Ball milling as an important pretreatment technique in lignocellulose biorefineries: a review
byY. Sitotaw, N. Habtu, A. Y. Gebreyohannes, S. P. Nunes
Year:2021DOI:10.1007/s13399-021-01800-7
Bibliography
Biomass Conversion and Biorefinery
Extra Information
Biomass Conversion and Biorefinery 2021
Abstract
The conversion of lignocellulosic biomass into bioethanol remains a
challenging process due to the recalcitrant structure of lignocellulose.
The presence of the sturdy lignin protective sheath, complex structure,
and partial crystallinity of cellulose often reduces the enzymatic
susceptibility of lignocellulosic biomass. Therefore, pretreatment is
aimed to increase accessibility by improving the physicochemical
properties and composition of lignocellulosic biomass. It is the first
and the most critical step that needs to be carefully selected and
designed to overcome the constraints and improve the overall efficiency
of bioethanol production. In recent years, ball milling has been applied
as an emerging technique to produce bioethanol from lignocellulosic
biomass efficiently and in an environment-friendly manner. Furthermore,
ball milling technique coupled with chemical and physicochemical
pretreatments has been shown to facilitate lignin removal, reduce
cellulose crystallinity, and increase the specific surface area which
ultimately improves the digestibility of lignocellulosic biomass. Over
the last decade, several reports have been published on the application
of ball milling to intensify the pretreatment process. However, a
compiled report showing the progress of the technology in bioethanol
processing is absent. In this review, a critical analysis and evaluation
of published works on ball milling and ball milling–assisted
chemical/physicochemical pretreatments are presented. It also addresses
the synergistic effects of combining ball milling and
chemical/physicochemical treatments to bring desirable characteristics
of lignocellulosic biomass that will eventually improve hydrolysis yield
and reduce chemical and energy consumption in bioethanol production.