An air superoleophobic/superhydrophilic composite coating with a unique structure was fabricated by oxidation and further modification of the copper mesh,and its design principle was clarified.This unique bird-nest-li...An air superoleophobic/superhydrophilic composite coating with a unique structure was fabricated by oxidation and further modification of the copper mesh,and its design principle was clarified.This unique bird-nest-like configuration gives it instant superhydrophilicity due to the high surface roughness and high polar surface free energy components,while air superoleophobicity is caused by its extremely low dispersive surface free energy components.Furthermore,a water-resistance mechanism was proposed whereby a polyelectrolyte plays a critical role in improving the water-resistance of fluorosurfactants.It can separate oil–water mixtures with high efficiency(98.72%)and high flux(25185 L·m−2·h−1),and can be reused.In addition,our composite coating had certain anti-acid,anti-alkali,anti-salt and anti-sand impact performance.More importantly,after being soaked in water for a long time or being exposed to the air for a long time,it still retained ultra-high air oil contact angle and showed excellent stability,which provided the possibility for practical applications.Thus,these findings offer the potential for significant practical applications in managing oily wastewater and marine oil spill incidents.展开更多
Biochars produced from crab shell(CSB),oak sawdust(OB),Jeru salem artichoke tuber(JAB) and sorghum grain(SB) displayed distinguishable adsorption-related characteristics,such as specific surface area(SSA),ash content ...Biochars produced from crab shell(CSB),oak sawdust(OB),Jeru salem artichoke tuber(JAB) and sorghum grain(SB) displayed distinguishable adsorption-related characteristics,such as specific surface area(SSA),ash content and acidic oxygen-containing functional groups(AFGs),which linked to the biochar adsorption mechanisms of most pollutants.Herein,PO4^3-,Cd^2+,and nitrobenzene(NB) were employed for adsorption by these biochars to elucidate the dominant factors for the adsorption.Adsorption performance of the three pollutants onto these four biochars varied considerably,as exemplified by the excellent adsorption of PO4^3- and Cd^2+ onto CSB(225.3 and 116.0 mg/g,respectively) as compared with onto the other three biochars(4.2-37.1 mg/g for P043-and 9.7-41.0 mg/g for Cd^2+).OB displayed the best adsorption of NB(72.0 mg/g),followed by SB(39.5 mg/g),JAB(31.1 mg/g),and CSB(23.6 mg/g).The kinetics and isotherm adsorption assessments couple with material characterization suggested that the sorption of selected pollutants on biochars was attributed to the multiple mechanisms involved,including coprecipitation,chemical bonds,cation exchange,physical absorption,and complexation.Further path analysis suggested that AFGs and ash content in biochars were more important than SSA with regards to pollutant removal,especially,with ash playing a crucial role in the removal of Cd2+ and PO43-,and AFGs being mainly re s ponsible for NB adsorption.These findings might offer guidance on the preparation or modification of biochar with a targeted function for pollutant removal through an understanding the dominant factors.展开更多
基金supported by the Science and Technology Department of Sichuan Province(2021YFG0275).
文摘An air superoleophobic/superhydrophilic composite coating with a unique structure was fabricated by oxidation and further modification of the copper mesh,and its design principle was clarified.This unique bird-nest-like configuration gives it instant superhydrophilicity due to the high surface roughness and high polar surface free energy components,while air superoleophobicity is caused by its extremely low dispersive surface free energy components.Furthermore,a water-resistance mechanism was proposed whereby a polyelectrolyte plays a critical role in improving the water-resistance of fluorosurfactants.It can separate oil–water mixtures with high efficiency(98.72%)and high flux(25185 L·m−2·h−1),and can be reused.In addition,our composite coating had certain anti-acid,anti-alkali,anti-salt and anti-sand impact performance.More importantly,after being soaked in water for a long time or being exposed to the air for a long time,it still retained ultra-high air oil contact angle and showed excellent stability,which provided the possibility for practical applications.Thus,these findings offer the potential for significant practical applications in managing oily wastewater and marine oil spill incidents.
基金supported by the Department of Science and Technology of Sichuan Province (Nos.2017SZ0028,2017HH0047)
文摘Biochars produced from crab shell(CSB),oak sawdust(OB),Jeru salem artichoke tuber(JAB) and sorghum grain(SB) displayed distinguishable adsorption-related characteristics,such as specific surface area(SSA),ash content and acidic oxygen-containing functional groups(AFGs),which linked to the biochar adsorption mechanisms of most pollutants.Herein,PO4^3-,Cd^2+,and nitrobenzene(NB) were employed for adsorption by these biochars to elucidate the dominant factors for the adsorption.Adsorption performance of the three pollutants onto these four biochars varied considerably,as exemplified by the excellent adsorption of PO4^3- and Cd^2+ onto CSB(225.3 and 116.0 mg/g,respectively) as compared with onto the other three biochars(4.2-37.1 mg/g for P043-and 9.7-41.0 mg/g for Cd^2+).OB displayed the best adsorption of NB(72.0 mg/g),followed by SB(39.5 mg/g),JAB(31.1 mg/g),and CSB(23.6 mg/g).The kinetics and isotherm adsorption assessments couple with material characterization suggested that the sorption of selected pollutants on biochars was attributed to the multiple mechanisms involved,including coprecipitation,chemical bonds,cation exchange,physical absorption,and complexation.Further path analysis suggested that AFGs and ash content in biochars were more important than SSA with regards to pollutant removal,especially,with ash playing a crucial role in the removal of Cd2+ and PO43-,and AFGs being mainly re s ponsible for NB adsorption.These findings might offer guidance on the preparation or modification of biochar with a targeted function for pollutant removal through an understanding the dominant factors.
