In this study,a new tannic acid adsorbent(ethylene glycol diglycidyl ether crosslinked tannic acid,TAEGDE)for adsorptive removal of dyes from water was prepared using EGDE as a cross-linking agent.The resultant TA-EGD...In this study,a new tannic acid adsorbent(ethylene glycol diglycidyl ether crosslinked tannic acid,TAEGDE)for adsorptive removal of dyes from water was prepared using EGDE as a cross-linking agent.The resultant TA-EGDE was in particulate form with rough surface morphology and a diameter ranging from 10 to 30μm.The adsorption performance of the TA-EGDE was evaluated in a flow-through mode using water samples contaminated with methylene blue(MB)and two-component mixed dyes,respectively.The TA-EGDE provided adsorption capacity up to 721.8 mg·g^(-1)at 65°C for MB.It showed a high removal efficiency(99%)of MB(50 mg·L^(-1))from the water sample and could recovery 90%of the adsorbed MB by eluting with acidic ethanol aqueous solution.The excellent adsorption of MB and neutral red on the TA-EGDE may be the result of the synergy of electrostatic interaction andπ-πinteraction.Furthermore,the TA-EGDE could separate dyes from water samples contaminated with twocomponent mixed dyes with a separation coefficient ranging from 1.8 to 36.5.The anionic TA-EGDE would be an effective adsorbent to remove and recycle dyes from the contaminated water.展开更多
In this paper, poly (acrylamide-co-acrylic acid) (P(AM-co-AA)) hydrogel was pre- pared in an aqueous solution by using glow-discharge electrolysis plasma (GDEP) induced copoly- merization of acrylamide (AM) ...In this paper, poly (acrylamide-co-acrylic acid) (P(AM-co-AA)) hydrogel was pre- pared in an aqueous solution by using glow-discharge electrolysis plasma (GDEP) induced copoly- merization of acrylamide (AM) and acrylic acid (AA), in which N,N'-methylenebisacrylamide (MBA) was used as a crosslinker. A mechanism for the synthesis of P(AM-co-AA) hydrogel was proposed. To optimize the synthesis condition, the following parameters were examined in detail: the discharge voltage, discharge time, the content of the crosslinker, and the mass ratio of AM to AA. The results showed that the optimum pH range for cationic dyes removal was found to be 5.0-10.0. The P(AM-co-AA) hydrogel exhibits a very high adsorption potential and the ex- perimental adsorption capacities for Crystal violet (CV) and Methylene blue (MB) were 2974.3 mg/g and 2303.6 mg/g, respectively. The adsorption process follows a pseudo-second-order kinetic model. In addition, the adsorption mechanism of P(AM-co-AA) hydrogel for cationic dyes was also discussed.展开更多
Applying conventional analytical methods,the following results have been found:the satura-tion value of acid--modified multifunction copolyest fibre( acid-modified polyester fibre)is1.74,then this kind of fibre is goo...Applying conventional analytical methods,the following results have been found:the satura-tion value of acid--modified multifunction copolyest fibre( acid-modified polyester fibre)is1.74,then this kind of fibre is good for being dyed medium and light colours with cationicdyes;its level of erystalization is lower than of PET fibre;the third monomer(SIPM)con-tent in the fibre will be reduced by about 8% by the "alkali treatment"in dyeing and finishingprocess:through measuring and analysing the dye-up-take curves of time and temperature ofdyeing the fibre with cationic dyes,we indicate the key factors in dyeing are the 100℃ dyeingtemperature and the time for heat preservation;moveover,adding sodium sulphate will help leveldyeing but lower the dye-uptake.展开更多
In a thin HCl medium,RRS intensities of an alone CS or acidic triphenylmethane dye (TPMD) are very week. However,when TPMD reacts with a CS to form an ion-associate,the RRS intensity is enhanced greatly and a new RRS ...In a thin HCl medium,RRS intensities of an alone CS or acidic triphenylmethane dye (TPMD) are very week. However,when TPMD reacts with a CS to form an ion-associate,the RRS intensity is enhanced greatly and a new RRS spectrum appears. The spectral characteristics of the RRS for the ion-associates and the optimum conditions for the reactions are investigated. The intensity of RRS is directly proportional to the mass concentration of CS in the range of 0—3.5 or 0—5.0 μg/mL. The method has a high sensitivity for the determination of CS,their detection limits are between 3.1 and 9.8 ng/mL depending on the different CS. In this case,most metal and non-metal ions do not interfere,so that the method has a good selectivity. Therefore,a sensitive,selective,simple and rapid method for the determination of CS by RRS is developed. [WT5HZ]展开更多
