CN1804060A - Wet chemical method for lead zinc composite extraction from lead zinc tailings - Google Patents

Abstract

The low-cost wet chemical method to composite purify the Pb-Zn as PZN ceramic material source from the tailings comprises: breaking the tailings to size less than 75mum; dissolving and cleaning the metal by 40-60% HNO3 to remove SiO2 and indissoluble sulfide; filtering, adding oxidizer to oxidize Fe and adjust pH as 5-5.5; filtering, adding NaOH solution to adjust pH to 7-8; filtering, cleaning the obtained hydroxide precipitate to put in crucible and calcine in chamber-type furnace at 700-850Deg for 2-5h. This invention has high leaching rate with little pollution.

Description

A kind of wet chemical method that Pb-Zn tailings is carried out the compound purification of plumbous zinc

Technical field

The invention belongs to chemical technology field, particularly proposed a kind of wet chemical method that Pb-Zn tailings is carried out the compound purification of plumbous zinc.

Background technology

Pb (Zn _1/3Nb _2/3) O ₃(PZN) dielectric ceramic material has the dielectric coefficient height (order of magnitude is 10 ⁴More than), temperature stability is good, and sintering temperature is low, and by many characteristics such as low percentage of capacitance variation with temperature that " disperse phase transformation " causes, is paid close attention to widely in fields such as laminated ceramic capacitor and electrostretch devices.In addition, the PZN material has very big electric field induced strain, and very little residual polarization and electric field induced strain lag behind, and advantages such as response is fast, zero restoring ability and good reproducibility, is the ideal material of making precision micro-displacement device, actuator and intelligent device.

Lead in the raw material of PZN pottery preparation and zinc source mainly are the pure lead and the salt or the oxide compound of zinc at present.Directly adopt the material property of pure feedstock production good, inclusion-free, but the salt of plumbous zinc all is to obtain by plumbous zinc metallurgical method in the raw material, the technological process of plumbous traditionally zinc metallurgy is independently carried out respectively, if can carry out the compound purification of plumbous zinc simultaneously, need not realize the separation of plumbous zinc, this not only makes smelting selection cost reduce, and shortens selecting-smelting process significantly.And the metallurgical main pyrometallurgy of adopting of plumbous traditionally zinc, well-known, the pyrometallurgy energy consumption is big, and because lead at high temperature is easy evaporable material, pyrometallurgical smelting is easy to cause plumbous loss, has not only influenced the plumbous rate of recovery, also can make operator's lead poisoning.Though more existing at present factories adopt the hydrometallurgy of zinc; but do not find the Wet-process metallurgy method of an ideal lead so far as yet; along with global environment conservation policy and the strictness day by day of industrial hygiene code requirement, the plumbous experimental study work of wet method refining more and more comes into one's own.

The inorganic chemistry method of utilizing acid-base neutralisation is a kind of important method in the hydrometallurgy, and its principle is that the pH value by regulator solution precipitates required metal hydroxides respectively.Satisfy Pb ²⁺, Zn ²⁺Sedimentary pH value is close, and precipitating the close ion of pH value with both has Cu ²⁺And Fe ²⁺, but in Pb-Zn tailings, only contain trace or do not contain Cu ²⁺, can't influence the performance for preparing the PZN material, in addition can be before the plumbous zinc of precipitation earlier with Fe ²⁺Be oxidized to ferric ion, in the pH value at 5～5.3 o'clock, Fe ³⁺Precipitated fully, and plumbous zinc precipitation not as yet basically, thus this will make Pb, Zn can with other separating substances.

The patent that present domestic employing wet chemistry method is handled plumbous zinc ore only has one piece, it is the full-wet process for pre-treating of 98112670.7 disclosed plumbous zinc ores, its purpose is for obtaining lead and zinc respectively, and control pH value is 4.1～5.2 can not be with Fe (OH) in its removal of impurities process ₂Precipitate Fe fully ²⁺With Fe (OH) ₂The line of delimitation be that this will be mixed in coprecipitation in the plumbous zinc at pH=6.6～9.15 places, this experiment before plumbous zinc precipitation with Fe ²⁺Oxidation.In addition, we invented carries out the concentration and the used oxygenant of the leaching solution of a kind of wet chemical method of the compound purification of plumbous zinc and above-mentioned patent to Pb-Zn tailings, and precipitation agent is all different.

Summary of the invention

The objective of the invention is to: a kind of wet chemical method that Pb-Zn tailings is carried out the compound purification of plumbous zinc is provided, be applicable to the cheap preparation method of the used compound material of PZN dielectric ceramic, adopt wet chemistry method to carry out the compound purification of plumbous zinc to Pb-Zn tailings, reduce the cost of raw material, and reduce pollution environment.

