Research and development of green oxidizers and green fuels as a possible replacement for ammonium perchlorate(NH4ClO4,AP) and hydrazine(N2H4) respectively has been increased considerably in the recent years.AP and hy...Research and development of green oxidizers and green fuels as a possible replacement for ammonium perchlorate(NH4ClO4,AP) and hydrazine(N2H4) respectively has been increased considerably in the recent years.AP and hydrazine are the oxidizer and fuel entities,and used in solid and liquid rocket motors respectively.AP is highly toxic and led to adverse health effects,while hydrazine is carcinogenic in nature.AP is in use from the last several decades for rocket and space shuttle propulsion,while hydrazine is used in upper stage liquid propelled rocket motors.It’s a tough task to replace AP with the currently available green oxidizers;since their ballistic properties are weaker when compared to AP and also they can’t be successfully deployed in a solid rocket motor at present Some important available solid green oxidizers are ammonium nitrate(AN),ammonium dinitramide(ADN),hydroxyl ammonium nitrate(HAN),and hydrazinium nitroformate(HNF).However,AN is one of the cheap and readily available oxidizer,and has great potential to use in solid/liquid rocket motors.Tremendous progress has been envisaged till now,and more progress will be there in the coming future over the development of AN based green energetic materials(GEM’s).A concise overview has been presented over the development of phase stabilized ammonium nitrate(PSAN) and AN/KDN based green oxidizers in the present review paper.展开更多
This paper presents the catalytic effects of Cu-Co~* catalyst on the decomposition of AN and AN/KDN based oxidizer and propellant samples. Ozawa-Flynn-Wall(OFW) iso-conversional method was used for the kinetic studies...This paper presents the catalytic effects of Cu-Co~* catalyst on the decomposition of AN and AN/KDN based oxidizer and propellant samples. Ozawa-Flynn-Wall(OFW) iso-conversional method was used for the kinetic studies and to compute the activation energy(Ea) values for various decomposition steps of the prepared oxidizer and propellant samples in the temperature range of 50 e500C. TG-DTG experiments were carried out for both oxidizer and propellant samples at the heating rates of 3, 5, and 10C/min. AN/KDN based oxidizer samples were prepared by an evaporative co-crystallization method. Citric acid sol-gel method was used for the synthesis of Cu-Co~* catalyst. The propellant sample contains HTPB as the fuel binder along with other ingredients such as TDI, DOA, and Glycerol. The Cu-Co~* catalyst was used as 2% by weight to the total weight of catalyzed oxidizer and propellant samples. It was observed from the present study that, Cu-Co~* catalyst helps in reducing the Ea values for AN and AN based propellant samples. However, with the percentage increment of KDN in the AN crystals, Ea value increases.Further, it was observed that Cu-Co~* catalyst stabilizes the initial partial decomposition of KDN.展开更多
The aim of present study is to investigate the burning rate,ignition delay,and flame characteristics of ammonium perchlorate(AP)-hydroxyl terminated poly-butadiene(HTPB)[AP/HTPB]based composite propellants(CSP's)i...The aim of present study is to investigate the burning rate,ignition delay,and flame characteristics of ammonium perchlorate(AP)-hydroxyl terminated poly-butadiene(HTPB)[AP/HTPB]based composite propellants(CSP's)in sub-atmospheric pressure regimes(13 kPae100 kPa).Several fuels and catalyzed were used to evaluate their effects on the combustion characteristics of AP based propellants in sub-atmospheric pressure regimes.In fuels,aluminum(Al)and boron(B)were selected as metallic and non-metallic fuel respectively.While in catalyst,butyl ferrocene(B.F.)and ferric oxide(F.O.)were selected as liquid and solid catalyst respectively.Apart from these,other ingredients that were used are di-octyl adipate(DOA),toluene di-isocyanate(TDI),and glycerol.The article throws some light on the burning rate and ignition delay properties for these new classes of prepared propellant samples.At subatmospheric pressures,all propellants are susceptible to irregular burning with the ejection of soot's,fumes,and unburned particles.F.O.based catalyzed propellants can sustain its combustion up to the lowest pressure.展开更多
文摘Research and development of green oxidizers and green fuels as a possible replacement for ammonium perchlorate(NH4ClO4,AP) and hydrazine(N2H4) respectively has been increased considerably in the recent years.AP and hydrazine are the oxidizer and fuel entities,and used in solid and liquid rocket motors respectively.AP is highly toxic and led to adverse health effects,while hydrazine is carcinogenic in nature.AP is in use from the last several decades for rocket and space shuttle propulsion,while hydrazine is used in upper stage liquid propelled rocket motors.It’s a tough task to replace AP with the currently available green oxidizers;since their ballistic properties are weaker when compared to AP and also they can’t be successfully deployed in a solid rocket motor at present Some important available solid green oxidizers are ammonium nitrate(AN),ammonium dinitramide(ADN),hydroxyl ammonium nitrate(HAN),and hydrazinium nitroformate(HNF).However,AN is one of the cheap and readily available oxidizer,and has great potential to use in solid/liquid rocket motors.Tremendous progress has been envisaged till now,and more progress will be there in the coming future over the development of AN based green energetic materials(GEM’s).A concise overview has been presented over the development of phase stabilized ammonium nitrate(PSAN) and AN/KDN based green oxidizers in the present review paper.
文摘This paper presents the catalytic effects of Cu-Co~* catalyst on the decomposition of AN and AN/KDN based oxidizer and propellant samples. Ozawa-Flynn-Wall(OFW) iso-conversional method was used for the kinetic studies and to compute the activation energy(Ea) values for various decomposition steps of the prepared oxidizer and propellant samples in the temperature range of 50 e500C. TG-DTG experiments were carried out for both oxidizer and propellant samples at the heating rates of 3, 5, and 10C/min. AN/KDN based oxidizer samples were prepared by an evaporative co-crystallization method. Citric acid sol-gel method was used for the synthesis of Cu-Co~* catalyst. The propellant sample contains HTPB as the fuel binder along with other ingredients such as TDI, DOA, and Glycerol. The Cu-Co~* catalyst was used as 2% by weight to the total weight of catalyzed oxidizer and propellant samples. It was observed from the present study that, Cu-Co~* catalyst helps in reducing the Ea values for AN and AN based propellant samples. However, with the percentage increment of KDN in the AN crystals, Ea value increases.Further, it was observed that Cu-Co~* catalyst stabilizes the initial partial decomposition of KDN.
文摘The aim of present study is to investigate the burning rate,ignition delay,and flame characteristics of ammonium perchlorate(AP)-hydroxyl terminated poly-butadiene(HTPB)[AP/HTPB]based composite propellants(CSP's)in sub-atmospheric pressure regimes(13 kPae100 kPa).Several fuels and catalyzed were used to evaluate their effects on the combustion characteristics of AP based propellants in sub-atmospheric pressure regimes.In fuels,aluminum(Al)and boron(B)were selected as metallic and non-metallic fuel respectively.While in catalyst,butyl ferrocene(B.F.)and ferric oxide(F.O.)were selected as liquid and solid catalyst respectively.Apart from these,other ingredients that were used are di-octyl adipate(DOA),toluene di-isocyanate(TDI),and glycerol.The article throws some light on the burning rate and ignition delay properties for these new classes of prepared propellant samples.At subatmospheric pressures,all propellants are susceptible to irregular burning with the ejection of soot's,fumes,and unburned particles.F.O.based catalyzed propellants can sustain its combustion up to the lowest pressure.
