Glucose To Restore The Preparation Of Cuprous Oxide

Cuprous oxide is an important inorganic industrial chemical and widely applied in many fields.Among the main preparation methods of Cu₂O particles,the liquid phase methods are most widely investigated because their advantages those equipments are simple and control of particle morphology and size is easy.However,the use of poisonous chemicals as reductants such as N₂H₄ and Na₂SO₃ causes a high environmental protection costs in many processes.The purpose of this work is to development a green production process of Cu₂O particle using glucose as a reduction agent.In this work,Cu₂O particles were prepared via reducing 1.0mol/L Cu(Ⅱ) with glucose under alkaline condition without any additive,using rising temperature method and constant temperature method.In the rising temperature method,the reactants are mixed at room temperature at first, then rise to reaction end-point temperature at a constant temperature rising rate.In the constant temperature method,the reactants are mixed at given temperature and then react.The results are summarized as follows:Concerning the preparation of Cu₂O particles with rising temperature method,the influence of the reaction end-point temperature, the glucose concentration and stiring rate on the morphology and size of Cu₂O particles were studied.The results show that the morphology of Cu₂O particles is not remarkably affected by the end-point temperature change from 50℃to 80℃and spherical particles are obtained as a result of aggregation growth mode.The average size of Cu₂O particles first increases and then decreases with increasing temperature,but change in the average size is not wide(0.68μm to 0.95μm).When glucose concentration changed from 1.0 mol/L to 2.0mol/L,the spherical Cu₂O particles with average size 0.99μm to 0.74μm are obtained as a result of aggregation growth mode.The average size of Cu₂O particles becomes smaller and more uniform with increasing the glucose concentration. When the glucose concentration was 0.5mol/L,the cubic Cu₂O particles were obtained as a result of two-dimensional nucleation growth mode. The stiring rate has ruleless effect on the size of Cu₂O particles at the rage of 200rpm to 600rpm.The average sizes of Cu₂O particles among 0.6～1.0μm were obtained with this method,but the larger sizes of Cu₂O particles are hardly obtained.Concerning the preparation of Cu₂O particles with constant temperature method,the influence of adding mode of reagents,reaction temperature,reaction time and glucose concentration on Cu₂O particles were studied.The results show that the adding mode of reagents has important effect on the dispersibility of Cu₂O particles.The dispersibility of Cu₂O particles is the best when the glucose reduction is carried out after mixing CuSO₄ with NaOH.The average sizes of Cu₂O particles become smaller with increasing temperature.The spherical Cu₂O particles were obtained as a result of aggregation growth mode,and Cu₂O particles average size is 1.42μm to 0.78μm at the range of 40 to 60℃. Mixture of spherical and cubic Cu₂O particles was obtained as a result of the two-dimensional and dislocation growth modes accompanying with a temperature higher than 60℃.Prolonging reaction time slightly affect the morphology and size of Cu₂O particles at the rage of 20min to 120min. The glucose concentration significantly affects the morphology and size of Cu₂O particles.The dominant growth mode of Cu₂O crystal converted from dislocation growth to two-dimensional growth and aggregation growth and the morphology of Cu₂O particles changed from octahedron through similar spherical,mixture of cube and sphere to sphere when glucose concentration changed gradually from 0.25mol/L to 2.0mol/L. The sizes of Cu₂O particles become smaller with increasing the glucose concentration.Spherical Cu₂O particles of 2.71μm to 1.08μm were obtained when glucose concentration changed from 0.4mol/L to 2.0mol/L.Comparing two methods,the constant temperature method has advantages that the condition controlling is simpler and obtained Cu₂O particles are more uniform.