(729i) Production of Bio-Diesel Additives from Dairy Manure in Supercritical Ethanol

Production of
Bio-diesel Additives from Dairy Manure in Supercritical Ethanol

Xiaokun Yang¹,
Mi Lu¹, Marcus Vinicius
Pereira¹, Simon Poulson³, Charles Coronella¹, and
Hongfei Lin^1*

¹Chemical Engineering and
Materials Science Department, ²Agriculture, Biotechnology &
Natural Resources Department, ³Geological Sciences & EngineeringDepartment,

University
of Nevada, Reno, NV, U.S 89557

E-Mail: HongfeiL@unr.edu

Dairy manure is regarded as a waste material
that needs substantial waste management. However, as the biomass feedstock it contains
lipid, protein, lignin, hemicellulose, and cellulose, which can be used to
produce value-added chemicals. Herein, dried dairy manure was converted in
ethanol and ethanol-water solutions at near supercritical conditions. The
highest conversion of manure reached to 72% (ash free) under supercritical
ethanol at 245°C. In the presence of solid Lewis acid catalysts, Zr-KIT-6 or
hydrated niobia, ethyl esters from cellulose,
hemicellulose and lignin were the main products, which can be used as biodiesel
additives. It was found that adding 5-10 % water in ethanol enhanced the
decomposition of recalcitrant cellulose and lignin, and thus increased the
manure conversion and the overall yields of ethyl esters. Various process
conditions including temperature, pressure, biomass-to-catalyst ratio,
water-to-ethanol ratio, etc. were examined and optimized. High-loading amounts
of manure were used in this process which makes the catalytic process promising
for future's scale-up to industrial scale. Lastly, the possible reaction
mechanism based on Lewis acid catalysis in supercritical ethanol-water solvents
was discussed.