Page 564 - Refining Biomass Residues for Sustainable Energy and Bioproducts

514 Refining Biomass Residues for Sustainable Energy and Bioproducts

The essentiality of LCA to identify, evaluate, and overcome the aftermaths of
different production systems—chemical, physical and biological—has gained rele-
vance with the increasing environmental awareness and ever increasing instances of
natural disasters (Kellenberger and Althaus, 2009). The UN Earth Summit held at
1992 envisaged the significance of critically evaluating every input and output fac-
tor of a process to lay down the ups and downs associated with every industrial pro-
cess (Jensen, 1992). Such an analysis would enable to identify the critical risk
factors linked with any procedure and compare the suitability of different techni-
ques. Moreover, such an analysis could also direct our efforts and research to the
improvement and development of alternate eco-friendly and sometimes cost-
effective strategies leading to productive results (Sepp¨ al¨ a et al., 2001; Miettinen
and Hamalainen, 1997).
Lack of expertise in LCA, unreliability of data due to quality as well as regional
variations, high cost of LCA, restricted or unfriendly access to different LCA meth-
ods, and inadequate provision to address unexpected risk events apart from normal
operative conditions often nullify or diminish the advantages of LCA (DEAT,
2004; Finnveden, 2000). The environmental conditions in different continents vary
and thus generalization of any process would be unwise. As noted in a study on
LCA of household detergents in Europe, the high-energy requirement attributed to
heat water during washing is not found in tropical countries. Therefore the associa-
tion of increased risk factors with use rather than the production of detergents could
be neglected in a different country. Furthermore, drastic environmental depleting
effects of various products used in the production and disposal of xenobiotics would
thus gain light than the factors, such as increased energy requirement. It is also true
that even secondary factors, such as washing machines, could drastically contribute
to the LCA (Cullen and Allwood, 2009). Another drawback associated with LCA is
the inconsistency in the data provided in various LCA, making it difficult to com-
pare the data of various studies even in a particular geographical continent (Curran,
2014).

23.4 Industrial production and life-cycle analysis
of synthetic surfactants

The industrial synthesis of surfactants mostly depends on the chemical synthesis or
modification of different petroleum derived by-products to surface active mole-
cules. The individual surfactants are generally classified as anionic, cationic, non-
ionic, and amphoteric surfactants based on their overall charge. The synthesis of
individual surfactants might include simple steps such as that of triglyceride with
NaOH as observed in soaps, or multistep mediated as observed in the synthesis of
linear alkylbenzene sulfonate (Huang, 2008). The latter is synthesized by the addi-
tion of benzene on chlorinated paraffin in presence of hydrochloric acid and further
sulfonation with sulfur trioxide or sulfuric acid. Table 23.1 summarizes the steps
involved in the chemical synthesis of common synthetic detergents. The most