CN101439846A

CN101439846A - Novel process for producing fluorine hydride by batch process

Info

Publication number: CN101439846A
Application number: CNA2007100098442A
Authority: CN
Inventors: 旷戈
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-11-19
Filing date: 2007-11-19
Publication date: 2009-05-27

Abstract

The invention provides an intermittent production process for hydrogen fluoride, which has the characteristics of reducing energy consumption, raw material consumption and equipment investment, improving the production efficiency of a reactor, and eliminating the hidden trouble of environmental pollution relative to a continuous production process of a rotary kiln. The process comprises the following steps: (1) a reaction that acid-grade fluorspar powder and sulfuric acid generate HF is intermittently performed in a jacket reactor with stirring and conduction oil or molten salt heating according to the proportion metered by the chemical reaction; (2) the fluorspar powder is heated to be between 200 and 400 DEG C inside or outside the reactor and enters the reactor first, the sulfuric acid is heated to be between 100 and 280 DEG C and then is gradually added into the reactor to react with the fluorspar powder, the stirring is performed, the heat in the reactor is provided by the conduction oil or the molten salt through a jacket of the reactor, and produced HF gas is purified and then is condensed and rectified to produce AHF, and produces hydrofluoric acid by water absorption or directly produces a downstream product; and (3) after the reaction is finished, gypsum residue is cooled to a temperature lower than 100 DEG C by the conduction oil of the jacket in the reactor and then is discharged, or is cooled outside the reactor, thus a production period is finished.

Description

A kind of novel process of producing fluorine hydride by batch process

Technical field

Anhydrous hydrofluoric acid (AHF) and hydrofluoric acid are used as the fluorizating agent in displacement and the addition reaction in organic and inorganic chemistry.The maximum purposes of anhydrous hydrofluoric acid and hydrofluoric acid is a fluorocarbon, accounts for 45% of worldwide production HF greatly, and about 30% is used to produce AlF ₃, remaining 30% Chemical Manufacture that is used for other.

Anhydrous hydrogen fluoride for industrial use and Acid of Hydrofluoric Acid Production all adopt acid level fluorite powder (CaF in the world at present ₂) with the various forms of rotary kiln continuous production processes of vitriolic reaction.

The chemical reaction of anhydrous hydrofluoric acid

The principal reaction that anhydrous hydrofluoric acid is produced can be expressed as:

CaF ₂(s)+H ₂SO ₄(l)→2HF(g)+CaSO ₄(s)

This reaction is thermo-negative reaction.Except that principal reaction, because CaF ₂Contain impurity, also have some less important reactions:

SiO ₂+4HF→SiF ₄+2H ₂O

CaCO ₃+H ₂SO ₄→CaSO ₄+CO ₂+H ₂O

Me2O3+3H ₂SO4→Me ₂(SO ₄) ₃+3H ₂O (Me＝Fe，Al)

MS+H ₂SO ₄→MSO ₄+H ₂S (Me＝Pb，Zn，Fe，As)

Fe (reactor)+2H ₂SO ₄→ FeSO ₄+ SO ₂+ H ₂O

SO ₂+2H ₂S→3S+H ₂O

H ₂SO ₄+H ₂S→S+SO ₂+2H ₂O

The gas that these generated is such as SiF ₄, CO ₂And SO ₂Deng so-called " lower boiling " product and such as H ₂SO ₄, H ₂O, HSO ₃F, AsF ₃And H ₃PO ₄Gas etc. " high boiling point " product by distillation, separates from anhydrous hydrofluoric acid; Or entered in the water hydrofluoric acid product by the water absorption portion.

Summary of the invention

The purpose of this invention is to provide the hydrofluoric brand-new batch production technology of a kind of production,, have the energy consumption that reduces production process relatively with present rotary kiln continuous production processes; Reduce the consumption of raw materials for production; Reduce investment in production equipment, improve the production efficiency of reactor, the advantage of the environmental pollution hidden danger of elimination production process etc.

In order to achieve the above object, this technology comprises:

(1) acid level fluorite powder and sulfuric acid jacketed reactor discontinuous that stir at band in the ratio of chemical reaction metering, that heat by chuck thermal oil or fused salt is carried out.

