CN103526039A - Method for preparing high purity rhodium trichloride by removing impurity from liquid phase digestion solution of waste rhodium catalyst - Google Patents
Method for preparing high purity rhodium trichloride by removing impurity from liquid phase digestion solution of waste rhodium catalyst Download PDFInfo
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Abstract
The invention discloses a method for preparing high purity rhodium trichloride by removing impurities from a liquid phase digestion solution of a waste rhodium catalyst. The method is characterized by comprising the following steps: step one, taking liquid phase digestion solution obtained by digesting waste rhodium catalyst for carbonyl synthesis with concentrated sulfuric acid and nitrate, adjusting to pH value to 1-5 by using sodium hydroxide, dropwise adding a sodium oxalate solution with stirring so that the solution becomes turbid, continuing adding the sodium oxalate solution until complete precipitation, stirring for 20-40 min and filtering to obtain the filtrate, wherein the concentration of sodium oxalate solution is 1-10 wt%; and two, directly heating the filtrate obtained in the step one or diluting the filtrate with deionized water by 10 times and heating to a boiling state, adjusting the pH value to 8 with 1%-15% sodium hydroxide solution, stirring and filtering to obtain a rhodium gel; and dissolving the rhodium gel in 6 mol /L hydrochloric acid, and evaporating, concentrating and drying the solution to obtain high-purity three rhodium trichloride. The method of the invention is applicable to recovery of noble metal rhodium from the waste rhodium catalyst from carbonyl synthesis, and is economical and environment-friendly; and the method has the advantages of mild reaction conditions, simple operation and easiness for industrialization.
Description
Technical field
The present invention relates to a kind of spent rhodium catalyst digestion solution and remove the method that foreign ion is prepared high-purity Trichlororhodium, more specifically say from the liquid phase digestion solution of oxo process spent rhodium catalyst and reclaim the method that Noble Metal Rhodium is prepared high-purity Trichlororhodium.
Background technology
Rhodium phosphine complex catalyst, as one of the most frequently used catalyzer of carbongl group synthesis reaction on chemical industry, has series of advantages, as has high catalytic activity, catalytic reaction condition is gentle, lower to equipment requirements, simultaneously appropriate phosphine part add the positive isomery ratio that can improve product, improve the output value.But in long-term Industrial processes, foreign matter can reduce the activity of rhodium catalyst, the generation of rhodium clusters simultaneously makes its inner inactivation, when catalyst activity reduction will be carried out the replacing of catalyzer to certain level.Rhodium is rare as Precious Metals Resources, expensive, so the recycling of spent rhodium catalyst is significant.
In oxo process spent rhodium catalyst, the recovery of rhodium obtains people's extensive concern, has also formed severally compared with effective means, mainly comprises partition method, combustion method and liquid phase degestion.Wherein partition method comprises extraction process, adsorption method of separation and the amination liberation method that dissociates, and these class methods need to consume a large amount of solvents, and technique is comparatively complicated, and the rate of recovery is not high.Combustion method mainly comprises submerged combustion and ashing combustion method, and these class methods are more in industrial application, and the rhodium rate of recovery can reach 96%, but can produce a large amount of waste water, waste gas in rhodium removal process, and environmental pollution is serious, and higher to equipment requirements.The liquid phase degestion of oxo process spent rhodium catalyst has overcome the deficiency of aforesaid method, introduces below.
