CN103241780A - Method for synthesizing carbonyl iron under medium pressure - Google Patents

Abstract

The invention discloses a method for synthesizing carbonyl iron under medium pressure. The method comprises the following preparation steps of: hydrotreating, namely carrying out hydrogenation reduction treatment on sponge iron as a raw material, and removing impurities in the material by using pure hydrogen at 300-500 DEG C, wherein the reaction time is 1-20 hours, and the hydrogen flow rate is 1-100Nm<3>/t; and carbonylating, namely, adding the treated sponge iron to a synthesis kettle to react, sterilizing residues in the kettle by using hot nitrogen replacement after the reaction is ended, feeding exhausted gas to an incinerator to be subjected to burning treatment, simultaneously recovering heat, opening a discharge hole and discharging the residues in the kettle after the nitrogen sterilization is finished, and then entering next circulation. According to the technology for synthesizing carbonyl iron under medium pressure, the requirement on pressure is low and the pressure only needs 7-9MPa, Co in the reaction can be recycled, and therefore the production cost is greatly reduced.

Description

Be pressed into the method for iron carbonyl in a kind of

Technical field

The present invention relates generally to a kind of method of synthesizing carbonyl iron, relates in particular to the method that is pressed into iron carbonyl in a kind of.

Background technology

The synthetic technology of iron carbonyl, each manufacturer adopts the high pressure synthetic route basically both at home and abroad.The ubiquitous shortcoming of domestic each production equipment is: reaction pressure requires high, generally wants more than the 20Mpa, and the CO purity of advancing reactor is not high, and a large amount of CO can not Returning utilization in the reacted gas, CO consumes bigger, causes production cost higher thus, and the off gas treatment amount is big.

Summary of the invention

The object of the invention is exactly in order to remedy the defective of prior art, and the method that is pressed into iron carbonyl in a kind of is provided.

The present invention is achieved by the following technical solutions:

Be pressed into the method for iron carbonyl in a kind of, comprise following preparation process:

(1) hydrotreatment: the raw material sponge iron is handled through hydrogenating reduction earlier, and under 300-500 ℃ of conditions, with the impurity in the purified hydrogen removal material, the reaction times is 1-20h, and the flow of hydrogen is 1-100Nm ³/ t _Material

(2) carbonylation: in be pressed into the iron carbonyl flow process by synthesis reactor, well heater, hotline heater, recycle gas compressor, water recirculator, the refrigerated water water cooler, compositions such as separator, sponge iron behind hydrogenating reduction adds synthesis reactor, after synthesis reactor is built, at first use 5.0MPa(G) nitrogen of pressure sends into and carries out air displacement in the still, check then whether gas leakage is arranged, after inspection finishes with nitrogen purge, not having the CO (carbon monoxide converter) gas of leaking back feeding 7-9MPa (G) hunts leak again, method is the same, fresh carbon monoxide gas is beaten to the carbon monoxide surge tank by the carbon monoxide compressor, carbon monoxide consumption with the postreaction system, the carbon monoxide circulation gas that fresh carbon monoxide gas contains a small amount of iron carbonyl mixes, drive through recycle gas compressor, be introduced into the shell side of input and output material interchanger, with the iron carbonyl that goes out synthesis reactor/CO (carbon monoxide converter) gas heat exchange, again through hotline heater, enter synthesis reactor after being heated to the temperature that needs.Main oxonation is as follows:

Fe＋5CO＝Fe(CO)5?＋240?KJ/mol

Discharge together with a large amount of circulation CO (carbon monoxide converter) gas from the iron carbonyl gas that synthesis reactor produces, tube side through the input and output material interchanger, after the CO (carbon monoxide converter) gas heat exchange of advancing reactor, be cooled to 35-45 ℃, chilled brine water cooler through water recirculator again and be cooled to 4-6 ℃, after as much as possible the carbonyl compound condensation being become liquid state, enter separator, isolated gas phase is the carbon monoxide gas that contains a small amount of iron carbonyl, return the circulation gas surge tank, isolated liquid phase is carbonyl carbonyl iron liquid, uses for subsequent processing;

(3) reaction finishes the interior residue of back still with hot nitrogen displacement sterilization, discharges gas and goes the incinerator burn processing, reclaims heat simultaneously, finishes when the nitrogen sterilization, opens discharge opening, and residue in the discharge still enters next circulation then.

