Thermal catalytic degradation of organic pollutants conducted in the dark at room temperature under atmospheric pressure without the need of external chemicals and energy sources has attracted a lot of attention over ...Thermal catalytic degradation of organic pollutants conducted in the dark at room temperature under atmospheric pressure without the need of external chemicals and energy sources has attracted a lot of attention over the last two decades. It provides unparalleled advantages over other advanced oxidation processes (AOPs) in treating domestic and industrial contaminated wastewater from the viewpoint of energy/chemical conservation and ease of operation. Rich knowledge has been accumulated in terms of the synthesis and application of thermal catalysts though controversies remain regarding their underlying mechanisms. This review sheds light on the proposed thermo- catalysis mechanism for the first time and presents the development of thermal catalysts under dark ambient conditions with a focus on catalyst materials, catalytic activity, and mechanism. The present review aims to provide mechanistic insights into the rational design of novel and efficient catalysts, and their underlying mechanisms as well as the emerging challenges and perspectives in thermo-catalysis under dark ambient conditions used for the practical and efficient treatment of contaminated wastewater.展开更多
High temperature treatment of tungsten alloy of W-5wt.% TM （transition metals, TM = Ni, Fe, Cu, Co） nanopowder was run under different temperatures to cover the oxidation rate at different temperatures. The correlat...High temperature treatment of tungsten alloy of W-5wt.% TM （transition metals, TM = Ni, Fe, Cu, Co） nanopowder was run under different temperatures to cover the oxidation rate at different temperatures. The correlation was developed for certain temperatures to find an equation for the relation between time and weight. The thermal treatment was done for different quantities at certain times. The proposed equation studies the correlation between temperature, time, and weight. For each temperature, a number of points were recorded from the measured oxidation curve. The shape of the curves is well-represented in this paper. The final results will present the highest temperature, the maximum weight, and the maximum time for full oxidation at high and low temperatures.展开更多
For the last two decades polymeric membranes have been used in several gas separation processes. For the high selectivity and permeability various types of membranes have been developed. Thin layers to high dense and ...For the last two decades polymeric membranes have been used in several gas separation processes. For the high selectivity and permeability various types of membranes have been developed. Thin layers to high dense and hollow fiber to asymmetric wounded materials to determine the effective separation of CO2 from CH4 were used. Ideal membrane materials must have provisions of durability, chemical and thermal resistance, effective separation and economical production and operation. In this review it is observed that most of the polymeric materials face plasticization problem in the separation of CO2 from CH4. This is due to the condensable nature of carbon dioxide that causes swelling in most of the polymeric membranes due to which the efficiency of selectivity and permeability is affected. Most extensive works have been carried out in developing the chemical structure and compositions of polymeric materials to improve the separation properties. Cross-linking and blending of molecular sieving called ＂mixed-matrix＂ are the most useful approaches applied in this regard, but no where it is found to be fully effective and ideal polymeric membranes commercially fit to replace the existing systems of CO2 separation from the natural gas. Still area is open to work on to produce more worth full materials and switch towards liquid membranes and hybrid systems.展开更多
基金funding support by the National Natural Science Foundation of China (51674091, 51104048)~~
文摘Thermal catalytic degradation of organic pollutants conducted in the dark at room temperature under atmospheric pressure without the need of external chemicals and energy sources has attracted a lot of attention over the last two decades. It provides unparalleled advantages over other advanced oxidation processes (AOPs) in treating domestic and industrial contaminated wastewater from the viewpoint of energy/chemical conservation and ease of operation. Rich knowledge has been accumulated in terms of the synthesis and application of thermal catalysts though controversies remain regarding their underlying mechanisms. This review sheds light on the proposed thermo- catalysis mechanism for the first time and presents the development of thermal catalysts under dark ambient conditions with a focus on catalyst materials, catalytic activity, and mechanism. The present review aims to provide mechanistic insights into the rational design of novel and efficient catalysts, and their underlying mechanisms as well as the emerging challenges and perspectives in thermo-catalysis under dark ambient conditions used for the practical and efficient treatment of contaminated wastewater.
文摘High temperature treatment of tungsten alloy of W-5wt.% TM （transition metals, TM = Ni, Fe, Cu, Co） nanopowder was run under different temperatures to cover the oxidation rate at different temperatures. The correlation was developed for certain temperatures to find an equation for the relation between time and weight. The thermal treatment was done for different quantities at certain times. The proposed equation studies the correlation between temperature, time, and weight. For each temperature, a number of points were recorded from the measured oxidation curve. The shape of the curves is well-represented in this paper. The final results will present the highest temperature, the maximum weight, and the maximum time for full oxidation at high and low temperatures.
文摘For the last two decades polymeric membranes have been used in several gas separation processes. For the high selectivity and permeability various types of membranes have been developed. Thin layers to high dense and hollow fiber to asymmetric wounded materials to determine the effective separation of CO2 from CH4 were used. Ideal membrane materials must have provisions of durability, chemical and thermal resistance, effective separation and economical production and operation. In this review it is observed that most of the polymeric materials face plasticization problem in the separation of CO2 from CH4. This is due to the condensable nature of carbon dioxide that causes swelling in most of the polymeric membranes due to which the efficiency of selectivity and permeability is affected. Most extensive works have been carried out in developing the chemical structure and compositions of polymeric materials to improve the separation properties. Cross-linking and blending of molecular sieving called ＂mixed-matrix＂ are the most useful approaches applied in this regard, but no where it is found to be fully effective and ideal polymeric membranes commercially fit to replace the existing systems of CO2 separation from the natural gas. Still area is open to work on to produce more worth full materials and switch towards liquid membranes and hybrid systems.
