scholarly journals Electrodialysis concentration of sulfuric acid

2021 ◽  
Vol 8 (1) ◽  
pp. 20218106
Author(s):  
S. A. Loza ◽  
N. A. Smyshlyaev ◽  
A. N. Korzhov ◽  
N. A. Romanyuk
Keyword(s):  
Sulfuric Acid ◽  
Steel Wire ◽  
Environmental Problems ◽  
Production Cycle ◽  
Anion Exchange Membranes ◽  
Resource Saving ◽  
Urgent Task ◽  
Slaked Lime ◽  
Electrodialysis Cell ◽  
Heavy Metal Salts

An urgent task is the development of new resource-saving technologies for deep processing of wastes from the hydrometallurgical industry for the purpose of their reuse. Membrane technologies make it possible to create closed technological cycles with the reuse of recovered components in production, which allows solving many environmental problems. At the Abinsk Electric Steel Works Ltd. (Russia), during the production of copper-coated steel wire, a large amount of waste containing sulfuric acid and heavy metal salts is generated. The chemical treatment of such effluents with slaked lime and alkali produces a large amount of sludge, which causes environmental problems and leads to the irreversible loss of sulfuric acid. The problem of separating acids and salts can be solved using diffusion dialysis through anion-exchange membranes, however, to return the acid to the production cycle, the purified acid must be additionally concentrated. In this work, we studied the process of electrodialysis concentration of sulfuric acid using heterogeneous ion-exchange membranes Ralex® CMHPP and Ralex® AMHPP (manufactured by MEGA a.s., Czech Republic) which have a polypropylene reinforcing mesh resistant to acids. The main parameters of the electrodialysis concentration process have been determined – the dependence of the concentration of the regenerated sulfuric acid on the concentration at the inlet to the electrodialysis cell and on the current density, as well as the energy consumption for the process. It is shown that with the help of electrodialysis concentration it is possible to obtain sulfuric acid with a concentration of up to 180 g/L, which makes it possible to return it to the production cycle.

Cation and Anion Exchange Membranes Prepared by Radiation-Induced Graft Polymerization for Application in Electrodialysis

2014 ◽  
Vol 881-883 ◽  
pp. 1157-1160 ◽  
Author(s):  
Jin Hua Chen ◽  
Asano Masaharu ◽  
Yasunari Maekawa
Keyword(s):  
Aqueous Solution ◽  
Anion Exchange ◽  
Graft Polymerization ◽  
Exchange Capacity ◽  
Anion Exchange Membranes ◽  
Ion Exchange Capacity ◽  
Electrodialysis Cell ◽  
Radiation Induced ◽  
Poly Ethylene ◽  
Percent Removal

Cation and anion exchange membranes were prepared by radiation-induced graft polymerization of ethyl styrenesulfonate and chloromethyl styrene, respectively, onto poly (ethylene-alt-tetrafluoroethylene) (ETFE) films, followed by hydrolysis in the former case and quaternization in the latter case. The degree of grafting as well as the ion exchange capacity (IEC) and the conductivity of the prepared membranes were investigated. Furthermore, the cation and anion exchange membranes were tested in an electrodialysis cell using CsNO3 aqueous solution in the dilute compartment. It was found that the high-IEC membranes enhanced the electrodialysis speed, while the low-IEC membranes showed the high percent removal.

PERSPECTIVE OF USE OF SUGAR BEET PRODUCTION WASTE - MOLASSES IN TECHNOLOGY OF RUBBER ISOLATION FROM LATEX

1970 ◽  
Vol 61 (11) ◽  
Author(s):  
Nadezhda S. Nikulina ◽  
Victor N. Verezhnikov ◽  
Sergey S. Nikulin ◽  
Marya A. Provotorova ◽  
Inna N. Pugacheva
Keyword(s):  
Sulfuric Acid ◽  
New Technologies ◽  
Raw Materials ◽  
Low Cost ◽  
Production Waste ◽  
Urgent Task ◽  
Softened Water ◽  
Treatment Facilities ◽  
Butadiene Styrene

At present, much attention is paid to improving the production of synthetic rubbers. The introduction of new technologies to increase the productivity of the process, more fully and rationally use valuable hydrocarbon raw materials, reduce environmental pollution and improve the quality of the products is an important and urgent task. Equally important in this case is the selection of new coagulating agents used in the technology of rubber release from latex. The main requirements for coagulating agents used in the technology of rubber release from latex are: availability, low cost, non-toxicity, ease of cleaning of sewage coming to treatment facilities from them. The possibility of application of the beet-sugar production waste - molasses for beet-lean depletion - in the technology of producing butadiene-styrene rubber SKS-30 ARC has been studied. A feature of the behavior of molasses, as a coagulating agent, is shown when isolating rubber from latex. It has been established that the consumption of molasses in the isolation of butadiene-styrene rubber from latex is closely related to the consumption of acidifying agent - sulfuric acid. The higher the molasses input for coagulation, the higher the consumption of sulfuric acid to maintain the pH of the medium at the required level. The temperature of the process did not have a significant effect on the completeness of the release of rubber from latex. The extracted crumb of rubber was separated from the aqueous phase (sulfur), washed with warm softened water and dried. On the basis of the rubber obtained, rubber mixtures were prepared using standard components and vulcanized. Rubbers obtained on the basis of rubber SKS-30 ARC, in their indicators meet the requirements.

