Oxidation of alkybenzenes PhCH_2R(R=H, CH_3, C_2H_5 and n-C_3H_7) under 1 atm. of O_2 or air catalyzed by iron(Ⅱ, Ⅲ)-2,2'-bipyridine and 1,10-phenanthroline complexes, affords the aryl-substituted ketones and al...Oxidation of alkybenzenes PhCH_2R(R=H, CH_3, C_2H_5 and n-C_3H_7) under 1 atm. of O_2 or air catalyzed by iron(Ⅱ, Ⅲ)-2,2'-bipyridine and 1,10-phenanthroline complexes, affords the aryl-substituted ketones and alcohols with the conversion of 15.00%~34.58% containing of 97.60%~99.80% ketones and alcohols. The turnover numbers of these catalysts are over 3500 mol-cat. ^(-1)for 3.5 h.展开更多
Two new copper complexes based on pyrazole-3-carboxylic acid (H2pca) ligand, Cu(Hpca)2(H2O)2?2H2O (1) and Cu2(pca)2(H2O)4 (2) have been synthesized and fully characterized by single-crystal X-ray diffra...Two new copper complexes based on pyrazole-3-carboxylic acid (H2pca) ligand, Cu(Hpca)2(H2O)2?2H2O (1) and Cu2(pca)2(H2O)4 (2) have been synthesized and fully characterized by single-crystal X-ray diffraction (SXRD), infrared spectroscopy (IR), thermal gravity analysis (TGA), powder X-ray diffraction (PXRD) and elemental analyses. Complex 1 is mononuclear while complex 2 shows a dinuclear structure. Complex 1 crystallizes in the monoclinic system, space group P21/c with Z = 2, a = 6.5591(5), b = 21.696(2), c = 4.9486(2) ?, V = 680.94(9) ?3, F(000) = 366, Dc = 1.745 g/cm3, μ = 1.650 mm-1, the final R = 0.0340 and wR = 0.0792. Complex 2 crystallizes in the monoclinic system, space group P21/n with Z = 2, a = 5.1935(4), b = 9.6052(7), c = 12.7347(9) ?, V = 634.44(8) ?3, F(000) = 420, Dc = 2.195 g/cm3, μ = 3.404 mm-1, the final R = 0.0305 and wR = 0.0653. The three-dimensional frameworks of two complexes are formed by the O?H???O and N?H???O hydrogen bonding interactions. Notably, two copper complexes are further used as catalysts in the oxidation of alkylbenzenes using t-butylhydroperoxide (TBHP) as the oxidant and they exhibit excellent catalytic performance (Conv. up to 98.9%, Sele. up to 98.7%).展开更多
More and more linear alkylbenzene sulfonate (LAS) has contaminated the water and soil ma pollution discharge, making it important to identify the ecological behavior and toxicity of LAS so as to carry out measures tha...More and more linear alkylbenzene sulfonate (LAS) has contaminated the water and soil ma pollution discharge, making it important to identify the ecological behavior and toxicity of LAS so as to carry out measures that will reduce its negative effects on the ecosystem. The ecological behavior of LAS. including degradation, migration, and plant uptake, in both soil-paddy rice and soil-soybean systems was studied. Reduction of LAS in pot and field plots followed the first order reaction kinetics with degradation half-lives of 35-50 days with LAS decreasing to very low concentrations after a season of crop growth. Strong migration ability for LAS was found and the breakthrough time in a 1.5 in soil monolith was significantly shortened to 23 days by preferential flow. Leachate volumes of soil-paddy and soil-soybean systems at preferential breakthrough were much different, while the leachate volumes at equilibrium governed by soil adsorption/desorption processes were very similar. Significant uptake of LAS in both paddy rice and sovbeans was observed in pot and field experiments (P < 0.05). In aquatic culture, 20 μg mL-1 and above of LAS significantly inhibited the growth of paddy seedlings (P < 0.05). The critical concentration for LAS in soil inhibiting the growth and yield of paddy was 160 μg g-1; when higher, there was a strong negative influence, with decreases in height, spike length, and production, when lower than 80 μg g-1, paddy growth was stimulated. There was little effect of LAS on soybeans.展开更多