Chinese patent ZL200710177195.7 has introduced a kind of method that reclaims Trichlororhodium spent rhodium catalyst that adopts liquid phase method to produce from carbongl group synthesis reaction, the method adopts mineral acid and oxygenant to clear up spent rhodium catalyst, rhodium exists in solution with the form of soluble rhodium salt, through processing and refining, obtain high purity hydrous rhodium chloride, wherein high, the economic environmental protection of the rhodium rate of recovery, easy to operate.But the mineral acid that the method adopts (referring to two or more the mixture in the sulfuric acid, hydrochloric acid, nitric acid, perchloric acid of high density) has strong volatility mostly, with oxygenant high temperature under can occur decompose rapidly and volatilize in clearing up the process of catalyzer, in simultaneous reactions, also have water to generate, so reduce the efficiency of clearing up, extended digestion time.Chinese patent CN102492845A has introduced a kind of liquid phase digestion procedure of improved oxo process spent rhodium catalyst, the method adopts the vitriol oil by spent rhodium catalyst charing, then add base metal nitrate solid, control temperature at 160～220 ℃, can high efficiency spent rhodium catalyst be cleared up completely.The method has been avoided the application of a large amount of volatile acids, and operational condition is gentle.But the use of a large amount of inorganic salt can be introduced certain impurity, as calcium ion, and can produce inrichment in the process of the synthetic rhodium gel of postorder, be not easy to remove, at present less for the impurity removal process of calcium ion.Chinese patent CN1025158286A has introduced the method that high purity Trichlororhodium is prepared in the removal of impurities of a kind of spent rhodium catalyst digestion solution, the method will add soluble barium salt to remove sulfate ion after the dilution of spent rhodium catalyst digestion solution, add ammonium molybdate to remove phosphate anion, gained solution is removed other ionic impurities through ion exchange resin, and the rhodium rate of recovery reaches more than 99%.Ion exchange resin impurity-removing method requires pending sample concentration extremely rare, and a large amount of water of so just will using up, makes follow-up concentrated energy consumption larger.
Summary of the invention
The object of the invention is the deficiency for above-mentioned art methods, a kind of simple method of being prepared efficiently high-purity Trichlororhodium by oxo process spent rhodium catalyst digestion solution is provided.Present method is the precipitating action to calcium ion by oxalate, make calcium ion be filtered and remove with the form of caoxalate, water-soluble rhodium salt in filtrate is synthetic rhodium gel at high temperature, and other foreign ions can be removed by washing, and the acid treating of rhodium gel salt adding is obtained to high-purity Trichlororhodium.The method is simple to operate, the rhodium rate of recovery is high, has economy simultaneously, has avoided the shortcoming that in ion exchange process, efficiency is low, energy consumption is large.
The raw material the present invention is directed to is that the vitriol oil and nitrate are cleared up the liquid phase digestion solution that oxo process spent rhodium catalyst obtains, the main component of this digestion solution is that sulfuric acid, sodium ion and spent rhodium catalyst phosphine part are cleared up the phosphate radical of generation, the calcium ion that also has in addition Noble Metal Rhodium and enrichment, and the iron of trace, nickel etc.In digestion solution, the mass content of rhodium is 0.02～0.5%.
A certain amount of calcium ion is introduced in the membership that adds of nitrate in liquid phase digestion process of oxo process spent rhodium catalyst, and along with the calcium ion that carries out of clearing up obtains enrichment, with the form of calcium sulfate, is present in digestion solution.At high temperature add in the process of hot preparation rhodium gel, other water-soluble impurity ions can be removed by the mode of washing, but the solubleness of calcium sulfate declines along with the rising of temperature, under high temperature, calcium sulphate solid is separated out by rhodium gel pack wrapped folder band, causes calcium contents in synthetic Trichlororhodium to exceed standard.
Oxalate has good precipitating action to calcium ion, according to this feature, in the digestion solution of spent rhodium catalyst, adds sodium oxalate, and impurity calcium ion is removed, and oxalate is removed with the form of carbonic acid gas simultaneously, can not bring new impurity to system.Useless rhodium digestion solution after deliming regulates pH to obtain rhodium gel to alkalescence.In this building-up process, on the one hand, rarer reaction solution concentration can prepare the rhodium gel of larger particles, is conducive to the eccysis of other foreign ions; On the other hand, excess dilution reaction solution is unfavorable for industrial production operation, therefore will consider the factor of this two aspect.
