CN110412640B - Method for detecting radioactive separation degree in lanthanum chloride and application thereof - Google Patents
Method for detecting radioactive separation degree in lanthanum chloride and application thereof Download PDFInfo
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- ICAKDTKJOYSXGC-UHFFFAOYSA-K lanthanum(iii) chloride Chemical compound Cl[La](Cl)Cl ICAKDTKJOYSXGC-UHFFFAOYSA-K 0.000 title claims abstract description 97
- 230000002285 radioactive effect Effects 0.000 title claims abstract description 67
- 238000000034 method Methods 0.000 title claims abstract description 40
- 238000000926 separation method Methods 0.000 title claims abstract description 36
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 claims abstract description 66
- 229910001424 calcium ion Inorganic materials 0.000 claims abstract description 66
- 239000011259 mixed solution Substances 0.000 claims abstract description 55
- -1 actinium ions Chemical class 0.000 claims abstract description 32
- 229910052767 actinium Inorganic materials 0.000 claims abstract description 23
- 239000003350 kerosene Substances 0.000 claims abstract description 21
- 229910052761 rare earth metal Inorganic materials 0.000 claims abstract description 16
- 150000002910 rare earth metals Chemical class 0.000 claims abstract description 16
- 238000001514 detection method Methods 0.000 claims abstract description 11
- 238000004519 manufacturing process Methods 0.000 claims abstract description 10
- 238000012545 processing Methods 0.000 claims abstract description 10
- 229910052746 lanthanum Inorganic materials 0.000 claims description 59
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 claims description 48
- 239000000243 solution Substances 0.000 claims description 44
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical group Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 36
- 239000012527 feed solution Substances 0.000 claims description 30
- 238000000605 extraction Methods 0.000 claims description 29
- 239000003795 chemical substances by application Substances 0.000 claims description 28
- 238000007127 saponification reaction Methods 0.000 claims description 11
- 239000002253 acid Substances 0.000 claims description 3
- GPRLSGONYQIRFK-UHFFFAOYSA-N hydron Chemical compound [H+] GPRLSGONYQIRFK-UHFFFAOYSA-N 0.000 claims description 3
- CZMAIROVPAYCMU-UHFFFAOYSA-N lanthanum(3+) Chemical compound [La+3] CZMAIROVPAYCMU-UHFFFAOYSA-N 0.000 claims 2
- 239000011575 calcium Substances 0.000 description 26
- 229910052791 calcium Inorganic materials 0.000 description 13
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 12
- 230000000694 effects Effects 0.000 description 6
- 238000005259 measurement Methods 0.000 description 3
- 239000012535 impurity Substances 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- MKYBYDHXWVHEJW-UHFFFAOYSA-N N-[1-oxo-1-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propan-2-yl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(C(C)NC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 MKYBYDHXWVHEJW-UHFFFAOYSA-N 0.000 description 1
- QQINRWTZWGJFDB-UHFFFAOYSA-N actinium atom Chemical compound [Ac] QQINRWTZWGJFDB-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- IKNAJTLCCWPIQD-UHFFFAOYSA-K cerium(3+);lanthanum(3+);neodymium(3+);oxygen(2-);phosphate Chemical compound [O-2].[La+3].[Ce+3].[Nd+3].[O-]P([O-])([O-])=O IKNAJTLCCWPIQD-UHFFFAOYSA-K 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000004070 electrodeposition Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052590 monazite Inorganic materials 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000000941 radioactive substance Substances 0.000 description 1
- 238000005514 radiochemical analysis Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000004611 spectroscopical analysis Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/02—Dosimeters
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/16—Measuring radiation intensity
- G01T1/167—Measuring radioactive content of objects, e.g. contamination
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- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Physics & Mathematics (AREA)
- High Energy & Nuclear Physics (AREA)
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- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
本发明涉及稀土加工技术领域，本发明实施例提供一种检测氯化镧中放射性分离程度的方法，包括：采用皂化P507‑煤油萃取剂对含有钙离子和锕离子的氯化镧混合溶液进行萃取分离使氯化镧混合溶液脱除钙离子和锕离子，测算钙离子的脱除率以评价氯化镧混合溶液的放射性脱除程度。该方法在钙离子和锕离子脱除后即可计算钙离子的脱除率，以钙离子的脱除率反映放射性脱除程度，相较于现有技术脱除后放置140天才能准确检测放射性脱除率而言，本申请不需要长时间放置等待，大大提高了检测效率。当本发明提供的检测方法应用于稀土加工生产中时，由于放射性脱除率的检测效率大大提高，因此能够大大提高稀土生产加工的效率。The present invention relates to the technical field of rare earth processing. An embodiment of the present invention provides a method for detecting the degree of radioactive separation in lanthanum chloride, comprising: extracting a mixed solution of lanthanum chloride containing calcium ions and actinium ions by using a saponified P507-kerosene extractant The lanthanum chloride mixed solution was separated to remove calcium ions and actinium ions, and the removal rate of calcium ions was calculated to evaluate the radioactive removal degree of the lanthanum chloride mixed solution. In this method, the removal rate of calcium ions can be calculated after the removal of calcium ions and actinium ions, and the removal rate of calcium ions can reflect the degree of radioactive removal. In terms of removal rate, the present application does not need to wait for a long time, which greatly improves the detection efficiency. When the detection method provided by the present invention is applied to rare earth processing and production, since the detection efficiency of the radioactive removal rate is greatly improved, the efficiency of rare earth production and processing can be greatly improved.
