The optimal condition for a one-step process removing organic compounds from coking wastewater by simultaneously synthesized organobentonite as a pretreatment was investigated.Results showed that sorption of organic c...The optimal condition for a one-step process removing organic compounds from coking wastewater by simultaneously synthesized organobentonite as a pretreatment was investigated.Results showed that sorption of organic compounds by organobentonite was positively correlated to the cation surfactant exchange on the bentonite and the octanol-water partition coefficient(Kow) of the solutes.With 0.75 g/L bentonite and 180 mg/L(60% of bentonite cation exchange capacity) cetyltrimethylammonium bromide,the removal efficiencies of the 16 polycyclic aromatic hydrocarbon(PAHs) specified by the US Environmental Protection Agency in coking wastewater except naphthalene were more than 90%,and that of benzo(a)pyrene was 99.5%.At the same time,the removal efficiencies of CODCr,NH3-N,volatile phenols,colour and turbidity were 28.6%,13.2%,8.9%,55% and 84.3%,respectively,and the ratio of BOD5/CODCr increased from 0.31 to 0.41.These results indicated that the one-step process had high removal efficiency for toxic and refractory hydrophobic organic compounds,and could improve the biodegradability of the coking wastewater.Therefore it could be a promising technology for the pretreatment of toxic and refractory organic wastewater.展开更多
Formation of super-hydrophobic and corrosion-resistant coatings can provide significant corrosion protection to magnesium alloys.However,it remains a grand challenge to produce such coatings for magnesium-lithium allo...Formation of super-hydrophobic and corrosion-resistant coatings can provide significant corrosion protection to magnesium alloys.However,it remains a grand challenge to produce such coatings for magnesium-lithium alloys due to their high chemical reactivity.Herein,a one-step hydrothermal processing was developed using a stearic-acid-based precursor medium,which enables the hydrothermal conversion and the formation of low surface energy materials concurrently to produce the super-hydrophobic and corrosion-resistant coating.The multiscale microstructures with nanoscale stacks and microscale spheres on the surface,as well as the through-thickness stearates,lead to the super-hydrophobicity and excellent corrosion resistance of the obtained coating.展开更多
AB2-type-prepolymerized monomer was rapidly (2 h) prepared at room temperature (25 ℃) using commercially available maleic anhydride (MA) and diethanolamine (DEA) as raw materials. By employing toluene-p-sulfo...AB2-type-prepolymerized monomer was rapidly (2 h) prepared at room temperature (25 ℃) using commercially available maleic anhydride (MA) and diethanolamine (DEA) as raw materials. By employing toluene-p-sulfonic acid as a catalyzer, a series of hyperbranched poly(amide-ester) (HBPAE) were successfully synthesized from prepared AB2 monomer by solution condensation polymerization through "one-step process" or "pseudo one-step process" (using pentaerythritol as a center core). The processes were carried out at high temperature of 120 ℃ for 6 h in air atmosphere (inert protection free) with reduced pressure distillation (0.08--0.096 MPa). The results of FT-IR, UV-Vis, TGA, and intrinsic viscosity testing by Ubbelodhe viscometer showed that the prepared HBPAEs possess three-dimensional configuration with unsaturated conjugate structure, large numbers of branches and numerous terminal hydroxyl groups. These result in their low viscosity, high solubility and thermal stability.展开更多
基金supported by the National Natural Science Foundation of China (No. 20890111)
文摘The optimal condition for a one-step process removing organic compounds from coking wastewater by simultaneously synthesized organobentonite as a pretreatment was investigated.Results showed that sorption of organic compounds by organobentonite was positively correlated to the cation surfactant exchange on the bentonite and the octanol-water partition coefficient(Kow) of the solutes.With 0.75 g/L bentonite and 180 mg/L(60% of bentonite cation exchange capacity) cetyltrimethylammonium bromide,the removal efficiencies of the 16 polycyclic aromatic hydrocarbon(PAHs) specified by the US Environmental Protection Agency in coking wastewater except naphthalene were more than 90%,and that of benzo(a)pyrene was 99.5%.At the same time,the removal efficiencies of CODCr,NH3-N,volatile phenols,colour and turbidity were 28.6%,13.2%,8.9%,55% and 84.3%,respectively,and the ratio of BOD5/CODCr increased from 0.31 to 0.41.These results indicated that the one-step process had high removal efficiency for toxic and refractory hydrophobic organic compounds,and could improve the biodegradability of the coking wastewater.Therefore it could be a promising technology for the pretreatment of toxic and refractory organic wastewater.
基金support from the Fundamental Research Funds for the Central Universities of Hohai university(B200202122)National Natural Science Foundation of China(51878246 and 51979099)+1 种基金the Natural Science Foundation of Jiangsu Province of China(BK20191303)Key Research and Development Project of Jiangsu Province of China(BE2017148).
文摘Formation of super-hydrophobic and corrosion-resistant coatings can provide significant corrosion protection to magnesium alloys.However,it remains a grand challenge to produce such coatings for magnesium-lithium alloys due to their high chemical reactivity.Herein,a one-step hydrothermal processing was developed using a stearic-acid-based precursor medium,which enables the hydrothermal conversion and the formation of low surface energy materials concurrently to produce the super-hydrophobic and corrosion-resistant coating.The multiscale microstructures with nanoscale stacks and microscale spheres on the surface,as well as the through-thickness stearates,lead to the super-hydrophobicity and excellent corrosion resistance of the obtained coating.
基金the National Science and Technology Support Project of "the Eleventh Five-year Plan"(2006BAE03B06-03)the New Century Talents Support Program of Chinese Education Department (NCET-04-0614)
文摘AB2-type-prepolymerized monomer was rapidly (2 h) prepared at room temperature (25 ℃) using commercially available maleic anhydride (MA) and diethanolamine (DEA) as raw materials. By employing toluene-p-sulfonic acid as a catalyzer, a series of hyperbranched poly(amide-ester) (HBPAE) were successfully synthesized from prepared AB2 monomer by solution condensation polymerization through "one-step process" or "pseudo one-step process" (using pentaerythritol as a center core). The processes were carried out at high temperature of 120 ℃ for 6 h in air atmosphere (inert protection free) with reduced pressure distillation (0.08--0.096 MPa). The results of FT-IR, UV-Vis, TGA, and intrinsic viscosity testing by Ubbelodhe viscometer showed that the prepared HBPAEs possess three-dimensional configuration with unsaturated conjugate structure, large numbers of branches and numerous terminal hydroxyl groups. These result in their low viscosity, high solubility and thermal stability.