Building Ecomaterials Based on Secondary Raw Material

2018 ◽  
Vol 284 ◽  
pp. 916-921
Author(s):  
Mihail Gerasimovich Bruyako ◽  
L. Grigoryeva
Keyword(s):  
Building Materials ◽  
Raw Materials ◽  
Raw Material ◽  
Household Waste ◽  
Environmental Damage ◽  
Moisture Resistance ◽  
Pressing Pressure ◽  
Resource Saving ◽  
Urgent Task ◽  
Environmentally Safe

Mineral raw natural resources are not unlimited. Preservation of such non-renewable resources is the most urgent task of mankind. The development of non-waste technologies, the integrated use of secondary raw materials, which simultaneously reduces environmental damage - one of the ways to solve environmental problems. Utilization of wastes makes it possible to solve issues of environmental protection as well as resource saving. In the light of environmental requirements, building materials based on recycled materials, including cellulose-containing solid waste, have significant advantages over other traditional materials. Development of technology for obtaining new effective environmentally safe composite highly filled materials based on cellulose-containing solid household waste for the production of construction products is a rational link in solving the general problem of improving the environmental situation. In the article there are three main ways of combining gypsum binder with cellulose-containing solid household waste. Investigations were carried out on the effect of changing the ratio of cardboard / gypsum binder, specific pressing pressure, sequence of combination of components on the properties of the final product. The strength of the material was determined from the values of the flexural strength, the compression to complete destruction of the sample, and at 10% deformation. Studies have been carried out to increase moisture resistance. The results showed that the most optimal way of combining is the 2 way. The increase in moisture resistance is significantly enhanced by the action of organosilicon hydrophobisers.

scholarly journals Development of the smelting technology of complex aluminum-chrome-silicon-containing ASC alloy from substandard raw materials

2018 ◽  
Vol 61 (9) ◽  
pp. 714-720
Author(s):  
A. S. Orlov ◽  
A. Z. Isagulov ◽  
O. R. Sariev ◽  
M. Zh. Tolymbekov
Keyword(s):  
Raw Materials ◽  
Experimental Studies ◽  
Coal Ash ◽  
Furnace Operation ◽  
Reducing Agent ◽  
Raw Material ◽  
Production Cycle ◽  
Resource Saving ◽  
Complex Alloy ◽  
The Rich

Scientists of the Chemical-Metallurgical Institute named after Zh.  Abishev develop new types of highly effective alloys based on resource-saving technologies that allow the complex processing of natural and technogenic raw materials, such as carbonaceous waste, chrome ore fines, etc. Therefore, it has led to the creation of a onestage, slag-free and non-waste technology with the maximum use of all useful charge components. With disappearance of rich ore reserves, as well as the expansion of demand for raw materials and the development of technology, the rich ores are replaced by poorer and substandard ones that require new methods of processing. The maximum use of raw materials and industrial waste, if this is economically justified, is one of the basic requirements for the technology. This task is closely intertwined, and in many cases coincides with another task – the development of integrated methods of raw materials processing, which, in the general production cycle, allows using, if possible, all useful elements of raw materials. The main objective of the study is to find ways to improve the use of sub-standard chrome ore. As a reducing agent in the electrothermal smelting of the ACS alloy, instead of expensive coke, without which no process of carbothermic smelting is required, a cheap high-ash Borly coal was used. The coal ash, which mainly consists of silica and alumina, is an additional source of silicon and aluminum in the alloy. This technology will be simple and allows regarding substandard chromium ore as a complex metallurgical raw material, since not only chrome is used, but also the components of the waste rock – silicon and aluminum. As a result of the complete reduction of all charge oxides, this technology will make it possible to obtain a complex alloy of ACS with an approximate chemical composition: 39  –  43  % of chromium, 23  –  27  % of silicon, 7  –  10  % of aluminum. The transition of the main components of the charge to the alloy will be: 82  –  85  % of chromium, 68  –  70  % of silicon, 59  –  60  % of aluminum. In this paper, the results of experimental studies on the production of a complex alloy of ACS (aluminum-chromium-silicon) from high-ash coals of the Borly deposit and chrome ore minerals of the Donskoi GOK are presented. The course of furnace operation is described with a lack, excess, and also the calculated amount of the reducing agent. The ways of eliminating the upset in furnace operation are shown.

