DTA-EGD-GC on-line coupled simultaneous

For extended applications, a DTA/DSC-EGD-GC on-line coupled simultaneous technique and relevant apparatus were established in the 1980s [63]. The CDR-1 E>SC analyzer was replaced by the Model CRY-1 DTA (ambient temperature ca 1200 C) for the purpose of high-temperature measurements. The scheme of the DTA-EGD-GC on-line coupled simultaneous apparatus is shown in Figure 2.37. DTA and a EGD-GC... 

The functioning of the DTA-EGD-GC on-line coupled simultaneous apparatus is as follows ... 

During the last two decades, the DTA-EGD-GC on-line coupled simultaneous apparatus has been applied in the following fields solid catalysts [77-79], anti-oxidation additives in petroleum [80], thermal characteristics of coal [81-83], mineralogy [60, 84-87], organometallic chemistry [88-90], polymer chemistry [91], pharmaceutical chemistry [92], environmental protection chemistry and the thermal behavior of all kinds of chemical compounds [62, 63]. Numerous DTA-EGD-GC curves are shown in Chapter 13. 

Evaluation of Catalysts in the Solid State by the DTA-EGD-GC On-line Coupled Simultaneous Technique... 

The DTA-EGD-GC on-line coupled simultaneous technique and associated equipment have been in use since the 1980s [1-3]. The principles and applications in various areas of science of the DTA-EGD-GC technique were outlined in Part I, Sections 2.4.3 and 5.3.1. 

The DTA-EGD-GC on-line coupled simultaneous technique provides a microscale experimental method that is precise and rapid for the investigation of the reaction processes involved in the thermal decomposition of samples. The variations of the composition of reaction gases evolved can be traced and the mechanism of gas-solid phase and gas-gas phase thermal reactions in an inert gas or reactant gas can be studied. 

An analytical scheme for the TA-EGD-EGA coupled simultaneous technique is shown in Figure 2.32. The evolved gas from TA (DTA/DSC or TG) is introduced into the EGA system after passing through the EGD system. The evolved gas is directly introduced to a thermal conductivity detector (TCD), avoiding second reactions. Two methods are used for the TA and EGA coupled simultaneous technique (1) on-line coupled simultaneous technique in series and (2) off-line combined method. In technique (1), TA is connected serially with a Gas chromatograph (GC) [61-65], mass spectrometer (MS) [57, 64, 65], Fourier transform infrared (FTIR) spectrometer [66, 67], non-dispersive IR (NDIR) spectrometer [68, 69] or thermo-gas-titrimetric... 

The DTA/DSC-EGD coupled simultaneous technique and relevant equipment have been investigated since 1979 [62, 74, 75]. The Model CDR-1 power compensation DSC analyzer (ambient temperature ca 720 C) was developed by the Tian Ping Instrumental Factory (Shanghai, China). The EGD detector is a thermal conductivity detector (TCD) in the GC analyzer. The CDR-1 DSC analyzer coupled with GC was constructed using a specially designed gas conduit. A schematic diagram of the on-line coupled simultaneous DTA/DSC-EGD apparatus is shown in Figure 2.33. 

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