Performances of sandwich membrane in reclamation of water from final discharged POME

An investigation was made to examine the performance of sandwich configurations of paired ultrafiltration membranes in reclamation of water from final discharged POME. Two membranes were sandwiched together in different configurations without spacer. Two types of membrane were used in this study which were PES and RC with MWCO 5kDa. The sandwich configurations were known as SS-Sandwich, SB-sandwich, where S indicates that the skin layer faces the feed and B indicates that support layer faces towards the feed. The result of single membrane was compared with both sandwich arrangement. SS-sandwich configuration showed the best permeate quality for PES MWCO 5kDa. The pollutant reduced range up to 80%-90% compared to single membrane which were 60%-70% range. The quality of permeate obtained for total dissolved solid (TDS), suspended solid (mg/L), turbidity, BOD5, COD, were 535 mg/L, <25 mg/L, 0.88 NTU, BOD5 23.3 mg/L, and 48 mg/L. The quality of permeate from SS-sandwich membrane of 5 kDa was beyond reuse standard and approaching drinking water standard for TSS, TDS and turbidity. Therefore it can be concluded that, water reclaimed from treating final discharged from palm oil mill effluent using ultrafiltration technique with right sandwich configuration at optimum operating conditions was successfully complied with WHO reuse water standard

Transformation of cyclodextrin glucanotransferase (CGTase) from aqueous suspension to fine solid particles via electrospraying

In this study, the potential of electrohydrodynamic atomization or electrospraying to produce nanometer-order CGTase particles from aqueous suspension was demonstrated. CGTase enzyme was prepared in acetate buffer solution (1% v/v), followed by electrospraying in stable Taylor cone-jet mode. The deposits were collected on aluminium foil (collector) at variable distances from the tip of spraying needle, ranging from 10 to 25 cm. The Coulomb fission that occurs during electrospraying process successfully transformed the enzyme to the solid state without any functional group deterioration. The functional group verification was conducted by FTIR analysis. Comparison between the deposit and the as-received enzyme in dry state indicates almost identical spectra. By increasing the distance of the collector from the needle tip, the average particle size of the solidified enzyme was reduced from 200 ± 117 nm to 75 ± 34 nm. The average particle sizes produced from the droplet fission were in agreement with the scaling law models. Enzyme activity analysis showed that the enzyme retained its initial activity after the electrospraying process. The enzyme particles collected at the longest distance (25 cm) demonstrated the highest enzyme activity, which indicates that the activity was controlled by the enzyme particle size

Bleached kenaf microfiber as a support matrix for cyclodextrin glucanotransferase immobilization via covalent binding by different coupling agents

Enzyme immobilization via covalent binding provides a strong interaction between enzyme and support material. In this study, the effect of different coupling agents (spacer arms and ligands) in cyclodextrin glucanotransferase (CGTase) immobilization on bleached kenaf microfiber as a support matrix was investigated. The immobilized CGTase properties such as storage stability, thermal stability and reusability were evaluated. Immobilized CGTases on microfiber resulted in 0.162–0.24 U/mg-fiber when 55.6 U/mL of CGTase activity was initially added during the immobilization. The highest storage stability (60 °C) was shown by CGTase that was immobilized with ethylenediamine and o-phthalaldehyde, whereby 60% of its activity remained after 15 days. Its high stability was also confirmed by the lowest deactivation constant, kd that was obtained at 25 °C (0.0161 day−1) and 60 °C (0.0361 day−1). The CGTase immobilized using ethylenediamine and glutaraldehyde has shown the best retention of enzyme activity up to 72.72% after 12 cycles of batch reaction. The results indicate that kenaf microfiber has potential to be applied as a support for enzyme immobilization and its enzymatic properties were affected by the coupling agents