The invention provides the removal of impurities of a kind of spent rhodium catalyst liquid phase digestion solution and prepare the method for high-purity Trichlororhodium, it is characterized in that, it comprises the following steps:
The first step, gets the vitriol oil and nitrate and clears up the liquid phase digestion solution that oxo process spent rhodium catalyst obtains, and with sodium hydroxide, is adjusted to pH=1～5, under agitation condition, drip sodium oxalate solution, make solution become muddy, continue to drop to precipitation completely, stir 20-40 minute, filter, obtain filtrate, wherein, in described spent rhodium catalyst liquid phase digestion solution, contain Noble Metal Rhodium, and the spent rhodium catalyst liquid phase digestion solution of sodium, calcium, iron and nickel metallic impurity, the concentration of described sodium oxalate solution is 1～10wt%;
Second step, obtains the first step described filtrate direct heating or dilutes 10 times of post-heating to micro-boiling with deionized water, with 1wt%～15wt% sodium hydroxide solution, is adjusted to pH=8, stirs, filters, and obtains rhodium gel; After described rhodium gel is dissolved in 6mol/L hydrochloric acid, by this solution evaporation, after concentrated, dry, obtain high purity Trichlororhodium.
According to aforesaid method of the present invention, preferably include following steps:
The first step, get oxo process spent rhodium catalyst liquid phase digestion solution, with sodium hydroxide, be adjusted to pH=3～4, under agitation condition, drip sodium oxalate solution, make solution become muddy, continue to drop to precipitation completely, stir 30 minutes, filter, obtain filtrate, wherein, rhodium content 0.02～0.5wt% in described oxo process spent rhodium catalyst liquid phase digestion solution, other metals content impurities are: sodium 10～15wt%, calcium 0.01～0.06wt%, iron 0.01～0.04wt%, nickel 0.001～0.004wt%, and the concentration of sodium oxalate solution is 1～10wt%;
Second step, obtains the first step described filtrate direct heating or dilutes 10 times of post-heating to micro-boiling with deionized water, with the sodium hydroxide solution of 1wt%～15wt%, regulates pH=8, and stirring, filtration, obtain rhodium gel; Described rhodium gel is dissolved in 6mol/L hydrochloric acid, by this solution evaporation, after concentrated, dry, obtains high purity Trichlororhodium.
According to aforesaid method of the present invention, more preferably comprise the following steps:
The first step, gets oxo process spent rhodium catalyst liquid phase digestion solution, with sodium hydroxide, is adjusted to behind pH=3～4, under agitation condition, drips sodium oxalate solution, now solution becomes muddy, continues to drop to precipitation completely, stirs 30 minutes, filter, obtain filtrate, wherein the concentration of sodium oxalate solution is 10wt%;
Second step, obtains described filtrate by the first step and dilutes 10 times of post-heating to micro-boiling with deionized water, with the sodium hydroxide solution of 1wt%, regulates pH=8, and stirring, filtration, obtain rhodium gel; Rhodium gel is dissolved in 6mol/L hydrochloric acid, by this solution evaporation, after concentrated, dry, obtains high purity Trichlororhodium.
The invention provides a kind of spent rhodium catalyst digestion solution and prepare the method for high-purity Trichlororhodium, the method is applicable to the recovery of Noble Metal Rhodium in oxo process spent rhodium catalyst, economic environmental protection, and processing condition are gentle, simple to operate, are easy to industrialization.
Embodiment
The present invention further illustrates the present invention by following embodiment, but does not form limiting the scope of the invention.
Embodiment 1:
The first step, get spent rhodium catalyst digestion solution (rhodium content 0.02～0.5wt%, other metals content impurities are: sodium 10～15wt%, calcium 0.01～0.06wt%, iron 0.01～0.04wt%, nickel 0.001～0.004wt%) 30g, with sodium hydroxide, regulate rhodium salt solution pH=1.5.Under stirring, adding mass concentration is 1% sodium oxalate solution 130g.Above-mentioned mixed solution continues to stir 30 minutes, filters, and obtains clear filtrate.
