Page 21 - CW E-Magazine (Oct-Nov-2023)

Flow Chemistry

These large scale efforts are back- them continuous, maximize energy helped create some visibility for the
up by a large number of start-up firms integration, try using integrated unit techniques and methods, which subse-
and government-led efforts including operations, treat waste at the source quently grew significantly through li-
Continuous Pharma, Snapdragon Chem- of generation); censing of various processes, designs,
istry, NJ Biopharmaceuticals, Lonza * Cross the barriers of scale, time, op- etc., and through filing of large number
Pharma & Biotech, Ampac Fine Chemi- erating conditions; of patents. Subsequently, IIT-Bombay
cals, TCG GreenChem, (Curia) AMRI * Eliminate or reduce the need of and CSIR-IICT also created some early
Global, Adesis, Phlow Corporation, Ad- downstream processing (select the stage facilities.
vanced Tech. & Manufacturing Institute, reactors that are dictated by the re-
J-Star Research, Continuity Pharma, action, reaction rates of the desired As of now, there are over 15 CROs
RAPID Institute (all from USA). A simi- and undesired reactions); and start-ups that facilitate support
lar number of efforts are ongoing in oth- * Develop sustainable new chemistry of flow chemistry needs in the coun-
er countries (UK, Germany, The Neth- (avoid using solvents, avoid using try (viz., Amar Equipments Pvt. Ltd.,
erlands, Spain, France, Canada, Russia, toxic chemicals, avoid generating Sravathi Eng. Pvt. Ltd., TechnoForce
Israel, Japan, South Korea, China, etc.). toxic waste). Pvt. Ltd., MakSpeed Pvt. Ltd., Corning
The big pharma companies – Pfizer, Ltd., Continuous Flow Asymchem Pvt.
Merck, Amgen, Corteva, Dupont-Dow, National status Ltd., Sreeni Lab, ChemDist Pvt. Ltd.,
Sanofi, Inycte, Mirati Therapeutics, Unlike other western countries, in Prayog Life Sciences, GMM Pfaudler
BMS, Lonza, Novartis, GSK, Takeda this area we have not been very late. In Ltd., etc.). Many of the large chemi-
Pharma, Eli Lily, Abbot, etc. – also have middle of the 1 decade of this century, cal manufacturers have their own flow
st
well-established programmes on contin- CSIR-National Chemical Laboratory facilities (viz., Syngene Flow Lab, US
uous flow synthesis and manufacturing, (CSIR-NCL) started exploring CFS for Pharmacopia Centre for Continuous
at lab, pilot scale and, in some cases, at complex reactions. The purpose was to Flow Synthesis, DRL’s Flow Synthesis
commercial scales. showcase the usefulness of such tech- Laboratory, Aarti Industries, Deepak
nologies that were extremely expensive Nitrite, PI Industries, IPCA Labora-
What is the urgency? at that time to the Indian chemical in- tories, CIPLA Ltd., Sun Pharma Ltd.,
In the Indian fine and specialty chem- dustry and in parallel build capability to Biocon Ltd., Aurobindo Ltd., Aether
icals industry, in several plants the pro- absorb such technologies, both in terms Industries Ltd., Anupam Rasayan Ltd.,
cesses are quite old, follow conventional of fabrication and supply of such reac- Godrej Ltd. etc.). As per our estimates,
synthesis routs, use very large amounts tors in India and using them for various over 250 Indian chemical industries
of solvents (which are often recovered reactions at different scales. The Indus- are practicing flow synthesis at various
and recycled back as per the efficiency try Consortium on Microreactors with scales in India, and this number is ex-
of the recovery systems), which leads to over 15 industry members at that time pected to jump to 500 in next two years.
significant downstream processing and
thus reduces the profit margins signifi-
cantly. In many cases the plants produce
large quantities of waste (effluent, VOCs
and solids) and the operations are based
on toxic materials that force one to have
huge inventories. These features often
arise due to batch or semi-batch mode of
operations as well.

However, a few solutions that are
now proven must be explored for every
single possible and potential synthesis
implemented. Some of these include:
* Revisit the chemistry (make it green,
use new synthesis techniques, use
heterogeneous catalysts);
* Re-engineer the processes (make Figure 1: Opportunities in the space of continuous manufacturing

Chemical Weekly October / November 2023 17