CN106636652B - The technique of efficient green Recover palladium in a kind of parting liquid from silver anode slime - Google Patents

Abstract

The present invention provides a kind of technique of efficient green Recover palladium in parting liquid from silver anode slime, is broadly divided into the next stage：Parting liquid condensing crystallizing stage, concentrate sink silver-colored washing stage, oxidation and heavy palladium stage, removal of impurities purification phase, palladium reduction and drying stage.The technique is easy to operate all using conventional equipment, reagent cost economy used, and without adjusting the acid-base value of original solution, production efficiency is high, environmentally protective.Products obtained therefrom purity is high, high-quality, and the production practices of palladium are extracted suitable for low concentration liquid containing palladium.

Description

The technique of efficient green Recover palladium in a kind of parting liquid from silver anode slime

Technical field

The present invention relates to a kind of techniques of efficient green Recover palladium in parting liquid from silver anode slime, belong to noble metal wet method smelting Gold process technical field.

Background technology

Platinum family element content in the earth's crust is rare, and palladium is one kind of platinum group metal, with significant physicochemical properties, It is widely used, there is very important effect in the fields such as chemical industry, national defence scientific research.The synthetical recovery of Domestic Palladium is used mostly from two It is extracted in secondary resource, but secondary resource type is more, grade great disparity and impurity difference cause the generation rate of recovery low, process contamination The problems such as serious.

The main component of silver electrolysis anode slime is silver, gold and a small amount of platinum palladium metal, is leached silver and palladium using nitric acid Parting liquid is obtained, main component is silver nitrate.Common removes Ag⁺Agent is hydrochloric acid, if directly sinking silver using hydrochloric acid, hydrochloric acid dosage Greatly, the volatile operating condition of hydrochloric acid is poor, and a large amount of silver nitride precipitation of generation need to return to silver-colored pyrometallurgical smelting.Palladium in parting liquid Levels it is very low, should not directly be recycled, it is necessary to its concentration be improved using simple economy method and recycled again.

It 27 days 03 month, Chinese invention patent application publication number CN102994771A 2013, describes a kind of from silver electrolysis The method that palladium sponge is extracted in earth of positive pole parting liquid, major technique is to be enriched with palladium with palladium complex reaction using butyl xanthate, is used Concentrated hydrochloric acid and hydrogen peroxide leaching, filtrate refine again after adding in chlorination ammonia-sinking palladium, finally use hydrazine hydrate reduction.This method is first It needs to consume the pH that alkali adjusts solution, the precipitating reagent butyl xanthate then used is needed in higher temperature conditions（60~80℃）Under Operation, butyl xanthate, which easily decomposes, generates the toxic and harmful gas such as carbon disulfide, nitrogen oxides, hydrogen chloride, pollutes environment, is harmful to The health of shop floor worker.

On October 21st, 2015, Chinese invention patent application publication number CN104988315A describe acid Palladium recovery work Skill, method are with aqua regia dissolution palladium-containingmaterial material and denitration, with salt acid for adjusting pH to 1 ~ 1.5, after being adsorbed with basic anionic resin It takes off again and washes, dissolves, restoring the recycling for completing palladium.There are aqua regia dissolution, high temperature to catch up with the complex processes such as nitre, acidity adjustment for the technique, Working condition is poor, serious to environmental hazard；Adsorbed and taken off using resin and washed, due to resin price is higher and also need acid/ Alkali makes resin regeneration, while regenerated liquid needs are further processed, and make its overall operation costly.

Invention content

The purpose of the present invention is in view of the above-mentioned problems of the prior art, proposing that one kind is high from silver anode slime parting liquid The technique for imitating green reclaim palladium.This method uses Whote-wet method flow, and using conventional equipment, technological operation is simple, and process need not be caught up with Nitre, without adjusting the acid-base value of original solution；There is the advantages that pollution is small, environmental-friendly, palladium recovery rate is high and high-quality simultaneously, fit Close the research of the Recover palladium from low concentration liquid containing palladium.

The purpose of the present invention is realized by the following means：

The technique of efficient green Recover palladium in a kind of parting liquid from silver anode slime, it is characterised in that：With silver electrolysis anode slime For raw material, parting is dissolved through pernitric acid, recycling extraction is carried out to the palladium in parting liquid and silver；This method contains following rank Section：

Step 1：Parting liquid condensing crystallizing

Parting liquid is placed in low-temperature evaporation crystallizer, is careful not to excessively concentrate, to reduce palladium because crystallizing with silver nitrate Entrainment causes damages；When there are a large amount of silver nitrate crystals to generate, magma is gone to reservoir from crystallizer, after being cooled to room temperature Filtering washs separation of solid and liquid, gained silver nitrate crystal 1 ~ 2 time, and washing lotion and filtrate are mixed into concentrate, send to next process； Silver nitrate crystal heating water after washing carries out dissolving and returns to silver-colored potroom processing；

