Department of Biological and Environmental Sciences

Permanent URI for this collectionhttp://erepository.kibu.ac.ke/handle/123456789/229

Browse

Browsing Department of Biological and Environmental Sciences by Subject "Adsorption"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Equilibrium, Kinetic, and Thermodynamic Studies of Pb (II) ions Adsorption onto Modified Tamarind Fruit Pulp
    (American Journal of Chemistry, 2026-10) Mukhalisi, Stellah Nelima; Maingi, Francis M.; Kowanga, Keno
    The challenge of accessing clean drinking water in urban Kenya is compounded by contamination from heavy metals, leading to serious health risks such as kidney and brain damage. Industrialization and technological advancement have exacerbated the problem of increase of Pb (II) ions and other heavy metals in water ecosystem through industrial effluents. This study investigated the use of modified tamarind fruit pulp (MTFP) for the adsorption of (Pb II) ions from synthetic wastewater. Characterization techniques like XRF and FT-IR were utilized, and adsorption experiments were conducted by varying pH, contact time, temperature, dosage, and initial concentrations of the metals. The results were analysed statistically using ANOVA, with significant differences at P ≤ 0.05. The equilibrium studies indicated that the adsorption of Pb (II) ions was best represented by the Freundlich model, with adsorption capacities of 1.30 and 1.67 mg/g for unmodified tamarind fruit pulp (UTFP) and modified tamarind fruit pulp (MTFP), respectively. Thermodynamic study showed that the adsorption process was thermodynamically spontaneous and endothermic. Kinetic studies revealed that chemisorption was the rate limiting step in the adsorption of Pb (II) ions. This information revealed the enhanced capabilities of MTFP to effectively remove Pb (II) ions from wastewater, showcasing its potential as an eco-friendly adsorbent.
  • No Thumbnail Available
    Item
    Oxalic Acid Functionalized Diatomite for Enhanced Lead (II) ions Adsorption from Wastewater
    (Physical Chemistry, 2026-06-08) Masai, Winny Chebeni; Maingi, Francis M.; Makhanu, Maximilla
    Increased global demand for batteries and paints has resulted in higher levels of heavy-metal contamination in waterways, harming aquatic life and human health. Lead is of particular concern due to its non-biodegradable nature and persistence at trace levels. Various technologies have been developed for heavy metal removal from wastewater, with adsorption being the most effective and resource-efficient. Information in literature shows that diatomite has the ability to adsorb heavy metal ions from aqueous media but suffers from a low adsorption capacity and specific surface area. This study therefore focused on enhancing the adsorption capacity of low-cost diatomite by functionalizing it with carboxyl groups via oxalic acid. Characterization techniques, including XRF, FT-IR, XRD, and Raman spectroscopy, confirmed the successful functionalization. Batch adsorption experiments demonstrated that functionalized diatomite effectively removed over 80% of Pb (II) ions, with an adsorption capacity of 8.00 mg/g. These findings suggest that functionalized diatomite is a promising potential adsorbent for remediation of heavy metal ions from wastewater.