Description
技术领域technical field
本发明涉及稀土加工技术领域，具体而言，涉及检测氯化镧中放射性分离程度的方法及其应用。The invention relates to the technical field of rare earth processing, in particular to a method for detecting the degree of radioactive separation in lanthanum chloride and its application.
背景技术Background technique
稀土矿物均含有一定数量的放射性物质，且不同的稀土矿物的放射性元素含量有较大的差别。过去人们对稀土放射性研究工作主要集中于独居石、氟碳铈矿及其混合矿方面，然而我国的离子型稀土矿也含有一些放射性元素。由于离子型稀土矿中含有一些放射性元素Ac227，227Ac虽是一个β放射体，但它产生一系列短寿命的α子体，属于极毒类天然放射性核素，相对危险度远甚于226Ra。227Ac在元素周期表中位于La的下面，其化学性质与La系相似，在镧产品中难以除掉，它们是氧化镧中放射性的主要来源。227Ac是235U的子体，227Ac(锕)与U的平衡含量为2×10-8％，氯化镧经萃取分离，U和其他的放射性核素会被除掉，由于放射性母体的去除，这时227Ac的放射性开始增长，它与五个α子体在140天左右达到放射性平衡，其放射性增长的倍数可达数百倍之多。因此，镧产品在刚生产出来时的放射性可能是很低的，但放置一段时间后会显著增加，只有在达到放射平衡后(140天左右)检测的放射性数据才能反映该产品放射性的真实水平。目前，227Ac的测定方法有放化分析法、离子交换、电沉积和α能谱等，这些方法，步骤繁多、专一性强，稀土企业还没有该类设备。由于无法及时、准确地分析生产工艺中的镧产品放射性是否达标，无法指导生产，导致生产出镧产品的放射性经常远远超过标准，因而严重影响了其使用和出口。因此，急需寻找一种快速检测氯化镧中放射性分离程度的方法。Rare earth minerals all contain a certain amount of radioactive substances, and the radioactive element content of different rare earth minerals is quite different. In the past, people's research work on rare earth radioactivity mainly focused on monazite, bastnaesite and its mixed ores. However, ionic rare earth ores in my country also contain some radioactive elements. Because ionic rare earth ore contains some radioactive elements Ac227, although 227Ac is a beta emitter, it produces a series of short-lived alpha daughters, which are extremely toxic natural radionuclides, and the relative risk is much higher than 226Ra. 227Ac is located below La in the periodic table. Its chemical properties are similar to La series, and it is difficult to remove in lanthanum products. They are the main source of radioactivity in lanthanum oxide. 227Ac is the daughter of 235U, and the equilibrium content of 227Ac (actinium) and U is 2×10 -8 %. After lanthanum chloride is extracted and separated, U and other radionuclides will be removed. When the radioactivity of 227Ac began to increase, it and the five α daughters reached a radioactive balance in about 140 days, and the radioactivity increased by several hundreds of times. Therefore, the radioactivity of the lanthanum product may be very low when it is just produced, but it will increase significantly after a period of time. Only the radioactivity data detected after reaching the radioactivity balance (about 140 days) can reflect the true level of the product's radioactivity. At present, the determination methods of 227Ac include radiochemical analysis, ion exchange, electrodeposition and alpha energy spectroscopy, etc. These methods have many steps and strong specificity, and rare earth enterprises do not have such equipment. Due to the inability to timely and accurately analyze whether the radioactivity of lanthanum products in the production process meets the standards, and to guide the production, the radioactivity of the lanthanum products produced often far exceeds the standards, thus seriously affecting their use and export. Therefore, it is urgent to find a method to rapidly detect the degree of radioactive separation in lanthanum chloride.
鉴于此，特提出本发明。In view of this, the present invention is proposed.
发明内容SUMMARY OF THE INVENTION
本发明提供一种检测氯化镧中放射性分离程度的方法，旨在改善现有的氯化镧溶液中放射性脱除程度的检测周期过长的问题。The present invention provides a method for detecting the degree of radioactive separation in lanthanum chloride, aiming to improve the problem that the detection period of the degree of radioactive removal in the existing lanthanum chloride solution is too long.
本发明是这样实现的：The present invention is realized in this way:
第一方面，本发明实施例提供一种检测氯化镧中放射性分离程度的方法，包括：In the first aspect, the embodiment of the present invention provides a method for detecting the degree of radioactive separation in lanthanum chloride, comprising:
采用皂化P507-煤油萃取剂对含有钙离子和锕离子的氯化镧混合溶液进行萃取分离，测算钙离子的脱除率以评价氯化镧混合溶液的放射性脱除程度。The saponified P507-kerosene extractant was used to extract and separate the mixed solution of lanthanum chloride containing calcium ions and actinium ions, and the removal rate of calcium ions was measured to evaluate the degree of radioactive removal of the mixed solution of lanthanum chloride.
