An environmentally benign oxygenation protocol was developed for selective oxidation of some types of aromatic and aliphatic sulfides in good to excellent yields utilizing 34% hydrogen peroxide catalyzed by simple het...An environmentally benign oxygenation protocol was developed for selective oxidation of some types of aromatic and aliphatic sulfides in good to excellent yields utilizing 34% hydrogen peroxide catalyzed by simple heteropolyoxometalates in normal drinking water at room temperature. The catalysts could be recovered and reused for at least seven reaction cycles under the described reaction conditions without considerable loss of reactivity. This procedure introduced a new insight into the use of simple heteropolyanions as recoverable catalysts for the oxidation of organic sulfides by an environmentally acceptable protocol. Keywords展开更多
Free gold and gold wrapped in sulfides are considered as the object of gold floatation. However,floatation of free gold exhibits more variables in practice.In this study, improving gold recovery of a Pb-Zn sulfide ore...Free gold and gold wrapped in sulfides are considered as the object of gold floatation. However,floatation of free gold exhibits more variables in practice.In this study, improving gold recovery of a Pb-Zn sulfide ore from Yunnan Province, China, was investigated. The results show that free gold and auriferous sulfides account for 94.99 % of total gold. Without adding organic acid in floatation, only 82 % recovery of gold could be obtained.Gold recovery in Au/Pb concentrates increases by 9.29 %with oxalate added and by 7.35 % with citric acid added,respectively, while performances of lead and arsenic nearly keep a constant. A possible reason is that free gold is of wonderful selectivity against pyrite with organic activators.A new method to enhance gold recovery is proposed.展开更多
Metal sulfides as a feasible candidate with high specific capacitance for supercapacitors suffer from sluggish ion/electron transport kinetics and rapid capacitance fading. Herein, we demonstrate a method to fabricate...Metal sulfides as a feasible candidate with high specific capacitance for supercapacitors suffer from sluggish ion/electron transport kinetics and rapid capacitance fading. Herein, we demonstrate a method to fabricate a composite of reduced graphene oxide（rGO） with hollow Co9S8 derived from metal organic framework（MOF）. Due to the combined highly conductive rGO substrates and hollow shell, the prepared r GO/Co9S8 composite exhibits a high specific capacitance of 575.9 F/g at 2 A/g and 92.0% capacitance retention after 9000 cycles. Its excellent electrochemical performance provides great promise for application, and this versatile method can be extended to prepare other similar nanocomposite.展开更多
文摘An environmentally benign oxygenation protocol was developed for selective oxidation of some types of aromatic and aliphatic sulfides in good to excellent yields utilizing 34% hydrogen peroxide catalyzed by simple heteropolyoxometalates in normal drinking water at room temperature. The catalysts could be recovered and reused for at least seven reaction cycles under the described reaction conditions without considerable loss of reactivity. This procedure introduced a new insight into the use of simple heteropolyanions as recoverable catalysts for the oxidation of organic sulfides by an environmentally acceptable protocol. Keywords
基金financially supported by the National Natural Science Foundation of China(No.51374247)
文摘Free gold and gold wrapped in sulfides are considered as the object of gold floatation. However,floatation of free gold exhibits more variables in practice.In this study, improving gold recovery of a Pb-Zn sulfide ore from Yunnan Province, China, was investigated. The results show that free gold and auriferous sulfides account for 94.99 % of total gold. Without adding organic acid in floatation, only 82 % recovery of gold could be obtained.Gold recovery in Au/Pb concentrates increases by 9.29 %with oxalate added and by 7.35 % with citric acid added,respectively, while performances of lead and arsenic nearly keep a constant. A possible reason is that free gold is of wonderful selectivity against pyrite with organic activators.A new method to enhance gold recovery is proposed.
基金Financial support from National Key Project (No. 2017YFF0210703)Distinguished Young Scientists Program of the National Natural Science Foundation of China (Nos. 51425301, 21374021, 51673096 and U1601214)
文摘Metal sulfides as a feasible candidate with high specific capacitance for supercapacitors suffer from sluggish ion/electron transport kinetics and rapid capacitance fading. Herein, we demonstrate a method to fabricate a composite of reduced graphene oxide（rGO） with hollow Co9S8 derived from metal organic framework（MOF）. Due to the combined highly conductive rGO substrates and hollow shell, the prepared r GO/Co9S8 composite exhibits a high specific capacitance of 575.9 F/g at 2 A/g and 92.0% capacitance retention after 9000 cycles. Its excellent electrochemical performance provides great promise for application, and this versatile method can be extended to prepare other similar nanocomposite.
