A series of natural product 23-hydroxybetulinic acid derivatives were prepared. In the preparation of mono-O-benzoyl ester derivative, it was observed that benzoyl group migrated from 3-0- to 23-O-position during the ...A series of natural product 23-hydroxybetulinic acid derivatives were prepared. In the preparation of mono-O-benzoyl ester derivative, it was observed that benzoyl group migrated from 3-0- to 23-O-position during the detritylation.展开更多
Treatment of yellow dye 23 by heterogeneous Fenton-like process was studied using iron rich soil as an iron source. The iron rich soil sample was characterized by XRD, SEM and BET analysis. XRD pattern indicates that ...Treatment of yellow dye 23 by heterogeneous Fenton-like process was studied using iron rich soil as an iron source. The iron rich soil sample was characterized by XRD, SEM and BET analysis. XRD pattern indicates that the iron rich soil is made of goethite and hematite. The reaction was systematically investigated under various experimental conditions such as pH, iron rich soil dosage, oxidant and dye concentrations. The result revealed that using iron rich soil as catalyst led to high discoloration efficiency (97.71% for 140 min of treatment) at pH = 2.5, 2 g/L iron rich soil and 16 m·mol/L H<sub>2</sub>O<sub>2</sub>. The degradation kinetics of acid yellow 23 can be described by a pseudo-first-order reaction following the Langmuir-Hinshelwood mechanism. The main roles of hydroxyl radicals in degradation process were investigated by adding of various radical scavengers.展开更多
基金supported by the National Natural Science Foundation of the People's Republic of China(No.30472083).
文摘A series of natural product 23-hydroxybetulinic acid derivatives were prepared. In the preparation of mono-O-benzoyl ester derivative, it was observed that benzoyl group migrated from 3-0- to 23-O-position during the detritylation.
文摘Treatment of yellow dye 23 by heterogeneous Fenton-like process was studied using iron rich soil as an iron source. The iron rich soil sample was characterized by XRD, SEM and BET analysis. XRD pattern indicates that the iron rich soil is made of goethite and hematite. The reaction was systematically investigated under various experimental conditions such as pH, iron rich soil dosage, oxidant and dye concentrations. The result revealed that using iron rich soil as catalyst led to high discoloration efficiency (97.71% for 140 min of treatment) at pH = 2.5, 2 g/L iron rich soil and 16 m·mol/L H<sub>2</sub>O<sub>2</sub>. The degradation kinetics of acid yellow 23 can be described by a pseudo-first-order reaction following the Langmuir-Hinshelwood mechanism. The main roles of hydroxyl radicals in degradation process were investigated by adding of various radical scavengers.
