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Remazol Brilliant Blue dye (RBB) is a harmful dye from the textile industry that can damage the environment and aquatic life. Since RBB is impossible to degrade in water by primary and secondary wastewater treatment, its removal is a challenge. An excellent treatment procedure is urgently anticipated to avoid the pollution spreading into the environment. Moreover, rice husk waste (RH) in Malaysia is abundant and generally dumped into landfills. Turning the waste into a value‐added product such as biochar as an effective adsorbent material for treating water pollutants is one of the initiatives in realizing the circular economy agenda. This study develops an organic porous material of biochar from RH and assesses the kinetic of RBB adsorption onto the rice husk biochar (RHB) in aqueous solution. The production of RHB was optimized by pyrolysis procedure at various temperatures, times, and particle sizes. The removal of RBB dye by RHB was investigated at different exposure times from 0 to 120 min under 100 rpm shaken and immersed conditions. The reduction of RBB concentrations using different RHB pyrolysis conditions has also been investigated. The dye removal efficiency by RHB increased with time and the highest removal efficiency (69.3%) was achieved by the smallest particle size of RHB which was produced at the highest pyrolysis temperature of 400°C (RHB‐400). The total pore volume and BET surface area of RHB‐400 were found to be 50.4827 m2/g and 0.00875 cm3/g, respectively. The adsorption kinetic study signifies that maximum adsorption has been completed within 90–120 min depending on the RHB conditions whereas two kinetic models such as pseudo‐first order and pseudo‐second order kinetic models were utilized to fit the experimental data and the results are more consistent with pseudo‐second order kinetic models. This study revealed that RHB can be used as adsorbent materials for dye removals, yet it is economical, environmentally friendly, and sustainable. [ABSTRACT FROM AUTHOR]

• Bacteria isolated from waterfall was identified as Serratia nematodiphila. • The bacteria produced a red-pigment characterized as prodigiosin. • Addition of oil substrate increased the prodigiosin production in fermentation. • Palm oil gave the comparable improvement in prodigiosin production. • The prodigiosin showed photovoltaic properties, and could be used as photosensitizer. Bacterial pigments are potential substitute of chemical photosensitizer for dye-sensitized solar cell (DSSC) due to its non-toxic property and cost-effective production from microbial fermentation. Serratia nematodiphila YO1 was isolated from waterfall in Malaysia and identified using 16S ribosomal RNA. Characterization of the red pigment produced by the bacteria has confirmed the pigment as prodigiosin. Prodigiosin was produced from the fermentation of the bacteria in the presence of different oil substrates. Palm oil exhibited the best performance of cell growth and equivalent prodigiosin yield compared to olive oil and peanut oil. Prodigiosin produced with palm oil supplementation was 93 mg/l compared to 7.8 mg/l produced without supplementation, which recorded 11.9 times improvement. Specific growth rate of the cells improved 1.4 times when palm oil was supplemented in the medium. The prodigiosin pigment produced showed comparable performance as a DSSC sensitizer by displaying an open circuit voltage of 336.1 mV and a maximum short circuit current of 0.098 mV/cm2. This study stands a novelty in proving that the production of prodigiosin is favorable in the presence of palm oil substrate with high saturated fat content, which has not been studied before. This is also among the first bacterial prodigiosin tested as photosensitizer for DSSC application. [ABSTRACT FROM AUTHOR]

Sabah (Malaysia) on the Island of Borneo has a high plant diversity (>8000 species) occurring on a wide range of soils, including ultramafic soils which are known to host hyperaccumulator plants. In this study a new approach ("Herbarium X-ray Fluorescence Ionomics") was used to obtain elemental data from herbarium specimens using non-destructive X-ray Fluorescence spectroscopy analysis. In total ~7300 specimens were thus analysed for nickel, cobalt, and manganese concentrations at the Herbarium of the Forest Research Centre (FRC) in Sepilok, Sabah. The measurements led to recording a total of 759 specimens (originating from 17 families in 30 genera and 74 species) as trace element hyperaccumulators, including 28 nickel hyperaccumulator species (in 10 families, 17 genera), 12 cobalt hyperaccumulator species (in 3 families, 7 genera), and 51 manganese hyperaccumulator species (in 12 families, 24 genera). The outcomes of this research demonstrate that X-ray Fluorescence scanning is highly useful approach for hyperaccumulator plant discovery in herbarium collections that has the potential to add vast numbers of hyperaccumulating taxa to the global inventory. • Handheld X-Ray Fluorescence analysis can be used to obtain elemental data from vast numbers of herbarium specimens. • In total, ~7300 herbarium specimens were analysed for nickel, cobalt, and manganese concentrations at the Herbarium of the Forest Research Centre (FRC) in Sepilok, Sabah, Malaysia. • This led to the discovery of 28 nickel hyperaccumulator species (in 10 families, 17 genera), 12 cobalt hyperaccumulator species (in 3 families, 7 genera), and 51 manganese hyperaccumulator species (in 12 families, 24 genera). [ABSTRACT FROM AUTHOR]

Textile industry, one of the largest exporting industries in Malaysia, generates azo dyes wastewater which cannot be easily decomposed biologically due to its high stability and xenobiotic nature. Conventional electrocoagulation (EC) system requires high energy consumption, resulting in higher operating cost while membrane system suffers from fouling. To eliminate these drawbacks, an integrated electrocoagulation – membrane (ECM) system has been proposed as one of the emerging methods for treating dye wastewater. However, feasibility analysis of the proposed system is yet to be conducted. This study proposes a statistical technique to evaluate the techno-economic feasibility of the system via John's Macintosh Project (JMP) software. From JMP, an equation represents the whole model had been obtained for each of the system, EC standalone and ECM system. The models have been validated experimentally it is proven all the models can reach dye removal efficiency of 96%. Overall, the total cost for ECM system (1 V and 1.0 g of NaCl) was 40.44% cheaper than the conventional dye treatment method with total cost of 1.079 million MYR. EC standalone system at 1 V and 1.0 g however were found to be more economically feasible with 0.325 million MYR or 82.07% cheaper compared to conventional photocatalytic method. EC standalone system was also more economical than ECM system due to lower capital cost expended for installation of membrane tank and additional membrane purchase. [Display omitted] • Economic comparisons of EC and ECM were evaluated at large scale in dye removal. • Process modelling of EC and ECM at lower voltage (1 V and 2 V) were compared. • 96% removal of Celestine Blue dye were set for EC and ECM at 1 V and 1.0 g NaCl. • EC is more economical with 82.07% (0.325 MMYR) cheaper than photocatalytic method. [ABSTRACT FROM AUTHOR]