The high content of natural organic matter (NOM) is one of the challenging characteristics of peat water. It is also highly contaminated and contributes to some water-borne diseases. Before being used for potable purposes, peat water must undergo a series of treatments, particularly for NOM removal. This study investigated the effect of coagulation using aluminum sulfate coagulant and adsorption using powdered activated carbon (PAC) as a pretreatment of ultrafiltration (UF) for removal of NOM from actual peat water. After preparation and characterization of polysulfone (Psf)-based membrane, the system’s performance was evaluated using actual peat water, particularly on NOM removal and the UF performances. The coagulation and adsorption tests were done under variable dosings. Results show that pretreatment through coagulation–adsorption successfully removed most of the NOM. As such, the UF fouling propensity of the pretreated peat water was substantially lowered. The optimum aluminum sulfate dosing of 175 mg/L as the first pretreatment stage removed up to 75–78% NOM. Further treatment using the PAC-based adsorption process further increased 92–96% NOM removals at an optimum PAC dosing of 120 mg/L. The final UF-PSf treatment reached NOM removals of 95% with high filtration fluxes of up to 92.4 L/(m2.h). The combination of three treatment stages showed enhanced UF performance thanks to partial pre-removal of NOM that otherwise might cause severe membrane fouling.

No abstract

Decolorization of synthetic dyes by laccase produced from newly isolated Trametes hirsuta EDN084 under in-vitro condition was investigated in this study. Partial purification was conducted using ultrafiltration Amicon 10K at 5000 x g for 20 min. Laccase (0.1 U/mL) could decolorize 50% remazol brilliant blue R (RBBR), 47% reactive blue 4 (RBlue4), 51% acid blue 129 (AB129), 21% acid blue 25 (AB25), 40% acid blue 113 (AB113), 11% acid orange 7 (AO7), 2% reactive black 5 (RBlack5), 2% reactive red 120 (RR120), and 85% direct blue 71 (DBlue71) for 4 h. In order to improve the decolorization, the addition of violuric acid (VA), 2, 2, 6, 6-tetramethylpiperidine 1-oxyl (TEMPO), and 1-hydroxybenzotriazole (HBT) were individually assayed. The result showed that decolorization was improved significantly (2 to 30-fold) after the addition of 1 mM VA. This study suggests that mediator VA is suitable for the enhanced decolorization of synthetic dyes by laccase from T. hirsuta EDN084.

No abstract