Magnesium(Mg)is a widely used and attractive metal,known for its unique physical and chemical properties,and it has been employed in the manufacture of many practical materials.Layered Double Hydroxides(LDHs),particul...Magnesium(Mg)is a widely used and attractive metal,known for its unique physical and chemical properties,and it has been employed in the manufacture of many practical materials.Layered Double Hydroxides(LDHs),particularly Mg-based LDHs,rank among the most prevalent two-dimensional materials utilized in separation processes,which include adsorption,extraction,and membrane technology.The high popularity of Mg-based LDHs in separation applications can be attributed to their properties,such as excellent hydrophilicity,high surface area,ion exchangeability,and adjustable interlayer space.Currently,polymer membranes play a pivotal role in semi-industrial and industrial separation processes.Consequently,the development of polymer membranes and the mitigation of their limitations have emerged as compelling topics for researchers.Several methods exist to enhance the separation performance and anti-fouling properties of polymer membranes.Among these,incorporating additives into the membrane polymer matrix stands out as a cost-effective,straightforward,readily available,and efficient approach.The use of Mg-based LDHs,either in combination with other materials or as a standalone additive in the polymer membrane matrix,represents a promising strategy to bolster the separation and anti-fouling efficacy of flat sheet mixed matrix polymer membranes.This review highlights Mg-based LDHs as high-potential additives designed to refine flat sheet mixed matrix polymer membranes for applications in wastewater treatment and brackish water desalination.展开更多
为研究表面有机化层状双羟基复合金属氢氧化物(LDHs)对表面有机化LDHs/橡胶粉复合改性沥青高温性能的影响,文章对基质沥青、橡胶粉改性沥青和表面有机化LDHs/橡胶粉复合改性沥青进行针入度、软化点、延度三大指标与动态剪切流变试验(Dyn...为研究表面有机化层状双羟基复合金属氢氧化物(LDHs)对表面有机化LDHs/橡胶粉复合改性沥青高温性能的影响,文章对基质沥青、橡胶粉改性沥青和表面有机化LDHs/橡胶粉复合改性沥青进行针入度、软化点、延度三大指标与动态剪切流变试验(Dynamic Shear Rheological Test, DSR)和高温力学性能测试。结果表明:加入表面有机化LDHs后,增加了橡胶粉改性沥青的针入度,并提高橡胶粉改性沥青的软化点和延度;在DSR试验中,同一温度条件下,表面有机化LDHs/橡胶粉复合改性沥青的车辙因子显著高于基质沥青和橡胶粉改性沥青。故通过掺加表面有机化LDHs和橡胶粉来提高沥青的耐高温性能具有可行性。In order to study the effect of surface organic Layered Double Hydroxides (LDHs)on the high temperature performance of surface organic LDHs/rubber powder composite modified asphalt, the three indexes of penetration, softening point and ductility of matrix asphalt, rubber powder modified asphalt and surface organic LDHs/rubber powder composite modified asphalt, Dynamic Shear Rheological Test (DSR)and high temperature mechanical properties test were carried out in this paper. The results show that the addition of surface organic LDHs increases the penetration of rubber powder-modified asphalt and improves the softening point and ductility of rubber powder-modified asphalt. In the DSR test, under the same temperature conditions, the rutting factor of the surface organic LDHs/rubber powder composite modified asphalt is significantly higher than that of the matrix asphalt and rubber powder modified asphalt. Therefore, it is feasible to improve the high temperature resistance of asphalt by adding surface organic LDHs and rubber powder.展开更多
Ni-Al-CO3 LDHs/γ-Al2O3 have been prepared using an in-situ synthesis technique. NH3·H2O was chosen as activation agent of Al on the γ-Al2O3 surface as well as precipitant. Ni-Al-CO3 LDHs/γ-Al2O3 was synthesize...Ni-Al-CO3 LDHs/γ-Al2O3 have been prepared using an in-situ synthesis technique. NH3·H2O was chosen as activation agent of Al on the γ-Al2O3 surface as well as precipitant. Ni-Al-CO3 LDHs/γ-Al2O3 was synthesized by controlling the reaction conditions such as temperature, concentration of Ni2+ and initial pH. The crystalline structure, chemical composition and porous structure were characterized by means of XRD, FT-IR, TG-DTA, 27Al MAS-NMR and N2 adsorption-desorption. The resulting sample of Ni-Al-CO3 LDHs/γ-Al2O3 possesses higher specific area and narrower pore distribution, in which Ni-Al-CO3 LDHs are located on the surface of γ-Al2O3 and share the same Al-O bonds with the γ-Al2O3 lattice. Finally a possible structural model was proposed to account for the porous characters of Ni-Al-CO3 LDHs/γ-Al2O3.展开更多