(2) acid level fluorite powder and sulfuric acid measure outside reactor in the ratio of chemical reaction metering, the acid level fluorite powder that measures in reactor or outside be heated to 200-400 ℃ and be introduced into reactor, progressively join after the sulfuric acid that measures is heated to 100-280 ℃ in the reactor and react with acid level fluorite powder, and stir, reaction process is thermo-negative reaction, reactor temperature is by the outer chuck of reactor, provide heat by thermal oil or fused salt, the HF gas that reaction produces is through after purifying, a kind of mode is: condensation is got off, after the process rectifying separation goes out high lower-boiling impurity, produce the anhydrous hydrogen fluoride (AHF) that meets various requirement; The second way: directly absorbing production by water has water hydrofluoric acid; The third mode: the derived product that directly is used for producing HF.

(3) after reaction was finished, the gypsum tailings of generation thermal oil by chuck in reactor was cooled to the discharge of back below 100 ℃ reactor, or cools off gypsum tailings outside after discharging reactor; Finish the cycle of a reaction process.

Relative and the present various rotary kiln technologies of the present invention are a kind of revolutionary changes, have following beneficial effect:

1. this process process equipment is simple, and is convenient easy to operate, the rotary system of existing rotary kiln technology, and equipment such as hot air circulating system, coal gas system, dreg removing system are huge, complexity, the control difficulty is invested huge.

2. this technological process is periodical operation, and raw material fluorite and sulfuric acid can have the sufficient time complete reaction, and prepared using is abundant, can reach complete reaction, and successive processes to reach raw material stablize complete reaction be very the difficulty.

3. this technological process is prepared burden owing to be to adopt intermittently static weighing, and proportioning raw materials is accurate, the easy to control and operation of continuous production relatively.

4. adopt the heating of thermal oil or fused salt chuck, reaction zone stirs, the heat transfer efficiency height of reactor, and facility compact mixes, and reacts completely.

5. fluorite and sulfuric acid are preheating to 200-400 ℃, 100-280 ℃ respectively, and material is rapid at the reactor internal reaction, and the equipment of reactor is little, invests little.

6. the HF of reactor outlet is a static seal with the outlet of slag, dynamic seal with respect to rotary kiln input and output material port is simple, and the stir shaft trim is little, sealing easily, reactor is stable operation under positive pressure, has eliminated fully in the rotary kiln production technique because rotary system operation malleation causes HF gas to escape the hidden danger that environment is caused significant damage from the dynamic seal face of rotary kiln input and output material port.

7. this technological process adopts thermal oil or fused salt that heat is provided, and with respect to existing gas-fired hot air circulating system, system is simple and easy to control, and energy consumption is low, and cost is low.

Embodiment

Acid level fluorite powder and sulfuric acid are by the ratio of chemical reaction metering at first in the measuring chute outside reactor after accurate the metering, acid level fluorite powder joins in the reactor outside reactor after the preheating, or thermal oil or the fused salt preheating by chuck in reactor, stir simultaneously, when reaching, fluorite powder temperature progressively adds the sulfuric acid that measures after 200-400 ℃, sulfuric acid arrives 100-280 ℃ by a sulfuric acid heater heats before entering reactor, the HF gas that reaction produces is by outlet, be condensed after purifying cooling, distillation is used for producing the anhydrous hydrogen fluoride (AHF) of various requirement, or absorb to be produced hydrofluoric acid, or be used for direct production fluorine chemical derived product by water.

Claims

A kind of novel process of producing fluorine hydride by batch process, this technology comprises:

1. it is to provide the reactor discontinuous of the band whipping appts that chuck is arranged of heat to carry out by thermal oil or fused salt by external jacket that acid level fluorite powder and sulfuric acid reaction generate HF gas.
2. acid level fluorite powder and sulfuric acid measure outside reactor in the ratio of chemical reaction metering, the acid level fluorite powder that measures in reactor or outside be heated to 200-400 ℃ and be introduced into reactor, progressively join after the sulfuric acid that measures is heated to 100-280 ℃ in the reactor and react with acid level fluorite powder, and stir, reaction process is thermo-negative reaction, reactor temperature is by the outer chuck of reactor, provide heat by thermal oil or fused salt, the HF gas that reaction produces is through after purifying, a kind of mode is: condensation is got off, after process rectifying goes out high lower-boiling impurity, produce the anhydrous hydrogen fluoride (AHF) that meets various requirement; The second way: directly absorbing production by water has water hydrofluoric acid; The third mode: the derived product that directly is used for producing HF.
3. after reaction was finished, the gypsum tailings of generation thermal oil by chuck in reactor was cooled to the discharge of back below 100 ℃ reactor, or cools off gypsum tailings outside after discharging reactor; Finish the cycle of a reaction process.