Utilize wet chemistry method to carry out the compound purification of plumbous zinc, processing step is:

A, pulverizing: Pb-Zn tailings is crushed to the sieve that granularity is crossed 75 μ m;

B, pickling: employing concentration is 40～60% nitric acid acidwashing, and purpose is a dissolved metal ions, removes the SiO in the raw ore ₂And infusibility sulfide;

C, deironing: solution after the above-mentioned pickling is leached filter residue, add oxygenant, with the iron oxidation, filter adjust pH to 5～5.5;

The compound purification of d, plumbous zinc: the solution that step 2 is obtained adds NaOH adjusting pH value to 7～8, filters, and filter residue is the precipitation of hydroxide of the plumbous zinc after the purification;

E, washing precipitation place crucible then, calcine 2～5 hours at 700～850 ℃ in box-type furnace.

After pulverizing, can carry out sulphur removal under the condition in 1～5 hour 750～850 ℃ of insulations, or not calcine direct pickling.

The method that the present invention proposes has following advantage:

(1) the leaching yield height of iron and zinc.Ionic concn before and after several solns filtered is carried out atomic spectroscopic analysis, and the result shows that the leaching yield of iron reaches 85.9%, and the leaching yield of zinc reaches 98.8%, the scum of the leaching preparation magneticsubstance of can purifying again.

(2) the compound purified product of plumbous zinc is purer.By XRD analysis, the thing in the product only finds to have ZnO, PbO mutually.

(3) technological operation is simple, and cost is low, and environmental pollution is little, can be used as the raw material sources of PZN stupalith.

Description of drawings

Fig. 1 is the process flow sheet of method of purification of the present invention.

Embodiment

Below introduce the specific embodiment of the present invention by description to embodiment.

Embodiment 1:

Present embodiment adopts Hunan China somewhere Pb-Zn tailings stone, and following table is the energy spectrum analysis of mineral:

Element	Mg	Al	Si	S	Ca	Fe	Zn	Pb
									The quality percentage composition	2.3015	1.8255	3.9436	5.4225	50.257	18.330	3.2476	14.671

With C, O, H substitution and above element combinations, obtain ZnO and the PbO total amount accounts for 9.23% of raw ore according to the material phase analysis result.Pb-Zn tailings is crushed to particle diameter less than 75 μ m, ore 10 grams of taking-up through pulverizing 800 ℃ of calcining sulphur removal in 3 hours down, add excessive concentrated nitric acid dissolving, leach insolubles, in filtrate, add excessive potassium permanganate, regulate pH value to 5.2, filter once more, regulate gained pH value of filtrate to 7.4, filter, this filter residue was calcined 3 hours under 800 ℃ in stove, obtain the 0.422g final product.Main thing is ZnO and PbO mutually in the product, and productive rate is near 45.8%.

Embodiment 2:

Adopt used ore among the embodiment 1, Pb-Zn tailings is crushed to particle diameter less than 76 μ m, takes out ore 20 grams, directly add excessive concentrated nitric acid dissolving without calcining through pulverizing, leach insolubles, in filtrate, add excessive potassium permanganate, regulate pH value to 5.4, filter once more, regulate gained pH value of filtrate to 7.8, filter, this filter residue was calcined 2 hours under 700 ℃ in stove, obtain final product 1.246g.Main thing is ZnO and PbO mutually in the product, and productive rate is near 67.5%.

Claims (2)

1, a kind of wet chemical method that Pb-Zn tailings is carried out the compound purification of plumbous zinc, processing step is:

A, pulverizing: Pb-Zn tailings is crushed to the sieve that granularity is crossed 75 μ m;

B, pickling: employing concentration is 40～60% nitric acid acidwashing, and dissolved metal ions is removed the SiO in the raw ore ₂And infusibility sulfide;

C, deironing: solution after the above-mentioned pickling is leached filter residue, add oxygenant, with the iron oxidation, filter adjust pH to 5～5.5;

The compound purification of d, plumbous zinc: the solution that step b is obtained adds NaOH adjusting pH value to 7～8, filters, and filter residue is the precipitation of hydroxide of the plumbous zinc after purifying;

E, washing precipitation place crucible then, calcine 2～5 hours at 700～850 ℃ in box-type furnace.

2, in accordance with the method for claim 1, it is characterized in that: after pulverizing, pickling after 750～850 ℃ of insulations were carried out sulphur removal under the condition in 1～5 hour.