The reaction products of gaseous TiCl4 with ammonia were TiCl4·5NH3 at 200 °C, TiCl4·5NH3, TiClN, and NH4Cl at 250–400 °C, TiCl4·5NH3, TiClN, TiNx, and NH4Cl at 450–650 °C, TiNx and NH4Cl at 700–1000 °C, and TiNx, NH4Cl, and HCl at 1100–1400 °C. The N/Ti atomic ratio, x, of the TiNx formed was 1.21 at 700 °C, 1.16 at 800 °C, 1.13 at 900 °C, and 1.10 above 1000 °C. The lattice constants of the TiNx formed are shown. The reaction process can be represented as follows: The reaction of gaseous TiCl4 with ammonia occurs first to form TiCl4·5NH3. Above ca. 220 °C, the TiCl4·5NH3 decomposes to TiClN. Above ca. 430 °C, the TiClN reacts with ammonia to form TiNx. Above ca. 1100 °C, in addition to these reactions, the reaction of TiCl2, formed by the reduction of TiCl4 with hydrogen resulting from the thermal dissociation of ammonia, with ammonia occurs to form TiNx. On heating the TiNx, formed by the vapor-phase reaction, at temperatures higher than 500 °C in an argon atmosphere, the value of x decreased and became close to that of the stoichiometric nitride, being 1.02 at 900–1100 °C.

The details of the reaction between vanadium trichloride oxide and hydrogen sulfide were examined at 20 and 60 °C. The main products by the reaction were vanadium dichloride oxide, sulfur, and hydrogen chloride. In addition to these products, small amounts of vanadium trichloride, vanadium tetrachloride, disulfur dichloride, and sulfur dioxide were formed. The formations of the above-mentioned reaction products can be explained as follows: The first stage is the reaction between vanadium trichloride oxide and hydrogen sulfide, 2VOCl3(1)+H2S(g)→2VOCl2(s)+S(s)+2HCl(g). Then the resulting sulfur reacts with the unreacted vanadium trichloride oxide, 2VOCl3(1)+2S(s)→2VOCl2(s)+S2Cl2(1). The resulting disulfur dichloride subsequently reacts with the unreacted vanadium trichloride oxide, 2VOCl3(1)+S2Cl2(1)→2VCl4(1)+S(s)+SO2(g). The resulting vanadium tetrachloride reacts with the sulfur formed during the reaction, 2VCl4(1)+2S(s)→2VCl3(s)+S2Cl2(1), and also reacts with hydrogen sulfide, 2VCl4(1)+H2S(g)→2VCl3(s)+S(s)+2HCl(g).

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Bi2(SO4)3 begins to decompose at 465°C, and the decomposition process of Bi2(SO4)3 can be represented as follows: Bi2(SO4)3\xrightarrow465°CBi2O3·2Bi2(SO4)3\xrightarrow550°C2Bi2O3·Bi2(SO4)3\xrightarrow580°C7Bi2O3·2Bi2(SO4)3\xrightarrow830°C12Bi2O3·Bi2(SO4)3\xrightarrow880°C28Bi2O3·Bi2(SO4)3\xrightarrow920°CBi2O3.

The products obtained by heating a mixture of Co3O4 and carbon in a SO2 stream were CoO and CoSO4 at 400–600 °C, Co1−xS and CoO at 650–700 °C, and Co1−xS (Co0.90S) at 750–800 °C. Sulfur was obtained outside the heating zone throughout the temperature range. The possible reactions during the above process were also examined. Further, thermodynamical consideration was made of the formation of Co1−xS. The formation process of Co1−xS (Co0.90S) from Co3O4 can be represented as follows: The reaction of carbon with SO2 occurs at first to form sulfur. Above ca. 400 °C, the reaction of Co3O4 with SO2 occurs to form CoO and CoSO4. Above ca. 500 °C, the reductions of Co3O4 with carbon and with sulfur also occur to form CoO. Above ca. 600 °C, the reduction of Co3O4 with carbon occurs to form CoO. Above ca. 650 °C, Co1−xS is formed by the reaction of CoO with sulfur, both of which had been formed by the above reactions.