Electro Analytical Determination of Di Hydroxybenzene Isomers Using Glassy Carbon Electrode

In this study, the electrochemical oxidation of CT （catechol）, HQ （hydroquinone） and RS （resorcinol） was investigated using cyclic and linear sweep voltammetries at GCE （glassy carbon electrode）. The GCE showed an excellent electro activity and reversibility towards the oxidation of these isomers at different conditions. HQ and CT showed one defined oxidation peak and one defined reduction peak while RS showed one defined oxidation peak. These isomers were determined also in their binary and tertiary mixtures. The calibration curves for CT, HQ and RS were obtained in the ranges of 5 × 10-6 to 1 × 10-3 mol.dm-3, 5 × 10-6 to 5 × 10-4mol.dm-3 and 1 × 10-5 to 1× 10-3 mol.dm-3, respectively. The detection limits were 9 ×10-7, 3 × 10-7, 6 × 10-6 mol.dm3 for CT, HQ and RS, respectively. At the optimal experimental conditions, these isomers were determined in different water samples. Also, the removal of catechol from aqueous solution by adsorption on activated charcoal and alumina was studied. After 24 h, 88.7% and 65.9% of catechol was removed using charcoal and alumina, respectively.     

太阳能集热真空膜蒸发系统及其盐溶液浓缩试验

采用太阳能集热真空膜蒸发系统对高浓盐水进行蒸发浓缩试验研究,考察了温度,真空度以及盐水溶液浓度对浓缩效果的影响。结果表明:温度、真空度的提高均能增大膜通量;实验中聚四氟乙烯(PTFE)膜组件的最高膜蒸发浓缩通量可达3.94kg/(m2·h);其中盐水浓度能从7%蒸发浓缩至32%,不产生明显的结晶.太阳能集热装置能维持料液温度在60~80℃范围内,供热稳定性良好,具有放大应用前景.