FTIR reflection spectra

Figure 1.7 FTIR reflection spectra of pyrite, pyrrohotite and chalcopyrite after 15 min treatment with 10 mol/L KEX solution at pH = 5 (Leppinen, 1990)...

The FTIR reflection spectra of ethyl xanthate, and iron ethyl xanthate were reported to show the following characteristic absorption bands of ethyl xanthate the stretching vibration bands of the C—O—C at 1100- 1172 cm and C==S at 1049 cm and 1008 cm". When dixanthogen was formed, the stretching vibration bands changed. The characteristic absorption bands are 1260 cm" , 1240 cm", 1020 cm" and 1105 cm". When iron ethyl xanthate was formed, the stretching vibration band of C=S shifted to 1029 cm" and 1005 cm" (Mielezarski, 1997 Leppinen, 1990). 

Figure 4.38 FTIR reflection spectra of ethyl xanthate adsorption on pyrrhotite (pH = 7.0, KEX 5 x 10 mol/L = 297 mV)...

Figure 4.41 presents the FTIR reflection spectra of ethyl xanthate adsorption on marmatite at different pH. The characteristic absorption peaks 1210, 1108, 1025 cm occurred. It has been reported that the characteristic absorption bands of dixanthogen are 1260, 1240, 1020 and 1105 cm and those bands of zinc xanthate are 1030, 1125 and 1212 cm (Mielezarski, 1986 Leppinen, 1990). It is derived from Fig.4.41 that there may exist the mixture of dixanthogen and zinc xanthate because both distinct peaks of dixanthogen and xanthate salt appeares in Fig. 4.41, which further confirms the results from the UV analysis in Fig. 4.36 and Fig. 4.37. It can also be seen from Fig. 4.41 that the intensity of the IR peaks is strong indicating the stronger adsorption of xanthate on marmatite accounting for its good floatability in weak pH media. When pH increased above 7, only a very weak peak appeared in the spectra indicating very weak or no adsorption of xanthate on marmatite accounting for its very poor floatability in alkaline pH media.

The FTIR reflection spectra of ethyl xanthate adsorption on jamesonite are shown in Fig. 4.42. It can be seen that the characteristic absorption bands of lead ethyl xanthate at 1020,1112 and 1206 cm" appeared on the surface of jamesonite, indicating the primary hydrophobic species on jamesonite surface to be lead ethyl xanthate. It is possible that antimony ethyl xanthate was formed on jamesonite surface simultaneity like lead ethyl xanthate. 

Figure 4.42 FTIR reflection spectra of jamesonite adsorption ethyl xanthate (pH = 7.0 KEX 5x10" mol/L Fh = 307 mV)...

The FTIR reflection spectra of DDTC (solid) and FeDs are shown in Fig. 4.45. Only at the 700-2000 cm region most of the important functional groups vibrations of diethyl dithiocarbamate are observed. From Fig. 4.44, it can be seen... 

FTIR reflection spectra of diethyl dithiocarbamate adsorption on pyrrhotite at pulp pH = 7.0 are demonstrated in Fig. 4.46. From Fig. 4.46, it can be seen that the characteristic absorption bands of dimmer of diethyl dithiocarbamate at 1468, 1425,1350,1269,1201,1139,1064,1005 and 968 cm appear on the surface of pyrrhotite, indicating the dominating hydrophobic species on pyrrhotite surface to be disulphide of dithiocarbamate. FiuTher, the effect of pulp potential on the adsorption of dithiocarbamate on pyrrhotite was examined and the results are presented in Fig. 4.47. It follows that at pH = 8.8 the dithiocarbamate adsorption on p)TThotite is mainly of disulphide independent of potential in die range of 297 - 687 mV due to the occurrence of almost the same disulphide characteristic band. However, the intensity of the IR signals changes at various potential values. It demonstrates the intensity of the IR signals of the characteristic peaks of thiouram disulphide and hence its adsorption on pyrrhotite decreases with the increase of the potential from 297 - 687 mV. At pH= 8.8, flotation recovery and... 

Figure 4.47 FTIR reflection spectra of DDTC adsorption on pyrrhotite at different pulp potential (pH = 8.8 DDTC 5x10" mol/L)...

The FTIR reflection spectra of marmatite in the absence of reagents and in the presence of CUSO4, butyl-xanthate, glycerin-xanthate are shown in Fig. 5.20. It... 

Fig. 50. In-situ FTIR reflectance spectra from a well-orderedPt(100) electrode (flame-annealed and cooled in Ar/H2 atmosphere), in 10 M K2SO4+O.5M KF/0.69 M HF (pH = 2.8). Sample potentials as indicated. Reference potential 0.030 V vs. a Pd/H2 electrode.

Fig. 57. In-situ FTIR reflectance spectra of adsorbed sulfate species on polycrystalline Pt in solutions of various pH values, as indicated.

In situ FTIR reflection spectra of a PAn I PB I Pt electrode are shown in Fig. 2 where the potential was stepped from 0 V vs Ag I AgCI to the cathodic side. The downward and upward bands correspond to the increase and decrease in concentration of adsorbed species on the electrode, respectively. The band observed at the wavenumber of 3600 to 3200 cm is attributable to the vibrational absorption of HjO. The negative-going peak at 2100 cm, which increases with stepping the potential to less noble side, means the electroreduction of PB to its reduced form (ES). A broad band appearing in the wavenumber region higher than 1600 cm is ascribed to the electronic absorption of PAn that is caused by free carriers (unpaired... 

Fig. 2 In situ FTIR reflection spectra of a PAn I PB I Pt electrode in Nj-sarurated 0.1M KCl solution. The electrode potential was stepped from 0 V (base) to various cathodic potentials as indicated (Ag I AgCl).

FTIR reflection spectra supply a fast and simple means for determination of foil thickness in polymer analysis (for QC purposes). The layer thickness of film t) can be determined from the number of the interference waves (V) over a range of wavelengths in case of a known refractive index (n) of the compound. 

Figure 13.5 Mid-infrared FTIR reflection spectra of individual biologic risk factors.

Figure 17. FTIR reflectance spectra of a silver electrode held at different potentials in sodium tetraborate (pH 9.2) containing 10" mol dm ethyl xanthate (a) and silver ethyl...

Fig. 4.8 FTIR reflectivity spectra of LUTiS2 as a function of lithium content...

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