PROCESS ECONOMICS PROGRAM SRI INTERNATIONAL Menlo Park, California 94025 Abstract Process Economics Program Report No. 71A BUTTLENES (October 1982) Demand is fast increasing for lsobutylene, especially that used in manufacturing methyl tertiary-butyl ether, and for high purity butene-1 to use as a copolymer in linear low density polyethylene. Because of their wide availability, mixed butane-butylene streams from oleflns plants and petroleum refineries are being increasingly fed to plants to separate butylenes for use in chemicals. This first supplement to Report No. 71 updates demand projections, production capacities, and separation techniques for high purity butene-1 and lsobutylene. The processes that are now available for separating and purifying both butene-1 and lsobutylene from mixed butyl- ene streams are evaluated and compared. Other procedures for obtaining butylenes, such as dehydrogenatlon, lsomerleatlon, and disproportion&ion, are not updated in this report. PEP’81 JLC Report No. 71A - BUTYLENES SUPPLEMENT A by JOHN L. CHADWICK I I October 1982 f-F0 0 A private report by the m PROCESS ECONOMICS PROGRAM 0 Menlo Park, California 94025 0 For detailed marketing data and information, the reader is referred to one of the SRI programs specializing in marketing research. The CHEMICALECONOMICS HANDBOOK Program covers most major chemicals and chemical products produced in the United States and the WORLDPETROCHEMICALS Program covers major hkdrocarbons and their derivatives on a worldwide basis. In addition, the SRI DIRECTORYOF CHEMICALPRODUCERS services provide detailed lists of chemical producers by company, prod- uct, and plant for the United States and Western Europe. ii CONTENTS 1 INTRODUCTION . 1 2 SUMMARY . 3 Butylenes Availability and Uses ............... 3 Butene-l.......................... 3 I . Isobutylene ........................ 4 Separation Process Comparisons ................ 4 3 INDUSTRY STATUS ....................... 9 Sources of Raw Butylenes ................... 9 Sources of High Purity Isobutylene .............. 10 Sources of High Purity Butene-1 ............... 13 Consumption of High Purity Isobutylene ............ 13 Butyl Rubber ........................ 18 Polyisobutylene ...................... 20 Consumption of High Purity Butene-1 ............. 20 Butene-1 Comonomer in Polyethylene ............. 20 e Polybutene-1 ........................ 22 4 REVIEW OF TECHNICAL DEVELOPMENTS . 27 Effect of Gasoline Lead Levels on Butylenes Separation .... 27 Effect of Polyethylene Technology on Processing for Butene-1 ................... 28 Butylenes Separation Processes ................ 29 Separations Through Chemical Conversions .......... 31 Pure Isobutylene Through Cracking Tertiary-Butyl Ethers .................. 31 Pure Isobutylene Through Dehydration of Tertiary.-Butanol ................... 44 Arco Technology ..................... 47 0 Soviet Technology ........ .,........... 50 Liquid Phase Process ................... 52 Mineral Acid Catalyst .................. 53 Acid Ion Exchange Catalyst ................ 56 Further Discussion .................... 59 Separations Through Acid Extraction ............ 59 0 The Exxon Sulfuric Acid Extraction Process ........ 61 The BASF Sulfuric Acid Absorption Process .... ; ... 63 The CFR Sulfuric Acid Extraction Process ......... 65 The Nippon Hydrochloric Acid Extraction Process ..... 69 Physical Separations Using Molecular Sieves ........ 71 iii CONTENTS 4 REVIEW OF TECHNICAL DEVELOPMENTS (continued) Union Carbide's OlefinSiv Process ............ 74 UOP's Sorbutene Process ................. 76 Feed Preparation and Purification of Products ........ 77 Partial Hydrogenation of Feed Streams ........... 77 Butene-1 Purification ................... 83 Isobutylene Purification ................. 85 5 HIGH PURITY ISOBUTYLENE BY ACID EXTRACTION (CFR TECHNOLOGY) ...................... 87 Process Description ..................... 87 Process Discussion ..................... 95 Acid Regeneration ..................... 95 Waste Effluent ...................... 96 Metallurgy ........................ 96 Cost.Estimates ....................... 97 Capital Costs ....................... 97 Production Cost and Product Value ............. 97 6 HIGH PURITY BUTENE-l THROUGH USE OF MOLECULAR SIEVES (UOP TECHNOLOGY). T ..................... 107 Process Description ..................... 108 Process Discussion ..................... 117 Feed Preparation Section ................. 117 Adsorption Section .................... 117 Cost Estimates ....................... 118 Capital Costs ....................... 118 Production Cost and Product Value ............. 119 7 HIGH PURITY ISOBUTYLENE AND BUTENE-l THROUGH USE OF MOLECULAR SIEVES (UCC TECHNOLOGY) ...... 