Page 133 - Refining Biomass Residues for Sustainable Energy and Bioproducts

Application of heterogeneous acid catalyst derived from biomass for biodiesel process 103

Table 4.4 Drawbacks, causes, and possible remedies.
S. Drawback Causes Remedy
No.
1 High temperature Catalytic acid site covered Using catalysts which
requirement by product water from are
esterification reaction Water resistant
Having larger
surface area and
pore size
2 Low reaction rate Catalysis occurs on the Using catalysts that
external surface of the have a larger surface
pores area and
interconnected pores
3 Formation of side Use of alcohol in excess Minimizing methanol-
reaction amount to-oil ratio
4 Catalyst deactivation Unrefined feedstock Using catalysts that are
water resistant
5 Leaching of active sites Hydrolyzing ionic group Following proper
by water catalyst preparation
methods

and transforming by-products for reuse are critical to ensure their economic, social,
and environmental sustainability.
Studies on the sulfonation methods of the biomass-derived solid-acid catalyst
should be further expanded to develop nonhazardous, sustainable, and cost-effective
synthesis routes. Investigations on the usage of catalyst with magnetic properties in
biodiesel production are still very rare and are mostly focused on direct sulfona-
tion with sulfuric acid. More researches can be carried out in this area, such as
incorporation of magnetic properties into base catalyst or enhancing the effi-
ciency of sulfonation with other novel methods. As a whole, current researches
that have been conducted are preparatory steps toward reaching the final goal of
more sustainable implementation of heterogeneous catalyst, especially from bio-
mass waste in the commercial biodiesel production industry. Further, cutting-
edge researches on advanced material and greener synthesis routes have the
potential to elevate the usage of these catalysts for biodiesel production to
another high level. Simplicity and cost-effectiveness should also be taken into
account while simultaneously producing catalyst with high catalytic activity and
reusability.

4.9 Conclusion

In this review, it is discussed that the use of low value biomass-based acid catalysts
to produce biodiesel could act as an important factor when it comes to the