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 Reduced ...... 211 10.3 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 Not Reduced . . . . 212

ix TABLES

2.1 Economic Summary of Butylenes Separation Processes (Starting with a Steam Cracked Mixed B-B Stream) ..... 5 3.1 Availability of Raw Butylenes in the United States .... 11 3.2 Availability of Raw Butylenes in Western Europe ..... 12 3.3 Availability of Raw Butylenes in Japan ...... 12 3.4 Producers of High Purity Isobutylene ...... 14 3.5 Producers of High Purity Butene-1 ...... 15 3.6 Raffinate-2 Streams Resulting from Isobutylene Removal viaMTBE ...... 16 3.7 U.S. Consumption of High Purity Isobutylene ...... 17 3.8 Plant Capacities for Making Butyl Rubber ...... 19 3.9 Consumption of Butyl Rubber ...... 19 3.10 Polyisobutylene Plants ...... 21 a 3.11 Consumption of Low Density Polyethylene by End Use .... 23 3.12 Status of Various LLDPE Processes that use Butene-1 as Comonomer ...... 24 3.13 Consumption of High Purity Butene-1 as Polyethylene Comonomer ...... 25 4.1 Pure Isobutylene Through Cracking of Tertiary-Butyl Ethers ...... 37 4.2 Pure Isobutylene Through Dehydrating of Tertiary-Butanol Patent Summary ...... 48 4.3 Pure Isobutylene Through Cracking of 0 Tertiary-Butyl Esters PatentSummary ...... 54 4.4 CFR Extraction Process for Isobutylene Summaries .ofSelected Patents ...... 68 4.5 Butylene Separations using Molecular Sieves PatentSummary ...... 72 4.6 Typical Butadiene Plant Rsffinate ...... 79

Xi TABLES

4.7 Partial Hydrogenation Processes for Butylenes -Patent Summary...... 81 4.8 Butene-1 Specifications and Analyses ...... i . . . . 84 4.9 Butyl Rubber Grade Isobutylene ...... 85 5.1 High Purity Isobutylene by Acid Extraction (CF'R Technology) Major Equipment ...... 90

5.2 High Purity Isobutylene by Acid Extraction (CFR Technology) Utilities Sum&y ...... 92

5.3 -High Purity Isobutylene by Acid Extraction (CFR.Technology) StreamFlows...... 93 5.4 High Purity Isobutylene by Acid Extraction (CFR Technology) Plant Design Conditions ...... 94 5.5 High Purity Isobutylene by Acid Extraction (ICFR Technology) Total Capital Investment . . . , ...... 99

5.6 High Purity Isobutylene by Acid Extraction (CFR Technology) Capital Investment by Section , ...... 100 5.7 High Purity -1sobutylene by Acid Extraction ($Z'R Technology) Production Costs . .-...... 101 5.8 Eigh Purity Isobutylene by Acid Extraction (CFR Technology) Direct Operating Costs by Section ...... 103 6.1 High Purity Butene-1 Through Use of Molecular Sieves (UOP Tachnology) Major Equipment ...... 112 6.2 .High Purity Butene-1 Through Use of Molecular Sieves (UGP Technology) Utilities Sumary . . :...... '...... 114 6 .J High Purity Butene-1 Through Use of Molecular Sieves (UOP Technology) StreamFlows...... 115

Xii TABLES

6.4 High Purity Butene-1 Through Use of Molecular Sieves (UOP Technology) Plant Design Conditions ...... 116 6.5 High Purity Butene-1 Through Use of Molecular Sieves (UOP Technology) Total Capital Investment ...... 121 6.6 High Purity Butene-1 Through Use of Molecular Sieves (UOP Technology) Production Costs ...... 123 6.7 High Purity Butene-1 Through Use of Molecular Sieves (UOP Technology) . . . Direct Operating Costs by Section l l l l l l l l l . 125 7.1 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case A MajorEquipment ...... 134 7.2 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case A Utilities Summary ...... 136 7.3 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case A StreamFlows ...... 137 7.4 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology) Plant Design Conditions ...... 138 7.5 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case A Total Capital Investment ...... 144 7.6 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case A Capital Investment by Section ...... 145