在可选的实施方式中，包括：In optional embodiments, including:
向含有钙离子和锕离子的氯化镧混合溶液中加入皂化P507-煤油萃取剂对氯化镧混合溶液进行萃取以分离脱除氯化镧混合溶液中的钙离子和锕离子，得到负载镧萃取剂。Adding saponified P507-kerosene extractant to the mixed solution of lanthanum chloride containing calcium ions and actinium ions to extract the mixed solution of lanthanum chloride to separate and remove the calcium ions and actinium ions in the mixed solution of lanthanum chloride to obtain loaded lanthanum extraction agent.
向负载镧萃取剂中加入反萃取剂进行反萃取得到含有镧离子和钙离子的镧料液。A stripping agent is added to the loaded lanthanum extractant for stripping to obtain a lanthanum feed solution containing lanthanum ions and calcium ions.
测定镧料液中钙离子含量，计算镧料液相对于氯化镧混合溶液钙离子的脱除率评价氯化镧混合溶液的放射性脱除率。The content of calcium ions in the lanthanum feed solution was measured, and the removal rate of calcium ions from the lanthanum feed solution to the lanthanum chloride mixed solution was calculated to evaluate the radioactive removal rate of the lanthanum chloride mixed solution.
在可选的实施方式中，还包括检测反萃取剂中钙离子的量，以W1表示氯化镧混合溶液中钙离子的量，以W2表示反萃取剂中钙离子的量，以W3表示镧料液中钙离子的量；钙离子的脱除率等于(W1+W2-W3)/W1。In an optional embodiment, it also includes detecting the amount of calcium ions in the stripping agent, with W 1 representing the amount of calcium ions in the lanthanum chloride mixed solution, with W 2 representing the amount of calcium ions in the stripping agent, with W 3 represents the amount of calcium ions in the lanthanum feed solution; the removal rate of calcium ions is equal to (W 1 +W 2 -W 3 )/W 1 .
在可选的实施方式中，皂化P507-煤油萃取剂的皂化率为20～50％；皂化P507-煤油萃取剂中P507浓度为1.2～1.8mol/L。In an optional embodiment, the saponification rate of the saponified P507-kerosene extractant is 20-50%; the concentration of P507 in the saponified P507-kerosene extractant is 1.2-1.8 mol/L.
在可选的实施方式中，皂化P507-煤油萃取剂的用量与氯化镧混合溶液中镧离子之比为6～20L:1.5mol。In an optional embodiment, the ratio of the amount of the saponified P507-kerosene extractant to the lanthanum ions in the lanthanum chloride mixed solution is 6-20L:1.5mol.
在可选的实施方式中，反萃取剂为氢离子浓度为4～5mol/L的酸液。In an optional embodiment, the stripping agent is an acid solution with a hydrogen ion concentration of 4-5 mol/L.
在可选的实施方式中，反萃取剂为盐酸。In an alternative embodiment, the stripping agent is hydrochloric acid.
在可选的实施方式中，反萃取剂的用量与氯化镧混合溶液中镧离子之比为1～2L:1.5mol。In an optional embodiment, the ratio of the amount of the stripping agent to the lanthanum ions in the lanthanum chloride mixed solution is 1-2L:1.5mol.
在可选的实施方式中，萃取为多级萃取。In an alternative embodiment, the extraction is a multistage extraction.
第二方面，本发明实施例提供如前述实施方式任一项的方法在稀土加工成产中的应用。In a second aspect, the embodiments of the present invention provide the application of the method according to any one of the foregoing embodiments in rare earth processing and production.
本发明具有以下有益效果：The present invention has the following beneficial effects:
本发明利用在P507萃取分离氯化镧体系中，P507对227Ac和Ca2+萃取性能相似的特点，采用Ca2+的分离脱除效果来评价227Ac的脱除效果。该方式可以使得放射性脱除程度在脱除操作完后立即计算得到。相较于现有的将溶液放置140天后再进行测量，大大缩短了氯化镧溶液放射性脱除程度的检测时间，可快速判断经放射性脱除处理的氯化镧溶液中放射性含量是否达标。其该方法无须昂贵设备，实验以及分析过程简单方便，实用性强。The present invention utilizes the characteristic that P507 has similar extraction performance to 227Ac and Ca 2+ in the system of P507 extraction and separation of lanthanum chloride, and uses the separation and removal effect of Ca 2+ to evaluate the removal effect of 227Ac. This method allows the degree of radioactive removal to be calculated immediately after the removal operation. Compared with the existing measurement after the solution is placed for 140 days, the detection time of the radioactive removal degree of the lanthanum chloride solution is greatly shortened, and it can be quickly judged whether the radioactive content in the radioactively removed lanthanum chloride solution reaches the standard. The method does not need expensive equipment, the experiment and analysis process are simple and convenient, and the practicability is strong.
