Knetics and product distributions of cellulose decomposition in near-critical water were studied with a continuous flow-type apparatus for supercritical and near-critical water reactions.The experimental temperature r...Knetics and product distributions of cellulose decomposition in near-critical water were studied with a continuous flow-type apparatus for supercritical and near-critical water reactions.The experimental temperature range was from 513?K to 583?K and residence time from 0.5?min to 1.6?min.The effects of temperature and residence time on cellulose residue were demonstrated.The apparent actiation energy evaluated was 147?kJ·mol -1 .In addition,the effects of temperature and residence time on the yield distributions of wter soluble oligomers,glucose and levulose,pyruvic aldehyde,5-hydroxymethyl furfural,furfural were described in detail.The experimental results showed that selective decomposition of cellulose in near critical water was possible.展开更多
An environmentally benign method to accelerate the pinacol rearrangement in high temperature liquid water by the addition of CO2 was proposed.The effects of CO2 initial pressure and temperature on the kinetics of pina...An environmentally benign method to accelerate the pinacol rearrangement in high temperature liquid water by the addition of CO2 was proposed.The effects of CO2 initial pressure and temperature on the kinetics of pinacol rearrangement were studied.The experimental results showed that the reaction rate could be greatly increased with the addition of CO2.The activation energies evaluated were 81.1 kJ·mol-1 without CO2,and 87.1 kJ·mol-1 with CO2 initial pressure at 0.2 MPa,which showed no significant difference.The main by-product was confirmed to be 2,3-dimethyl-3-butadiene by GC/MS and the possible reaction mechanism was proposed.展开更多
文摘Knetics and product distributions of cellulose decomposition in near-critical water were studied with a continuous flow-type apparatus for supercritical and near-critical water reactions.The experimental temperature range was from 513?K to 583?K and residence time from 0.5?min to 1.6?min.The effects of temperature and residence time on cellulose residue were demonstrated.The apparent actiation energy evaluated was 147?kJ·mol -1 .In addition,the effects of temperature and residence time on the yield distributions of wter soluble oligomers,glucose and levulose,pyruvic aldehyde,5-hydroxymethyl furfural,furfural were described in detail.The experimental results showed that selective decomposition of cellulose in near critical water was possible.
文摘An environmentally benign method to accelerate the pinacol rearrangement in high temperature liquid water by the addition of CO2 was proposed.The effects of CO2 initial pressure and temperature on the kinetics of pinacol rearrangement were studied.The experimental results showed that the reaction rate could be greatly increased with the addition of CO2.The activation energies evaluated were 81.1 kJ·mol-1 without CO2,and 87.1 kJ·mol-1 with CO2 initial pressure at 0.2 MPa,which showed no significant difference.The main by-product was confirmed to be 2,3-dimethyl-3-butadiene by GC/MS and the possible reaction mechanism was proposed.