scholarly journals Investigating the Lifetime of Fibre Ropes

2020 ◽  
Vol 1 ◽  
pp. 1-8
Author(s):  
Annett Schmieder ◽  
Markus Golder
Keyword(s):  
Energy Efficient ◽  
Breaking Strength ◽  
Steel Wire ◽  
High Strength ◽  
New Materials ◽  
Resource Saving ◽  
Dead Weight ◽  
Wire Ropes ◽  
Machine Elements ◽  
Level Of Knowledge

Steel wire ropes have established as transmission, connection and safety elements in transporters such as cranes and elevators, due to their high breaking strength and operational safety as well as out of many years of experience. However, steel wire ropes have disadvantages such as high dead weight, high bending stiffness and sensitivity to corrosion. Increasing requirements on the energy-efficient and resource-saving operation of technical systems demand new materials, technologies and processes. As a result, textile machine elements like HM-HT fibre ropes (high modulus, high tenacity) come into focus of considerations. The aim of the research is to expand the level of knowledge with regard to the state of wear and aging. Another aim is to find out the influencing factors on the lifetime, discard criteria of high-strength fibre ropes and to derive methods for lifetime detection.

Effect of modes of patenting carbon wire on its properties

2020 ◽  
pp. 44-48
Author(s):  
I. Yu. Mezin ◽  
◽  
A. S. Limarev ◽  
V. M. Salganik ◽  
I. G. Gun ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Content ◽  
Steel Wire ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Strength Properties ◽  
Urgent Task ◽  
Starting Point ◽  
Steel Grades ◽  
The Wire

To increase the competitiveness of carbon steel grades in enterprises, it is necessary to constantly improve the production process. The manufacture of high-strength wire is an urgent area for the enterprises of the hardware industry. One of the most important indicators determining the quality of the wire is the achievement of the specified physical and mechanical properties and microstructure. To this end, the wire is subjected to patenting, which is carried out in special units. To achieve the desired result during patenting, it is necessary to choose and observe the correct regimes depending on the diameter of the wire being processed and the chemical composition of the steel. When developing the modes, it is taken into account that martensite and a significant amount of excess ferrite along the grain boundaries are not allowed in the structure of patented steel. In the course of the work, an analysis was made of the most common carbon wire patenting modes in production, statistical dependences of the designated heating modes of the wire billet and cooling medium on the parameters of the steel wire, namely, its diameter and carbon content in steel, were obtained. An assessment of its strength properties is also carried out. According to the results of the analysis of patenting modes, it was found that certain difficulties arise when mastering the process of patenting steel wires of thick diameters and a carbon content of more than 0.8. Therefore, the solution of issues related to the course of these processes seems to be an urgent task. The results of the studies show the possibility of ensuring the necessary level of mechanical properties of steel in billets of thick diameters during the implementation of the process using lead melt. The data obtained can serve as a starting point for industrial testing and the prospective development of patenting processes.

Problems of Waste Recovery and Socio-Ecological Inequality

2019 ◽  
Vol 23 (5) ◽  
pp. 52-55 ◽  
Author(s):  
I.A. Vershinina ◽  
T.S. Martynenko
Keyword(s):  
Global Economy ◽  
Environmental Problems ◽  
Environmental Consciousness ◽  
Resource Saving ◽  
Waste Recovery ◽  
Ecological Culture ◽  
Treatment And Disposal

On the example of various approaches to waste recovery and recycling of garbage existing in different countries, the role of ecological culture in solving environmental problems is analyzed. Based on the analysis of problems associated with landfills, features of the Russian environmental consciousness are presented. The importance of the transition from the widespread burial of waste to their treatment and disposal on the basis of resource-saving technologies that are effectively used in the global economy is emphasized.

Comparison of the applicability of selected anion-exchange membranes for production of sulfuric acid by electro-electrodialysis

2017 ◽  
Vol 64 ◽  
pp. 223-227 ◽  
Author(s):  
Hanna Jaroszek ◽  
Wojciech Mikołajczak ◽  
Mariusz Nowak ◽  
Bożenna Pisarska
Keyword(s):  
Sulfuric Acid ◽  
Anion Exchange ◽  
Anion Exchange Membranes

Imidazole-functionalized polyketone-based polyelectrolyte with efficient ionic channels and superwettability for alkaline polyelectrolyte fuel cell and multiple liquid purification

2021 ◽  
Author(s):  
Yi-cun Zhou ◽  
Zheng-Min Zhang ◽  
Ling Zhou ◽  
Rui-Ying Bao ◽  
Zheng-Ying Liu ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Ionic Conductivity ◽  
Anion Exchange ◽  
Ionic Channels ◽  
Environmental Problems ◽  
Anion Exchange Membranes ◽  
Core Component

Anion exchange membranes (AEMs) have received widespread attention as a core component in devices to solve energy and environmental problems. However, current AEMs cannot satisfy the requirement of ionic conductivity...

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