本发明设计得到的检测氯化镧中放射性分离程度的方法应用于稀土加工生产过程中时，由于大大缩短了放射性脱除程度检测时间，由此能够提高稀土加工生产的效率。When the method for detecting the degree of radioactive separation in lanthanum chloride designed by the present invention is applied to the rare earth processing and production process, since the detection time of the radioactive removal degree is greatly shortened, the efficiency of rare earth processing and production can be improved.
具体实施方式Detailed ways
为使本发明实施例的目的、技术方案和优点更加清楚，下面将对本发明实施例中的技术方案进行清楚、完整地描述。实施例中未注明具体条件者，按照常规条件或制造商建议的条件进行。所用试剂或仪器未注明生产厂商者，均为可以通过市售购买获得的常规产品。In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not indicated in the examples, it is carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used without the manufacturer's indication are conventional products that can be purchased from the market.
以下对本发明进行具体说明。The present invention will be specifically described below.
本发明实施例提供的检测氯化镧中放射性分离程度的方法，包括：采用皂化P507-煤油萃取剂对含有钙离子和锕离子的氯化镧混合溶液进行萃取分离使氯化镧混合溶液脱除钙离子和锕离子，测算钙离子的脱除率以评价氯化镧混合溶液的放射性脱除程度。The method for detecting the degree of radioactive separation in lanthanum chloride provided by the embodiment of the present invention includes: using a saponified P507-kerosene extractant to extract and separate a mixed solution of lanthanum chloride containing calcium ions and actinium ions to remove the mixed solution of lanthanum chloride. Calcium ion and actinium ion, the removal rate of calcium ion was calculated to evaluate the radioactive removal degree of lanthanum chloride mixed solution.
具体步骤如下：Specific steps are as follows:
S1、检测氯化镧混合溶液中钙离子的浓度C1，参与分离的氯化镧混合溶液的体积V1，计算得到氯化镧混合溶液中钙的量为W1。取用量与所述氯化镧混合溶液中镧离子之比为6～20L:1.5mol的皂化P507-煤油萃取剂备用，取用量与所述氯化镧混合溶液中镧离子之比为1～2L:1.5mol的反萃取剂备用。以上用量范围的萃取剂能够保证钙离子和放射性具有好的脱除效果。以上范围的反萃取剂能够保证脱除过程减少镧离子损失。S1. Detect the calcium ion concentration C 1 in the lanthanum chloride mixed solution, the volume V 1 of the lanthanum chloride mixed solution involved in the separation, and calculate the amount of calcium in the lanthanum chloride mixed solution as W 1 . The saponified P507-kerosene extractant with the ratio of the dosage to the lanthanum ions in the lanthanum chloride mixed solution is 6～20L:1.5mol for standby use, and the ratio of the dosage to the lanthanum ions in the lanthanum chloride mixed solution is 1～2L : 1.5mol of stripping agent for use. The extractant in the above dosage range can ensure good removal effect of calcium ions and radioactivity. The stripping agent in the above range can ensure that the removal process reduces the loss of lanthanum ions.
优选地，为提高萃取效果皂化P507-煤油萃取剂皂化率为20～50％，P507浓度为1.2～1.8mol/L。反萃取剂为氢离子浓度为4～5mol/L的酸液。优选地，反萃取剂为浓度4～5mol/L的盐酸。Preferably, in order to improve the extraction effect, the saponification rate of the saponified P507-kerosene extractant is 20-50%, and the concentration of P507 is 1.2-1.8 mol/L. The stripping agent is an acid solution with a hydrogen ion concentration of 4-5 mol/L. Preferably, the stripping agent is hydrochloric acid with a concentration of 4-5 mol/L.
S2、向含有钙离子和锕离子的氯化镧混合溶液中加入皂化P507-煤油萃取剂对氯化镧混合溶液进行萃取以分离脱除氯化镧混合溶液中的钙离子和锕离子，得到负载镧萃取剂。S2, adding saponified P507-kerosene extractant to the lanthanum chloride mixed solution containing calcium ions and actinium ions to extract the lanthanum chloride mixed solution to separate and remove calcium ions and actinium ions in the lanthanum chloride mixed solution to obtain a load Lanthanum extractant.
向含有钙离子和锕离子的氯化镧混合溶液中加入皂化率为20～50％的皂化P507-煤油萃取剂对氯化镧混合溶液进行萃取。优选地，为了提高萃取分离效率，进而提高检测分离程度的准确性，萃取方式为多级萃取。萃取是将钙离子和锕离子与镧离子分离，得到负载镧萃取剂。A saponified P507-kerosene extractant with a saponification rate of 20-50% is added to the lanthanum chloride mixed solution containing calcium ions and actinium ions to extract the lanthanum chloride mixed solution. Preferably, in order to improve the extraction and separation efficiency, thereby improving the accuracy of detecting the degree of separation, the extraction method is multi-stage extraction. Extraction is to separate calcium ions and actinium ions from lanthanum ions to obtain a loaded lanthanum extractant.
S3、向负载镧萃取剂中加入反萃取剂进行反萃取得到含有镧离子和钙离子的镧料液。S3, adding a stripping agent to the loaded lanthanum extractant for stripping to obtain a lanthanum feed solution containing lanthanum ions and calcium ions.
