Optimization and adsorption modeling of lead ions (II) on carbonaceous materials: Comparative evaluation of raw and citric acid-modified commercial activated carbon and tea waste derived biochar
DOI:
https://doi.org/10.31699/IJCPE.2026.1.11Keywords:
Lead Ions (II) Removal; Adsorption; Commercial Activated Carbon; Isotherms and kinetics; Tea Waste Derived Biochar; Citric Acid ModificationAbstract
The article investigated the effectiveness of removal (R%) of a batch study in the removal of lead (II) ions from synthetic aqueous water. A number of experiments were performed to determine the optimal parameters for the maximum removal procedure by using commercial activated carbon. The primary process variables studied included initial lead (II) ions concentration (pb (II)), pH, adsorbent particle size, dosage of adsorbent, and adsorption time.
The maximum removal occurred at an initial pb (II) ions concentration of 10 ppm, a pH of 5, an adsorbent dosage of 0.3 g with a particle size of 75 µm, and an adsorption time of 75 min. This research employed isotherm models to determine how the system reached a stable state. Langmuir model confirmed the largest accuracy, as evidenced by the results with a correlation coefficient (R²) of about 97.91%. The kinetic data was the most accurately described by pseudo-second-order model (PSO), suggesting that chemisorption is the limiting factor in the reaction rate, which was supported by a correlation coefficient of 99.5%. Four different adsorbent materials were investigated to evaluate their lead ions (II) removal %: commercial activated carbon (CAC), tea waste-derived biochar (TWDB), and CAC and TWDB modified with citric acid (CAC-CA and TWDB-CA). The study demonstrated that these four adsorbents were very effective and inexpensive agricultural waste may serve as an efficient method to remove pb (II) ions from contaminant water.
Received on 09/02/2026
Received in Revised Form on 12/03/2026
Accepted on 14/03/2026
Published on 30/03/2026
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