In this study, we selected materials that efficiently adsorb total hydrocarbons (THCs) from petrochemical storage facilities and applied four types of activated carbons to adsorb THCs to evaluate their properties. Four gases with low boiling points, namely, ethylene, ethane, propylene, and propane, generated via petrochemical storage facilities, were selected and mixed to a constant concentration with four types of materials and used to investigate the adsorption capacities and desorption properties. The adsorbents comprised two raw materials and two chemically activated materials. The specific surface areas of activated palm (2085 m²/g) and coal (1752 m²/g), which are chemically activated carbons, exhibited a twofold increase compared to those of raw palm (1232 m²/g) and coal (946 m²/g). Thus, we identified the correlations between the physical properties of the activated carbon adsorption materials and their adsorption capacities for four low-boiling-point THCs generated by petrochemical storage facilities.

Due to its acidic nature and high fluoride concentration, hydrated lime (Ca(OH)₂) is commonly used for neutralization and fluoride control in semiconductor wastewater treatment. This study investigated the efficacy of treating high fluoride-containing wastewater using hydrated lime derived from oyster shells as an alternative to limestone. Overall, the characteristics of removing pollutants in acidic wastewater using shell-based hydrated lime showed similar patterns to hydrated lime from limestone. The treatment efficiency was 50% or less under theoretical Ca/F molar ratio (=0.5) conditions for the formation of fluorite (CaF₂), while the fluorine removal rate reached 99% under somewhat higher Ca/F conditions due to the influence of ionic components in the wastewater. Interestingly, chloride content did not increase even in the initial reaction stages, in contrast to our concerns about oyster shells generally containing salt to a certain extent due to their growth in seawater; instead, the chloride concentration decreased over time, similar to nitrate (NO₃⁻). In controlling fluoride in wastewater, surpassing the theoretical Ca/F molar ratio, particularly considering the presence of other anionic species such as SO₄^²− and PO₄³⁻, the optimal Ca/F ratio for fluoride removal was found to be 1.59. This value is approximately 16% lower than the calculated value (Ca/F = 1.85) when accounting for other anions. X-ray diffraction results confirmed the presence of CaSO₄, Ca₃(PO₄)₂, and CaF₂ in the precipitate recovered after the reaction, indicating the effective removal of ionic contaminants. This observation suggests that oyster shell-derived hydrated lime could serve as a viable calcium resource for treating acidic wastewater and represents a potential alternative to traditional limestone-based methods.

An integrated calculation combining X-ray fluorescence (XRF), thermogravimetric analysis (TGA), and elemental analysis (EA) was applied to the compositional assessment of commercial green silicon carbide (SiC) and biomass-derived synthesized SiC. Total carbon measured by EA and the mass loss assigned to free carbon by TGA were combined through the stoichiometric carbon fraction of SiC. The XRF inorganic elemental profile and the TGA mass gain, expressed as a free-Si equivalent, were used for a complementary component-balance calculation. Carbon-based SiC estimates were 99.1 and 99.4 wt.% for the commercial and synthesized materials, respectively, compared with KS L 1612 values of 99.7 and 98.6 wt.%. With hydrogen and nitrogen included and zero initial silica assumed, the component totals were 100.6 and 101.2 wt.%. The integrated approach couples carbon-based estimation with a balance check that exposes inconsistencies between thermal assignments and compositional inputs. This two-material application demonstrates the calculation and component-balance check under the stated assumptions; method precision and trueness require independent experimental validation.