向负载镧萃取剂中加入浓度为4～5mol/L的盐酸对负载镧萃取剂进行反萃取。向负载镧萃取剂中加入盐酸，负载镧萃取剂中的镧离子以及没有被萃取分离的钙离子以及锕离子进入盐酸中，使得混合液分层，分离两层溶液，保留含有镧离子的溶液层得到镧料液。Hydrochloric acid with a concentration of 4-5 mol/L is added to the loaded lanthanum extractant to carry out back extraction of the loaded lanthanum extractant. Add hydrochloric acid to the loaded lanthanum extractant, and the lanthanum ions in the loaded lanthanum extractant, as well as the calcium ions and actinium ions that have not been extracted and separated, enter the hydrochloric acid, so that the mixed liquid is layered, the two layers of solutions are separated, and the solution layer containing the lanthanum ions is retained. A lanthanum feed solution is obtained.
通常加入的反萃取剂中可能会有钙离子杂质，为了避免钙离子杂质影响检测结果，提高检测结果的准确度，检测反萃取剂中钙离子的浓度C2，参与分离的反萃取剂的体积V2，计算得到反萃取剂中钙离子的含量W2，并记录，以作为后续计算钙离子脱除率时要用到的影响因素。Usually, there may be calcium ion impurities in the added back-extraction agent. In order to avoid calcium ion impurities from affecting the test results and improve the accuracy of the test results, the concentration C 2 of calcium ions in the back-extraction agent is detected, and the volume of the back-extraction agent involved in the separation is detected. V 2 , calculate the calcium ion content W 2 in the stripping agent, and record it as an influencing factor to be used in the subsequent calculation of the calcium ion removal rate.
S3、测定所述镧料液中钙离子的浓度C3、体积V3，计算镧料液中钙离子的含量W3；最后计算所述镧料液相对于所述氯化镧混合溶液钙离子的脱除率评价所述氯化镧混合溶液的放射性脱除率。S3, measure the concentration C 3 and volume V 3 of calcium ions in the lanthanum feed solution, calculate the content W 3 of calcium ions in the lanthanum feed solution; finally calculate the calcium ions in the lanthanum feed solution relative to the lanthanum chloride mixed solution The removal rate of the lanthanum chloride mixed solution was used to evaluate the radioactive removal rate of the lanthanum chloride mixed solution.
发明人通过研究，在P507萃取体系中，钙离子和锕离子的萃取效果，将两者的脱除效果进行对比，发现P507对227Ac和Ca2+萃取几乎完全相似，因此，可以通过检测萃取前后钙离子的脱除率来反映锕离子的脱除率。而氯化镧溶液中，锕离子是放射性的主要来源，因此，通过检测氯化镧溶液中钙离子的脱除率来评价放射性脱除程度。Through research, the inventors compared the extraction effects of calcium ions and actinium ions in the P507 extraction system, and compared the removal effects of the two, and found that the extraction of 227 Ac and Ca 2+ by P507 is almost completely similar. Therefore, it can be extracted by detecting The removal rate of calcium ions before and after reflects the removal rate of actinium ions. In lanthanum chloride solution, actinium ion is the main source of radioactivity, therefore, the degree of radioactive removal is evaluated by detecting the removal rate of calcium ion in lanthanum chloride solution.
因此，得到镧料液后检测镧料液中钙离子含量W3。通过W1、W2以及W3计算得到钙离子脱除率。钙离子脱除率为(W1+W2-W3)/W1。钙离子的脱除率与锕离子的脱除率相近，因此可以用于评价放射性脱除程度。Therefore, after obtaining the lanthanum feed solution, the calcium ion content W 3 in the lanthanum feed solution is detected. The calcium ion removal rate was calculated by W 1 , W 2 and W 3 . The calcium ion removal rate was (W 1 +W 2 -W 3 )/W 1 . The removal rate of calcium ions is similar to that of actinium ions, so it can be used to evaluate the degree of radioactive removal.
由于本发明通过检测氯化镧溶液中钙离子的脱除率来反映氯化镧溶液中放射性脱除程度。该方式可以使得放射性脱除程度在脱除操作完后立即计算得到。相较于现有的将溶液放置140天后再进行测量，大大缩短了氯化镧溶液放射性脱除程度的检测时间，可快速判断经放射性脱除处理的氯化镧溶液中放射性含量是否达标。其该方法简单方便，实用性强。Because the present invention reflects the degree of radioactive removal in the lanthanum chloride solution by detecting the removal rate of calcium ions in the lanthanum chloride solution. This method allows the degree of radioactive removal to be calculated immediately after the removal operation. Compared with the existing measurement after the solution is placed for 140 days, the detection time of the radioactive removal degree of the lanthanum chloride solution is greatly shortened, and it can be quickly judged whether the radioactive content in the radioactively removed lanthanum chloride solution reaches the standard. The method is simple, convenient and practical.
以下结合实施例对本发明的特征和性能作进一步的详细描述。The features and performances of the present invention will be further described in detail below in conjunction with the embodiments.
