CO Hydrogenation Over Cobalt Fischer-Tropsch Catalysts

	Abstract
	Acknowledgements
	List of Symbols and Abbreviations
	List of Figures and Tables
Section 1 899kb	1	Introduction				1
		1.1	The Fischer-Tropsch synthesis history			1
		1.2	Fischer-Tropsch synthesis today			2
		1.3	Objectives of the present work			4
		1.4	SPUNG			5
	2	Literature Review				7
		2.1	Fischer-Tropsch reaction mechanism			7
		2.2	Kinetics			12
		2.3	Cobalt catalysis			16
		2.4	Characteristics of the Co/Al₂O₃ system			17
			2.4.1	Cobalt spinals		18
			2.4.2	Effect of cobalt loading		19
			2.4.3	Effect of Calcination temperature		22
			2.4.4	Effect of cobalt precursor		23
			2.4.5	Promotion with noble metals		24
		2.5	Activity and selectivity			30
			2.5.1	Reduction extent and dispersion		30
			2.5.2	CO hydrogenation activity		32
			2.5.3	CO hydrogenation selectivity		34
			2.5.4	Activity and selectivity of bimetallic systems, compared to monometallic systems		37
Section 2 812kb	3	Experimental				43
		3.1	Catalysts preparation			43
		3.2	Temperature programmed reduction			46
			3.2.1	Principles		46
			3.2.2	Apparatus and procedure		47
		3.3	Pulse O₂ titration			49
			3.3.1	Principles		49
			3.3.2	Apparatus and procedure		49
		3.4	Volumetric Chemisorption of H₂ and CO			50
			3.4.1	Principles		50
			3.4.2	Apparatus and procedure		51
		3.5	Kinetic Investigations			53
			3.5.1	Apparatus and analytical equipment		53
			3.5.2	Procedure for kinetic experiments		53
	4	Results and Discussion				57
		4.1	Characterization of catalysts			57
			4.1.1	Temperature programmed reduction		57
				4.1.1.1	Influence of Calcination temperature	57
				4.1.1.2	Co₂O₄	64
				4.1.1.3	Platinum promotion	67
				4.1.1.4	Promotion with other noble metals	70
				4.1.1.5	Reduction at standard conditions	76
				4.1.1.6	Effect of chloride containing metal precursors	77
				4.1.1.7	Summary of the TPR results	81
Section 3 900kb			4.1.2	Extent of reduction determined by pulse O₂-tritration		84
			4.1.3	Volumetric chemisorption of H₂ and CO		88
				4.1.3.1	Effect of calcination temperature	88
				4.1.3.2	Effect of platinum and rhenium promotion	90
				4.1.3.3	Effect of chloride	99
				4.1.3.4	Dispersion and crystallite size	102
				4.1.3.5	Summary of the H₂ and CO adsorption measurements	109
		4.2	Activity measurements			110
			4.2.1	High temperature / 7 bara total pressure		110
Section 4 764kb			4.2.2	Low temperature / 1 bara total pressure		122
			4.2.3	Summary of the activity measurements		130
		4.3	Selectivity measurements			131
			4.3.1	High temperature / 7 bara total pressure		131
			4.3.2	Low temperature / 1 bara total pressure		141
	5	Conclusions				145
		5.1	Reduction behavior			145
		5.2	H2 and CO chemisorption			146
		5.3	Activity and Selectivity			147
	6	References				149
Section 5 263kb	Appendixes					157
	1	Metal loading in catalysts investigated				159
	2	Gases used in different apparatus				163
	3	Example of an adsorption isotherm and the calculation of dispersion from chemisorption of H₂ on Co/Al₂O₃B				165
	4	Volumetric chemisorption of H2 and CO, and dispersion calculated thereof				169
	5	BET surface and pore size distribution				173
	6	Formulas for calculation of activity and selectivity				181
	7	Product selectivity over the catalysts investigated				185