The coagulation process is a widely applied technology in water and wastewater treatment.Novel composite polyferric mag-nesium-silicate-sulfate(PFMS)coagulants were synthesized using Na_(2)SiO_(3)·9H_(2)O,Fe_(2)(...The coagulation process is a widely applied technology in water and wastewater treatment.Novel composite polyferric mag-nesium-silicate-sulfate(PFMS)coagulants were synthesized using Na_(2)SiO_(3)·9H_(2)O,Fe_(2)(SO_(4))_(3),and MgSO_(4) as raw materials in this paper.The effects of aging time,Fe:Si:Mg,and OH:M molar ratios(M represents the metal ions)on the coagulation performance of the as-pre-pared PFMS were systematically investigated to obtain optimum coagulants.The results showed that PFMS coagulant exhibited good co-agulation properties in the treatment of simulated humic acid-kaolin surface water and reactive dye wastewater.When the molar ratio was controlled at Fe:Si:Mg=2:2:1 and OH:M=0.32,the obtained PFMS presented excellent stability and a high coagulation efficiency.The removal efficiency of ultraviolet UV254 was 99.81%,and the residual turbidity of the surface water reached 0.56 NTU at a dosage of 30 mg·L^(-1).After standing the coagulant for 120 d in the laboratory,the removal efficiency of UV254 and residual turbidity of the surface wa-ter were 88.12%and 0.68 NTU,respectively,which accord with the surface water treatment requirements.In addition,the coagulation performance in the treatment of reactive dye wastewater was greatly improved by combining the advantages of magnesium and iron salts.Compared with polyferric silicate-sulfate(PFS)and polymagnesium silicate-sulfate(PMS),the PFMS coagulant played a better decolor-ization role within the pH range of 7-13.展开更多
The disinfection of drinking water was an outstanding(and perhaps the most important)public health achievement of the 20^(th) century.According to the United Nations World Health Organization,
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
<i>Entamoeba histolytica</i> is an anaerobic parasitic protozoan and well known as a human pathogen, while its close relative, <i>Entamoeba dispar</i>, also possesses similar characteristics as...<i>Entamoeba histolytica</i> is an anaerobic parasitic protozoan and well known as a human pathogen, while its close relative, <i>Entamoeba dispar</i>, also possesses similar characteristics as an infectious agent. These microorganisms are generally transmitted in fecal-contaminated water. However, <i>E. dispar</i> present in industrial wastewater is also capable of creating biofilms that can cause adverse impacts in piping networks. Therefore, it is important to detect both of these protozoan species in water and to find a cost-effective technique for inactivation or management control. This review article summarizes the available detection methods in water and wastewater matrices along with feasible disinfection techniques.展开更多
Hydrogels have various potential applications due to their unique characteristics and recently,hydrogels have been utilized as adsorbents in wastewater treatment because of their ability to remove contaminants from wa...Hydrogels have various potential applications due to their unique characteristics and recently,hydrogels have been utilized as adsorbents in wastewater treatment because of their ability to remove contaminants from water.Constructing strong hydrogels with high adsorption capabilities is crucial for effective wastewater treatment.Scientists and researchers are working to improve the properties of hydrogels by incorporating inorganic elements into polymer networks,which further reduces the costs as well as simplifies their preparation.Natural polymers like starch and alginate are widespread due to their economic and biological advantages,such as biodegradability,biocompatibility,reduced toxicity,environmental friendliness,and low cost.The adsorption of pollutants onto hydrogels as well as their use as antimicrobial agents has garnered significant attention.This review paper summarizes the latest studies on using hydrogels as adsorbents to remove endocrine-disrupting chemicals(EDCs),persistent organic pollutants(POPs),and other emerging pollutants from water environments along with their use as antimicrobial agents.In the first step,different classes of hydrogels and different characterization techniques have been discussed.Next antimicrobial potential of hydrogels is elaborated to understand how these hydrogels can be a potential candidate for such activities.While discussing the adsorption application of hydrogels,different isothermal,kinetics and thermodynamics models have been discussed to highlight the mechanism and nature of forces involved in adsorption of pollutants.Further different simulations such as DFT and MD have been discussed to get more holistic understanding of pollutants adsorption onto hydrogels.A limited number of studies have utilized other techniques such as Monte Carlo simulations and computational fluid dynamics(CFD)so it is important to explore a variety of computational methods to gain a comprehensive understanding of the adsorption process onto hydrogels.展开更多
基金supported by the National Natural Science Foundation of China (No.U1810205).