Second step, dilutes 10 times of post-heating to slight boiling condition by filtrate with deionized water, and the sodium hydroxide solution that slowly drips 1wt% regulates pH=8, now separates out a large amount of yellow flosss, and heat filtering, fully washs with deionized water, obtains rhodium gel.The dissolving with hydrochloric acid rhodium gel of preparation 6mol/L, then by the rhodium salt solution evaporation obtaining, concentrated, dry, obtain Trichlororhodium.The demonstration of analyzing and testing result, Trichlororhodium impurity element total amount 0.046%, meets YS/T593-2006 first grade quality index.As calculated, rhodium yield 99.6%.
Rhodium yield adopts following formula to calculate:
The rhodium rate of recovery=(mass content of rhodium in rhodium chloride quality * rhodium chloride)/(mass content of rhodium in digestion solution quality * digestion solution) * 100%
Digestion solution rhodium content detects with icp analysis, and in Trichlororhodium, rhodium content is analyzed by weighting method.
Each foreign matter content detects with icp analysis.
Embodiment 2:
Operating process is with embodiment 1, and different is in the first step, to regulate pH=3.5.Gained Trichlororhodium analyzing and testing result shows Trichlororhodium impurity element total amount 0.039%, meets YS/T593-2006 first grade quality index.As calculated, rhodium yield 99.8%.
Embodiment 3:
Operating process is with embodiment 1, and different is in the first step, to regulate pH=5.Gained Trichlororhodium analyzing and testing result shows Trichlororhodium impurity element total amount 0.042%, meets YS/T593-2006 first grade quality index.As calculated, rhodium yield 99.4%.
Embodiment 4:
Operating process is with embodiment 2, and different is under stirring, to add the sodium oxalate solution 65g of 10wt%.Gained Trichlororhodium analyzing and testing result shows Trichlororhodium impurity element total amount 0.036%, meets YS/T593-2006 first grade quality index.As calculated, rhodium yield 99.8%.
Embodiment 5:
Operating process is with embodiment 2, and different is in second step by filtrate direct heating to slight boiling condition, adds 10% sodium hydroxide solution to regulate pH=8.Gained Trichlororhodium analyzing and testing result shows Trichlororhodium impurity element total amount 0.047%, meets YS/T593-2006 first grade quality index.As calculated, rhodium yield 99.4%.
Claims (3)
1. a method for high-purity Trichlororhodium is prepared in the removal of impurities of spent rhodium catalyst liquid phase digestion solution, it is characterized in that, it comprises the following steps:
The first step, get the vitriol oil and nitrate and clear up the liquid phase digestion solution that oxo process spent rhodium catalyst obtains, with sodium hydroxide, be adjusted to pH=1～5, under agitation condition, drip sodium oxalate solution, make solution become muddy, continue to drop to precipitation completely, stir 20-40 minute, filter, obtain filtrate, in wherein said spent rhodium catalyst liquid phase digestion solution, contain Noble Metal Rhodium, and sodium, calcium, iron and nickel metallic impurity, the concentration of described sodium oxalate solution is 1～10wt%;
Second step, obtains the first step described filtrate direct heating or dilutes 10 times of post-heating to micro-boiling with deionized water, with 1wt%～15wt% sodium hydroxide solution, is adjusted to pH=8, stirs, filters, and obtains rhodium gel; After described rhodium gel is dissolved in 6mol/L hydrochloric acid, by this solution evaporation, after concentrated, dry, obtain high purity Trichlororhodium.
