Experiments were conducted to study the catalytic esterification of acetic acid which was regarded as the model compound of bio-oil. The solid super-acid
SO
4
2-
/SiO
2
-TiO
2
was selected as the catalyst and the conversion rate of acetic acid was viewed as the evaluating indicator. The effects of various factors like temperature
the mass ratio of ethanol to acetic acid
and the catalyst amount were examined. On the basis of experimental data
the least square support vector machine was applied to build a model of the intelligent prediction of the conversion rate of acetic acid
and the adaptive particle swarm algorithm was used to optimize the parameters in the least square support vector machine. The results indicate that the optimal catalytic esterification of bio-oil would opera
te at the temperature of 80 ℃
the mass ratio of ethanol to acetic acid of 1.6
and the catalyst content of 7.5%. By the examination of 15 testing samples
the prediction error(absolute average relative error)of the least square support vector machine decreases to 9.7%
showing that the least square support vector machine is more suitable for predicting the conversion rate of acetic acid during the catalytic esterification process of bio-oil than the conventional BP or RBF neural network.
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