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Technology in Australia 1788-1988Australian Academy of Technological Sciences and Engineering
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Table of Contents

Chapter 9

I Introduction

II The Australian Chemical Industry

III Pharmaceuticals

IV Chemists In Other Industries

V The Dawn Of Modern Chemical Industry - High Pressure Synthesis

VI The Growth Of Synthetic Chemicals - Concentration, Rationalisation And International Links

VII Australian Industrial Chemical Research Laboratories

VIII The Plastics Industry
i Plastics processing
ii Phenol - basis of the first plastic
iii Plastics - the first generation
iv Plastics - the second generation - from petrochemicals
v Styrene monomer - the West Footscray petrochemical complex
vi The Botany petrochemical complex
vii The petrochemical complex at Altona
viii CSR - from sugar alcohol to petrochemical OXO alcohol

IX The Paint Industry

X Acknowledgements

References

Index
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Oxychlorination -a new vinyl chloride process:
international success and an Australian plant (continued)


Two other inventions relating to the PVC process were made in the 1970s; both were crucial to the plant's operation. One related to the prevention of build-up of PVC polymer on the walls of the polymerisation reactor. The layers of PVC formed on the walls prevented heat transfer and hence control of the reaction. Manual cleaning of the reactors required physical effort under difficult conditions and caused loss of productivity. The problem had plagued the industry -worldwide -for many years. Chemical treatment of the reactor walls with build-up suppressants -after many trials -overcame the problem.

The other task was even more critical. In the 1970s hitherto unknown toxicity of vinyl chloride at extremely low concentrations was discovered and the last traces of this gas had to be removed from the finished PVC polymer particles, well below the limits set by the health authorities. Since the gas was dissolved in the polymer and removal was diffusion-controlled, elevated temperatures were required, yet PVC tends to degrade at high temperatures. The problem was solved by an elegant continuous process of high speed stripping gas from the solids suspended in water cascading down a counter-currently operating column, which reduced the gas content to fractions of parts per million without thermal degradation of the polymer. A full scale plant unit was installed (Fig. 30) and the process was subsequently adopted by overseas companies. The sudden discovery of vinyl chloride toxicity was a world-wide problem; everywhere industry had to face the task of controlling emissions to fractions of parts per million. Throughout this world-wide safety campaign of improved process control the key analytical tool was the ICI/McWilliam flame ionisation detector; by then automation of the instrument with computer control had progressed to the stage that well over one thousand analyses were done each day on the plant to ensure absolutely safe working conditions.

Figure 30

30 Continuous vinyl chloride stripping form PVC. Full scale plant at Botany.

Ethylene oxide and derivatives

While the oxychlorination process was primarily an achievement of Australian research and development, and polythene in essence was technology transfer, ethylene oxide and its derivatives were a mixture of the two. In the UK, ICI and in Australia, Timbrol had long made ethylene-glycol, an important chemical intermediate best known to the wider public for only one of its uses, as a car radiator fluid. The ICI process based on epichlorhydrin did not suit ICI Australia's constellation; chlorine prices were rising and the process appeared obsolescent. Research and development teams, therefore, evaluated alternative processes and, eventually, secured an early licence from an emergent American company, R. Landau's Scientific Design. This was a matter of prudent buying, as the process was still at an early development stage, when entry terms were favourable but entailed an element of risk, and hence confidence in one's own evaluation.


Organisations in Australian Science at Work - Botany Petrochemical Complex; I.C.I. Australia Ltd; I.C.I. Australia Ltd. Central Research Laboratories; Timbrol Ltd

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© 1988 Print Edition pages 705 - 706, Online Edition 2000
Published by Australian Science and Technology Heritage Centre, using the Web Academic Resource Publisher
http://www.austehc.unimelb.edu.au/tia/672.html