To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. Methods Forty-eight guinea pigs were divided equally into 4 groups and exposed to P...To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. Methods Forty-eight guinea pigs were divided equally into 4 groups and exposed to PPD (4 mg/kg), LAS (12 mg/kg) and PPD (4 mg/kg) plus LAS (12 mg/kg) for 30 days. The biochemical parameters such as acid phosphatase, gtutathione-s-transferase, glutathione peroxidase, glutathione, lipid peroxidafion and histamine contents in exposed skin were estimated. The histopathological examination of the exposed skin was also carried out. Results The skin enzymes, lipid peroxidation, and histamine increased while glutathione decreased in skin. The simultaneously exposed group showed additive toxic effects. The histopathological examination showed severe hyperkeratosis, thickening of collagen fibres and vacuolisation of epidermal cells in PPD plus LAS exposed skin. Conclusion The findings of the present study suggest that simultaneous exposure to PPD and LAS has additive toxic effects.展开更多
Through the hydrogenation experiments for removal of olefin impurities in effluent mixture obtained from alkylation reactor for linear alkylbenzene synthesis, the reaction kinetics was studied. The experimental result...Through the hydrogenation experiments for removal of olefin impurities in effluent mixture obtained from alkylation reactor for linear alkylbenzene synthesis, the reaction kinetics was studied. The experimental results showed that the catalytic activity of Pd/Al2 O3 among four kinds of catalysts was the highest, and the olefin conversion reached 100%when the reaction temperature was higher than 140 ℃. The kinetic model was established through parameters estimation.The experimental validation of the kinetic model showed that the kinetic model had higher simulation accuracy. The results of prediction by the kinetic model indicated that with the intensification of reaction conditions, the olefin conversion would increase and the bromine index of the linear alkyl benzene would decrease. Under the conditions covering a WHSV of 2.0 h^(-1),a temperature of 90 ℃, and a hydrogen partial pressure of 1.5 MPa, the olefin conversion was 99.67%, and the bromine index of the linear alkyl benzene could be reduced to less than 20.00 mgBr/(100 g).展开更多
Suspension catalytic distillation (SCD) has been developed recently as an innovative technology in catalytic distillation. In this paper, a brief introduction to SCD is given and an equilibrium stage (EQ) modei is dev...Suspension catalytic distillation (SCD) has been developed recently as an innovative technology in catalytic distillation. In this paper, a brief introduction to SCD is given and an equilibrium stage (EQ) modei is developed to simulate this new process for synthesis of linear alkylbenzene (LAB) from benzene and 1-dodecene. Since non-ideality of this reaction systern is not strong, EQ modei developed could be applied to it successfully. Simulation results agree well with experimental data, and indicate some characteristics of SCD process as an advanced technology for the production of LAB: 100% conversion of olefins, low temperature (90-100℃) and low benzene/olefin mole ratio.展开更多
A pot experiment was conducted to study the effect of an anionic surfactant linear alkylbenzene sulfonate(LAS) application on cadmium(Cd)fractions in soils and Cd distribution in different tissues of soybean(Glycine m...A pot experiment was conducted to study the effect of an anionic surfactant linear alkylbenzene sulfonate(LAS) application on cadmium(Cd)fractions in soils and Cd distribution in different tissues of soybean(Glycine max)plants as well as soil pH.Soil samples were treated with three levels of Cd(0,5,and 10 mg kg^(-1))and five levels of LAS(0,5, 15,50,and 100 mg L^(-1)).Results indicated that compared to the control soils(no Cd and no LAS treatment),soil pH increased and available Cd decreased in the soil treated with external Cd and watered with LAS solutions.Meanwhile, soil exchangeable Cd and Cd bound to carbonates decreased;Cd bound to amorphous iron and manganese oxides and Cd bound to organic matter increased.In addition,LAS application could reduce enrichment of Cd in soybean plants, resulting in decreased Cd in the soybean plants.Thus,suitable LAS application could decrease bioavailability and mobility of soil Cd.展开更多
