A Study of Adsorption Kinetics of β-phenylaminopropiophenone on Iron in Acid Solution

用计时电流法研究了０．５ｍｏｌ／ＬＨ２ＳＯ４溶液中β－苯胺基苯丙酮（ＰＡＰ）、卤素离子（Ｃｌ－，Ｉ－）在铁电极上的吸附动力学行为以及Ｃｌ－对ＰＡＰ吸、脱附速度的影响，求得了吸、脱附速度常数ｋａ、ｋｄ和吸附自由能参数ｆ值．结果表明，当ＰＡＰ发生化学吸附时，ｋａ比ｋｄ约大２个数量级，吸附粒子间存在吸引力．在电极表面已吸附有Ｃｌ－的条件下，且当ＰＡＰ浓度较低时发生静电吸附，ｋａ比ｋｄ约大４个数量级，吸附粒子间存在排斥力；浓度高时则发生化学吸附．The adsorption kinetics of β-phenylaminopropiophenone (PAP) on iron electrode in 0.5 mol/L H_2SO_4 solution with or without Cl~- were investigated by chronoamperometry. According to the following adsorption kinetic equation dθ/dt=kaCen-1(1-θ)nexp(fθ/2)-kdθexp(-fθ/2)The rate constants ka, kd as well as the adsorption free energy parameter f of PAP in sulfuric acid soltuion was calculated by used a computerized curve fitting program, the calculated ka, kd are in the order of 10~-1 mol/L s~-1 and 10~-3 s-1, respectively, f>0 in the concentration region of 5×10~-5 to 1×10~-3 mol/L of PAP. While in the 0.5 mol/L H_2SO_4 solution with 0.1 mol/L Cl-,the values of ka, kd are 66 mol/L s~-1 and 1.8×10~-3 s-1, respectively, f0 when CPAP=1×10~-3 mol/L. Otherwhere, authors proved that the PAP occurred electrostatic adsorption under former condition, and it is chemisorbed on the iron surface under latter condition.作者联系地址：武汉大学环境科学系Author's Address: Dept. of Envir. Sci., Wuhan Univ., Wuhan 43007

The Adsorption desorption Behaviors of β phenylaminopropiophenone on iron in sulphuric acid solution

用极化曲线法研究了０．５ｍｏｌ·Ｌ－１硫酸溶液中β－苯胺基苯丙酮（ＰＡＰ）在铁－溶液界面的吸脱附行为及Ｃｌ－，Ｉ－的影响．结果表明，ＰＡＰ的吸附遵循Ｆｌｏｒｙ－Ｈｕｇｇｎｓ等温式；在较正的极化电位区出现阳极脱附现象．讨论了两种粒子联合吸附方式与浓度的关系，提出可根据吸附粒子的脱附电位与其浓度关系来推断联合吸附的理论模型The adsorption desorption behaviors of β phenylaminopropiophenone (PAP) on iron in 0.5 mol·L -1 H 2SO 4 solution with or without halide ions (Cl -,I -) were investigated by potentiostatic polarization measurement. The results show that the adsorption of PAP on iron surface follows Flory Huggins isotherm, the adsorption free energy parameter ( f ) is positive in H 2SO 4 solution; In the presence of 0.1 mol·L -1 Cl -1 , when C PAP ≤2×10 -5 mol·L -1 , f0 . A desorption phenomenon was observed at more positive potential region in anodic polarization curves. Furthermore, the anodic desorption potential ( E des ) of PAP+X - is independent of PAP concentration at lower concentration region, and E des vs. lg C PAP is a straight line at higher concentration region. The joint adsorption modes under different conditions were determined according to the above stated relation of E des to PAP concentrations as well as the adsorption free energy parameter f values.作者联系地址：武汉大学环境科学系Author's Address: Department of Environmental science, Wuhan University, Wuhan 43007

Studies on Electrochemical Synthesis of 4,5-Disubstituted-1,2- Benzoquinones and the Reaction Mechanism

邻苯二酚在不同亲核试剂存在下经电解氧化 ,一步合成了 4,5_二取代_1,2_苯醌类化合物 ;对电解氧化_迈克尔加成反应进行了探讨 ,提出了可能的反应历程 .The oxidation peak potentials( E p) of alinine derivates and catechol in 0.1 mol/L KCl+15% alcohol solution were measured by cyclic voltammograms technique. The electrochemical oxidation condition was set according to the E p. Three derivates of 4,5_disubstituted _1,2_benzoquinones were prepared via electrochemical oxidation_Michael addition reaction. The possible mechanism of electrochemical oxidation_Michael addition reaction is presented.作者联系地址：中山大学化学与化学工程学院!广东广州510275,中山大学化学与化学工程学院!广东广州510275,中山大学化学与化学工程学院!广东广州510275,中山大学化学与化学工程学院!广东广州510275,中山大学化学与化学工程学院!广东广州510275Author's Address: Inst.of Chem. and Chem. Engin. of Zhongshan Univ., Guangzhou 510275,China$$