Hydrazine vapor

The explosive limits of hydrazine in air are 4.7—100 vol %, the upper limit (100 vol %) indicating that hydrazine vapor is self-explosive. Decomposition can be touched off by catalytic surfaces. The presence of inert gases significantly raises the lower explosive limit (10) (Table 2). 

Hydrazine Diperchlorate (Hydrazinium Diperchlorate in Gmelin it is called Hydrazonium Hydroperchlorate, HDP). N2H4.2HCIO4, mw 232.97, OB +34.3% white crysts, mp 191°, d 2.21 g/cc (Ref 4) CA Registry No 13812-39-0 Preparation. HDP was first prepd by the interaction of equimolar amts of aq Ba perchlorate and hydrazine sulfate, the pptd Ba sulfate filtered off, and the filtrate evapd on a w bath until crystn occurs (Ref 2). It has also been prepd by the interaction of 2 moles of aq perchloric ac and 1 mole of hydrazine hydrate followed by evapn of the w or its azeotropic removal by distn with trichloroethylene (Ref 6), or by sweeping hydrazine vapors into 70% perchloric ac with dry N (Ref 7)... 

The formation of semiconductor nanoparticles and related stmctures exhibiting quantum confinement within LB films has been pmsued vigorously. In 1986, the use of the metal ions in LB films as reactants for the synthesis of nanoscale phases of materials was described [167]. Silver particles, 1-2 mn in size, were produced by the treatment of silver be-henate LB films with hydrazine vapor. The reaction of LB films of metal salts (Cd, Ag, Cu, Zn, Ni, and Pb ) of behenic acid with H2S was mentioned. The use of HCl, HBr, or HI was noted as a route to metal halide particles. In 1988, nanoparticles of CdS in the Q-state size range (below 5 mn) were prepared inside LB films of cadmium arachi-... 

Hydrazine vapor, explosive range of, 73 587 Hydrazine-water azeotrope, breaking, 73 579... 

Jacobson KH et al The toxicology of an aniline-furfuryl alcohol-hydrazine vapor mixture./wi7 flyg Atfoc 7 19 91-100, 1958... 

Comstock CC, Lawson LH, Greene EA, Oberst FW Inhalation toxicity of hydrazine vapor. AMA Arch Ind Hyg Occup Med 10 476 90, 1954... 

In the absence of decomposition catalysts, it has been heated above 500° F with very little decomposition. It is completely insensitive to shock, friction or electrical discharge. Hydrazine vapor has a lower limit of inflammability of 4.67% by volume in air. The upper limit is 100% since the vapor may be exploded without the addition of air (Ref 10)... 

Hydrazine vapor (pure) when sparked at 100° explodes, and a yellow flame accompanies the... 

A beautiful example of vapor-phase intercalation involves the reaction of lead(II) iodide with hydrazine (Ghorayeb et al., 1984). Lead(II) iodide is a layer structure (Cdl2 structure, P3m, no. 164) which forms large yellow transparent hexagonal crystals. When these crystals are exposed to hydrazine vapor, they turn colorless Similar chemistry is observed with ammonia (Cleary, unpublished results). In the ammonia case, when the colorless intercalated crystals are removed from the ammonia atmosphere, the ammonia deintercalates spontaneously and the crystal returns to its yellow color ... 

The compound has also been obtained by blowing anhydrous hydrazine vapor with a stream of dry nitrogen stepwise into a 5-liter bulb containing an excess of SiH3Br.46 The compound, which is colorless and nonvolatile at -64°, is purified by repeated low-temperature vacuum distillation.9,46 Because the compound may explode if it comes into contact with air, it must be prepared and handled in a Stock-type high-vacuum line. 

Caution A spontaneous reaction may result if mixing is prolonged beyond 1 minute. Rubber gloves should be worn to avoid exposure to hydrazine vapors. 

Hydrazine s odor is ammonia-like or fishy and is detectable by smell at 1-10 ppm. Because hydrazine is a marked corrosive, it can cause chemical burns of the skin. Hydrazine vapors may cause irritation of the mucus membranes of the eyes, nose, throat, and respiratory tract. Inhalation of vapors can produce cough, dyspnea, and pulmonary edema. Eye exposure to vapors or liquid can result in conjunctivitis, corneal damage, and blindness. Other clinical effects include nausea, vomiting, tremors, dizziness, hype-rreflexia, seizures, hypotension, liver necrosis, methemoglobinemia, and hemolysis. The National Institute for Occupational Safety and Health recommends that the level of hydrazine in workplace air not exceed 0.03 parts of compound per million parts of air (0.03 ppm) for a 2 h period. The Occupational Safety and Health Administration (OSHA) limits the amount of hydrazine in workplace air to 1 ppm for an 8 h workday. The Environmental Protection Agency (EPA) requires that spills or accidental releases into the environment of 1 pound or more of hydrazine be reported to the EPA. 

