Page 173 - CW E-Magazine (14-1-2025)

Special Report

to almost 8% of the world’s electricity.
It seems that there are 329,000 turbines
globally. Whereas 85% of the material
in a turbine, including steel, copper wire
and gearing, are recyclable, blades pose
problems which as of now after cutting
are going for landfill. There is an esti-
mate that by 2050, 43-million tonnes
of blades will be discarded. As of now
around 12,000 blades are decommis-
sioned in Europe and US.

Several attempts are being made for developed to produce spherical AS HCN to make cyanohydrin was traced to
recycling of blades, which use epoxy particles through a single heating step certain brands of ACN, used during the
resins. Mechanical recycling separates without the use of organic solvents. This analysis. Different analytical methods,
blades into their fiber, resin, and metal product has high flowability, excellent including ion chromatography, were
components. powder properties, good sphericity and adopted. (Org. Proc. Res. Dev. 2024;
Attempts have been made to destroy high flowability. The dissolution rate DOI: 10.1021/acs.oprd.4c00336).
epoxy resin at high temperatures. A team reduces by 20% compared to that of
in China (Zhang’s team) cuts blades into cubic particles and caking decreases by Continuous flow synthesis and
pieces and puts it in a benign solvent; 30%. (Ind. Eng. Chem. Res. 2024; DOI: crystallisation of Modafinil (M)
addition of a low-cost acid splits the 10.1021/acs.iecr.4c02589).
resins into oligomers that can be reused D.V. Silva-Brenes et al have come out
to make polymers. Deoxygenation of solvents with a novel approach for integrated
manufacturing of M, which is an anti-
In yet another method, the resin is ex- For many processes the dissolved O in narcoleptic drug. This required optimi-
2
posed to a mixture of fine NaOH powder solvents is harmful, and different methods sation of the reported flow synthesis of
and toluene solvent at 190°C and this are available to tackle this problem. M, for prolonged operation and consis-
breaks apart the resin and thus bisphenol Now D. Park et al come out with an tent crude quality. The reactor effluents
A is recovered. enhanced deoxygenation method with were taken for downstream purification
an improved inert gas bubbling method using two single-stage mixed suspension
There is a reference to Ru-based catalyst with a ventilation pathway. The known mixed product removal crystallisers. The
and toluene and isopropanol as solvent method of Freeze-Pump-Thaw (FPT) is first stage was an antisolvent cooling
to cleave C-O bonds in epoxies. There effective but time consuming. Examples crystallisation. The second stage was
are attempts to make degradable epoxies. of acetonitrile and toluene are given. used to get the required polymorphic
Epoxy anhydride chemistry is referred. (ACS Omega, 2024; DOI: 10.1021/ form. (Reaction Chem. Eng., 2024; DOI:
(Chem. Eng. News. 2024, 7 Oct, 15-19). acsomega.4c05786). 10.1039/D4RE00273C).

Preparation of (NH ) SO (AS) Analytical artifact due to resi- Polyethylene (PE) recycling via
4 2
4
spherical particles with func- dual HCN in acetonitrile (ACN): water activation by ball milling
tions of sustained release and Identification and control
anticaking by an organic sol- strategies L. Li et al have come out with an inte-
vent-free process [When ACN comes as a byproduct in resting and potentially useable way of
manufacturing acrylonitrile by ammoxi- recycling of PE, which is an important
AS continues to be an important fertiliser, dation of propylene, HCN is also present problem (some aspects have been covered
particularly for sulphur-deficient soils. J. and it can become an impurity at, say, in this column). This method avoids high
Li et al have investigated the effects of ppm level in ACN.] temperature and noble metals. An unprece-
the abrasives and dissolution processes dented mechanochemical reaction of
on the morphology of AS crystals. By a V.K. Kadambar et al have worked on PE with water is reported, which gives
study of the cooling rate, stirring rate, an API where at ppm level cyanohydrin products as valuable feedstocks. Here the
and heating methods, a technique was derivative was detected. The source of reaction is driven solely by ball milling,

Chemical Weekly January 14, 2025 173

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