TY - JOUR
T1 - Use of HZSM-5 modified with citric acid as acid heterogeneous catalyst for biodiesel production via esterification of oleic acid
AU - Vieira, Sara S.
AU - Magriotis, Zuy M.
AU - Ribeiro, Maria Filipa
AU - Graça, Inês
AU - Fernandes, Auguste
AU - Lopes, José Manuel F.M.
AU - Coelho, Sabrina M.
AU - Santos, Nadiene Ap V.
AU - Saczk, Adelir Ap
PY - 2015/1/1
Y1 - 2015/1/1
N2 - In this study, the efficiency of citric acid as dealumination agent was evaluated in the case of zeolite HZSM-5 by varying the experimental conditions, namely concentration (0.5, 1.0 and 2.0 mol L-1) and treatment temperature (60 and 80 °C). The effect of the CA treatment on structural, textural and acidity properties of the starting HZSM-5 material was monitored using XRD, N2 sorption and FTIR (pyridine and collidine) measurements. Heptane and methylcyclohexane cracking model reactions were used to evaluate the catalytic behavior of the modified materials, in terms of acid strength and active sites accessibility. The modified catalysts were tested in the esterification reaction, using oleic acid as reagent and different oleic acid/methanol molar ratios. All the results show the beneficial effect of the citric acid treatment on the physicochemical properties of the final materials, with an improvement of the external acidity, a crucial parameter for the reaction considered, i.e. the oleic acid esterification.
AB - In this study, the efficiency of citric acid as dealumination agent was evaluated in the case of zeolite HZSM-5 by varying the experimental conditions, namely concentration (0.5, 1.0 and 2.0 mol L-1) and treatment temperature (60 and 80 °C). The effect of the CA treatment on structural, textural and acidity properties of the starting HZSM-5 material was monitored using XRD, N2 sorption and FTIR (pyridine and collidine) measurements. Heptane and methylcyclohexane cracking model reactions were used to evaluate the catalytic behavior of the modified materials, in terms of acid strength and active sites accessibility. The modified catalysts were tested in the esterification reaction, using oleic acid as reagent and different oleic acid/methanol molar ratios. All the results show the beneficial effect of the citric acid treatment on the physicochemical properties of the final materials, with an improvement of the external acidity, a crucial parameter for the reaction considered, i.e. the oleic acid esterification.
KW - Biodiesel
KW - Citric acid
KW - Dealumination
KW - Esterification
KW - HZSM-5
UR - http://www.scopus.com/inward/record.url?scp=84926216428&partnerID=8YFLogxK
U2 - 10.1016/j.micromeso.2014.09.015
DO - 10.1016/j.micromeso.2014.09.015
M3 - Article
AN - SCOPUS:84926216428
SN - 1387-1811
VL - 201
SP - 160
EP - 168
JO - Microporous and Mesoporous Materials
JF - Microporous and Mesoporous Materials
IS - C
ER -