Purification processes are widely used in hydrogen networks of refineries to increase hydrogen reuse. In refineries, hydrogen purification techniques include hydrocarbon, hydrogen sulfide and CO removal units. In addi...Purification processes are widely used in hydrogen networks of refineries to increase hydrogen reuse. In refineries, hydrogen purification techniques include hydrocarbon, hydrogen sulfide and CO removal units. In addition, light hydrocarbon recovery from the hydrogen source streams can also result in hydrogen purification. In order to simplify the superstructure and mathematical model of hydrogen network integration, the models of different purification processes are unified in this paper, including mass balance and the expressions for hydrogen recovery and impurity removal ratios, which are given for all the purification units in refineries. Based on the proposed unified model, a superstructure of hydrogen networks with purification processes is constructed.展开更多
Experiments were conducted for the extraction of phenols from the phenol fraction obtained from the coal tar distillate. The phenol fraction for the present investigation has been procured from Visakhapatnam Steel Pla...Experiments were conducted for the extraction of phenols from the phenol fraction obtained from the coal tar distillate. The phenol fraction for the present investigation has been procured from Visakhapatnam Steel Plant, Visakhapatnam whose composition is known. The phenol fraction from coal tar distillate can be treated for extracting phenols using caustic soda. An attempt has been made to find out whether the existing practice of using only 8%-15% can be modified by increasing the strength of sodium hydroxide and also explore the possibilities of substituting the sodium hydroxide with KOH as an extractant. The different streams of liquids obtained during experimentation have been analyzed by gas chromatograph. Salient features of the study are that higher concentrations of the alkali significantly improved the separation efficiencies of phenols and also regenerate the phenolate with higher phenol content. Increase in the alkali strength has greatly improved the separation as well as the phenol content in the regenerated phenols. Disposal of effluents containing phenols may lead to environmental problem of ground water pollution and the study throws a light on the removal of phenols from the effluents to the extent possible by using higher strength alkali solutions.展开更多
In the IFMIF （International Fusion Materials Irradiation Facility）, high-intensity deuteron ion beam is targeted at flowing liquid Li to produce neutron for long-time irradiation test of fusion materials. Radioactiv...In the IFMIF （International Fusion Materials Irradiation Facility）, high-intensity deuteron ion beam is targeted at flowing liquid Li to produce neutron for long-time irradiation test of fusion materials. Radioactive tritium （T） will be produced as by-product of the D-Li reaction. Y hot trap is expected as an effective system to recover T from the liquid Li target loop. In the present study, absorption behavior of hydrogen isotopes in Y plates is experimentally and analytically investigated under stirring conditions of liquid Li. Experiments clarified that H2 absorption rates of solid Y immersed in Li are independent of the rotating rate in the range of 0 to 100 rpm and are in proportion to the inlet H2 concentration. The rate-determining step is H diffusion in Y. A mass-transfer coefficient is a useful parameter to correlate the overall H transfer from the gaseous phase through liquid Li to the solid Y plate. The effect of activation temperature on the overall performance when Y absorbs H is comparatively investigated. It is considered that heating at 673 K is effective to activate Y along with HF treatment.展开更多
A short and efficient stereoselective synthesis of a styryllactone (-)-isoaltholactone has been achieved in seven steps and 33% overall yield, starting from the readily available carbohydrate D-mannose. The key steps ...A short and efficient stereoselective synthesis of a styryllactone (-)-isoaltholactone has been achieved in seven steps and 33% overall yield, starting from the readily available carbohydrate D-mannose. The key steps of our synthesis involve intramolecular tetrahydrofuran cyclization and one-pot acetonide deprotection-lactonization.展开更多
基金Supported by the National Basic Research Program of China(2012CB720500)the National Natural Science Foundation of China(21276204,20936004)
文摘Purification processes are widely used in hydrogen networks of refineries to increase hydrogen reuse. In refineries, hydrogen purification techniques include hydrocarbon, hydrogen sulfide and CO removal units. In addition, light hydrocarbon recovery from the hydrogen source streams can also result in hydrogen purification. In order to simplify the superstructure and mathematical model of hydrogen network integration, the models of different purification processes are unified in this paper, including mass balance and the expressions for hydrogen recovery and impurity removal ratios, which are given for all the purification units in refineries. Based on the proposed unified model, a superstructure of hydrogen networks with purification processes is constructed.
文摘Experiments were conducted for the extraction of phenols from the phenol fraction obtained from the coal tar distillate. The phenol fraction for the present investigation has been procured from Visakhapatnam Steel Plant, Visakhapatnam whose composition is known. The phenol fraction from coal tar distillate can be treated for extracting phenols using caustic soda. An attempt has been made to find out whether the existing practice of using only 8%-15% can be modified by increasing the strength of sodium hydroxide and also explore the possibilities of substituting the sodium hydroxide with KOH as an extractant. The different streams of liquids obtained during experimentation have been analyzed by gas chromatograph. Salient features of the study are that higher concentrations of the alkali significantly improved the separation efficiencies of phenols and also regenerate the phenolate with higher phenol content. Increase in the alkali strength has greatly improved the separation as well as the phenol content in the regenerated phenols. Disposal of effluents containing phenols may lead to environmental problem of ground water pollution and the study throws a light on the removal of phenols from the effluents to the extent possible by using higher strength alkali solutions.
文摘In the IFMIF （International Fusion Materials Irradiation Facility）, high-intensity deuteron ion beam is targeted at flowing liquid Li to produce neutron for long-time irradiation test of fusion materials. Radioactive tritium （T） will be produced as by-product of the D-Li reaction. Y hot trap is expected as an effective system to recover T from the liquid Li target loop. In the present study, absorption behavior of hydrogen isotopes in Y plates is experimentally and analytically investigated under stirring conditions of liquid Li. Experiments clarified that H2 absorption rates of solid Y immersed in Li are independent of the rotating rate in the range of 0 to 100 rpm and are in proportion to the inlet H2 concentration. The rate-determining step is H diffusion in Y. A mass-transfer coefficient is a useful parameter to correlate the overall H transfer from the gaseous phase through liquid Li to the solid Y plate. The effect of activation temperature on the overall performance when Y absorbs H is comparatively investigated. It is considered that heating at 673 K is effective to activate Y along with HF treatment.
基金supported by the MOST of China (2012ZX09502001-001)the National Natural Science Foundation of China (2012CB822101,21072217 and 21202193)
文摘A short and efficient stereoselective synthesis of a styryllactone (-)-isoaltholactone has been achieved in seven steps and 33% overall yield, starting from the readily available carbohydrate D-mannose. The key steps of our synthesis involve intramolecular tetrahydrofuran cyclization and one-pot acetonide deprotection-lactonization.
