The physicochemical properties
of the raw biomass and hydrochars obtained under RSM- and GA-optimized
conditions were measured and compared. The proximate analysis, which
measures the sample’s inherent moisture, ash content, and volatile
matter, with the fixed carbon determined by the difference, was carried
out in accordance with the ASTM D-5142 standard. The CV was measured
for the samples using a Leco AC500 bomb calorimeter in accordance
with the ASTM D5865-04 standard. The ultimate and sulfur analyses
of all the samples were performed according to ASTM D 5373-02 and
ASTM D 4239-05 for CHN and total sulfur content, respectively, using
a Leco CHN 628 with an add-on 628 S module.
The raw biomass
and the optimized hydrochars were converted to ash following the CEN/TS
14588 standard, with inductively coupled plasma atomic emission spectroscopy
(ICP-AES) used to characterize the ash for heavy metals. The combustion
and co-combustion tests were conducted under an oxidizing atmosphere
using air. Approximately 100 mg of each sample was subjected to a
heating rate of 10 °C/min from room temperature to 850 °C
and held until there was a constancy in weight loss. Individual DTG
curves obtained from the combustion of the samples were used to evaluate
the sample’s combustion properties, including the initiation
of volatile matter, ITFC, peak temperature, and BT. The
BET surface area and pore volume were determined using an Autosorb
iQ-C automated gas sorption analyzer. The surface morphology was determined
and elemental analysis was performed using a Carl Zeiss Sigma Field
Emission Scanning Electron Microscope equipped with an Oxford X-act
EDS detector and transmission electron microscope FEI—Quanta
250. The functional groups were determined using a Perkin Elmer FTIR
Spectrometer—Spectrum Two over the wavenumber range of 400–4000
cm–1. The X-ray powder diffraction analysis was
conducted using a D2 PHASER Bruker Meas Srv D2-208365 with SSD 160
operated at 30 kV and 10 mA.
The MY of the hydrochars was calculated
using the following equations where MY is the mass yield, MHC is the mass of the hydrochar, and MB is the mass of the biomass sample.
of the raw biomass and hydrochars obtained under RSM- and GA-optimized
conditions were measured and compared. The proximate analysis, which
measures the sample’s inherent moisture, ash content, and volatile
matter, with the fixed carbon determined by the difference, was carried
out in accordance with the ASTM D-5142 standard. The CV was measured
for the samples using a Leco AC500 bomb calorimeter in accordance
with the ASTM D5865-04 standard. The ultimate and sulfur analyses
of all the samples were performed according to ASTM D 5373-02 and
ASTM D 4239-05 for CHN and total sulfur content, respectively, using
a Leco CHN 628 with an add-on 628 S module.
The raw biomass
and the optimized hydrochars were converted to ash following the CEN/TS
14588 standard, with inductively coupled plasma atomic emission spectroscopy
(ICP-AES) used to characterize the ash for heavy metals. The combustion
and co-combustion tests were conducted under an oxidizing atmosphere
using air. Approximately 100 mg of each sample was subjected to a
heating rate of 10 °C/min from room temperature to 850 °C
and held until there was a constancy in weight loss. Individual DTG
curves obtained from the combustion of the samples were used to evaluate
the sample’s combustion properties, including the initiation
of volatile matter, ITFC, peak temperature, and BT. The
BET surface area and pore volume were determined using an Autosorb
iQ-C automated gas sorption analyzer. The surface morphology was determined
and elemental analysis was performed using a Carl Zeiss Sigma Field
Emission Scanning Electron Microscope equipped with an Oxford X-act
EDS detector and transmission electron microscope FEI—Quanta
250. The functional groups were determined using a Perkin Elmer FTIR
Spectrometer—Spectrum Two over the wavenumber range of 400–4000
cm–1. The X-ray powder diffraction analysis was
conducted using a D2 PHASER Bruker Meas Srv D2-208365 with SSD 160
operated at 30 kV and 10 mA.
The MY of the hydrochars was calculated
using the following equations where MY is the mass yield, MHC is the mass of the hydrochar, and MB is the mass of the biomass sample.
