Catalytic infrared drying

Recently, a new method of flameless catalytic infrared (CIR) drying has been developed, in which energy is generated by catalyzing natural gas or propane conversion with a platinum catalyst. Relatively few reports are available regarding CIR dehydration. 

Infrared Procedures. Acidity Measurements. Zeolites treated as for catalytic experiments (heating in a stream of dry air and equilibration with H20 vapor at room temperature) were compressed at 1000 kg/cm2. The resulting disks (5 mg/cm2) were mounted in a quartz sample holder which was introduced into an IR cell as previously described (18). They were heated slowly under vacuum (the temperature was raised stepwise up to 450° in 5 hours). At 450°C, 02 was admitted, and the cell, connected to a liquid nitrogen trap, was maintained at this temperature for 4-5 hours. Finally the wafers were evacuated overnight at 450° C. The vapor of thoroughly dried pyridine was allowed to equilibrate with the wafer at room temperature. Afterwards, the pyridine was desorbed at a series of increasing temperatures for 15 hours each time. 

Infrared spectra of pyridine adsorbed on kaolinite indicated that the dry clay (110°C) contained both Brtfnsted and Lewis acid sites (235). At 1% water content only protonic acid sites were observed. It was not possible to assign the polymerization activity to either type of acid site, since both were present on samples which were catalytically active. 

Titanium sulfate supported on zirconia catalysts were prepared by drying of powdered Zr(OH)4 with titanium sulfate aqueous solution followed by calcining in air at high temperature. The characterization of prepared catalysts was performed using Fourier transform infrared (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and by the measurement of surface area. The addition of titanium sulfate to zirconia shifted the phase transition of ZrOa from amorphous to tetragonal to higher temperature because of the interaction between titanium sulfate and zirconia. The catalytic activities for both reactions, 2-propanol dehydration and cumene dealkylation were correlated with the acidity of catalysts measured by ammonia chemisorption method. 

The dried polymer is analyzed for sulfur the inherent viscosities are determined in dimethyl sulfoxide. Unsaturation is determined by catalytic hydrogenation in tetramethylene sulfone and examination of the infrared absorption in... 

Combined analyses of DOC and DON are performed in catalytic HTO systems, where the combustion of the water samples takes place generally at —680°C in the presence of Pt-Al203 catalyst. After the gas mixture containing the combustion products (CO2, NO, H2O, etc.) is dried, it passes in series through a nondispersive infrared detector (NDIR), for determination of DOC as CO2, and through a chemiluminescent detector, for determination of DON as NO2 [57,84,148,149,155]. Merriam et al. [146] proposed a catalytic oxidation at 680°C with Pt-A Oa and CuO as catalysts for the analysis of only TDN in soil solutions and throughfall, as alternative choice to noncatalytic HTO and PO methods. 

Initial attempts at producing a catalytic chitosan film were carried out using a glass substrate and an Al substrate. A lwt% solution of chitosan was made up in 1% aqueous acetic acid and was cast onto the substrates and allowed to dry, initially at room temperature, and then at 60°C. Clear films were successfully formed in both cases, and were moderately resistant to abrasion, and completely resistant to soaking in hot solvents (water, ethanol, toluene, THF at 50 C for 72h had no effect on the film). Diffuse reflection infrared studies indicated the presence of chitosan on the substrates before and after immersion in solvents. 

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