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Photooxidative degradation of pre-treated Palm oil mill effluent for removal of chemical oxygen demand, biological oxygen demand and color by UV/TiO 2 system has been investigated in a cylindrical glass photoreactor whose outer surface has been coated with titanium dioxide whereas the UV source has been placed inside the glass tube. The removal of these pollutants indicators has been found to follow pseudofirst-order kinetics and hence the electrical energy per order (E EO ) figure-of-merit is used to calculate approximately the electrical energy efficiency of the advanced oxidation process system. The higher dissolved oxygen (10 mg/L), lower initial concentration (6 mg/L) and acidic medium (pH = 3) have been found favorable to the photocatalytic degradation of palm oil mill effluent.

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Response Surface Methodology (RSM) is an optimization tool that can identify interrelationship between variables as being adopted by experiment/ research studies in food and herbal plants extraction niche area. This review discusses the optimization approach through utilization of research surface methodology either using central composite design or Box-Behnken method specifically in extraction processes. The use of analysis of variance (ANOVA) to evaluate the degree of accuracy held by the derived model is based on several responses. RSM helps to determine the best experimental design in order to identify the relationship between variables. This paper also discusses on the utilization of RSM to derive a model equation that later can be applied for response prediction and the determination of optimal conditions. The discussion presented here has clearly established the importance of choosing the right optimization tools such as response surface methodology (RSM). Major achievement of response surface methodology compared to conventional methods is the reduction of experimental runs for the same objective which is to obtain optimal variables condition/value for the highest output/response. Besides, the model derived can be used to predict the response prior to experimentation phase. Moreover, this step can help researcher or industries to focus on certain variables/aspect that contribute to the highest effect on process output. The use of either central composite design or Box-Behnken for extraction purposes especially with high-cost raw material is an economical alternative to traditional optimization approach through one-factor method. Combining extraction process with RSM can cause significant degree of accuracy in model prediction.

Abstract. Polysulfone (Psf) composite membrane consist of activated carbon, polyethyleneimine and silver nitrate was prepared by phase inversion. The activated carbon (AC) act as adsorbent to adsorb heavy metal present in synthetic waste water while polysulfone membrane act as support. Phase inversion was carried out on different composition of activated carbon from 0 to 0.9% while other component are remain constant. The surface morphology of composite membrane was characterized by scanning electron microscopy (SEM) while heavy metal absorption was quantified by atomic absorption spectrometer (AAS). The SEM image show symmetric membrane matrix with sponge structure. The composite membrane with 0.9wt% AC has the highest water flux as well as removal of heavy metal (chromium, lead, silver and cadmium) compare to composite membrane with 0.3wt% AC and 0.5wt% AC. The percentage of heavy metal reduction by composite membrane 0.9wt% AC was 35% cadmium, 19% chromium, 16% silver and 2% lead. The result indicated that the introduction of 0.9wt% AC indeed plays an important role towards enhancing the adsorption of heavy metal in water.

This paper discusses the extraction of an antioxidant compound, which is ascorbic acid or vitamin C, from a banana peel using an ultrasound-assisted extraction (UAE) method. The type of banana used was Musa acuminata also known as “PisangKepok” in Malaysia. The investigation includes the effect of solvent/solid ratio (4.5, 5 g and 10  ml/g), sonication time (15, 30 and 45 mins) and temperature variation (30 , 45  and 60oC ) on the extraction of ascorbic acid compounds from the banana peel to determine the best or optimum condition of the operation. Out of all extract samples analyzed by redox titration method using iodine solution, it was found that the highest yield was 0.04939 ± 0.00080 mg that resulted from an extraction at 30oC for 15 mins with 5 ml/g solvent-to-solute ratio.KEYWORDS:  Musa acuminata; ultrasound-assisted extraction; vitamin C; redox titration

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