Step 2：Concentrate sink silver washing

Slightly excessive hydrochloric acid is added in into concentrate and is stirred continuously and carries out heavy silver, up to the generation of no white precipitate is as anti- Answer terminal；Filtered after standing 1 ~ 2 h, filter residue with hot water wash 1 ~ 2 time to reduce silver chlorate to the absorption of palladium and caused by lose, Silver chlorate as filter residue returns silver smelting recycling and produces thick silver, and gained filtrate and washing lotion, which are mixed, send next procedure；

Step 3：Oxidation and heavy palladium

The mixed liquor of step 2 gained filtrate and washing lotion is placed in reaction kettle, add in suitable sodium chlorate and is stirred continuously Half an hour, to ensure that palladium therein is all oxidized into Pd⁴⁺；It adds the ammonium chloride more excessive by 20% than theoretical amount and carries out heavy palladium, After being stirred to react 1 h of time, the filter residue for being obtained by filtration and being precipitated containing ammonium chloropalladate is stood, the ammonium chloride solution of filter residue saturation washs Next procedure is sent after 1 ~ 2 time, water process is sent after filtrate and washing lotion mixing；

Step 4：Removal of impurities purification

It is 3 that the filter residue deionized water containing ammonium chloropalladate that step 3 obtains is accumulated mass ratio by liquid solid:1mL/g is anti- It answers in container and mixes, heat and stir to dissolve simultaneously, until after red foam completely disappears, ammonium chloropalladite is obtained by filtration Solution, filter residue return to pyrogenic process recycling noble metal after being washed with appropriate hot water, washing lotion, which is poured into after being mixed with filtrate in reaction vessel, to be added Heat is to 85 ~ 90 DEG C, by 1：1 volume ratio adds in the pure ammonium hydroxide of chemistry, stirs simultaneously, and control terminal pH is 9 ~ 10；Solution is clarified After filter, be slowly added to the dilute hydrochloric acid acidification of configured 6 good mol/L, while mixing control solution acidification terminal pH is 1, is obtained It is precipitated to faint yellow dichloro diammonium network Asia palladium, stands cooled and filtered, dichloro diammonium network Asia palladium precipitation is washed with dilute hydrochloric acid solution Paste is tuned into deionized water afterwards twice, and adds in a certain amount of ammonium hydroxide and is stirred dissolving, until yellow mercury oxide disappears, Obtain the ammonia solution of dichloro diammonium network Asia palladium；

Step 5：Metal Palladium restores and drying

At normal temperatures, to step（4）In the ammonia solution of gained dichloro diammonium network Asia palladium, it is slowly added to the hydration of 200 g/L Hydrazine, without significant reaction and until solution transparent clear in solution when adding in hydrazine hydrate；Metal Palladium is obtained by filtration, Metal Palladium is used After deionized water washing under conditions of 150 ~ 180 DEG C drying to final products.

The silver chlorate of above-mentioned steps 2 returns silver smelting recycling and produces thick silver, is that silver nitride precipitation is returned the recycling of pyrogenic process system.

The beneficial effects of the present invention are the following aspects：

（1）Silver electrolysis anode slime parting liquid is concentrated using low-temperature evaporation crystallization technique, efficient, obvious energy conservation；The party Method can not only make the concentration raising of the palladium in parting liquid is convenient subsequently to be recycled to it, silver nitrate can also be made to be analysed with crystal habit Dissolving returns to silver-colored potroom processing after going out, and reduces precipitate A g⁺Required hydrochloric acid dosage；

（2）It is aoxidized with sodium chlorate and silver nitride precipitation is washed with hot water, to reduce the loss of palladium, by the way that chlorine is used in combination The palladium acid ammonium precipitation method and the two ammino Asia palladium precipitation method of dichloro refine to obtain Metal Palladium product, and this method removes various to greatest extent Impurity element improves the recycling efficiency of palladium resource；

（3）The technique and easy to operate, it is environmentally protective, it avoids the consumption of alkali and the high temperature of the butyl xanthate precipitation method is caught up with The complex processes such as nitre, roasting, it is highly practical, the production practices of palladium are extracted suitable for low concentration liquid containing palladium.

Description of the drawings

Fig. 1 is the process flow diagram of the present invention.

Specific embodiment

With reference to the accompanying drawings and detailed description to the present invention from silver anode slime parting liquid efficient green Recover palladium Technique is described in further detail.

Embodiment one

According to as shown in Figure 1 and said program process, by 0.5 m³The silver anode slime parting liquid of 0.816 g/L containing palladium put Magma is gone to reservoir when having a large amount of silver nitrate crystals to generate, is cooled to by the condensing crystallizing in low temperature MVR crystallizing evaporators By separation of solid and liquid, the washing lotion after gained silver nitrate crystal washs 2 times is mixed with filtrate, obtains 1.243 g/ containing palladium for filtering after room temperature The concentrate of L returns to silver-colored potroom processing after silver nitrate crystal dissolving.Concentrated hydrochloric acid is added in until silver all sedimentations, are filtered Silver nitride precipitation is washed to heavy silvering solution, and with hot water stirs, washing lotion is mixed with heavy silvering solution.30g/L sodium chlorate is added in be aoxidized, It is directly added into after stirring half an hour according still further to 150g/L ammonium chlorides and carries out heavy palladium, filter and wash ammonium chloropalladate precipitation.Use hot water It is completely dissolved ammonium chloropalladate, it is 9.0 that filtrate ammonia solvent, which adjusts pH, filters and the hydrochloric acid of 15 % is added in backward filtrate is acidified to PH is 1.0, and obtained yellow mercury oxide is washed with 5% dilute hydrochloric acid, is redissolved with after deionized water pulp with ammonium hydroxide, adjusts pH and is 9.0, filtering gained filtrate use 200 g/L hydrazine hydrate reduction, until react end and solution it is limpid it is transparent until, filtering drying Finally obtain palladium product.The process obtain the 99.89% of palladium product purity, the process palladium recovery rate is up to 85.2%.