本发明各实施例提供所使用的氯化镧溶液均为La3+浓度为1.5mol/L，Ca2+浓度为1672mg/L。放置140天后测得总α浓度为40522Bq/L、总β浓度为11700Bq/L。The lanthanum chloride solutions used in the embodiments of the present invention are all with a La 3+ concentration of 1.5 mol/L and a Ca 2+ concentration of 1672 mg/L. After being placed for 140 days, the total α concentration was 40522Bq/L, and the total β concentration was 11700Bq/L.
实施例1Example 1
本实施例提供的检测氯化镧中放射性分离程度的方法，具体为：The method for detecting the degree of radioactive separation in lanthanum chloride provided by the present embodiment is specifically:
将体积为1L的氯化镧混合溶液采用体积为7L的P507浓度为1.5mol/L、皂化率为45％的P507-煤油萃取剂，经过10级萃取分离放射性元素后得到负载镧萃取剂，采用体积为1.05L的盐酸溶液作为反萃取剂对负载镧萃取剂进行反萃取，盐酸溶液中Ca2+浓度为20mg/L、HCl浓度为4.5mol/L，得到镧料液，镧料液中La3+浓度为1.4mol/L，Ca2+为903mg/L，计算得到初始氯化镧混合溶液到镧料液中钙的总脱除率为42％左右。根据钙的脱除率可知氯化镧混合溶液的放射性脱除程度在40％左右。The lanthanum chloride mixed solution with a volume of 1L adopts a P507-kerosene extractant with a volume of 7L and a P507 concentration of 1.5mol/L and a saponification rate of 45%. A hydrochloric acid solution with a volume of 1.05 L is used as a stripping agent to carry out stripping of the loaded lanthanum extractant. The concentration of 3+ is 1.4mol/L, and the Ca 2+ is 903mg/L. The total removal rate of calcium from the initial lanthanum chloride mixed solution to the lanthanum feed solution is calculated to be about 42%. According to the removal rate of calcium, it can be known that the radioactive removal degree of the mixed solution of lanthanum chloride is about 40%.
实施例2Example 2
本实施例提供的检测氯化镧中放射性分离程度的方法，具体为：The method for detecting the degree of radioactive separation in lanthanum chloride provided by the present embodiment is specifically:
将体积为1L的氯化镧混合溶液采用体积为20L的P507浓度为1.2mol/L、皂化率为20％的P507-煤油萃取剂，经过18级萃取分离放射性元素后得到负载镧萃取剂，采用体积为1.1L的盐酸溶液作为反萃取剂对负载镧萃取剂进行反萃取，盐酸溶液中Ca2+浓度为20mg/L、HCl浓度为4.5mol/L，得到镧料液，镧料液中La3+浓度为1.35mol/L，Ca2+为171mg/L。计算得到初始氯化镧混合溶液到镧料液中钙的总脱除率为90％左右。可知氯化镧混合溶液的放射性脱除程度达到大部分除去的程度。The lanthanum chloride mixed solution with a volume of 1L adopts P507-kerosene extractant with a volume of 20L and a P507 concentration of 1.2mol/L and a saponification rate of 20%. After 18-level extraction and separation of radioactive elements, a loaded lanthanum extractant is obtained. A hydrochloric acid solution with a volume of 1.1 L is used as a stripping agent to carry out stripping of the loaded lanthanum extractant. The concentration of 3+ was 1.35 mol/L, and the concentration of Ca 2+ was 171 mg/L. The total removal rate of calcium from the initial lanthanum chloride mixed solution to the lanthanum feed solution is calculated to be about 90%. It can be seen that the degree of radioactive removal of the lanthanum chloride mixed solution reaches the degree of removal of most of the radioactivity.
实施例3Example 3
本实施例提供的检测氯化镧中放射性分离程度的方法，具体为：The method for detecting the degree of radioactive separation in lanthanum chloride provided by the present embodiment is specifically:
将体积为1L的氯化镧混合溶液采用体积为6L的P507浓度为1.8mol/L、皂化率为36％的P507-煤油萃取剂，经过27萃取分离放射性元素后得到第一溶液，采用体积为1L的盐酸溶液作为反萃取剂对第一溶液进行反萃取，盐酸溶液中Ca2+浓度为20mg/L、HCl浓度为4.5mol/L，得到镧料液，镧料液中La3+浓度为1.48mol/L，Ca2+为58mg/L。计算得到初始氯化镧混合溶液到镧料液中钙的总脱除率为97％左右。根据钙的脱除率可知氯化镧混合溶液的放射性脱除程度达到几乎完全除去的程度。The lanthanum chloride mixed solution with a volume of 1L adopts a P507-kerosene extractant with a volume of 6L and a P507 concentration of 1.8mol/L and a saponification rate of 36%. After 27 extractions and separation of radioactive elements, the first solution is obtained, and the volume is 1L of hydrochloric acid solution is used as a stripping agent to carry out stripping of the first solution. In the hydrochloric acid solution, the concentration of Ca 2+ is 20 mg/L, and the concentration of HCl is 4.5 mol/L to obtain a lanthanum feed solution. In the lanthanum feed solution, the La concentration is: 1.48mol/L, Ca 2+ is 58mg/L. The total removal rate of calcium from the initial lanthanum chloride mixed solution to the lanthanum feed solution was calculated to be about 97%. According to the removal rate of calcium, it can be seen that the degree of radioactive removal of the lanthanum chloride mixed solution is almost completely removed.