Xiii 7.7 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case B Total Capital Investment ...... 146 7.8 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case B Capital Investment by Section ...... 147 7.9 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case A Production Costs ...... 148 7.10 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology), Case B Production Costs ...... 150 7.11 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology) Economics of Superfractionation To Improve Quality of the Isobutylene Product ...... 151 7.12 High Purity Isobutylene and Butene-1 Through Use of Molecular Sieves (UCC Technology) Derivation of Product Values ...... ; ...... 152 8.1 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol Major Equipment ...... 158 8.2 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol Utilities Summary ...... 159 8.3 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol StreamFlows...... k i . 160 8.4 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol Plant Design Conditions ...... 161

xiv TABLES

IlighPurity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol Total Capital Investment . . . . . h ...... 165 8.6 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol 0 Capital Investment by Section ...... 166 8.7 High Purity Isobutylene by Catalytic Dehydration of Tertiary Butyl Alcohol Production Costs ...... 167 8.8 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol Direct Operation Costs by Section ...... 169 8.9 High Purity Isobutylene by Catalytic Dehydration of Tertiary-Butyl Alcohol Production Cost Breakdown Between the TBA Synthesis Plant and the TBA Dehydration Plant ...... 171 9.1 High Purity Isobutylene by Catalytic Cracking of Methyl Tertiary-Butyl Ether Major Equipment (Case A) ...... 176 9.2 Eigh Purity Isobutylene by Catalytic Cracking of Methyl Tertiary-Butyl Ether Utilities Summary (Case A) ...... ‘...... 178 9.3 High Purity Isobutylene by Catalytic Cracking of MTBE (Case A) StreamFlows...... , ...... 179 9.4 High Purity Isobutylene by Catalytic Cracking of Methyl Tertiary-Butyl Ether Plant Design Conditions ...... 180 9.5 High Purity Isobutylene by Catalytic Cracking of Methyl Tertiary-Butyl Ether Total Capital Investment (Case A) ...... 184 9.6 Digh Purity Isobutylene by Catalytic Cracking of Methyl Tertiary-Butyl Ether 0 Capital Investment by Section (Case A) ...... 185 9.7 High Purity Isobutylene by Catalytic Cracking of MTBE Case B Total Capital Investment ...... 186

xv a

TABLES

0 9.8 High Purity Isobutylene by Catalytic Cracking of MTBE (Case B) Capital Investment by Section ...... 187 9.9 High Purity Isobutylene by Catalytic Cracking of MTBE Production Costs (Case A) ...... 188 9.10 High Purity Isobutylene by Catalytic Cracking of MTBE -(CaseB) Production Costs ...... , ...... 190 9.11 High Purity Isobutylene by Catalytic Cracking of,MTBE Economics of Adding Purification Section to Improve the Quality of the Isobutylene Product ...... 191 10.1 High Purity Butene-1 by Distillation of MTBE Plant Raffinate Major Equipment ...... c , ...... 196

10.2 High Purity Butene-1 by Distillation 0 of MTBE Plant Raffinate Utilities Summary ...... 198 10.3 High Purity Butene-1 by ,Distillation of MTBE Plant Raffinate StreamFlows ...... 199 10.4 Uigh Purity Butene-1 by Distillation of MTBE Plant Raffinate Plant Design Conditions ...... 230 10.5 Kigh Purity Butene-1 by Distillation of MTBE Plant Raffinate Total Capital Investment ...... ; . . . 205 10.6 High Purity Butene-1 by Distillation 0 of MTBE Plant Raffinate Capital Investment by Section ...... 206 10.7 High Purity.Butene-1 by Distillation of MTBE Plant Raffinate Production Costs ...... 207 0

xvi TABLES

10.8 High Purity Butene-1 by Distillation of MTBE Plant Raffinate Production Cost Breakdown Between the MTBE Plant and the Butene-1 Recovery Plant ...... 209 10.9 High Purity Butene-1 by Distillation of MTBE Plant Raffinate The Effect of Changing Component Values on the Calculated Product Value for High Purity Butene-1 . . . . . 210

xvii