Miyatake, N., M. Kamo, K. Satake, Y. Uchiyama and A. Tsugita. Removal of N-terminal formyl groups and deblocking of pyrrolidone carboxylic acid of proteins with anhydrous hydrazine vapor. Eur. J. Biochem. 212 785-789, 1993. 

It is therefore an object of this invention to provide a safer method for manufacturing hydrazine. It is another object of the invention to provide an economical process for safely producing hydrazine of high concentration without the requirement of reduced pressure during distillation. A further object is to provide an improved economical efficient method for producing substantially anhydrous hydrazine. A still further object is to render hydrazine vapor sufficiently insensitive to electric sparks and the like that mass decomposition thereof is prevented. 

In the absence of the hydrocarbon even a small amount of air in the hydrazine vapor is sufficient at elevated temperature to initiate a violent explosion. Source Olin 1956... 

Many syntheses of (benzo)pyridazines involve the use of hydrazine and its derivatives, and the safe handling and disposal of these materials should be given careful consideration. Hydrazine and its salts are potential carcinogens and many hydrazine derivatives have, or are likely to have, toxic properties and all should be handled with care. In addition, hydrazine can react violently with oxidizing agents and the explosive decomposition of hydrazine vapor in air can be catalyzed by, for instance, rust. 

Hydrazine vapors are highly irritating to the eyes, nose, and throat. Inhalation of its vapors or ingestion of the liquid can cause nausea, vomiting, dizziness, and convulsions. Chronic exposure can cause injury to the lung, liver, and kidney. Skin contact with the liquid may result in severe burns. Contact with the eyes can cause damage to vision. 

The reproducibility of signal intensities and drift times had, before 1990, not been considered widely in reports or journal articles on IMS, possibly since detection limits were the main concern. Consequently, there is only a relatively brief record available in the literature on the repeatability of IMS measurements, which is a key to any quantitative analytical method. The few examples that are available are concerned with short-term repeatability, and the relative standard deviation (RSD) for peak areas in these is between 5% and 25%. In one study with a handheld IMS analyzer, reproducibility was 6 to 21% RSD for 5 to 2,500 ng of dialkylphthalates, as shown in Table 8.2. Measurements of hydrazine vapors at 10 to 200 ppb using the same instrument showed precision of about 3 to 16% RSD for these high-reactive and -adsorptive chanicals. ... 

Characterization of Laser-Treated Surface. When the irradiation of ArF laser to a PTFE film was conducted at fluences of 27 mJ cm"2 pulse with 10 Hz in a hydrazine vapor atmosphere, the PTFE surface became hydrophilic. Water contact angle (CA) was measured as the easiest but sensitive method for characterization of our laser processing. Compared with CA of 130° on PTFE before the irradiation, CA was changed to 25° upon irradiation of 3000 pulses at 27 mJ cm 2 pulse" (Table I). 

Table I Atomic ratio of carbon(C) fluorine(F) nitrogen(N) oxygen(O) and contact angle of water on the PTFE surface after ArF laser treatment in hydrazine vapor (Adapted from ref. 19).

Sastry and coworkers [426] have made use of aqueous foams as templates to form platelets and particles of Au. A foam is generated in a column by the use of the surfactant CTAB (cetylthimethylammonium bromide) com-plexed with HAUCI4. The Au ions dispersed over the foam are reduced by a gaseous reductant such as hydrazine vapors. It is supposed that the platelets are produced by reduction of the CTAB-Au complex molecules at the bubble walls, while the same complex molecules at the interbubble voids provide the isotropic space required for the generation of spherical particles. 

Vaghjiani GL. Laser photolysis studies of hydrazine vapor 193 and 222-nm H-atom primary quantum yields at 296 K, and the kinetics of H + reaction over the temperature range 222-657 K. Int J Chem Kinet. 1995 27 777-90. 

Wang Zhijuan, Wu Shixin, Zhang Juan, et al. Comparative studies on single-layer reduced graphene oxide films obtained by electrochemical reduction and hydrazine vapor reduction. Nanoscale Res. Lett. 1 no. 1 (2012) 161-167. 

Steinbach F, Zobel M (1973) Catalytic decomposition of hydrazine vapor on monomeric p-copper phthalocyanine. Z Phys Chem 87 142-150... 

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