Ergene Basin is one of the most important industrial centers due to the geographical location in Turkey. Uncontrolled and rapidly increasing industrialization brings together a large number of environmental problems i...Ergene Basin is one of the most important industrial centers due to the geographical location in Turkey. Uncontrolled and rapidly increasing industrialization brings together a large number of environmental problems in the basin. In this study, pollution was investigated in the water samples taken at time intervals and different parts of groundwater and surface water resources located within Ergene Basin by methylene blue anionic surfactants (MBAS) analysis method. Turbidity, temperature, pH, electrical conductivity (EC), concentrations of total P and linear alkylbenzene sulfonates (LAS) were simultaneously determined in the investigated water resources. The results were compared with the Turkish Water Pollution Control Regulation specified in the Quality Criteria of the Inland Water Resources according to their class. The total P and LAS concentrations of surface waters are generally higher than groundwater. In terms of LAS concentrations, the groundwater is Ⅰ-Ⅱ class and the surface water is Ⅱ-Ⅳ class.展开更多
For the alkylation of benzene with long-chain olefins, using Hβzeolite catalyst as replacement of HF or AlCl3 has the advantages of no corrosion, less environmental pollution, and much more 2-phenyl isomer, which has...For the alkylation of benzene with long-chain olefins, using Hβzeolite catalyst as replacement of HF or AlCl3 has the advantages of no corrosion, less environmental pollution, and much more 2-phenyl isomer, which has the highest biodegradability and solubility, and better detergent properties among the related isomers. The characterization of the coke shows that the deactivation of catalyst is caused by the jam of bulkier molecules, such as naphthalene, indane and linear alkylbenzenes, which are too big to move quickly in the intracrystalline pores of catalyst. The deactivated catalyst can be regenerated by benzene washing at higher temperature. To make the processes of reaction and regeneration continuous, a novel moving bed reactor is developed. Comparing with the processes with fixed bed reactors, the processes in this work have the advantages of continuous operation, low temperature, low pressure, low mole ratio of benzene to olefins, and high weight hourly space velocity.展开更多
The effectiveness of using acoustical (sonochemical) reactor for degradation of linear alkylbenzen sulfonate (LAS) from aqueous solution was investigated. LASs are anionic surfactants, found in relatively high amo...The effectiveness of using acoustical (sonochemical) reactor for degradation of linear alkylbenzen sulfonate (LAS) from aqueous solution was investigated. LASs are anionic surfactants, found in relatively high amounts in domestic and industrial wastewaters. In this study, experiments on LAS solution were performed using methylene blue active substances (MBAS) method. The effectiveness of acoustical processor reactor for LAS degradation is evaluated with emphasis on the effect of treatment time and initial LAS concentration. Experiments were performed at initial concentrations of 0.2, 0.5, 0.8 and 1.0 mg/L, acoustic frequency of 130 kHz, applied power of 500 W and temperature of 18℃-20℃. At the conditions involved, LAS degradation was found to increase with increasing sonochemical time. In addition, as the concentration increased, the LAS degradation rate decreased in the acoustical processor reactor.展开更多
文摘Oxidation of alkybenzenes PhCH_2R(R=H, CH_3, C_2H_5 and n-C_3H_7) under 1 atm. of O_2 or air catalyzed by iron(Ⅱ, Ⅲ)-2,2'-bipyridine and 1,10-phenanthroline complexes, affords the aryl-substituted ketones and alcohols with the conversion of 15.00%~34.58% containing of 97.60%~99.80% ketones and alcohols. The turnover numbers of these catalysts are over 3500 mol-cat. ^(-1)for 3.5 h.
