ศักย์เทอร์มอลคร่อมแผ่นเยื่อแลกเปลี่ยนไอออนในสารละลายเกลือคลอไรด์ / มาลี ธนะสาร = Thermal potential across ion exchange in chloride salt solution / Malee Tanasan
In this research, the study on thermal membrane potential across ion exchange membrane CR61 AZL389 separating two solutions which are at different temperatures were carried. out to be compared with the theory of non-isothermal Systems. The solutions used in this experiment are lithium chloride, sodium chloride, potassium chloride, magnesium chloride and calcium chloride at con centration of 0.001, 0.005, 0.01, 0.05 and 0.1 mole per liter for each solution. Silver-silver chloride electrodes were used to measure the thermal membrane potential while the temperature difference between two solutions was read by a thermocouple. The range of temperature difference is in order of 10 celcius while the temperature at one compartment is kept constant at room temperature. In the first part of this research, all data were recorded on a graph-recorder and analyzed by an 8-bits micro-computer. In the final part, both thermal potential and temperature signals were processed and linked with 8-bits micro-computer by the constructed interface circuit, which is very helpful in averaging the huge amount of data pairs. The experimental results show that the thermal membrane potential is linear dependent with temperature difference. The potential temperature difference ratio is linearly related with logarithermic value of salt activity The mentioned results are deviated from theoretical values cue to no ideality of ion exchange membrane. Namely, the cation transport numbers are less than unity.