129 Process Description ..................... 129 Process Discussion ...................... 140 Feed Preparation Section ................. 140 Adsorption Section ................ ; ... 140 Cost Estimates ....................... 141 Capital Costs ....................... 141 Production Cost and Product Value ............. 142 CONTENTS 8 HIGH PURITY ISOBUTYLENE BY CATALYTIC DEHYDRATION OF TERTIARY-BUTYL ALCOHOL .................... 155 Process Description ..................... 155 Process Discussion ..................... 162 Cost Estimates ........................ 162 l Capital Costs ....................... 162 Production Costs and Product Value ............. 163 9 HIGH PURITY ISOBUTYLENE BY CATALYTIC CRACKING OF METHYL TERTIARY-BUTYL ETHER ................. 173 Process Description ..................... 173 Process Discussion ...................... 181 Cost Estimates ........................ 181 Capital Costs ....................... 182 Production Costs and Product Value ............. 183 10 HIGH PURITY BUTENE-l BY DISTILLATION OF l MTBE PLANT RAFFINATE ..................... 193 Process Description ..................... 194 Process Discussion ...................... 201 MTBE Preparation Section .................. 201 Raffinate Partial Hydrogenation Section .......... 201 Distillation Section .................... 201 Cost Estimates ........................ 202 Capital Costs ....................... 202 Production Cost and Product Value ............. 202 APPENDIX A TYPICAL MIXED BUTANE-BUTYLENE STREAMS ....... 213 CITED REFERENCES .......................... 215 PATENT REFERENCES BY COMPANY .................... 221 ILLUSTRATIONS l 4.1 Separation Processes for Mixed Butylene Streams . 30 4.2 Recovery of High Purity Isobutylene by Conversion to MTBE, Etherification Section , . 34 4.3 Isobutylene by Etherification with C3 and C4 Alcohols . 40 4.4 Isobutylene by Etherification in a Catalytic Distillation Column . 43 4.5 Isobutylene by Vapor Phase Dehydration of Tertiary-Butyl Alcohol . 46 4.6 Isobutylene by Tertiary-Butyl Alcohol Route, Soviet Technology . 51 4.7 Isobutylene by Esterification with Acetic Acid in the Presence of a Mineral Acid Catalyst . 55 4.8 Isobutylene by Esterification with Acetic Acid in the Presence of an Acid Ion Exchange Catalyst . 58 4.9 Isobutylene by Extraction with Sulfuric Acid, Exxon Technology . 62 4.10 Isobutylene by Absorption with Sulfuric Acid, BASF Technology . 64 4.11 Isobutylene by Extraction with Sulfuric Acid, CFR Technology . 66 4.12 Isobutylene by Extraction with Hydrochloric Acid, Nippon Technology . 70 4.13 Butylene Separation by Olefinsiv Process . 75 4.14 Butylene Separation by Sorbutene Process . 78 5.1 High Purity Isobutylene by Acid Extraction (CFR Technology) FlowSheet . 5.2 High Purity Isobutylene by Acid Extraction (CFR Technology) Effect of Isobutylene Feed Value and Plant Capacity on Net Product Value . 104 5.3 High Purity Isobutylene by Acid Extraction (CFR Technology) Effect of Operating Level and Plant Capacity on Net Product Value . 105 Vii ILLUSTRATIONS 6.1 High Purity Butene-1 Through use of Molecular Sieves (UOP Technology) ~10~ Sheet.......................... 227 6.2 High Purity Butene-1 Through use of Molecular Sieves (UOP Technology) Feedstock Dryer Regeneration Unit PAC-101 . 110 6.3 High Purity Butene-1 Through use of Molecular Sieves (UOP Technology) Effect of Butene-1 Feed Value and Plant Capacity on Net Product Value . 126 6.4 High Purity Butene-1 Through use of Molecular Sieves (UOP Technology) Effect of Operating Level and Plant Capacity on Net Product Value . 127 7.1 High Purity Isobutylene and Butene-1 Through use of Molecular Sieves (Union Carbide Technology) Flow Sheet . 229 7.2 High Purity Isobutylene and Butene-1 Through use of Molecular Sieves (UCC Technology) Molecular Sieve Decarbonization Unit (PAC-201) . 132 7.3 High Purity Isobutylene and Butene-1 Through use of Molecular Sieves (UCC Technology) Effect of Operating Level and Plant Capacity on the Net Average Product Value . 153 8.1 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol FlowSheet.......................... 233 8.2 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol Effect of Operating Level and Plant Capacity on Product Value . 170 9.1 High Purity Isobutylene by Catalytic Cracking of Methyl Tertiary-Butyl Ether Flowsheet.......................... 235 Viii ILLUSTRATIONS 9.2 High Purity Isobutylene by Catalytic Cracking of Methyl Tertiary-Butyl Ether Effect of Operating Level and Plant Capacity on Product Value . 192 10.1 High Purity Butene-1 by Distillation of MTBE Plant Raffinate FlowSheet . 237 10.2 High Purity Butene-1 by Distillation of MTBE Plant Raffinate Effect of Operating Level and Plant Capacity on Product Value of Butene-1 when Operating Level of MTBE Plant is