基金supported by the NNSFC(Nos.21401094 and 21501086)the Project of Shandong Province Higher Educational Science and Technology Program(No.J16LC53)the College Students'Science and Technology Innovation Fund(No.CXCY2017028 and CXCY2017037)
文摘Two new copper complexes based on pyrazole-3-carboxylic acid (H2pca) ligand, Cu(Hpca)2(H2O)2?2H2O (1) and Cu2(pca)2(H2O)4 (2) have been synthesized and fully characterized by single-crystal X-ray diffraction (SXRD), infrared spectroscopy (IR), thermal gravity analysis (TGA), powder X-ray diffraction (PXRD) and elemental analyses. Complex 1 is mononuclear while complex 2 shows a dinuclear structure. Complex 1 crystallizes in the monoclinic system, space group P21/c with Z = 2, a = 6.5591(5), b = 21.696(2), c = 4.9486(2) ?, V = 680.94(9) ?3, F(000) = 366, Dc = 1.745 g/cm3, μ = 1.650 mm-1, the final R = 0.0340 and wR = 0.0792. Complex 2 crystallizes in the monoclinic system, space group P21/n with Z = 2, a = 5.1935(4), b = 9.6052(7), c = 12.7347(9) ?, V = 634.44(8) ?3, F(000) = 420, Dc = 2.195 g/cm3, μ = 3.404 mm-1, the final R = 0.0305 and wR = 0.0653. The three-dimensional frameworks of two complexes are formed by the O?H???O and N?H???O hydrogen bonding interactions. Notably, two copper complexes are further used as catalysts in the oxidation of alkylbenzenes using t-butylhydroperoxide (TBHP) as the oxidant and they exhibit excellent catalytic performance (Conv. up to 98.9%, Sele. up to 98.7%).
基金Project supported by the National Natural Science Foundation of China (Nos. 49771044 and 49971038)
文摘More and more linear alkylbenzene sulfonate (LAS) has contaminated the water and soil ma pollution discharge, making it important to identify the ecological behavior and toxicity of LAS so as to carry out measures that will reduce its negative effects on the ecosystem. The ecological behavior of LAS. including degradation, migration, and plant uptake, in both soil-paddy rice and soil-soybean systems was studied. Reduction of LAS in pot and field plots followed the first order reaction kinetics with degradation half-lives of 35-50 days with LAS decreasing to very low concentrations after a season of crop growth. Strong migration ability for LAS was found and the breakthrough time in a 1.5 in soil monolith was significantly shortened to 23 days by preferential flow. Leachate volumes of soil-paddy and soil-soybean systems at preferential breakthrough were much different, while the leachate volumes at equilibrium governed by soil adsorption/desorption processes were very similar. Significant uptake of LAS in both paddy rice and sovbeans was observed in pot and field experiments (P < 0.05). In aquatic culture, 20 μg mL-1 and above of LAS significantly inhibited the growth of paddy seedlings (P < 0.05). The critical concentration for LAS in soil inhibiting the growth and yield of paddy was 160 μg g-1; when higher, there was a strong negative influence, with decreases in height, spike length, and production, when lower than 80 μg g-1, paddy growth was stimulated. There was little effect of LAS on soybeans.
文摘To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. Methods Forty-eight guinea pigs were divided equally into 4 groups and exposed to PPD (4 mg/kg), LAS (12 mg/kg) and PPD (4 mg/kg) plus LAS (12 mg/kg) for 30 days. The biochemical parameters such as acid phosphatase, gtutathione-s-transferase, glutathione peroxidase, glutathione, lipid peroxidafion and histamine contents in exposed skin were estimated. The histopathological examination of the exposed skin was also carried out. Results The skin enzymes, lipid peroxidation, and histamine increased while glutathione decreased in skin. The simultaneously exposed group showed additive toxic effects. The histopathological examination showed severe hyperkeratosis, thickening of collagen fibres and vacuolisation of epidermal cells in PPD plus LAS exposed skin. Conclusion The findings of the present study suggest that simultaneous exposure to PPD and LAS has additive toxic effects.
文摘Through the hydrogenation experiments for removal of olefin impurities in effluent mixture obtained from alkylation reactor for linear alkylbenzene synthesis, the reaction kinetics was studied. The experimental results showed that the catalytic activity of Pd/Al2 O3 among four kinds of catalysts was the highest, and the olefin conversion reached 100%when the reaction temperature was higher than 140 ℃. The kinetic model was established through parameters estimation.The experimental validation of the kinetic model showed that the kinetic model had higher simulation accuracy. The results of prediction by the kinetic model indicated that with the intensification of reaction conditions, the olefin conversion would increase and the bromine index of the linear alkyl benzene would decrease. Under the conditions covering a WHSV of 2.0 h^(-1),a temperature of 90 ℃, and a hydrogen partial pressure of 1.5 MPa, the olefin conversion was 99.67%, and the bromine index of the linear alkyl benzene could be reduced to less than 20.00 mgBr/(100 g).
