Non-dispersive solvent extraction （NDSE） with p-xylene as extractant was employed as a novel separation methodto recover both ρ-toluic （PT） acid and water from purified terephthalic acid （PTA） wastewater. The m...Non-dispersive solvent extraction （NDSE） with p-xylene as extractant was employed as a novel separation methodto recover both ρ-toluic （PT） acid and water from purified terephthalic acid （PTA） wastewater. The mass transport behavior ofPT acid from aqueous solution to ρ-xylene was investigated by experiments and numerical simulation. Experiments showed thatNDSE is feasible and effective. Residual PT acid in the raffinate can be reduced to lower than the permitted limit of wastewaterre-use （100 g/m^3） with extraction time longer than 60 s in industrial conditions. A mathematical model of PT acid mass transportwas developed to optimize the membrane module performance. The model was validated with the experimental results withrelative errors of less than 6%. Numerical analysis for mass transfer through the lumen side, the porous membrane layer, and theshell side showed that PT acid transport in the aqueous solution is the rate determining step. The effects of the membrane andoperating parameters on membrane module performance were investigated by means of computational simulations. The keyparameters suggested for industrial NDSE design are： fiber inner radius r1=200-250 μm, extraction time tc=50-60 s, aqueous/organic volumetric ratio a/o=9.0, and temperature T-318 K.展开更多
By using laser monitoring technique,the solubilities of p -toluic acid in N -methyl-2-pyrrolidone, N,N -dimethylformamide, N,N -dimethylacetamide,chloroform,acetic acid and water are measured in larger temperature int...By using laser monitoring technique,the solubilities of p -toluic acid in N -methyl-2-pyrrolidone, N,N -dimethylformamide, N,N -dimethylacetamide,chloroform,acetic acid and water are measured in larger temperature intervals by synthetic method.As to the solubility of p -toluic acid in water,the experimental and literature data have satisfactory consistency.Given the solubilities of p -toluic acid, a solubility model is proposed. This model is verified by experimental and literature data, and the solubilities calculated by the model show good agreement with experimental and literature data.展开更多
Micro-amount terephthalic acid and 4-carboxybenzaldehyde in p-toluic acids were determined by a reversed-phase ion suppression chromatography.The separation was carried out on a C18column（4.6mm i.d.×150mm）with ...Micro-amount terephthalic acid and 4-carboxybenzaldehyde in p-toluic acids were determined by a reversed-phase ion suppression chromatography.The separation was carried out on a C18column（4.6mm i.d.×150mm）with methanol-water（70∶30）as the mobile phase at a flow rate of 0.8ml/min and with H3PO4 as an inhibitor.The detection wavelength was 240 nm.The relative standard deviation of terephthalic acid and 4-carboxybenzaldehyde are less than 3% and 2%,respectively.The average recoveries were 102.9% and 103.2%,respectively.The detection limit were 0.25 ng and 0.45 ng,respectively.展开更多
The synthetic method for the titled compound composed of reacting p toluic acid with urea in the presence of sulfamic acid in certain solvent.Some factors of effecting on yield are discussed.
基金supported by the National Natural Science Foundation of China(No.20806072)
文摘Non-dispersive solvent extraction （NDSE） with p-xylene as extractant was employed as a novel separation methodto recover both ρ-toluic （PT） acid and water from purified terephthalic acid （PTA） wastewater. The mass transport behavior ofPT acid from aqueous solution to ρ-xylene was investigated by experiments and numerical simulation. Experiments showed thatNDSE is feasible and effective. Residual PT acid in the raffinate can be reduced to lower than the permitted limit of wastewaterre-use （100 g/m^3） with extraction time longer than 60 s in industrial conditions. A mathematical model of PT acid mass transportwas developed to optimize the membrane module performance. The model was validated with the experimental results withrelative errors of less than 6%. Numerical analysis for mass transfer through the lumen side, the porous membrane layer, and theshell side showed that PT acid transport in the aqueous solution is the rate determining step. The effects of the membrane andoperating parameters on membrane module performance were investigated by means of computational simulations. The keyparameters suggested for industrial NDSE design are： fiber inner radius r1=200-250 μm, extraction time tc=50-60 s, aqueous/organic volumetric ratio a/o=9.0, and temperature T-318 K.
文摘By using laser monitoring technique,the solubilities of p -toluic acid in N -methyl-2-pyrrolidone, N,N -dimethylformamide, N,N -dimethylacetamide,chloroform,acetic acid and water are measured in larger temperature intervals by synthetic method.As to the solubility of p -toluic acid in water,the experimental and literature data have satisfactory consistency.Given the solubilities of p -toluic acid, a solubility model is proposed. This model is verified by experimental and literature data, and the solubilities calculated by the model show good agreement with experimental and literature data.
文摘Micro-amount terephthalic acid and 4-carboxybenzaldehyde in p-toluic acids were determined by a reversed-phase ion suppression chromatography.The separation was carried out on a C18column（4.6mm i.d.×150mm）with methanol-water（70∶30）as the mobile phase at a flow rate of 0.8ml/min and with H3PO4 as an inhibitor.The detection wavelength was 240 nm.The relative standard deviation of terephthalic acid and 4-carboxybenzaldehyde are less than 3% and 2%,respectively.The average recoveries were 102.9% and 103.2%,respectively.The detection limit were 0.25 ng and 0.45 ng,respectively.
文摘The synthetic method for the titled compound composed of reacting p toluic acid with urea in the presence of sulfamic acid in certain solvent.Some factors of effecting on yield are discussed.
基金Supported by the National Basic Research Programof China(973 Program)(2003CB716003,2004CB719605)and the Knowledge Innovation Programof the Chinese Academy of Sciences(K2002A12).