Embodiment two

Silver anode slime parting liquid 0.931 g/L containing palladium, 1.522 g/L containing palladium after the concentration of low temperature MVR crystallizing evaporators, He is same as above example by principle process, the 99.92% of palladium product purity finally obtained, and the process palladium recovery rate is up to 86.5%.

Those of ordinary skills in the art should understand that：The above is only a specific embodiment of the present invention, and The limitation present invention is not used in, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done, It should be included within protection scope of the present invention.

Claims (2)

1. a kind of technique of efficient green Recover palladium in parting liquid from silver anode slime, it is characterised in that：Using silver electrolysis anode slime as Raw material dissolves parting through pernitric acid, recycling extraction is carried out to the palladium in parting liquid and silver；This method contains following several stages：

Step 1：Parting liquid condensing crystallizing

Parting liquid is placed in low-temperature evaporation crystallizer, is careful not to excessively concentrate, is carried secretly with reducing palladium because being crystallized with silver nitrate It causes damages；When there are a large amount of silver nitrate crystals to generate, magma is gone to reservoir from crystallizer, is filtered after being cooled to room temperature By separation of solid and liquid, gained silver nitrate crystal washs 1 ~ 2 time, and washing lotion and filtrate are mixed into concentrate, send to next process；Washing Silver nitrate crystal heating water afterwards carries out dissolving and returns to silver-colored potroom processing；

Step 2：Concentrate sink silver washing

Slightly excessive hydrochloric acid is added in into concentrate and is stirred continuously and carries out heavy silver, is to react eventually up to no white precipitate generates Point；Filtered after standing 1 ~ 2 h, filter residue with hot water wash 1 ~ 2 time to reduce silver chlorate to the absorption of palladium and caused by lose, as The silver chlorate of filter residue returns silver smelting recycling and produces thick silver, and gained filtrate and washing lotion, which are mixed, send next procedure；

Step 3：Oxidation and heavy palladium

The mixed liquor of step 2 gained filtrate and washing lotion is placed in reaction kettle, suitable sodium chlorate is added in and to be stirred continuously half small When, to ensure that palladium therein is all oxidized into Pd⁴⁺；It adds the ammonium chloride more excessive by 20% than theoretical amount and carries out heavy palladium, stirring After 1 h of reaction time, the filter residue for being obtained by filtration and being precipitated containing ammonium chloropalladate is stood, the ammonium chloride solution of filter residue saturation washs 1 ~ 2 Next procedure is sent after secondary, water process is sent after filtrate and washing lotion mixing；

Step 4：Removal of impurities purification

It is 3 that the filter residue deionized water containing ammonium chloropalladate that step 3 obtains is accumulated mass ratio by liquid solid:1mL/g holds in reaction It mixes in device, heat and stirs to dissolve simultaneously, until after red foam completely disappears, it is molten that ammonium chloropalladite is obtained by filtration Liquid, filter residue return to pyrogenic process recycling noble metal after being washed with appropriate hot water, washing lotion is poured into reaction vessel after being mixed with filtrate and heated To 85 ~ 90 DEG C, by 1：1 volume ratio adds in the pure ammonium hydroxide of chemistry, stirs simultaneously, and control terminal pH is 9 ~ 10；After solution clarification Filtering is slowly added to the dilute hydrochloric acid acidification of configured 6 good mol/L, while mixing control solution acidification terminal pH is 1, is obtained Faint yellow dichloro diammonium network Asia palladium precipitation, stands cooled and filtered, dichloro diammonium network Asia palladium precipitation washs two with dilute hydrochloric acid solution Paste is tuned into deionized water after secondary, and adds in a certain amount of ammonium hydroxide and is stirred dissolving, until yellow mercury oxide disappears, is obtained The ammonia solution of dichloro diammonium network Asia palladium；

Step 5：Metal Palladium restores and drying

At normal temperatures, to step（4）In the ammonia solution of gained dichloro diammonium network Asia palladium, the hydrazine hydrate of 200 g/L is slowly added to, directly When adding in hydrazine hydrate in solution without significant reaction and solution transparent clear until；Be obtained by filtration Metal Palladium, Metal Palladium spend from After sub- water washing under conditions of 150 ~ 180 DEG C drying to final products.

2. the technique of efficient green Recover palladium, feature exist in a kind of parting liquid from silver anode slime according to claim 1 Silver smelting recycling is returned in the silver chlorate of the step 2 and produces thick silver, is that silver nitride precipitation is returned into the recycling of pyrogenic process system.