基金Major State Basic Research Development Program(No.G2000048006)
文摘Suspension catalytic distillation (SCD) has been developed recently as an innovative technology in catalytic distillation. In this paper, a brief introduction to SCD is given and an equilibrium stage (EQ) modei is developed to simulate this new process for synthesis of linear alkylbenzene (LAB) from benzene and 1-dodecene. Since non-ideality of this reaction systern is not strong, EQ modei developed could be applied to it successfully. Simulation results agree well with experimental data, and indicate some characteristics of SCD process as an advanced technology for the production of LAB: 100% conversion of olefins, low temperature (90-100℃) and low benzene/olefin mole ratio.
基金the National Natural Science Foundation of China(No.20677080)the Innovation Foundation of Hunan Agricultural University(No.04PT02)
文摘A pot experiment was conducted to study the effect of an anionic surfactant linear alkylbenzene sulfonate(LAS) application on cadmium(Cd)fractions in soils and Cd distribution in different tissues of soybean(Glycine max)plants as well as soil pH.Soil samples were treated with three levels of Cd(0,5,and 10 mg kg^(-1))and five levels of LAS(0,5, 15,50,and 100 mg L^(-1)).Results indicated that compared to the control soils(no Cd and no LAS treatment),soil pH increased and available Cd decreased in the soil treated with external Cd and watered with LAS solutions.Meanwhile, soil exchangeable Cd and Cd bound to carbonates decreased;Cd bound to amorphous iron and manganese oxides and Cd bound to organic matter increased.In addition,LAS application could reduce enrichment of Cd in soybean plants, resulting in decreased Cd in the soybean plants.Thus,suitable LAS application could decrease bioavailability and mobility of soil Cd.
文摘Ergene Basin is one of the most important industrial centers due to the geographical location in Turkey. Uncontrolled and rapidly increasing industrialization brings together a large number of environmental problems in the basin. In this study, pollution was investigated in the water samples taken at time intervals and different parts of groundwater and surface water resources located within Ergene Basin by methylene blue anionic surfactants (MBAS) analysis method. Turbidity, temperature, pH, electrical conductivity (EC), concentrations of total P and linear alkylbenzene sulfonates (LAS) were simultaneously determined in the investigated water resources. The results were compared with the Turkish Water Pollution Control Regulation specified in the Quality Criteria of the Inland Water Resources according to their class. The total P and LAS concentrations of surface waters are generally higher than groundwater. In terms of LAS concentrations, the groundwater is Ⅰ-Ⅱ class and the surface water is Ⅱ-Ⅳ class.
文摘For the alkylation of benzene with long-chain olefins, using Hβzeolite catalyst as replacement of HF or AlCl3 has the advantages of no corrosion, less environmental pollution, and much more 2-phenyl isomer, which has the highest biodegradability and solubility, and better detergent properties among the related isomers. The characterization of the coke shows that the deactivation of catalyst is caused by the jam of bulkier molecules, such as naphthalene, indane and linear alkylbenzenes, which are too big to move quickly in the intracrystalline pores of catalyst. The deactivated catalyst can be regenerated by benzene washing at higher temperature. To make the processes of reaction and regeneration continuous, a novel moving bed reactor is developed. Comparing with the processes with fixed bed reactors, the processes in this work have the advantages of continuous operation, low temperature, low pressure, low mole ratio of benzene to olefins, and high weight hourly space velocity.
基金Project (No. 85-01-46-3401) supported by the Medical Sciences/ University of Tehran, I.R. Iran
文摘The effectiveness of using acoustical (sonochemical) reactor for degradation of linear alkylbenzen sulfonate (LAS) from aqueous solution was investigated. LASs are anionic surfactants, found in relatively high amounts in domestic and industrial wastewaters. In this study, experiments on LAS solution were performed using methylene blue active substances (MBAS) method. The effectiveness of acoustical processor reactor for LAS degradation is evaluated with emphasis on the effect of treatment time and initial LAS concentration. Experiments were performed at initial concentrations of 0.2, 0.5, 0.8 and 1.0 mg/L, acoustic frequency of 130 kHz, applied power of 500 W and temperature of 18℃-20℃. At the conditions involved, LAS degradation was found to increase with increasing sonochemical time. In addition, as the concentration increased, the LAS degradation rate decreased in the acoustical processor reactor.