Return to Books

The Conversion of Coal into Oils

by Dr. Franz Fischer

Authorized English Translation
with a Foreword and Notes
R. Lessing

London: Ernst Benn Limited
8 Bouverie Street, E.C.4

 Table of Contents

Section 1
Foreword i
Author's Preface ii
Contents v
List of Illustrations ix
List of Tables xi
Introduction 15
Section 2
I. Extraction by Solvents 20
(a) The Yield of Oil by Extraction 20
(b) Identification of Chemical Compounds in the Extracts 20
II. Production and Working-Up of Primary Tar 22
(a) Methods of Destructive Distillation of Fuels 22
(b) Special Laboratory Methods for the Production of Primary Tar 24
(c) Yields of Primary Tar From Coal and Peat 25
(d) Proximate Composition of Primary Tars 27
(e) The Temperatures Required for the Production of Primary Tar 28
Section 3
(f) Differentiation Between Various Primary Tars and Other Tars 30
(g) The Chemical Compounds Found in Primary Tar and in Primary Benzines 38
(h) The Liquor From Low-Temperature Carbonization 43
(i) Composition and Application of Low-Temperature Carbonization Gas 43
Section 4
(k) The Low-Temperature Benzine 46
(l) The Position of Primary Tar Between Coke-Oven Tar and Petroleum 49
(m) Semi-Coke 50
(n) The Heat Balance of Low-Temperature Carbonization 56
(o) The Development of Commercial Primary Tar Production 58
1. Distillation Apparatus with External Heating 59
Vertical Retorts 60
Section 5
Horizontal Retorts 64
Tunnel Kilns 68
Rotary Retorts 71
Retorts with Inner Lining 76
2. Internal Heating 76
Superheated Steam as Heating Agent 76
Hot Producer Gas as Heating Medium 78
Hot Coke-oven Gas as Heating Medium 79
Carbonisation by means of Flue Gasses 80
Section 6
3. Combined Apparatus 81
Hot-Run Generators fitted with Carbonising Retorts 81
Retorts Combined with Low-Temperature Producers 84
Preliminary Carbonization of Furnace Fuel 87
(p) The Influence of Retort Design Upon the Composition of Primary Tars and Gas Benzines 89
(q) The Influence of Coal Drying on the Oil Recovery 91
(r) Utilisation and Working-Up of Primary Tar 94
1. Direct Utilisation of Primary Tar  94
2. Working-Up of Primary Tar by Distillation 94
Chemical Changes on Distillation 94
Section 7
Working-up by Distillation at Ordinary Pressure 97
Distillation at Ordinary Pressure and Chemical Treatment 99
Working-up of Primary Tar by means of Superheated Steam and Chemical Treatment 100
Working-up in a High Vacuum 104
3. Separation and Utilisation of Phenols 106
The Disadvantages of Phenols and their Corrosion of Metals 106
The Utilisation of Phenols 108
Methods of Separation of Phenols hitherto in Use 108
Section 8
The Recovery of the Phenols by means of Superheated Water 110
Section 9
4. The Reduction of Phenols of Primary Coal Tar to Benzol and Toluol 117
Section 10
5. Benzine by Destructive Distillation of Primary Tar from Bituminous or Brown Coal 137
Benzine by Cracking of Primary Tar at Ordinary Pressure 140
Benzine by Cracking under Pressure 146
Section 11
Benzine by the Burton Process 150
Benzine by Cracking and Simultaneous Hydrogenation under High Pressure 151
6. The Hydrogenation of Primary Tars, Tar Oils and Phenols 158
With Catalysts 158
Without Catalysts 159
7. Summary of the Recovery of Light Motor Spirits From Primary Tars 160
8. Purification of Primary Tar Oils by Oxidation Under Pressure 164
Section 12
9. Formation of resins and Asphalt from Primary Tar by Oxidation under Pressure 166
10. Fatty Acids from Crude Paraffin Wax by Oxidation under Pressure 166
(s) Conversion of Low-Temperature Carbonisation Tar into Coke-oven Tar 166
(t) Conversion of Brown Coal Tar into Aromatic Tar 169
(u) Liquid Motor Fuels by Hydrogenation of Coal Tar, and Especially by Naphthalene 170
(v) Importance of Primary Tar as Raw Material 173
Section 13
II. Hydrogenation of Coal 174
(a) By Means of Hydriodic Acid Under Pressure According to Berthelot 174
(b) Comparative Hydrogenation of Different Coals with Hydriodic 177
(c) Hydrogenation by Means of Sodium Formate 179
Section 14
(d) Hydrogenation by Means of Carbon Monoxide and Water 187
(e) Hydrogenation with Sodium Carbonate and Hydrogen 195
(f) Destructive Distillation of Bituminous Coal at Higher Hydrogen Pressures 197
(g) Hydrogenation of Coal According to Bergius at High Hydrogen Pressure 198
Section 15
IV. Synthetic Processes 202
(a) The Action of Electric Discharges 202
(b) Catalytic Experiments at Ordinary Pressure 203
(c) Liquid Hydrocarbons from Carbon Monoxide and Hydrogen Under Pressure 206
(d) Alcohols and Formaldehyde from Carbon Monoxide and Hydrogen Under Pressure 210
(e) Methyl Alcohol and Oils by Decomposition of Formates 211
Section 16
(f) Synthol From Carbon Monoxide and Water Vapour Under Pressure 213
(g) Catalytic Experiments in the Presence of Nitrogen 219
(h) Catalytic Experiments with Carbon Dioxide and Hydrogen under Pressure 221
(i) Synthol from Water Gas Under Pressure 221
1. On the Need of a Metallic Hydrogen Carrier in the Contact Material 221
2. Influence of the Form and Length by the Contact Material 223
3. Influence of Bases and their Quantity upon the Oil Yield 224
Section 17
4. Experiments with Hydrogen Carriers other than Iron 227
5. Influence of the Composition of Water Gas 229
6. Influence of Impurities in Water Gas 232
7. Influence of Temperature, Pressure and Gas Velocity 232
8. Determination of Yields in the Circulation Apparatus 234
(k) Carbon Dioxide and Hydrogen in the Circulation Apparatus 240
(l) Carbon Dioxide and Methane in the Circulation Apparatus 241
Section 18
(m) Carbon Monoxide and Methane in the Circulation Apparatus 241
(n) Examination of Products of Reaction 246
(o) Road Tests of Synthol 248
(p) Conversion of Synthol into Synthin 248
(q) Formation of Petroleum from Water Gas 248
(r) Attempt at an Explanation of the Synthol Process 250
Section 19
(s) Industrial Applicability of the Synthol Process 255
V. Hydrocarbons from Carbides 258
(a) Carbides which Directly Yield Liquid Hydrocarbons 258
(b) Carbides Giving Hydrocarbons which can be Converted inot Liquids 261
Appendix (Editor's Notes) 263
(a) Recent Developments in Low-Temperature Carbonisation 263
Parker Plant 263
Maclaurin 266
Section 20
(b) Lessing Process for the Separation of Oils and Pitch from Tar 269
(c) Hydrogenation of Coal in the Absence of Oil 271
Bibliography 274
Index 279