APPENDIX
SUGGESTED EXTRACTION PROCESSES

From the several possible methods for extracting metals and oxygen from the lunar and asteroidal resources, the following are considered best suited for nonterrestrial conditions:

1. Carbochlorination of lunar plagioclase concentrate in conjunction with Alcoa electrolysis for Al
2. Carbo chlorination of lunar ilmenite concentrate followed by Ca reduction of TiO₂ and subsequent reduction of Fe₂ O₂ by H₂ for Ti and Fe, respectively
3. Silicothermic reduction of asteroidal olivine concentrate for Mg
4. Methanation of CO and electrolysis of H₂ O and/or solidstate electrolysis of gas mixture containing CO, CO₂ and H₂O for oxygen.

• table 3
• table 4
• table 5
• table 6
• table 7

TABLE 3 .-REACTIONS OF INTEREST IN METAL AND OXYGEN EXTRACTION PROCESSES

1. Al2O3(s) + 3C(s) + 3CL2 (g) 2AlCl3 (g) + 3CO(g)

2. CaO2 (s) + C(s) + Cl2 (g) CaCl2(s) + CO(g)

3. SiO2(s) + 2C(s) + 2Cl2(g) SiCl4(g) + 2CO(g)

4. CaO Al2O3 2SiO2(s) + 8C(s) + 8Cl2(g) 2AlCl3(g) + CaCl2(g) + 2SiCl4(g) + 8CO(g)

5. FeTiO3(s) + 3C(s) + 3/2Cl2(g) FeCl3 + TiO2(s) + 3CO(s)

6. FeCl3(s) FeCl3(g)

7. FeCl3(s) + 3/2O2(g) 2Fe2O3(s) + 3Cl2(g)

8. Fe2O3(s) + 3H2(g) 2Fe(s) + 3H2O(g)

9. Fe2O3(s) + 3CO(s) 2Fe(s) + 3CO2(g)

10. TiO2(s) + 2Ca(s) Ti(s) + 2CaO(s)

11. Mg2SiO4(s) + 4CaO(s) + Si(s) 2Ca2SiO4(s) + 2Mg(g)

12. 2CO(g) CO2(g) + C(s)

13. Co(g) +2H2(g) CH4(g) + H2O(g)

14. H2(g) + 1/2 O2(g) H2O(g)

TABLE 4 .-THERMODYNAMIC DATA FOR SOME PERTINENT REACTIONS IN METAL AND OXYGEN EXTRACTION PROCESS

Reaction no.	Temperature K	Go Kcal	Ho Kcal	K	Partial pressure of species (Pi = 1 atm)
					Gaseous species	Pi	Gaseous species	Pi	Gaseous species	Pi
1	900	-62.2	37.7	1.26X1015	AlCl3	~0.4	CO	~0.6	Cl2	3.0X10-6
	1000	-73.3	37.7	1.07X1015	AlCL3	~0.4	CO	~0.6	Cl2	1.4X10-6
2	900	-73.3	-63.4	6.5X1017	-	-	CO	~1.0	Cl2	1.6X10-18
	1000	-74.4	-63.4	1.8X1016	-	-	CO	~1.0	Cl2	5.5X10-17
3	900	-41.5	6.2	1.2X1010	SiCl4	~0.333	CO	~0.667	Cl2	3.5X10-6
	1000	-48.8	6.2	1.7X1010	SiCl4	~0.333	CO	~0.667	Cl2	3.0X10-6
4	900	-190.6	11.9	1.9X1046	SiCl4or AlCl3	~0.166	CO	~0.667	Cl2	2.3X10 -6
	1000	-213.1	11.9	3.7X1046	AlCl3	-	CO	~0.667	Cl2	2.0X10-6
5	1000	-69.2	-76	2.7X1033	FeCl3	0.25	CO	0.75	Cl2	5.3X10-21
	1100	-74.1	-76	2.7X1030	FeCl3	0.25	CO	0.75	Cl2	1.21X10-21
6	500	11.2	33.2	1.3X10-5	FeCl3	1.3X10-5	-	-	-	-
	600	6.7	33.2	3.8X10-3	FeCl3	3.8X10-3	-	-	-	-
7	500	-25.6	-8.6	1.5X1011	O2	3.6X10-8	-	-	Cl2	~1
	600	-29.0	-8.6	3.5X1010	O2	9.3X10-8	-	-	Cl2	~1
8	1000	-3.6	15.3	6.62	H2	0.348	-	-	H2O	0.625
	1200	-7.6	15.3	24.0	H2	0.257	-	-	H2O	0.743
9	1000	-5.9	-9.0	19.9	-	-	CO	0.27	CO2	0.73
	1200	-5.4	-9.0	94.7	-	-	CO	0.325	CO2	0.675
10	1200	-70.3	-81.3	6.3X1012	-	-	-	-	-	-
	1300	-69.4	-81.3	4.6X1010	-	-	-	-	-	-
11	1300	+7.7	64.7	5.2X10-2	Mg	0.23	-	-	-	-
	1500	-1.1	64.7	1.46	Mg	1.21	-	-	-	-
12	800	-7.3	-41.0	101.0	-	-	-	-	-	-
	1200	9.4	-41.0	1.92X10-2	-	-	-	-	-	-
13	1000	6.4	-54.6	3.9X10-2	-	-	-	-	-	-
	1200	8.6	-54.6	2.8X10-2	-	-	--	-	-	-
14	1000	-46.0	-59.3	1.16X1010	-	-	-	-	-	-
	1200	-43.4	-54.3	7.9X107	-	-	-	-	-	-

