4 the state of science in south africa
C H E M I S T R Y
Apart from the vast knowledge of uranium the national repository for low- and medi-
and fluorine chemistry that was developed um-level radioactive waste, situated in the
and which is still being expanded at Necsa, Northern Cape.
plasma processing technology is an impor-
tant research focus. Through high-temper-
4.8 Mintek
ature processes, many nano-oxides were
synthesised in the past, and one-step con-
version processes for UF
6
to lower uranium
fluorides or oxides were developed. Today,
plasma technology plays an important
M
intek, an autonomous statutory
body, is South Africa’s national
mineral research organisation
role in mineral beneficiation programmes
mandated to serve the country’s interest
undertaken at Necsa. In future this tech-
through research, development and tech-
nology will also play an important role in
nology transfer in the promotion of miner-
nuclear waste volume reduction in the
al technology and in the fostering of indus-
form of matrix destruction of compressible
tries in the field of minerals and products
waste.
derived from them. In particular, it special-
ises in mineral processing and extractive
Necsa, through its subsidiary NTP Radioiso-
metallurgy, with chemistry being the basis
topes (Pty) Ltd, is the world’s third largest
of many of the projects and programmes.
producer of radiochemicals, which serve
Three major programmes involving chem-
as raw materials for the formulation of
istry have respectively focused, and con-
radiopharmaceuticals for diagnostic stud-
tinue to focus, on cyanide usage in the
ies or therapeutic applications. The main
gold mining industry, on the development
radioisotope in this regard is Mo-99, with
of new industrial and commercial uses of
I-131 being another important isotope.
gold, and on flotation processes.
The chemical processes to extract and pu-
rify these fission products from irradiated
In collaboration with the gold mining
targets containing U-235 was developed
industry, the organisation, through its
in-house by Necsa scientists. Isotope pro-
scientists and engineers, has developed
duction research is complemented by the
a unique set of products and services to
development of new radiopharmaceuti-
assist with risk minimisation in the use of
cals and radiolabelled compounds, for use
cyanide. The knowledge generated during
in either clinical applications or research on
early phases of research was applied to the
the biodistribution and treatment efficien- production of online analysers, to assist
cy of non-radioactive pharmaceuticals. with compliance audits, and to discharge
monitoring services based on accredited
No significant nuclear activity is complete analysis. These services found accept-
without addressing the safe treatment and ance and are now applied throughout the
disposal of radioactive waste. The invalu- gold mining industry of Africa and further
able contribution of Necsa scientists have afield. The industry has benefited in partic-
resulted in the establishment of Vaalputs, ular from reduced reagent additions, mini-
126
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