2. method according to claim 1, is characterized in that, comprises the following steps:
The first step, get oxo process spent rhodium catalyst liquid phase digestion solution, with sodium hydroxide, be adjusted to pH=3～4, under agitation condition, drip sodium oxalate solution, make solution become muddy, continue to drop to precipitation completely, stir 30 minutes, filter, obtain filtrate, rhodium content 0.02～0.5wt% in wherein said oxo process spent rhodium catalyst liquid phase digestion solution, other metals content impurities are: sodium 10～15wt%, calcium 0.01～0.06wt%, iron 0.01～0.04wt%, nickel 0.001～0.004wt%; The concentration of described sodium oxalate solution is 1～10wt%;
Second step, obtains the first step described filtrate direct heating or dilutes 10 times of post-heating to micro-boiling with deionized water, with the sodium hydroxide solution of 1wt%～15wt%, regulates pH=8, and stirring, filtration, obtain rhodium gel; Described rhodium gel is dissolved in 6mol/L hydrochloric acid, by this solution evaporation, after concentrated, dry, obtains high purity Trichlororhodium.
3. method according to claim 1, is characterized in that, comprises the following steps:
The first step, gets oxo process spent rhodium catalyst liquid phase digestion solution, with sodium hydroxide, is adjusted to behind pH=3～4, under agitation condition, drips sodium oxalate solution, now solution becomes muddy, continues to drop to precipitation completely, stirs 30 minutes, filter, obtain filtrate, wherein the concentration of sodium oxalate solution is 10wt%;
Second step, obtains described filtrate by the first step and dilutes 10 times of post-heating to micro-boiling with deionized water, and the sodium hydroxide solution with 1% regulates pH=8, stirs, filters, and obtains rhodium gel; Described rhodium gel is dissolved in after 6mol/L hydrochloric acid, by this solution evaporation, after concentrated, dry, obtains high purity Trichlororhodium.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104402068A (en) * | 2014-11-07 | 2015-03-11 | 中国海洋石油总公司 | Method for preparing high-purity rhodium trichloride from carbonyl-synthetic-reaction waste rhodium catalyst degradation solution |
| CN105463202A (en) * | 2015-12-09 | 2016-04-06 | 中国海洋石油总公司 | Method for preparing high-purity rhodium chloride by removing impurities from impurity-containing chlororhodic acid solution |
| CN109930006A (en) * | 2019-04-16 | 2019-06-25 | 福建工程学院 | A method of noble metal platinum in recycling TDI tar residue |
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| CN101012165A (en) * | 2007-02-09 | 2007-08-08 | 李安民 | Process of preparing oxalic acid by calcium sulfate cycle method |
| CN102492845A (en) * | 2011-11-14 | 2012-06-13 | 中国海洋石油总公司 | Method for digesting spent rhodium catalyst in carbonyl group synthetic reaction |
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| CN101012165A (en) * | 2007-02-09 | 2007-08-08 | 李安民 | Process of preparing oxalic acid by calcium sulfate cycle method |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104402068A (en) * | 2014-11-07 | 2015-03-11 | 中国海洋石油总公司 | Method for preparing high-purity rhodium trichloride from carbonyl-synthetic-reaction waste rhodium catalyst degradation solution |
| CN104402068B (en) * | 2014-11-07 | 2016-07-13 | 中国海洋石油总公司 | The method that carbongl group synthesis reaction spent rhodium catalyst digestion solution prepares high-purity rhodium chloride |
| CN105463202A (en) * | 2015-12-09 | 2016-04-06 | 中国海洋石油总公司 | Method for preparing high-purity rhodium chloride by removing impurities from impurity-containing chlororhodic acid solution |
| CN105463202B (en) * | 2015-12-09 | 2017-10-13 | 中海油天津化工研究设计院有限公司 | A kind of method that impure chlorine rhodium acid solution removal of impurities prepares high-purity rhodium chloride |
| CN109930006A (en) * | 2019-04-16 | 2019-06-25 | 福建工程学院 | A method of noble metal platinum in recycling TDI tar residue |
| CN109930006B (en) * | 2019-04-16 | 2020-12-25 | 福建工程学院 | Method for recovering noble metal platinum in TDI tar residue |
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Application publication date: 20140122 |