Armenta et al. (2008) established the creation of the term green analytical chem­istry based on: (1) sample treatment; (2) oriented scanning methodologies; (3) alternatives to toxic reagents; (4) waste minimization; (5) recovery of reagents; (6) online decontamination of wastes; and (7) reagent-free methodologies. Thus, it should be considered that the analysis of biomass should be based on the 12 principles of green chemistry proposed by Anastas and Warner (1998), since the context of its use is reflected in the sustainability of feedstock and processes.

Some of the 12 principles of green chemistry are closely related to the imple­mentation of green analytical methodology, which are as follows: (1) atomic and

energy economy; (2) use of catalytic reactions instead of stoichiometric reactions; (3) decreasing solvent use; and (4) a decrease in residues (Anastas and Warner 1998). The application of these principles will contribute to achieve a more sus­tainable analytical methodology, as can be seen in Fig. 9.

In some cases, it is very difficult to apply all of those principles presented in Fig. 9, because each analytical method has its particularities and limitations. Then, we need to seek other principles as waste prevention, design for energy efficiency, use of real-time analysis for pollution control, and inherently safer chemistry for accident prevention; this strategy will ensure a greener chemical analysis and ana­lytical chemistry.

3 Conclusions

Chemical analysis of biomass is an important branch of analytical chemistry because it can provide information about the constitution of feedstocks, processes, products and by-products, and residues. Analytical techniques are at the core of the analytical laboratory, and the understanding of its principles is necessary for real-world applications. Then, this can be applied on a whole biofuel chain to solve many technical and scientific problems, as: best uses for a biomass, improvement of conversion processes, increase in the quality of biofuel, and control of residues.

Nowadays, green chemistry and sustainability of processes and products are themes that passed from academic discussion to practical use. Then, analytical chemistry as part of chemical sciences should follow this current trend, which can contribute to a bioeconomy based on biomass use instead of non-renewable raw sources, as the oil, and an advance in biomass knowledge to develop their best uses.