Sorption Studies

Hydraulics and Dynamics of Backwash in Filtration with Activated Carbon to Reduce Iron and Manganese in Groundwater

Nur Iswanto, Ida Siswati Silalahi, Dewi Eviane, Agnes Dyah Novitasari Lestari — Wed, 18 Jun 2025 00:00:00 +0700

Well water used by the community often does not meet quality standards because it contains high levels of iron (Fe) and manganese (Mn). This study was intended to reduce Fe and Mn levels in well water by using filtration technique with activated charcoal media. The effect of hydraulics and backwash dynamics on the efficiency of filtration process was also investigated. The filtration apparatus was made of PVC pipe with the diameter of 4 inches and 120 cm height. The determination of optimum hydraulic conditions of filtration was carried out by varying the size of the activated carbon filter media (8-10, 12-14, and 16-18 mesh) and flow rate (1, 2, and 3 L/min) at the service time of 10 hours. The results showed that the size of filter media has significant effect on removal efficiency of Fe and Mn, with the most effective size was 16-18 mesh with the removal efficiency of 83.33% (Fe) and 93.33% (Mn). The highest head loss value in the filtration column was 0.15 cm, which occurred at the flow rate 3 L/min. Backwash should be performed after filtering process of 35 hours, 44 hours and 55 hours at the flow rate 1 L/min, 2 L/min, and 3 L/min repectively. The single filter design in this study reduced Fe and Mn concentration to meet clean water quality standards.

Kinetic Study of Mg(II) Adsorption on Activated Coal Bottom Ash

Mon, 30 Jun 2025 00:00:00 +0700

The research of sadsorption of Mg(II) ions on coal bottom ash as adsorbent has been carried out. The research was conducted by activating the coal bottom ash using concentrated HCl. Characterization of activated coal bottom ash was done by using Fourier Transform Infra-Red (FTIR) spectroscopy and X-Ray Difraction (XRD) analysis. Parameters of metal adsorption examined in this study include the effect of pH, mass of adsorbent, and interaction time. The concentration of each metal ion remaining in the solution after adsorption and desorption was determined using atomic absorption spectrophotometer. The result showed that activated coal bottom ash has been carried out. The optimum conditions for Mg(II) adsorption using 0.3 g coal bottom ash are at pH 5 with 60 minute contact. The Adsorption kinetics follow Ho model pseudo-second order with the rate constant 0.6182 and 0.998 correlation coefficient. These results highlight the potential of activated coal bottom ash as a low-cost, effective adsorbent for water treatment applications.

Adsorption Ni(II) on Magnetic Fulvic Acid-Chitosan: Kinetics and Isotherm Study

Mon, 30 Jun 2025 00:00:00 +0700

Indonesia, as one of the most populous countries in the world, requires clean water sources. Industrial waste that is improperly discharged pollutes water bodies with hazardous metals. Adsorption is one of the effective methods for reducing the concentration of harmful metals in water. This study utilized fulvic acid extracted from goat manure compost and combined it with chitosan and magnetite as an adsorbent material for Ni(II). The FTIR results for the magnetite-fulvic acid-chitosan composite showed a peak at 1627 cm⁻¹, indicating the presence of aromatic C=C, aromatic ring -OH, and quinone C=O groups, which confirm the binding of fulvic acid. BET analysis was performed on magnetite and magnetite-fulvic acid-chitosan, and the pore volume and pore size were found to be 0.177488 cm³/g and 6.5394 nm, respectively. The composite exhibited magnetic behavior due to the attraction between the magnetite-fulvic acid-chitosan and an external magnet. Adsorption tests using isotherm and kinetic models revealed that Ni(II) adsorption followed a multilayer mechanism and pseudo-second-order kinetics, with a b value of 121.68 mg/g and an experimental qe of 6.28 × 10⁻⁵ mol/g. This shows that the magnetite-fulvic acid-chitosan composite is a promising, sustainable, and magnetically separable adsorbent for the effective removal of nickel ions from contaminated water.