Methyl ethyl ketone oxime, alias butanone oxime, methyl ethyl ketone oxime, colorless oily liquid. Mainly used in alkyd resin coating anti-skinning agent and silicon curing agent, as well as boiler water system deoxidizer.
Preparation or source of methyl ethyl ketone oxime
(1) 2-Nitrobutane catalyzed hydrogenation; this method produces butanone oxime. Since the raw material needs to be obtained by the nitrification reaction, the amount of pollutants such as waste water and waste gas is large, which is not suitable for industrial production;
(2) Electrochemical method; butanone in the presence of aqueous nitrite solution, Zn as an electrode, continuous flow into the CO condition, the current is passed, the current efficiency is only 40%;
(3) hydrazine exchange method; in the presence of an organic acid such as p-toluenesulfonic acid, acetone oxime and butanone react, at 55-60 degrees for 10h, to form acetone and butanone oxime;
(4) Hydration nitrile method; methyl ethyl ketone and hydrazine hydrate. Under the action of alkali as a catalyst, methyl ethyl ketone and hydrazine hydrate become hydrazine, and hydrazine is hydrolyzed under alkaline conditions to obtain hydrazine;
(5) Hydroxylamine method; the method for preparing butanone oxime by reacting hydroxylamine hydrochloride or hydroxylamine sulfate with methyl ethyl ketone is the main route for synthesizing butanone oxime;
(6) Ammoxidation method: generally, TS-1 is used as a catalyst, butanone is used as a raw material, and hydrogen peroxide and ammonia water are added dropwise.
Product performance and use of methyl ethyl ketone oxime
Oxygen removal performance:
Terpenoids are organic compounds with mercapto groups. Currently, the terpene compounds used in boiler deoxidation and shutdown protection are mainly acetaldehyde oxime, dimethyl ketone oxime (acetone oxime) and methyl ethyl ketone oxime. Terpenoids have strong reducibility and are easy to react with oxygen. Terpenoids have good oxygen scavenging properties over a wide range of temperatures and pressures. The most suitable temperature range is 138-336 ° C and the pressure range is 0.3-13.7 MPa. According to the comparative experiment, under the same conditions, the oxygen removal rate and oxygen removal efficiency of the terpenoids were higher than that of hydrazine.
Corrosion inhibition and passivation:
Terpenoids can reduce high-priced iron and copper oxides to low-oxides. The aqueous solution can form a good magnetic oxide film on the surface of the steel, which has good passivation and corrosion inhibition effect on the metal surface. Among them, dimethyl ketoxime has the best effect and requires the least amount of use. According to the comparative experiment, the quinone compound has the same passivation and corrosion inhibition effect as hydrazine, can significantly reduce the iron content in the solution, and has a protective effect on the steel under high temperature and high pressure conditions, wherein dimethyl ketone oxime has the best effect. The amount you need to use is the least. At the same time, terpenoids have a cleaning effect on the corrosion products of copper deposited in pipelines, economizers, etc., which is also the reason why the copper content in the furnace water is significantly increased at the beginning of the use of terpenoids.
The volatility of terpenoids is higher than that of hydrazine, DEHA, morpholine, cyclohexylamine, etc., which is close to the volatility of NH3. The highly volatile oxygen scavenger will have a certain amount of the agent dissolved in the condensed water when the steam is condensed, thereby contributing to the protection of the metal material of the condensed water system.
Through decomposition experiments under high temperature and high pressure conditions, the decomposition products of terpenoids are NH3, N2, H2O, trace acetic acid, and no formic acid production, which has no adverse effect on the water vapor system.
According to the data of LD50, the LD50 of hydrazine is 290mg/kg, the acetaldehyde oxime is 1900mg/kg, the methyl ethyl ketone oxime is 2800mg/kg, the dimethyl ketone oxime is 5500mg/kg, and the toxicity of hydrazine is stronger. The compounds are very toxic and are low in toxic compounds. The skin and mucous membrane contact test by oxygen scavenger showed that the anthraquinone oxygen scavenger had no obvious irritation and damage, while the hydrazine caused skin damage, erosion, mucosal congestion and the like.