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Comparative life-cycle analysis of synthetic detergents and biosurfactants—an overview 517

Table 23.2 List of life-cycle analysis conducted on surfactants as examples.
Name of the Type of surfactant Reference
surfactant
STPP, Zeolite, NTT Detergent builders Morse et al. (1995)
Zeolite A (detergent builder) Fawer et al. (1998)
Laundry detergents Database of different detergents Saouter and Hoof (2002)
Laundry detergents Both petrochemical-based and Schowanek et al. (2018)
oil-based detergents
Methyl ester Palm oil based Zolkarnain et al. (2016)
sulfonates
Alkylpolyglucoside Plant oil-based biosurfactant Guilbot et al. (2013)

The use of gas to liquid-based methods for linear alkylbenzene synthesis compared
to conventional methods is found to emit considerably fewer quantities of green-
house gases thereby reducing its effect on global warming (Forman et al., 2014).

23.5 Industrial production and life-cycle analysis
of biosurfactants

Biosurfactants are regarded as the green surfactants owing to their eco-friendliness,
biodegradability, and least toxicity compared to synthetic surfactants.
Biosurfactants can be divided as two, namely, the ones produced using the plant-
derived fatty acid and microbially derived biosurfactants. Biosurfactant synthesis
involves various steps as shown in Fig. 23.4.
A study on the synthesis of palm oil based methyl ester sulfonates (MES) indi-
cated that most impact categories include fossil fuel, respiratory organic com-
pounds, and climate change and they were found to be comparatively less when
compared to the impact caused by conventional petroleum-based production techni-
ques (Zolkarnain et al., 2016). In a similar context, the comparative LCA of LAS
(synthetic detergent) and MES revealed that the latter was found to be more eco-
friendly in terms of significant risk factors associated with its production
(Thannimalay and Yusoff, 2014).
A relative analysis of different biosurfactants, such as rhamnolipids and sophoro-
lipids, indicates that the major contributors to environmental impact include air
emissions, electricity, and thermal requirements (Kopsahelis et al., 2018). The pro-
duction of acetylated sophorolipids is found to be much more efficient than sophor-
olipids in terms of the toxicity associated with it (Baccile et al., 2016). The LCA on
the green synthesis of oil-based alkylpolyglucoside indicated that phases of its for-
mulation and terminal use played a critical role in its environmental impact contri-
bution of 15% and 51%, respectively (Guilbot et al., 2013). The study also laid
forward the environmental benefits of replacing glass bottles instead of plastic.