Electrophoretic mobility of Tween 80-encapsulated agarwood oil in aqueous

A study on the feasibility of using gel electrophoresis technique in grading the agarwood oil quality was investigated. Prior to electrophoresis, the emulsified agarwood oil droplets were screened by a diffuse layer of ions that have equal absolute charge to that of the droplets surface charge in aqueous phase. The condition was obtained by varying the concentrations of non-ionic surfactant; Tween 80 until the critical aggregation concentration (CAC) value of 0.0167% (v/v) was achieved. The prepared droplets suspended in the aqueous within nano-metre size and had ability to migrate through the agarose gel with its own specific electrophoretic mobility. However, due to the limitation of gel pore size, only large oil droplets (>200 nm) indicated visible bands. Overall, a novel work for grading the emulsified agarwood oil droplet with its own electrical properties was feasible

Immobilization of colloidal particles into sub-100nm porous structures by electrophoretic methods in aqueous media

Conventional direct current (DC) and pulse-DC assisted electrophoretic depositions of colloidal particles, with average sizes of 10 and 50 nm, into sub-100 nm scaled pore arrays made from anodized aluminum substrate has been investigated. At the applied voltages lower than the decomposition voltage of water (∼1 V), the number concentration of particle deposited on the surface by conventional DC was higher than that of pulse DC. The number of deposited particles increased with increasing pH. Deposition efficiency inside the pores can be enhanced by applying pulse DC. In the case of high (∼10 V) applied voltage, no particles were observed inside pores even though pulse DC has been applied. The adhesion strength (removal behavior) of deposition was evaluated by applying a particle detachment simple system based on ultrasonic energy. The particles deposited inside the pores were not detached compared with those of the surface of the substrate

Mass transfer with reaction kinetics of the biocatalytic membrane reactor using a fouled covalently immobilised enzyme layer (α–CGTase–CNF layer)

A dynamic mathematical model was used in this study to describe the mass transfer and reaction kinetics of a fouled α–CGTase–CNF layer in a biocatalytic membrane reactor (BMR) system. BMR performance was evaluated based on the effect of substrate concentration and pneumatic gauge pressure on the permeate flux, total permeate volume, starch conversion, and α-CD production. A model is introduced based on the layer of mass limit as the resistance blocking mechanism with reaction kinetics on the fouled α–CGTase–CNF layer. Important unknown parameters of the constants describing the layer resistance, KML0 and the kinetic constant of Michaelis-Menten, kcat, for mass transfer and its reaction kinetics, were successfully estimated at 3.9 × 107 min/mL and 216.18 mg-starch/cm3⋅U⋅min, respectively, using the proposed models. The study found that the kcat value corresponding to the maximum efficiency of the enzyme on starch cyclisation was a critical parameter in the prediction of the BMR dynamic profiles. Thus, the proposed model in this study can be used for further development of the BMR system, with excellent hydrodynamic and reaction performance

Ultrafiltration of palm oil mill effluent: effects of operational pressure and stirring speed on performance and membranes fouling

Palm oil mill effluent (POME) is the largest pollutant discharged into the rivers of Malaysia. Thus UF membrane study was conducted to investigate the effect of pressure and stirring speed on performance of POME treatment and fouling of membrane. Two types of membrane polyethersulfone (PES) and regenerated cellulose (RC) with molecular weight cut-off (MWCO) 5 and 10 kDa were used in this study. Results showed that, as pressure increased, fouling increased however permeate quality improved, the best pressure was 1.0 bar, where the fouling was not too high and produce good permeate quality. As stirring speed increased, fouling reduced and permeate quality improved, however, when stirring speed increased from 600 rpm to 800 rpm, there was no significant improvement on the permeate quality. Therefore, the best condition was at 1.0 bar and 600 rpm. PES membrane with MWCO 5 kDa showed the best permeate quality, even fouling slightly higher than RC membrane. The permeate quality obtained were analyzed in term of dissolved solid, turbidity, suspended solid, biological oxygen demand (BOD5) and chemical oxygen demand (COD) were 538 mg/L, 1.02 NTU, < 25 mg/L, 27.7 mg/L and 62.8 mg/L, respectively with dominant type of fouling is cake resistance. Thus, it can be concluded water reuse standard was successfully achieved in terms of BOD5 and suspended solid