TABLE 5 .-THEORETICAL AMOUNTS OF RACTANTS AND PRODUCTS IN VARIOUS METAL EXTRACTION PROCESSES

Extraction process for:	Basis, 1 kg	Reaction	Reactants required, kg			Products formed, kg
Aluminum	Anorthite	4	CaOAl2O32SiO 2	C	Cl2	AlCl3	CaCl2	SiCl4a	CO
			(1)	(0.345)	(2.036)	0.956)	(0.399)	(1.221)	(0.805)
	Electrolyte	--	AlCl3	Alkalai and alkaline earth chlorides	Alkalai and alkaline earth chlorides	AL	CL2	-	-
			(0.05)	(0.95)	(0.95)	0.0101)	(0.00399)	-	-
Titanium and iron	Ilmenite	5	FeTiO3	C	Cl2	FeCl3	TiO2	-	CO
			(1)	(0.040)	(0.463)	(0.708)	(0.463)	-	(0.093)
		10	TiO2	Ca	-	CaO	Ti	-	-
			(0.463)	(0.463)	-	(0.650)	(0.277)	-	-
		7	FeCL3	O2	-	Fe2O3	Cl2	-	-
			(0.708)	(0.053)	-	(0.347)	(0.463)	-	-
		8	Fe2O3	H2	-	Fe	H2O	-	-
			(0.347)	(0.013)	-	(0.243)	(0.117)	-	-
Magnesium	Olivine	11	Mg2SiO4	CaO	Si	Ca2SiO4	Mg	-	-
			(1)	(1.594)	(0.200)	2.448)	(0.346)	-	-

^aIf SiCl₄ is suppressed, 0.775 kg of SiO₂ can be recovered.

TABLE 6 .-THEORETICAL HEAT REQUIREMENTS AND SENSIBLE HEATS FOR SOME REACTIONS IN METAL EXTRACTION PROCESSES

Extraction process for:	Reaction	Temperature, K	HT-H298 reactants, Kcal	Enthalpy of reaction H,oT, Kcal	Sensible heat in products HT-H298, Kcal
Al	4	1000	119.8	11.9	141.2
Ti	5	1100	37.4	-76.0	158.3
	10	1200	29.9	-51.5	31.4
Fe	7	600	17.8	-8.6	18.4
	8	1000	38.9	15.3	161.8
Mg	11	1500	115.6	64.7	178.7

TABLE 7 .-ILMENITE PROCESSING DETAILS^a

Year (SMF frame)	2	3	4	5	6
Ilmenite concentrate (X10-3tons/year)	16	40	61	81	81
Tubes in use	465	1160	1770	2350	2350
Rutile requirement, tons	7.4	18.4	28.1	37.3	37.3
Carbon requirement, tons/day	1.8	4.4	6.7	8.9	8.9
Chlorine requirement, tons/day	20.3	50.8	77.5	103	103
Ferric chloride produced, (X10-3tons/year)	11.3	28.3	43.1	57.3	57.3
Rutile produced, (X10-3tons/year)	7.4	18.5	28.2	37.5	37.5
Carbon monoxide produced tons/day	4.1	10.2	15.6	20.7	20.7
Tubes producing hematite	230	580	885	1175	1175
Oxygen requirement,btons/day	4.6	11.4	17.4	23.1	23.1
Hematite produced, (X10-3tons/year)	5.6	13.9	21.2	28.1	28.1
Hydrogen requirement, tons/day	0.58	1.44	2.20	2.92	2.92
Iron produced, (X10-3tons/year)	3.9	9.7	14.8	19.7	19.7
Calcium requirement,tons/day	20.3	50.8	77.5	103	103
Titanium produced, (X10-3tons/year)	4.4	11.1	16.9	22.4	22.4

^aBased on expirements in references 11 and 12.
^bRequirements should at least be doubled; 1 day in use, the next day being recycles.

Return to V-5

References

Table of Contents