The Raw Sulfate Turpentine Purification from Sulfur-Containing Compounds

Desulfurized and Hydrogenated Crude Sulfate Turpentine (HCST): A Biofuel Derived from a Waste of the Pulp and Paper Industries

“…The main components are α-pinene, β-pinene, and Dlimonene, with much minor amounts of other terpenoids, such as camphene, β-myrcene, and β-fenchol, and this composition is almost identical to a turpentine sample from pine resin distillation. 8 It is noticeable the almost total absence of sulfur compounds found in the GC-MS spectrum, which are undoubtedly present because of the high sulfur content and stagnant odor of the CST, except two minor compounds with poor identification qualities: a thiomethyl compound that appears at the end of chromatogram, 47 min, and traces of mintsulfide, a compound usually found in CST (see structures in Figure 4). A probable reason is that the sulfur compounds present in CST are mostly light mercaptans, sulfides, and disulfides, and they are expelled from the injection port of the GC-MS jointly with the dichloromethane solvent.…”

“…As a result of the sodium sulfide present in the white liquor, the CST leaves the digester with a sulfur content higher than pine resin turpentine . While the latter has a sulfur content between 40 and 50 mg/kg, the CST obtained from the Kraft process varies between 200 and 20000 mg/kg, depending on the type of wood used and the type of Kraft factory . The Kraft process involves the generation of a large amount of CST, which could be used as biofuel once the sulfur is removed and its combustion properties are improved.…”

Refining of crude sulfate turpentine obtained from a kraft pulp mill: A pilot scale treatment

“…Hydrodesulphurization based on cobalt molybdenum catalyst reduced initial sulphur content from 501 ppm to 55 ppm (Lloyd and Bruce 1994). H2O2 oxidation and rectification process reduced the sulphur content from 20,000 ppm to 3000 ppm and 70 ppm respectively (Tyurmina et al 2017). Various refining steps of CST as batch distillation, N2 stripping, sodium hypochlorite treatment, and water wash, respectively, reduced the sulphur content of final products to 1147 ppm, 552 ppm, 26 ppm, and less than 10 ppm (Hamby et al 1972).…”

“…The odor problems arising from manufacturing operations of kraft processing, the odor thresholds of the sulfurous odorant chemicals (Leonardos et al 1969), and final sulphur content (Collins and Brunswick 1946;Prochazka and Foy 1958;Lloyd and Bruce 1994;Hwang et al 1994;Wang et al 2011;Tyurmina et al 2017;Sinhmar and Gogate 2020) are of vital importance (Rehman et al 2016). They need to be controlled to represent the effect of chemical purity represented in Table 1.…”