Development of Obtaining Technology of LiAsF6 and LiPF6
Development of Obtaining Technology of Lithium Hexafluoroarsenate and Lithium Hexafluorophosphate - Components of Organic Electrolytes for Chemical Current Sources
Tech Area / Field
- CHE-IND/Industrial Chemistry and Chemical Process Engineering/Chemistry
- NNE-BCM/Batteries and Components/Non-Nuclear Energy
8 Project completed
Senior Project Manager
State Research Institute of Organic Chemistry and Technology, Russia, Moscow
- US Army's Edgewood Chemical Biological Center, USA, MD, Aberdeen Proving Ground
Project summaryProblems of non-nuclear energetics on the urgency are among the first in the world. The important direction is creation of new effective chemical current sources (CCS). In this area interest to lithium CCS, which surpass traditional systems in the characteristics, is still high.
Solutions of lithium salts with large single-charged anions in aprotic mediums are the most widespread and perspective electrolytes in lithium CCS. Lithium hexafluorophosphate LiPF6 and lithium hexafluoroarsenate LiAsF6 are two salts, which are considered now as the best for use in composition of complex electrolytes in lithium CCS.
Synthesis of the specified salts is described in significant number of patents of leading, on a level of development of the chemical industry, countries of the world. These compounds are offered by a number of firms to sale as preparations of a various degree of purity. However, the achieved level of development of the given direction is obviously insufficient. Therefore, a number of the important patents on synthesis and clearing of a lithium hexafluorophosphate and a lithium hexafluoroarsenate has appeared literally recently. Complexity of a problem consists in necessity of obtaining of very pure substances, waterless and not containing acids and metals in appreciable quantities (it is an obligatory condition for an opportunity of their use in composition of electrolytes). At the same time initial compounds and intermediate products for synthesis of target compounds are dangerous to an environment (ecotoxicants) and corrosive, that creates a number of engineering, sanitary and environmental problems.
Therefore, development of advanced, more simple and safe in the ecological relation, methods of synthesis of the given salts and their clearing, suitable for technological use, and technological study of the most effective methods is the actual problem having the important applied significance.
The purposes of the project:
– the analysis of the information on methods of obtaining of a lithium hexafluorophosphate and a lithium hexafluoroarsenate and allocation from all host of methods, suitable for technological study;
– a choice of a method for development of technology (for each salt);
– perfection and optimization of the chosen methods of synthesis of above-stated electrolytic salts providing a necessary category of production quality (at a level of high purity substances);
– the decision of questions of ecological safety at realization of the given processes in industrial scale.
The highly skilled staff of SITOS, earlier engaging in development of the chemical weapon, is involved in work. They save up wide experience of realization of researches in the field of synthesis, technologies of obtaining and studying of properties of various compounds of phosphorus, fluorine and arsenic - that is, practically, in the same area of industrial chemistry to which the given project concerns.
Expected results and their application.
The offered development concerns to applied researches. Realization of the specified works should lead to following results:
– the technological estimation of the basic known methods of synthesis of the specified salts will be carried out and will be chosen optimum, suitable for realization in sufficiently large industrial scale;
– the chosen methods of synthesis of salts will be comprehensively investigated in the technological plan with distribution on each salt of the complete set of documents (the initial data), allowing to proceed further to designing of industrial productions;
– thus, result of work will be creation of scientific bases of obtaining technologies of lithium hexafluorophosphate LiPF6 and lithium hexafluoroarsenate LiAsF6.
Meeting ISTC goals and objectives.
The given project answers basic purpose of ISTC - switching of scientists of SITOS, connected before with development of the chemical weapon, to performance of the applied research work serving to peace and practically important purposes. Work within the limits of the given project will result also in integration of scientists of SITOS to international scientific community. Applied researches, which may be realized in SITOS by creation of installations on release of the specified salts, will be maintained. It will promote transition of the enterprise to the market economy (already now there are applications of the western firms for purchase of given production).Scope of Activities.
The project is expected for 2 years. For this time the necessary big volume of applied research works, which consists of 9 tasks, should be executed. They are:
1. Gathering the information on methods of obtaining of target substances and the analysis of the collected material with the purpose of allocation from all data set of methods, suitable for technological study.
2. Experimental approbation of the selected methods of obtaining of salts and a choice of a method for development of technology.
3. Perfection and optimization of the chosen method of synthesis of a target product (for each salt).
4. Development of hardware design and the basic flow diagram of target product obtaining process (for each salt).
5. Definition of necessary physicochemical and thermal characteristics of the substances participating in process, including initial, intermediate and target compounds.
6. System engineering of the analytical control of process, including development of techniques of quantitative definition of the contents of microimpurity in target products.
7. Recycling of toxic waste products formed in production, and development of the actions providing preservation of the environment at realization of process in industrial scale.
8. Development of necessary actions for the safety precautions and industrial sanitary at realization of process.
9. Formation of complete sets of the documentation (the initial data on designing), containing the systematized results of the executed work.
Technical approach and methodology.
The methodology includes the following:
– the direction of technological works will be based on the generalized world experience of the research works executed in the given area up to present time;
– a choice of a method for technological study and its subsequent optimization will be based on the generalized technical and economic criteria which are taking into account both technical (an output, quality of turning out products, parameters of process etc.), and economic parameters (account factors on raw material and comparative cost of various kinds of raw material, power expenses, specific consumption of materials etc.);
– in a basis of the developed actions, providing preservation of the environment, the principle of minimal ecological prejudice to the nature and the person will be fixed.
The technical approach includes the following:
– improvement of processes on the standard laboratory process equipment;
– realization of processes in the non-standard specially made equipment from non-corrodible materials;
– realization of the chemical and tool analysis of intermediates, reactive mixes and target substances;
– realization of instrumental physicochemical measurements;
– toxicological researches on animals by standard techniques;
– calculations with use of the ready and specially created programs on personal computers.