Dataset on hydration, microstructure, mechanical performance and environmental impacts of Portland cement incorporating waste-derived ferrous sulfate

Description

This dataset contains raw and processed experimental data supporting the study of Portland cement systems incorporating waste-derived ferrous sulfate hydrates (FeSO₄·xH₂O) as a partial replacement for natural gypsum. The data were generated to characterize hydration behavior, phase evolution, microstructural development, mechanical performance, chromium reduction behavior, and environmental impacts associated with alternative sulfate regulation in ordinary Portland cement. The dataset includes raw X-ray diffraction (XRD) patterns and Rietveld refinement outputs for identifying and quantifying hydration phases, thermogravimetric (TG/DTG) datasets for evaluating mass-loss events associated with AFt/AFm phases, portlandite, and carbonates, and scanning electron microscopy (SEM) images documenting microstructural features at early curing ages. Chemical composition data obtained by XRF and ICP-OES are provided for raw materials and unhydrated binders. Mechanical performance data include raw compressive strength results measured at 3, 7, 14, and 28 days, as well as Vicat initial and final setting-time measurements. Additional datasets include soluble Cr(VI) concentration measurements and life-cycle inventory data used for cradle-to-gate environmental assessment. All data are organized into clearly labeled folders corresponding to each experimental technique. The dataset is intended to support reproducibility, enable reanalysis using alternative modeling or analytical approaches, and facilitate comparative studies on sulfate-regulating additives, waste-derived cement components, and low-carbon cement systems.

Steps to reproduce

1. Prepare ordinary Portland cement (OPC) clinker and natural gypsum. Synthesize waste-derived ferrous sulfate hydrates (FeSO₄·xH₂O) from LD steelmaking sludge and waste sulfuric acid using a cyclic reaction–filtration process, including dissolution at 70 °C, filtration, and low-temperature crystallization at 5 °C. Dry the obtained FeSO₄·xH₂O at 40 °C and homogenize the crystalline products prior to use. 2. Prepare cement binders by partially replacing natural gypsum with FeSO₄·xH₂O at 0%, 25%, 50%, 75%, and 100% of the total sulfate source. Dry-blend clinker, gypsum, and FeSO₄·xH₂O, and grind the mixtures in a laboratory ball mill until a Blaine fineness of approximately 4530–4590 cm²/g is achieved. 3. For hydration and phase characterization, prepare cement pastes at a fixed water-to-cement ratio. Cure the samples under controlled temperature (20 ± 1 °C) and relative humidity (>95%) until the designated ages. 4. Perform X-ray diffraction (XRD) measurements using Cu Kα radiation over a 2θ range of 5–70°. Conduct Rietveld refinement for quantitative phase analysis. Carry out thermogravimetric and derivative thermogravimetric analysis (TG/DTG) from 40 to 1050 °C at a heating rate of 10 °C/min under nitrogen atmosphere. 5. Observe microstructural features using scanning electron microscopy (SEM) after solvent exchange with isopropanol, vacuum drying, and conductive coating of fractured paste samples. 6. Measure initial and final setting times using a Vicat apparatus in accordance with ASTM C191. Determine compressive strength of mortar specimens at 3, 7, 14, and 28 days following ASTM C109/C109M. 7. Quantify soluble hexavalent chromium (Cr(VI)) using alkaline extraction and ICP-OES analysis. Compile life-cycle inventory data for cradle-to-gate environmental assessment based on measured energy, water, and material inputs. 8. Access the raw datasets provided in the corresponding folders (XRD, TG_DTG, SEM, XRF_ICP, Strength, Setting_time, Cr_VI, and LCA). Reanalysis can be performed using standard crystallographic, thermal analysis, image analysis, and statistical software.

Institutions

• Korea Institute of Ceramic Engineering and Technology

  Gyeongsangnam-do, Jinju
• Yonsei University

  Seoul, Seodaemun-gu

Categories

Funders

• MOTIR, Korea

  Grant ID: RS-2024-00438915

Licence