Suhaimi Abdul Talib

Biosorption of Iron (III) from Aqueous Solution Using Pleurotus ostreatus Spent Mushroom Compost as Biosorbent

The ability of Pleurotus ostreatus spent mushroom compost for the biosorption of Iron (III) from aqueous solutions was investigated. The study was conducted in batch experiments under varying operating conditions. The optimum Iron (III) biosorption was achieved at an initial pH ranging from 4 to 5, contact time of 10 minutes and initial Iron (III) concentration of 50 mg/L using half-saturation constant of 0.4 g biosorbent dosages. The results indicated that the Iron (III) biosorption onto Pleurotus ostreatus spent mushroom compost were well fitted with the Langmuir isotherm model and a second-pseudo order kinetic model.

Investigation of ethyl lactate as a green solvent for desorption of total petroleum hydrocarbons (TPH) from contaminated soil

Treatment of oil-contaminated soil is a major environmental concern worldwide. The aim of this study is to examine the applicability of a green solvent, ethyl lactate (EL), in desorption of diesel aliphatic fraction within total petroleum hydrocarbons (TPH) in contaminated soil and to determine the associated desorption kinetics. Batch desorption experiments were carried out on artificially contaminated soil at different EL solvent percentages (%). In analysing the diesel range of TPH, TPH was divided into three fractions and the effect of solvent extraction on each fraction was examined. The experimental results demonstrated that EL has a high and fast desorbing power. Pseudo-second order rate equation described the experimental desorption kinetics data well with correlation coefficient values, R2, between 0.9219 and 0.9999. The effects of EL percentage, initial contamination level of soil and liquid to solid ratio (L/S (v/w)) on initial desorption rate have also been evaluated. The effective desorption performance of ethyl lactate shows its potential as a removal agent for remediation of TPH-contaminated soil worldwide.

Improving Mathematical Model in Biodegradation of PAHs Contaminated Soil Using Gram-Positive Bacteria

ABSTRACT In published literature there are limited studies on the estimation of kinetic parameters of polycyclic aromatic hydrocarbons (PAHs) in soil. In addition, neither the kinetic studies were performed with Gram-positive bacteria nor conducted under non-indigenous condition in order to understand their removal performance. Thus, a mathematical model describing biodegradation of phenanthrene-contaminated soil by Corynebacterium urealyticum, bacterium isolated from municipal sludge, was developed in this study. The model includes three kinetic parameters that were determined using TableCurve 2D software, namely qmax (maximum substrate utilization rate per unit mass of bacteria), X (biomass concentration) and Ks (substrate concentration at one half the maximum substrate utilization rate). These parameters were evaluated and verified in five different initial phenanthrene concentrations. Highest degradation rate was determined to be 79.24 mg kg−1 day−1 at 500 mg kg−1 initial phenanthrene concentrations. This high concentration shows that bacteria perform better in contaminated sand compared to liquid media. High r2 values, ranging from 0.92 to 0.99, were obtained excluding 1000 mg/kg phenanthrene. The kinetic parameters, i.e., qmax and Ks, increased with the phenanthrene concentration and thus suggest that bacteria degrade at a higher degradation rate. This model successfully described the biodegradation profiles observed at different initial phenanthrene concentrations. The established model can be used to simulate the duration of phenanthrene degradation using only the value of the initial PAHs concentration.

Mn(II) Ions Biosorption from Aqueous Solution using Pleurotus Spent Mushroom Compost under Batch Experiment

The Pleurotus spent mushroom compost was selected as biosorbent to sorption Mn(II) ions. The Mn(II) ions biosorption was investigated under batch experiments. The influences of pH, contact time and initial Mn(II) concentration were also investigated. The optimum Mn(II) ions biosorption was achieved at pH 6, 20 minutes of contact time and 10 mg/L of initial Mn(II) concentration using 1.0 g biosorbent dosage. The Mn(II) ions biosorption experimental data were best described by the Langmuir isotherm model and pseudo-second order kinetic model. As conclusion, the Pleurotus spent mushroom compost can be used to sorption the Mn(II) ions from the aqueous solution.

Study of Fe(II) Biosorption Using Pleurotus Spent Mushroom Compost in a Fixed-Bed Column

The potential use of Pleurotus spent mushroom compost as a biosorbent for Fe (II) removal from aqueous solutions was investigated. The experiments were conducted in a fixed-bed column to investigate the influence of various parameters such as flow rate, bed depth and initial concentration on the biosorption of Fe (II). The results of breakthrough time, exhaustion time as well as the Fe (II) uptake and percentage of removal are highly influenced by the flow rate, bed depth and the initial Fe (II) concentration. The results demonstrated that the breakthrough time and exhaustion time increased with decreases in flow rate and initial Fe (II) concentration. Conversely, the breakthrough and exhaustion time decreased as the bed depth decreases.

Study of Heavy Metals Concentration from Different Steel-Based Industries Effluents

A study was conducted to identify and analyze heavy metals concentration in the steel industries effluents. The industrial effluents were collected from three different steel based factories in Shah Alam, Selangor, Malaysia. For each factory, the effluent samples were collected at two different points for determination of heavy metals concentration. Heavy metal concentrations were analyzed using Inductively Coupled Plasma Atomic Emission Spectroscopy. The results showed heavy metals (Cr, Fe, Mn, Ni and Zn) in the untreated effluent at Factory C have the highest concentrations compared with other steel-based factories. Also, the concentration of Fe, Mn and Ni in the treated effluent from Factory C were found above the permissible limits.

Biodegradation of PAHs in Soil: Influence of Initial PAHs Concentration

Most studies on biodegradation of Polycyclic Aromatic Hydrocarbons (PAHs) evaluate the effect of initial PAHs concentration in liquid medium. There are limited studies on evaluation in solid medium such as contaminated soil. This study investigated the potential of the bacteria, Corynebacterium urealyticum isolated from municipal sludge in degrading phenanthrene contaminated soil in different phenanthrene concentration. Batch experiments were conducted over 20 days in reactors containing artificially contaminated phenanthrene soil at different concentration inoculated with a bacterial culture. This study established the optimum condition for phenanthrene degradation by the bacteria under nonindigenous condition at 500 mg/kg of initial phenanthrene concentration. High initial concentration required longer duration for biodegradation process compared to low initial concentration. The bacteria can survive for three days for all initial phenanthrene concentrations.

Fe(II) Biosorption Using Pleurotus Spent Mushroom Compost as Biosorbent under Batch Experiment

A laboratory study was conducted to optimize the various parameters involved in Fe (II) biosorption under batch experiment and also to evaluate the biosorption performance using Pleurotus spent mushroom compost as biosorbent. The optimum Fe (II) biosorption was achieved at an initial pH 5, contact time of 30 minutes and initial Fe (II) concentration of 10 mg/L using 0.75 g biosorbent dosages. The study concluded that the Pleurotus spent mushroom compost was capable for removing of Fe (II) from aqueous solution.