Advantage of the present invention is:

Be pressed into the iron carbonyl technology in the present invention's employing, pressure requires low, only needs 7-9Mpa, and the energy of the CO in reaction Returning utilization, greatly reduces production cost.

Description of drawings

Fig. 1 is process flow sheet of the present invention, wherein: 1, synthesis reactor, 2, well heater, 3, hotline heater, 4, surge tank, 5, water recirculator, 6, the refrigerated water water cooler, 7, recycle gas compressor, 8, separator.

Embodiment

Embodiment 1

Be pressed into the method for iron carbonyl in a kind of, comprise following preparation process:

(1) hydrotreatment: the raw material sponge iron is handled through hydrogenating reduction earlier, and under 400 ℃ of conditions, with the impurity in the purified hydrogen removal material, the reaction times is 10h, and the flow of hydrogen is 50Nm ³/ t _Material

(2) carbonylation: in be pressed into the iron carbonyl flow process by synthesis reactor, well heater, hotline heater, recycle gas compressor, water recirculator, the refrigerated water water cooler, compositions such as separator, sponge iron behind hydrogenating reduction adds synthesis reactor, after synthesis reactor is built, at first use 5.0MPa(G) nitrogen of pressure sends into and carries out air displacement in the still, check then whether gas leakage is arranged, after inspection finishes with nitrogen purge, not having the CO (carbon monoxide converter) gas of leaking back feeding 8MPa (G) hunts leak again, method is the same, fresh carbon monoxide gas is beaten to the carbon monoxide surge tank by the carbon monoxide compressor, carbon monoxide consumption with the postreaction system, the carbon monoxide circulation gas that fresh carbon monoxide gas contains a small amount of iron carbonyl mixes, drive through recycle gas compressor, be introduced into the shell side of input and output material interchanger, with the iron carbonyl that goes out synthesis reactor/CO (carbon monoxide converter) gas heat exchange, again through hotline heater, enter synthesis reactor after being heated to the temperature that needs.Main oxonation is as follows:

Fe＋5CO＝Fe(CO)5?＋240?KJ/mol

Discharge together with a large amount of circulation CO (carbon monoxide converter) gas from the iron carbonyl gas that synthesis reactor produces, tube side through the input and output material interchanger, after the CO (carbon monoxide converter) gas heat exchange of advancing reactor, be cooled to 40 ℃, chilled brine water cooler through water recirculator again and be cooled to 5 ℃, after as much as possible the carbonyl compound condensation being become liquid state, enter separator, isolated gas phase is the carbon monoxide gas that contains a small amount of iron carbonyl, return the circulation gas surge tank, isolated liquid phase is carbonyl carbonyl iron liquid, uses for subsequent processing;

(3) reaction finishes the interior residue of back still with hot nitrogen displacement sterilization, discharges gas and goes the incinerator burn processing, reclaims heat simultaneously, finishes when the nitrogen sterilization, opens discharge opening, and residue in the discharge still enters next circulation then.

Claims (1)

1. be pressed into the method for iron carbonyl in one kind, it is characterized in that comprising following preparation process:

(1) hydrotreatment: the raw material sponge iron is handled through hydrogenating reduction earlier, and under 300-500 ℃ of conditions, with the impurity in the purified hydrogen removal material, the reaction times is 1-20h, and the flow of hydrogen is 1-100Nm ³/ t _Material

(2) carbonylation: the sponge iron that will handle adds synthesis reactor, in synthesis reactor and pure carbon monoxide gas in the reaction through 4-5 days time of 7-9Mpa pressure and 150-300 ℃ of following conditions, main oxonation is: Fe+5CO=Fe (CO) ₅+ 240 KJ/mol;

The iron carbonyl gas that generates is discharged together with a large amount of circulation CO (carbon monoxide converter) gas again and is cooled to 35-45 ℃, chilled brine water cooler through water recirculator and is cooled to 4-6 ℃, as much as possible the carbonyl compound condensation is become liquid state after, enter separator; Isolated gas phase is the carbon monoxide gas that contains a small amount of iron carbonyl, returns the circulation gas surge tank; Isolated liquid phase is carbonyl carbonyl iron liquid, uses for subsequent processing;

(3) reaction finishes the interior residue of back still with hot nitrogen displacement sterilization, discharges gas and goes the incinerator burn processing, reclaims heat simultaneously, finishes when the nitrogen sterilization, opens discharge opening, and residue in the discharge still enters next circulation then.

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