Insight observation into rapid discoloration of batik textile effluent by in situ formations of zero valent iron

This study aimed to investigate the discoloration of textile effluent from batik industrial wastewater by Fenton oxidation process using Fe(II), Fe(III) and in situ formation of zero valent iron (Fe(0)). The controlled parameters indicate the Fenton oxidation reaction is ideal on effluent at pH5, concentration colour of 4005 mg/L Pt-Co units using 0.5 mg/mL of catalyst dosage to meet the regulation for Malaysian quality water standard. The optimization of Fe(0) precursors, Fe(II) shows a higher discoloration efficiency in comparison with Fe(III). The synthesized particles of Fe(0) shows a nano spherical structure in the diameter range of 20-70 nm, aggregated and into a chain-like formation. Subsequently, the performance of Fe(0) was improved up to 97% discoloration in comparison with 89% discoloration by Fe(II). Whereas, the in situ formation of Fe(0) in batik effluent shows a complete discoloration ascribable to higher reactivity than partially oxidized of synthesized ex situ Fe(0). On top of that, in situ Fe(0) performed at the expeditious reaction in less than five min. Additionally, the regeneration of Fe(0), Fe(II) and Fe(III) show a potential of catalyst recyclability up to three cycles of Fenton oxidation but with a tolerable reduction to 62.1% of effluent discoloration

Preparation and characterization of calcium hydroxyphosphate (hydroxyapatite) from tilapia fish bones and scales via calcination method

Calcium hydroxyphosphate (hydroxyapatite) is a calcium phosphate that is widely used in biomedical application. Hydroxyapatite is an excellent component for bone substitutes for their chemical and structural similarity to natural bone component. In this research, hydroxyapatite was synthesized from tilapia fish bones and scales using calcination method with 3 different temperatures namely 1000 °C, 900 °C and 800 °C. The obtained hydroxyapatite powder was characterized using several techniques such as Fourier-Transform infrared spectroscopy Attenuated total reflection (FTIR-ATR), scanning electron microscope (SEM), proximate analysis and X-ray diffraction (XRD). The results indicated that temperature 1000 °C has the highest weight loss with 21.825 g compared to the temperature 800 °C and 900 °C. From FTIR-ATR analysis, the presence of characteristic peaks for hydroxyl group, phosphate groups and water molecule indicated that the powder were hydroxyapatite. SEM results showed that increasing temperature had led to more dense structure. The hydroxyapatite powder were further analysed for their proximate analysis. The results proved that the highest contents of ash, fat, moisture and crude protein were observed at 1000 °C as compared to 900 °C and 800 °C. Based on this study, it revealed that produced pure hydroxyapatite from natural resources could be a potential candidate for food industry as protein enhancer

Highly efficient preparation of ZnO nanorods decorated reduced graphene oxide nanocomposites

A one-step method for the synthesis of zinc oxide/reduced graphene oxide (ZnO/rGO) nanocomposites by a hydrothermal technique is reported. This simple method involves a hydrothermal treatment of a solution comprising graphene oxide (GO), Zn(CH3COO)2.2H2O, NaOH and NH3.H2O. The concentration of GO as a starting material plays an important role in the density distribution of ZnO nanorods on the rGO sheets and on the percentage of the formation of ZnO/rGO nanocomposites. The resulting rod-like ZnO nanoparticles formed on the rGO sheets, in high density, has a potential in the gas sensing application

The Development of Efficient Photocatalysts to Improve Light Absorption and Charge Separation Properties for Photoelectrochemical Water Splitting

Photoelectrochemical (PEC) water splitting is a process that uses solar energy to split water into hydrogen and oxygen using a specialised photoelectrochemical cell. PEC water splitting has the potential to be an attractive way of producing hydrogen gas, as it can be powered by renewable energy sources such as sunlight. Generally, research advancement in PEC water splitting has shown positive potential in developing a sustainable and efficient way of producing hydrogen gas using renewable energy sources. However, the efficiency and viability of PEC water splitting significantly depend on a few key factors, including photocatalyst efficiency, device architecture optimisation, and electrode stability. Thus, this chapter focuses on the most up-to-date developing materials with improved light absorption and charge separation properties for PEC water splitting. In addition, this chapter also discussed future trends and success challenges of the PEC water splitting to provide an outlook for future research