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Heat electrolytic cells

The ammonium hydrogensulphate is returned to the electrolytic cell. A process such as this yields an aqueous solution containing about 30% hydrogen peroxide. The solution can be further concentrated, yielding ultimately pure hydrogen peroxide, by fractional distillation but the heating of concentrated hydrogen peroxide solutions requires care (see below). [Pg.278]

A Perkin-Elmer 5000 AAS was used, with an electrically heated quartz tube atomizer. The electrolyte is continuously conveyed by peristaltic pump. The sample solution is introduced into the loop and transported to the electrochemical cell. A constant current is applied to the electrolytic cell. The gaseous reaction products, hydrides and hydrogen, fonued at the cathode, are flowed out of the cell with the carrier stream of argon and separated from the solution in a gas-liquid separator. The hydrides are transported to an electrically heated quartz tube with argon and determined under operating conditions for hydride fonuing elements by AAS. [Pg.135]

An electrochemical cell is a device by means of which the enthalpy (or heat content) of a spontaneous chemical reaction is converted into electrical energy conversely, an electrolytic cell is a device in which electrical energy is used to bring about a chemical change with a consequent increase in the enthalpy of the system. Both types of cells are characterised by the fact that during their operation charge transfer takes place at one electrode in a direction that leads to the oxidation of either the electrode or of a species in solution, whilst the converse process of reduction occurs at the other electrode. [Pg.77]

Electrolytic zinc smelters contain up to several hundred cells. A portion of the electrical energy is converted into heat, which increases the temperature of the electrolyte. Electrolytic cells operate at temperature ranges from 30 to 35°C (86 to 95°F) at atmospheric pressure. During electrowinning a portion of the electrolyte passes through cooling towers to decrease its temperature and to evaporate the water it collects during the process. [Pg.92]

The cell construction provides (i) a uniform internal distribution of up to four separate electrolytes, (ii) cooling and heating facilities (useful temperature range ca. - 40 °C up to -I- 250 °C), (iii) gas supply, and (iv) different turbulent promotors to improve transport performances. The versatility of off-the-shelf cells, paired with increasing experience of integrating electrolytic cells into industrial processes thus reduces the obstacles and risks for the scale-up. Furthermore, electrochemical units lend themselves well to modular construction, thus CPI plant expansion is a chance for this new technique. [Pg.137]

Early separators used in NiCd cells for space applications consisted of materials as ordinary as Whatman filter paper and eventually nonwoven nylon felt (Pellon 2505). Pellon 2505 was more stable than cellulosic separators, but it too had stability limitations. In the late 1960s and early 1970s, nonwoven polypropylene saw limited use in NiCd cells. The PP separators were quite useful where sterilization (heating the cell to 135 °C) was required.The major difficulty with nonwoven polypropylene was that it was only marginally wet-table. and the amount of electrolyte that can be placed in the cell was limited. [Pg.211]

Coke which is low in sulfur and metal content is valued as a fuel, as a raw material for the manufacture of electrodes, and in graphite production. To produce high-purity coke, all traces of volatile matter must be removed from coke. A calcination process is utilized for this purpose. This process requires the coke to be heated to temperatures of 2,000°F (1,093.3°C) or higher. The pure coke is valued as raw material for the manufacture of electrolytic cell anodes and as a pure carbon source. [Pg.24]

A positive standard cell potential tells you that the cathode is at a higher potential than the anode, and the reaction is therefore spontaneous. What do you do with a cell that has a negative " gii Electrochemical cells that rely on such nonspontaneous reactions cire called electrolytic cells. The redox reactions in electroljdic cells rely on a process called electrolysis. These reactions require that a current be passed through the solution, forcing it to split into components that then fuel the redox reaction. Such cells are created by applying a current source, such as a battery, to electrodes placed in a solution of molten salt, or salt heated until it melts. This splits the ions that make up the salt. [Pg.266]

Copper used in electrical wires and circuits should be very pure. Crude copper is refined electrochemically by using electrolytic cells. Impure copper is given a positive charge (anode), and pure copper is given a negative charge (cathode). 166 Heat, Chemical Kinetics and Eiectrochemistry... [Pg.166]

The heat and entropy associated with the above reaction implied by the temperature dependence of the critical oxygen activity were —46 kcal mol 02 1 (-192 kJ mol 02 ) and -45 kcal K-1 mol O 1 (-188 kJ K-1 mol 02- ) in close agreement with the results of Berry.81 Oxygen adsorption and oxide formation on platinum have also been studied using exchange currents in a solid electrolyte cell.82... [Pg.24]

No harm is done when the electrolyte is allowed to solidify in the generator but when it is again melted, the burners should be allowed to melt the top part of the solid before the bottom is heated. Repeated violation of this precaution might rupture the apparatus, because the density of the solid is greater than that of the liquid. A circular gas burner which directs flames inwardly may be adjusted to heat the cell in the desired manner. No heating is necessary while electrolysis is in progress, unless a small current is used. [Pg.145]


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