实施例4Example 4
本实施例提供的检测氯化镧中放射性分离程度的方法，具体为：The method for detecting the degree of radioactive separation in lanthanum chloride provided by the present embodiment is specifically:
将体积为1L的氯化镧混合溶液采用体积为8L的P507浓度为1.5mol/L、皂化率为40％的P507-煤油萃取剂，经过30级萃取分离放射性元素后得到第一溶液，采用体积为1.8L的盐酸溶液作为反萃取剂对第一溶液进行反萃取，盐酸溶液中Ca2+浓度为20mg/L、HCl浓度为4.0mol/L，得到镧料液，镧料液中La3+浓度为0.8mol/L，Ca2+为34mg/L。计算得到初始氯化镧混合溶液到镧料液中钙的总脱除率为97.4％左右。根据钙的脱除率可知氯化镧混合溶液的放射性脱除程度达到几乎完全除去的程度。The lanthanum chloride mixed solution with a volume of 1L adopts a P507-kerosene extractant with a volume of 8L, the concentration of P507 is 1.5mol/L, and the saponification rate is 40%, and the first solution is obtained after 30-level extraction and separation of radioactive elements. 1.8L of hydrochloric acid solution is used as a stripping agent to carry out stripping of the first solution. In the hydrochloric acid solution, the Ca concentration is 20 mg/L, and the HCl concentration is 4.0 mol/L to obtain a lanthanum feed solution. In the lanthanum feed solution, La 3+ The concentration is 0.8mol/L, and the Ca 2+ is 34mg/L. The total removal rate of calcium from the initial lanthanum chloride mixed solution to the lanthanum feed solution was calculated to be about 97.4%. According to the removal rate of calcium, it can be seen that the degree of radioactive removal of the lanthanum chloride mixed solution is almost completely removed.
实施例5Example 5
本实施例提供的检测氯化镧中放射性分离程度的方法，具体为：The method for detecting the degree of radioactive separation in lanthanum chloride provided by the present embodiment is specifically:
将体积1L的氯化镧混合溶液采用体积为6L的P507浓度为1.5mol/L、皂化率为50％的P507-煤油萃取剂，经过35级萃取分离放射性元素后得到第一溶液，采用体积为1L的盐酸溶液作为反萃取剂对第一溶液进行反萃取，盐酸溶液中Ca2+浓度为20mg/L、HCl浓度为5mol/L，得到1L镧料液，镧料液中La3+浓度为1.47mol/L，Ca2+为42mg/L。计算得到初始氯化镧混合溶液到镧料液中钙的总脱除率为98％左右。根据钙的脱除率可知氯化镧混合溶液的放射性脱除程度达到98％左右程度。The lanthanum chloride mixed solution with a volume of 1L adopts a P507-kerosene extractant with a volume of 6L and a P507 concentration of 1.5mol/L and a saponification rate of 50%. After 35-level extraction and separation of radioactive elements, the first solution is obtained. 1L of hydrochloric acid solution is used as a stripping agent to carry out back extraction to the first solution. In the hydrochloric acid solution, the Ca concentration is 20 mg/L and the HCl concentration is 5 mol/L to obtain 1 L of lanthanum feed solution. In the lanthanum feed solution, the La concentration is: 1.47mol/L, Ca 2+ is 42mg/L. The total removal rate of calcium from the initial lanthanum chloride mixed solution to the lanthanum feed solution was calculated to be about 98%. According to the removal rate of calcium, it can be known that the degree of radioactive removal of the mixed solution of lanthanum chloride reaches about 98%.
实施例6Example 6
本实施例提供的检测氯化镧中放射性分离程度的方法，具体为：The method for detecting the degree of radioactive separation in lanthanum chloride provided by the present embodiment is specifically:
将体积1L的氯化镧混合溶液采用体积为10L的P507浓度为1.5mol/L、皂化率为36％的P507-煤油萃取剂，经过16级萃取分离放射性元素后得到第一溶液，采用体积为1.2L的盐酸溶液作为反萃取剂对第一溶液进行反萃取，盐酸溶液中Ca2+浓度为20mg/L、HCl浓度为4mol/L，得到1.2L镧料液，镧料液中La3+浓度为1.4mol/L，Ca2+为208mg/L。计算得到初始氯化镧混合溶液到镧料液中钙的总脱除率为86％左右。根据钙的脱除率可知氯化镧混合溶液的放射性脱除程度达到86％左右程度。The lanthanum chloride mixed solution with a volume of 1L adopts a P507-kerosene extractant with a volume of 10L and a P507 concentration of 1.5mol/L and a saponification rate of 36%, and the first solution is obtained after 16-stage extraction and separation of radioactive elements. 1.2L of hydrochloric acid solution is used as a stripping agent to carry out stripping of the first solution. In the hydrochloric acid solution, the Ca concentration is 20 mg/L and the HCl concentration is 4 mol/L to obtain 1.2 L of lanthanum feed solution. In the lanthanum feed solution, La 3+ The concentration is 1.4mol/L, and the Ca 2+ is 208mg/L. The total removal rate of calcium from the initial lanthanum chloride mixed solution to the lanthanum feed solution was calculated to be about 86%. According to the removal rate of calcium, it can be known that the radioactive removal degree of the mixed solution of lanthanum chloride reaches about 86%.