文摘The coagulation process is a widely applied technology in water and wastewater treatment.Novel composite polyferric mag-nesium-silicate-sulfate(PFMS)coagulants were synthesized using Na_(2)SiO_(3)·9H_(2)O,Fe_(2)(SO_(4))_(3),and MgSO_(4) as raw materials in this paper.The effects of aging time,Fe:Si:Mg,and OH:M molar ratios(M represents the metal ions)on the coagulation performance of the as-pre-pared PFMS were systematically investigated to obtain optimum coagulants.The results showed that PFMS coagulant exhibited good co-agulation properties in the treatment of simulated humic acid-kaolin surface water and reactive dye wastewater.When the molar ratio was controlled at Fe:Si:Mg=2:2:1 and OH:M=0.32,the obtained PFMS presented excellent stability and a high coagulation efficiency.The removal efficiency of ultraviolet UV254 was 99.81%,and the residual turbidity of the surface water reached 0.56 NTU at a dosage of 30 mg·L^(-1).After standing the coagulant for 120 d in the laboratory,the removal efficiency of UV254 and residual turbidity of the surface wa-ter were 88.12%and 0.68 NTU,respectively,which accord with the surface water treatment requirements.In addition,the coagulation performance in the treatment of reactive dye wastewater was greatly improved by combining the advantages of magnesium and iron salts.Compared with polyferric silicate-sulfate(PFS)and polymagnesium silicate-sulfate(PMS),the PFMS coagulant played a better decolor-ization role within the pH range of 7-13.
文摘The disinfection of drinking water was an outstanding(and perhaps the most important)public health achievement of the 20^(th) century.According to the United Nations World Health Organization,
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<i>Entamoeba histolytica</i> is an anaerobic parasitic protozoan and well known as a human pathogen, while its close relative, <i>Entamoeba dispar</i>, also possesses similar characteristics as an infectious agent. These microorganisms are generally transmitted in fecal-contaminated water. However, <i>E. dispar</i> present in industrial wastewater is also capable of creating biofilms that can cause adverse impacts in piping networks. Therefore, it is important to detect both of these protozoan species in water and to find a cost-effective technique for inactivation or management control. This review article summarizes the available detection methods in water and wastewater matrices along with feasible disinfection techniques.
文摘Hydrogels have various potential applications due to their unique characteristics and recently,hydrogels have been utilized as adsorbents in wastewater treatment because of their ability to remove contaminants from water.Constructing strong hydrogels with high adsorption capabilities is crucial for effective wastewater treatment.Scientists and researchers are working to improve the properties of hydrogels by incorporating inorganic elements into polymer networks,which further reduces the costs as well as simplifies their preparation.Natural polymers like starch and alginate are widespread due to their economic and biological advantages,such as biodegradability,biocompatibility,reduced toxicity,environmental friendliness,and low cost.The adsorption of pollutants onto hydrogels as well as their use as antimicrobial agents has garnered significant attention.This review paper summarizes the latest studies on using hydrogels as adsorbents to remove endocrine-disrupting chemicals(EDCs),persistent organic pollutants(POPs),and other emerging pollutants from water environments along with their use as antimicrobial agents.In the first step,different classes of hydrogels and different characterization techniques have been discussed.Next antimicrobial potential of hydrogels is elaborated to understand how these hydrogels can be a potential candidate for such activities.While discussing the adsorption application of hydrogels,different isothermal,kinetics and thermodynamics models have been discussed to highlight the mechanism and nature of forces involved in adsorption of pollutants.Further different simulations such as DFT and MD have been discussed to get more holistic understanding of pollutants adsorption onto hydrogels.A limited number of studies have utilized other techniques such as Monte Carlo simulations and computational fluid dynamics(CFD)so it is important to explore a variety of computational methods to gain a comprehensive understanding of the adsorption process onto hydrogels.