Uniformity investigation of deposited nanoparticles via pulse direct current (DC) in electrophoretic deposition (EPD) / Rabiatul Adawiyah Abdol Aziz, Noor Fitrah Abu Bakar and Mohd Nazli Naim

Nowadays, with increasing thrust on nanostructured materials, Electrophoretic Deposition (EPD) technique is being viewed with more interest for assembly of nanoparticles. It covers a wide range of applications such as photonic materials, high density magnetic data storage devices, microchip reactors and biosensors. Obviously, the use of water/aqueous implies advantages such as a faster kinetics, in addition to important health, environmental, and cost benefits. However, it causes a number of problems in electrophoretic forming mainly related to electrochemical reaction in the electrodes when current is passed through, which seriously affects the efficiency of the process and the uniformity of the deposit. Different sizes of standard nanoparticles i.e. polystyrene latex (PSL) particles will be diluted with milipore water into several concentration media and it will be sonicated . pH of the aqueous will be prepared in acid and alkaline media by adding HCl and NaOH respectively. Carbon and copper electrode will be submerged in the media. EPD with Direct Current (DC) voltage will be applied during the deposition process. The deposited particle will be weighed with balancer. For the case of pulse DC, different frequency of pulse cycle will be applied. The deposited particles will be analyzed using X-ray Diffraction (XRD). The morphology of the deposited naoparticles will be analyzed by using Scanning Electron Microscopy (SEM). Distribution of the deposited particle will be characterized iether by using EDS analyzer in SEM. In this work, we propose to evaluate the uniformity of the deposited particles with EPD technique, pulse DC will be applied in the experiment with different frequency of pulse cycle

Cellulase production from treated oil palm empty fruit bunch degradation by locally isolated Thermobifida fusca.

The aim of this research was to evaluate the production of cellulases from locally isolated bacteria, Thermobifida fusca, using thermal and chemical treated oil palm empty fruit bunch (OPEFB) as substrate in liquid-state fermentation (LSF). T. fusca was successfully isolated and was a dominant cellulase producer in OPEFB composting at the thermophilic stage. Analysis of the surface morphology of OPEFB samples using Scanning Electron Microscopy (SEM) showed that the most significant changes after the combination of thermal and chemical pretreatment was the removal of silica bodies, and this observation was supported by X-ray Diffraction analysis (XRD), Fourier Transform Infrared (FTIR), and Thermogravimetric analysis (TG) showing changes on the hemicelluloses, cellulose, and lignin structures throughout the pretreatment process. As a result of the pretreatment, higher cellulase production by T. fusca was obtained. The highest activity for CMCase, FPase, and β-glucosidase using optimally treated OPEFB were 0.24 U/mL, 0.34 U/mL, and 0.04 U/mL, respectively. Therefore, it can be suggested that the combination of chemical and thermal pretreatments enhances the degradation of OPEFB for subsequent use as fermentation substrate, contributing to a higher cellulases yield by T. fusca

Enzyme Saccharification Of Oil Palm Mesocarp Fiber (OPMF) Treated With Superheated Steam.

The effectiveness of superheated steam pretreatment on the enzymatic saccharification of oil palm mesocarp fiber (OPMF) was investigated by varying the temperature (140 to 210 °C) and the retention time (20 to 90 minutes). The results showed that superheated steam pretreatment at 180 °C for 60 minutes is the optimum condition for enzymatic saccharification of OPMF. Scanning electron microscopy (SEM) images of the OPMF show that superheated steam pretreatment is able to remove silica bodies. Further characterization by FTIR and TG/DTG analysis of the raw and treated OPMF indicates that the solubilization and removal of hemicelluloses took place after the pretreatment. This suggested that superheated steam pretreatment is an effective method for the alteration of the OPMF structure and enhances the digestibility of the biomass, hence improving enzymatic saccharification