实验例Experimental example
将实施例1-4得到的镧料液放置140天，测溶液中总α浓度和总β浓度，并计算放射性脱除率，将实际放射性脱除结果与钙离子脱除率比较，并将结果记录至表1中。The lanthanum feed solution obtained in Example 1-4 was placed for 140 days, the total α concentration and total β concentration in the solution were measured, and the radioactive removal rate was calculated, the actual radioactive removal result was compared with the calcium ion removal rate, and the results were compared. Record in Table 1.
表1各实施例放射性脱除结果与钙离子脱除结果比较Table 1 Comparison of radioactive removal results and calcium ion removal results in each embodiment
通过表1能够看出，相同实施例钙离子的脱除率与放射性脱除率相接近，本发明实施例1-4提供的方法计算得到的钙离子脱除率可反映氯化镧溶液的放射性脱除程度。而从实施例1至实施例4能够看出，采用萃取剂脱除钙离子和锕离子，钙离子的脱除率略高于锕离子，而对钙离子的脱除率越高，与放射性脱除率值越接近，而萃取级数越高则脱除率越高，因此，要更准确通过钙离子的脱除率反映放射性的脱除率，在萃取过程中需要合理选择更多级数以保证钙离子有更高的萃取率，由此也能说明萃取级数越高则钙离子脱除率反映放射性脱除率的准确性也越高。It can be seen from Table 1 that the removal rate of calcium ions in the same embodiment is similar to the removal rate of radioactivity, and the removal rate of calcium ions calculated by the methods provided in Examples 1-4 of the present invention can reflect the radioactivity of the lanthanum chloride solution. degree of removal. From Examples 1 to 4, it can be seen that the removal rate of calcium ions and actinium ions is slightly higher than that of actinium ions by using the extractant, and the higher the removal rate of calcium ions, the higher The closer the removal rate value is, and the higher the extraction stage is, the higher the removal rate is. Therefore, in order to more accurately reflect the removal rate of radioactivity through the removal rate of calcium ions, it is necessary to choose more stages reasonably in the extraction process. To ensure that the calcium ion has a higher extraction rate, it can also be explained that the higher the extraction stage, the higher the accuracy of the calcium ion removal rate reflecting the radioactive removal rate.
综上所述，本发明提供的检测氯化镧中放射性分离程度的方法，由于本发明通过检测氯化镧溶液中钙离子的脱除率来反映氯化镧溶液中放射性脱除程度。该方式可以使得放射性脱除程度在脱除操作完后立即计算得到。相较于现有的将溶液放置140天后再进行测量，大大缩短了氯化镧溶液放射性脱除程度的检测时间，可快速判断经放射性脱除处理的氯化镧溶液中放射性含量是否达标。其该方法简单方便，实用性强。To sum up, the method for detecting the degree of radioactive separation in lanthanum chloride provided by the present invention reflects the degree of radioactive removal in the lanthanum chloride solution by detecting the removal rate of calcium ions in the lanthanum chloride solution. This method allows the degree of radioactive removal to be calculated immediately after the removal operation. Compared with the existing measurement after the solution is placed for 140 days, the detection time of the radioactive removal degree of the lanthanum chloride solution is greatly shortened, and it can be quickly judged whether the radioactive content in the radioactively removed lanthanum chloride solution reaches the standard. The method is simple, convenient and practical.
本发明提供的检测氯化镧中放射性分离程度的方法应用于稀土加工生产过程中时，由于大大缩短了放射性脱除程度检测时间，由此能够提高稀土加工生产的效率。When the method for detecting the degree of radioactive separation in lanthanum chloride provided by the present invention is applied to the rare earth processing and production process, since the detection time of the radioactive removal degree is greatly shortened, the efficiency of rare earth processing and production can be improved.
以上所述仅为本发明的优选实施例而已，并不用于限制本发明，对于本领域的技术人员来说，本发明可以有各种更改和变化。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.
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| CN85100148B (en) * | 1985-04-01 | 1987-08-26 | 清华大学 | Process method for producing fluorescent grade lanthanum oxide by method |
| CN1015436B (en) * | 1989-03-20 | 1992-02-12 | 甘肃稀土公司 | Method for separating si, ca, la from yb by extraction |
| US5147616A (en) * | 1991-10-03 | 1992-09-15 | The United States Of America As Represented By The United States Department Of Energy | Magnesium transport extraction of transuranium elements from LWR fuel |
| JP6409791B2 (en) * | 2016-02-05 | 2018-10-24 | 住友金属鉱山株式会社 | Scandium recovery method |
| CN106057265B (en) * | 2016-07-08 | 2017-11-17 | 广东省稀有金属研究所 | It is a kind of to remove radioactive method from the waste water of extraction lanthanum |
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