Evaluation of adsorption and kinetics of neem leaf
powder (Azadirachta indica) as a bio-sorbent for
desulfurization of dibenzothiophene (DBT) from
synthetic diesel
The need for a sustainable environment has necessitated the development of a green
adsorbent that is efficient, cheap, and readily available to serve as an alternative adsorbent for
the removal of the refractory sulfur-containing compound from diesel. In this current study,
neem-leaf powder (NLP) was activated using H2SO4 and tested in desulfurization adsorption experiments
of synthetic diesel containing Dibenzothiopene (DBT) during a batch operation. The synthetic
diesel contained 0.1 g of DBT in 100 mL of hexane. Before testing, physio-chemical
characteristics of the adsorbent were checked via Fourier transmission infrared (FTIR) spectroscopy
for surface chemistry; via N2 physisorption at 77 K for textural properties; SEM quipped
with EDX for morphology and elemental composition; and XRD for purity and crystallinity. The
results showed that the physico-chemical nature of the adsorbent played a significant role in
enhancing the adsorption capacity of the material for DBT. Activated NLP displayed DBT removal
of 65.78% at 30 �C using 0.8 g of the adsorbent. Furthermore, the behaviour of the adsorbent during
the adsorption could be adequately described using the Freundlich isotherm model. Pseudo-first-order and pseudo-second-order kinetics model describe well the adsorption kinetics of DBT
onto the activated NLP
