
289:. Vol. 3. Boston: Elsevier. pp. 1028–1029.
177:
51:is then used to leach the salt from the product.
215:Titanium, Titanium Alloys, and Titanium Compounds
219:Ullmann's Encyclopedia of Industrial Chemistry
8:
176:Schaschke, Carl (2014). "Hunter process".
130:(l, in NaCl) + 2Na(l) → Ti(s) + 2NaCl(l)
59:(g) + 4 Na(l) → 4 NaCl(l) + Ti(s)
152:
16:Industrial process producing titanium
7:
190:10.1093/acref/9780199651450.001.0001
180:A Dictionary of Chemical Engineering
295:10.1016/B978-0-08-096988-6.00019-5
14:
287:Treatise on Process Metallurgy
1:
27:. It was invented in 1910 by
264:10.2320/matertrans.MK201619
184:. Oxford University Press.
345:
227:10.1002/14356007.a27_095
221:. Weinheim: Wiley-VCH.
123:(l, in NaCl) + 2NaCl(l)
252:Materials Transactions
37:titanium tetrachloride
107:to Ti. Next, the TiCl
324:Industrial processes
165:10.1021/ja01921a006
135:powder metallurgy.
119:(g) + 2Na(l) → TiCl
329:Titanium processes
304:978-0-08-096988-6
199:978-0-19-965145-0
49:hydrochloric acid
29:Matthew A. Hunter
336:
309:
308:
282:
276:
275:
247:
241:
240:
210:
204:
203:
183:
173:
167:
157:
65:titanium nitride
344:
343:
339:
338:
337:
335:
334:
333:
314:
313:
312:
305:
284:
283:
279:
249:
248:
244:
237:
212:
211:
207:
200:
175:
174:
170:
158:
154:
150:
142:
129:
122:
118:
110:
106:
102:
98:
82:
74:
58:
42:
17:
12:
11:
5:
342:
340:
332:
331:
326:
316:
315:
311:
310:
303:
277:
242:
235:
205:
198:
168:
151:
149:
146:
140:
132:
131:
127:
124:
120:
116:
108:
104:
100:
96:
80:
75:is reduced by
72:
61:
60:
56:
40:
21:Hunter process
15:
13:
10:
9:
6:
4:
3:
2:
341:
330:
327:
325:
322:
321:
319:
306:
300:
296:
292:
288:
281:
278:
273:
269:
265:
261:
257:
253:
246:
243:
238:
232:
228:
224:
220:
216:
209:
206:
201:
195:
191:
187:
182:
181:
172:
169:
166:
162:
156:
153:
147:
145:
136:
125:
114:
113:
112:
92:
90:
86:
78:
70:
69:Kroll process
66:
54:
53:
52:
50:
46:
38:
34:
30:
26:
22:
286:
280:
255:
251:
245:
218:
214:
208:
179:
171:
155:
137:
133:
93:
89:carbothermic
85:chlorination
83:from ore by
62:
20:
18:
258:: 306–312.
318:Categories
236:3527306730
148:References
272:1345-9678
77:magnesium
25:titanium
99:to TiCl
43:) with
33:chemist
301:
270:
233:
196:
45:sodium
39:(TiCl
299:ISBN
268:ISSN
231:ISBN
194:ISBN
139:MgCl
126:TiCl
115:TiCl
87:and
55:TiCl
31:, a
19:The
291:doi
260:doi
223:doi
186:doi
161:doi
320::
297:.
266:.
256:58
254:.
229:.
217:.
192:.
307:.
293::
274:.
262::
239:.
225::
202:.
188::
163::
141:2
128:2
121:2
117:4
109:2
105:4
101:2
97:4
81:4
73:4
57:4
41:4
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.