Iminodiacetic acid modified kenaf fiber for waste water treatment

In the present study, iminodiacetic acid (IDA)-modified kenaf fiber, K-IDA formed by the chemical modification of plant kenaf biomass was tested for its efficacy as a sorbent material towards the purification of waste water. The K-IDA fiber was first characterized by the instrumental techniques like Fourier transform infrared (FTIR) analysis, elemental analysis (CHNSO), and scanning electron microscopy (SEM). On testing for the biosorption, we found that the K-IDA has an increment in the adsorption of Cu²⁺ ions as compared against the untreated fiber. The Cu²⁺ ions adsorption onto K-IDA fits very well with the Langmuir model and the adsorption maximum achieved to be 91.74 mg/g. Further, the adsorption kinetics observed to be pseudo second-order kinetics model and the Cu²⁺ ions adsorption is a spontaneous endothermic process. The desorption study indicates a highest percentage of Cu²⁺ of 97.59% from K-IDA under 1 M HCl solution against H₂SO₄ (72.59%) and HNO₃ (68.66%). The reusability study indicates that the efficiency did not change much until the 4th cycle and also providing enough evidence for the engagement of our biodegradable K-IDA fiber towards the removal of Cu²⁺ ions in real-time waste water samples obtained from the electroplating and wood treatment industries

On-line preconcentration of ultra-trace thallium(I) in water samples with titanium dioxide nanoparticles and determination by graphite furnace atomic absorption spectrometry

A new method has been developed for the determination of Tl(I) based on simultaneous sorption and preconcentration with a microcolumn packed with TiO2 nanoparticle with a high specific surface area prepared by Sonochemical synthesis prior to its determination by graphite furnace atomic absorption spectrometry (GFAAS). The optimum experimental parameters for preconcentration of thallium, such as elution condition, pH, and sample volume and flow rate have been investigated. Tl(I) can be quantitatively retained by TiO2 nanoparticles at pH 9.0, then eluted completely with 1.0 mol L−1 HCl. The adsorption capacity of TiO2 nanoparticles for Tl(I) was found to be 25 mg g−1. Also detection limit, precision (RSD, n = 8) and enrichment factor for Tl(I) were 87 ng L−1, 6.4% and 100, respectively. The method has been applied for the determination of trace amounts of Tl(I) in some environmental water samples with satisfactory results