文摘Magnesium(Mg)is a widely used and attractive metal,known for its unique physical and chemical properties,and it has been employed in the manufacture of many practical materials.Layered Double Hydroxides(LDHs),particularly Mg-based LDHs,rank among the most prevalent two-dimensional materials utilized in separation processes,which include adsorption,extraction,and membrane technology.The high popularity of Mg-based LDHs in separation applications can be attributed to their properties,such as excellent hydrophilicity,high surface area,ion exchangeability,and adjustable interlayer space.Currently,polymer membranes play a pivotal role in semi-industrial and industrial separation processes.Consequently,the development of polymer membranes and the mitigation of their limitations have emerged as compelling topics for researchers.Several methods exist to enhance the separation performance and anti-fouling properties of polymer membranes.Among these,incorporating additives into the membrane polymer matrix stands out as a cost-effective,straightforward,readily available,and efficient approach.The use of Mg-based LDHs,either in combination with other materials or as a standalone additive in the polymer membrane matrix,represents a promising strategy to bolster the separation and anti-fouling efficacy of flat sheet mixed matrix polymer membranes.This review highlights Mg-based LDHs as high-potential additives designed to refine flat sheet mixed matrix polymer membranes for applications in wastewater treatment and brackish water desalination.
文摘为研究表面有机化层状双羟基复合金属氢氧化物(LDHs)对表面有机化LDHs/橡胶粉复合改性沥青高温性能的影响,文章对基质沥青、橡胶粉改性沥青和表面有机化LDHs/橡胶粉复合改性沥青进行针入度、软化点、延度三大指标与动态剪切流变试验(Dynamic Shear Rheological Test, DSR)和高温力学性能测试。结果表明:加入表面有机化LDHs后,增加了橡胶粉改性沥青的针入度,并提高橡胶粉改性沥青的软化点和延度;在DSR试验中,同一温度条件下,表面有机化LDHs/橡胶粉复合改性沥青的车辙因子显著高于基质沥青和橡胶粉改性沥青。故通过掺加表面有机化LDHs和橡胶粉来提高沥青的耐高温性能具有可行性。In order to study the effect of surface organic Layered Double Hydroxides (LDHs)on the high temperature performance of surface organic LDHs/rubber powder composite modified asphalt, the three indexes of penetration, softening point and ductility of matrix asphalt, rubber powder modified asphalt and surface organic LDHs/rubber powder composite modified asphalt, Dynamic Shear Rheological Test (DSR)and high temperature mechanical properties test were carried out in this paper. The results show that the addition of surface organic LDHs increases the penetration of rubber powder-modified asphalt and improves the softening point and ductility of rubber powder-modified asphalt. In the DSR test, under the same temperature conditions, the rutting factor of the surface organic LDHs/rubber powder composite modified asphalt is significantly higher than that of the matrix asphalt and rubber powder modified asphalt. Therefore, it is feasible to improve the high temperature resistance of asphalt by adding surface organic LDHs and rubber powder.
文摘Ni-Al-CO3 LDHs/γ-Al2O3 have been prepared using an in-situ synthesis technique. NH3·H2O was chosen as activation agent of Al on the γ-Al2O3 surface as well as precipitant. Ni-Al-CO3 LDHs/γ-Al2O3 was synthesized by controlling the reaction conditions such as temperature, concentration of Ni2+ and initial pH. The crystalline structure, chemical composition and porous structure were characterized by means of XRD, FT-IR, TG-DTA, 27Al MAS-NMR and N2 adsorption-desorption. The resulting sample of Ni-Al-CO3 LDHs/γ-Al2O3 possesses higher specific area and narrower pore distribution, in which Ni-Al-CO3 LDHs are located on the surface of γ-Al2O3 and share the same Al-O bonds with the γ-Al2O3 lattice. Finally a possible structural model was proposed to account for the porous characters of Ni-Al-CO3 LDHs/γ-Al2O3.
