The Hydrogenation of Carbon Monoxide on Cobalt Catalysts

Section 1 463kb	1	Introduction
		1.1.	Coal conversion		1
		1.2.	The Fischer-Tropsch synthesis		3
		1.3.	Mechanisms proposed for the Fischer-Tropsch synthesis		4
		1.4.	The present state of the art		6
		1.5.	The aim and outline of this thesis		9
	2	Apparatus and Analysis
		2.1	Introduction		11
		2.2	The reaction system		11
			2.2.1	Flow scheme and reactor	12
			2.2.2	Analysis	13
			2.2.3	Characterization of the flow reactor	15
		2.3	The thermobalance		15
		2.4	The adsorption apparatus		16
		2.5	Definitions		17
			2.5.1	Rates	18
			2.5.2	Product distribution and selectivities	18
Section 2 522kb	3	Preparation and Characterization of the Catalysts
		3.1	Introduction		21
		3.2	Preparation of the catalysts		22
		3.3	Crystal structure of the catalysts		23
		3.4	Reduction of the catalysts		25
			3.4.1	Experimental	25
			3.4.2	Reduction by hydrogen	26
			3.4.3	Reduction by carbon monoxide	37
			3.4.4	Reduction of Co₃O₄ by mixtures of hydrogen and carbon monoxide	41
		3.5	Adsorption of hydrogen and carbon monoxide		42
Section 3 644kb	4	Activity and Selectivity of Cobalt Catalysts
		4.1	Introduction		44
		4.2	Standard experiments		45
			4.2.1	Cobalt on alumina	45
			4.2.2	Unsupported cobalt	46
			4.2.3	Discussion	48
		4.3	Influence of the hydrogen and carbon monoxide concentrations		49
		4.4	Influence of the temperature		54
			4.4.1	Cobalt on alumina	54
			4.4.2	Unsupported cobalt	56
		4.5	Influence of various catalyst treatments		57
			4.5.1	Cobalt on alumina	57
			4.5.2	Unsupported cobalt	63
		4.6	Other cobalt catalysts		65
		4.7	Discussion		66
Section 4 542kb	5	Formation of Carbonaceous Species
		5.1	Introduction		71
		5.2	Carbonization followed in the thermobalance		72
			5.2.1	Experimental	72
			5.2.2	Carbonization by carbon monoxide	73
			5.2.3	Carbonization by synthesis gas	80
			5.2.4	Discussion	82
		5.3	Flushing of the catalysts after the Fischer-Tropsch synthesis		85
			5.3.1	Introduction	85
			5.3.2	Experimental	86
			5.3.3	Flushing with hydrogen	86
			5.3.4	Flushing with helium	89
			5.3.5	Discussion	90
Section 5 512kb	6	Kinetics
		6.1	Introduction		92
		6.2	Reaction orders		93
			6.2.1	Experimental	93
			6.2.2	Overall orders	94
			6.2.3	Orders of various products	97
		6.3	Influence of the residence time		100
		6.4	Apparent energies of activation		101
		6.5	Discussion		103
			6.5.1	Overall orders of reaction	103
			6.5.2	Initiation	107
Section 6 478kb			6.5.3	Chain growth	115
			6.5.4	Reaction models	118
			6.5.5	Olefin-paraffin ratio	122
	7	Final Discussion
		7.1	Initiation		126
		7.2	Chain growth		130
		7.3	Termination		133
Section 7 550kb	Literature				135
	Appendix: Equations used in model calculations				143
	List of Symbols				147
	Summary				149
	Yhteenveto (Summary in Finnish)				151
	Samenvatting (Summary in Dutch)				153
	Curriculum				156
	Acknowledgements				157