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Green Chemistry & Engineering key to
transition India’s chemical industry to a sustainable growth path
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The
modern chemical industry has made significant societal impact through
innovations that have led to the wide availability of products as diverse as
drugs, pesticides, fertilisers, manmade fibres, plastics & rubbers, soaps
& detergents etc. But the industry has also put out stuff now recognised
to be toxic or hazardous to human/animal health or to the environment. The
latter list is growing as the underlying science gets better, and includes
thalidomide (a drug), DDT (an agrochemical), chlorofluorocarbons (ozone
depleting substances), endocrine disruptors, persistent organic pollutants
etc. Indeed, several chemicals used in large volumes have come under the
cloud even as regulators are taking diverse approaches to regulate their use.
Both
as a consequence of the dangers posed by some products and the processes to
make chemicals, the societal image of the chemical industry remains poor.
What was once seen as an innovative industry churning out life-changing
products is now viewed in many parts of the world as a problem, but one that
cannot be wished away! This has several consequences – not just for industry,
but for society at large – and is most intensely reflected in the way
governments monitor and regulate the industry. Despite attempts to put in
self-regulating mechanisms – several of which have positive impacts – the
chemical industry continues to be in the crosshairs of regulators, NGOs and
civil society.
Environmental impacts
The
environmental impacts of the chemical industry comes from its products and
the processes employed to make them. Several processes – some would say most
– generate waste in one form or the other – be it to air, water or land. The
quantum of wastes generated varies, depending on the kind of chemicals made,
but in areas as pharmaceuticals or agrochemicals this could be even a few
thousand times the quantity of the desired product. This ratio – famously
called the e-factor (the ‘e’ standing for environment) – is now widely
recognised as a simplistic barometer of how ‘green’ or environment-friendly a
process is.
The
chemical industry’s approach to tackling the problem of wastes has changed
significantly, especially in the last few decades. From ignoring the problem,
the industry has evolved to integrate waste treatment strategies into overall
manufacturing schemes. Most reputed chemical companies today monitor their
release of wastes, and ensure compliance as per the laws of the land or, at
times, mandates of customers. They also have clearly defined, and often well
publicised, targets for improvement and when all else fails contain the
damage wastes may cause by keeping them secure (as in a well-built landfill).
While
this still continues to be the model for much of the industry, it does have
obvious limitations. Society is clearly expecting more from industry and is
less tolerant of its lapses. At the receiving end, ecological systems are
becoming overburdened; landfills, for example, are filling out and
permissions to build more are hard to come by.
Old chemistries and technologies
Part
of the problem stems from the fact that the chemical industry still practices
very old chemistry. Indeed, a random selection of 100 chemistries in a review
of named reactions revealed that 54% were developed before World War I, 74%
before World War II, and 91% before 1975. Just 9% were developed in the
1980s. Chemical technologies too have not changed very significantly – batch
reactors can be traced back to the Bronze Age, as can rudimentary means of
carrying out crystallisation.
What
have however changed over the decades are the costs of operating plants using
these chemistries. While just a few decades ago process costs were largely
operational, it has ballooned to now include regulatory compliance, waste
treatment/control/mitigation and, at least in some countries, liability. In
sync with the number of regulations that now govern the industry – about 150
– the expenditure on waste treatment has swollen to a few hundred billion
dollars. In an industry valued at about $4 trillion today, this is not an unacceptable
burden, but still one to cause concern about sustainability. This number also
does not include the costs that would need to be incurred to clean the
historical baggage of wastes accumulated over decades. To give just one
example – though a dated one – DuPont’s environmental budget in 1996 matched
its research budget, at $1-bn each, on sales of $18-bn.
Preventing waste, rather than cleaning it up
To
the credit of the chemical industry it has recognised that the old way of
creating and then fixing the problem will simply not do. Pollution prevention
is now the mantra in all sectors of the industry and in all regions. The idea
here is simple: prevent waste from being generated in the first place through
an astute orchestration of ‘green’ chemistry and engineering (GCE), process
control, in-process recycling and simple housekeeping changes.
GCE
involves designing chemical products and processes that reduce or eliminate
the use and/or generation of hazardous substances and represents a
fundamental shift in the way science views chemical design and synthesis. GCE
approaches also focus on the minimisation, if not elimination, of the hazard
associated with a chemical. This is a departure from earlier approaches to
safety management that focussed on the minimisation of exposure to minimise
risk (remember: risk = hazard X exposure). Reducing intrinsic hazard, for
example by choosing a less toxic raw material, is a more fail-proof approach
to risk management than simply focussing on exposure through, say, process
control. Of course, this may not be possible in all cases and exposure
reduction through the right process choices and the deployment of appropriate
technologies continues to be an important strategy to enable a safer chemical
industry.
The
discipline of GCE has come a long way since John Warner and Paul Anastas
enunciated its 12 Principles. It goes beyond pollution prevention at the
molecular level and encompasses designing chemicals that are benign to the
environment, both by itself and through their degradation products after its
useful life. Better understanding of structure-activity relationships and
advances in computational capabilities now make it possible to predict
physicochemical properties (including toxicity) and permit the design of molecules
with the desired functionality. Nowhere else are these approaches more widely
used than in the pharmaceuticals and agrochemicals industries.
From
a process angle, GCE approaches emphasise the use of inherently safer
chemistry – an aspect that received great attention after the terrible Bhopal
accident that involved an accidental release of an agrochemical intermediate,
methyl isocyanate. Non-phosgene routes for making isocyanates or
bio-catalytic routes for fine chemicals that operate under more benign conditions
of temperature and pressure, are but two examples of such approaches.
A
significant quantum of work has gone into the replacement of hazardous
solvents by safer ones, particularly by the leading pharmaceutical companies
of the world – individually and collectively. Much of this body of work is
now available in the public domain and companies here in India can surely
benefit.
Key to sustainable growth
Adoption
of GCE principles and integrating them into innovation and manufacturing is
key to sustainable growth of the Indian chemical industry. The industry, in
general, and the highly waste-generating fine chemical industry, in
particular, is targeting double-digit growth for several decades. But this
cannot happen in the business-as-usual manner that underpinned growth so far.
The industry clearly needs to move towards a more environmentally responsible
path of development – one that uses raw materials judiciously and with the
utmost efficiency to make products that are neither harmful to those producing
or using it, and to the environment. It needs to have the smallest ecological
footprint possible.
The
reasons cited for inability to change to this model of growth – lack of
capital, inability to access affordable technology, problems with regulators (especially
in the pharmaceuticals industry) – are excuses that can be circumvented
through a clear commitment and leadership from senior management and a
mind-set change down the multiple management layers. The difficulty often
lies, not in the new ideas, but in escaping old ones. But change is no longer
an option, but crucial to the survival of the industry, and its reputation in
society.
Learning from others
There
are many examples of successes in GCE – especially from the US and Western
Europe – and much to be learnt from them. Last week, this newspaper had
covered the ‘2017 Green Chemistry Challenge Awards’ that honoured landmark
GCE developments. This week, we feature salient features of an upcoming event
– the 5th Industrial Green Chemistry World (IGCW) convention
and expo to be held in Mumbai from October 5-6 – that provides an opportunity
to learn from the pioneers of the GCE world.
GCE
is more than just hazard, risk and pollution reduction. It is a philosophy
that can enable the chemical industry transition to a more sustainable path
of growth. Chemists and chemical engineers are uniquely trained to enable
society to do this. Looking within will be a good place to start!
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- Ravi
Raghavan
CHWKLY 11JUL17
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