文摘In this study,a new tannic acid adsorbent(ethylene glycol diglycidyl ether crosslinked tannic acid,TAEGDE)for adsorptive removal of dyes from water was prepared using EGDE as a cross-linking agent.The resultant TA-EGDE was in particulate form with rough surface morphology and a diameter ranging from 10 to 30μm.The adsorption performance of the TA-EGDE was evaluated in a flow-through mode using water samples contaminated with methylene blue(MB)and two-component mixed dyes,respectively.The TA-EGDE provided adsorption capacity up to 721.8 mg·g^(-1)at 65°C for MB.It showed a high removal efficiency(99%)of MB(50 mg·L^(-1))from the water sample and could recovery 90%of the adsorbed MB by eluting with acidic ethanol aqueous solution.The excellent adsorption of MB and neutral red on the TA-EGDE may be the result of the synergy of electrostatic interaction andπ-πinteraction.Furthermore,the TA-EGDE could separate dyes from water samples contaminated with twocomponent mixed dyes with a separation coefficient ranging from 1.8 to 36.5.The anionic TA-EGDE would be an effective adsorbent to remove and recycle dyes from the contaminated water.
基金supported by National Natural Science Foundation of China(No.21367023)Natural Science Foundation of Gansu Province,China(No.1208RJZA161)Key Project of Young Teachers’ Scientific Research Promotion of Northwest Normal University of China(Nos.NWNU-LKQN-10-16 and NWNU-LKQN-12-9)
文摘In this paper, poly (acrylamide-co-acrylic acid) (P(AM-co-AA)) hydrogel was pre- pared in an aqueous solution by using glow-discharge electrolysis plasma (GDEP) induced copoly- merization of acrylamide (AM) and acrylic acid (AA), in which N,N'-methylenebisacrylamide (MBA) was used as a crosslinker. A mechanism for the synthesis of P(AM-co-AA) hydrogel was proposed. To optimize the synthesis condition, the following parameters were examined in detail: the discharge voltage, discharge time, the content of the crosslinker, and the mass ratio of AM to AA. The results showed that the optimum pH range for cationic dyes removal was found to be 5.0-10.0. The P(AM-co-AA) hydrogel exhibits a very high adsorption potential and the ex- perimental adsorption capacities for Crystal violet (CV) and Methylene blue (MB) were 2974.3 mg/g and 2303.6 mg/g, respectively. The adsorption process follows a pseudo-second-order kinetic model. In addition, the adsorption mechanism of P(AM-co-AA) hydrogel for cationic dyes was also discussed.
文摘Applying conventional analytical methods,the following results have been found:the satura-tion value of acid--modified multifunction copolyest fibre( acid-modified polyester fibre)is1.74,then this kind of fibre is good for being dyed medium and light colours with cationicdyes;its level of erystalization is lower than of PET fibre;the third monomer(SIPM)con-tent in the fibre will be reduced by about 8% by the "alkali treatment"in dyeing and finishingprocess:through measuring and analysing the dye-up-take curves of time and temperature ofdyeing the fibre with cationic dyes,we indicate the key factors in dyeing are the 100℃ dyeingtemperature and the time for heat preservation;moveover,adding sodium sulphate will help leveldyeing but lower the dye-uptake.
文摘In a thin HCl medium,RRS intensities of an alone CS or acidic triphenylmethane dye (TPMD) are very week. However,when TPMD reacts with a CS to form an ion-associate,the RRS intensity is enhanced greatly and a new RRS spectrum appears. The spectral characteristics of the RRS for the ion-associates and the optimum conditions for the reactions are investigated. The intensity of RRS is directly proportional to the mass concentration of CS in the range of 0—3.5 or 0—5.0 μg/mL. The method has a high sensitivity for the determination of CS,their detection limits are between 3.1 and 9.8 ng/mL depending on the different CS. In this case,most metal and non-metal ions do not interfere,so that the method has a good selectivity. Therefore,a sensitive,selective,simple and rapid method for the determination of CS by RRS is developed. [WT5HZ]