Amrifan Saladin Mohruni

Membrane Processing of Refined Palm Oil Wastewater Using TiO2 Entrapped Nanoporous PVDF Membrane

An explosive growth of interest has been developed in creating of alternative process of crude palm oil wastewater treatment. Membrane processing offers many advantages as it can be used in almost the stage of oily wastewater treatment. Aim of this study was to investigate nanoporous membrane morphology and performance for refined palm oil wastewater treatment. The comparison of performance and morphology was carried out between neat PVDF and PVDF nanoporous membranes with nanosized TiO2 particles of different compositions. Results of permeability and instrumental analysis illustrated that nanometer size obviously affected the PVDF membranes performance and structure. Smaller nanoparticles could improve the antifouling property of PVDF membrane more remarkably. Cross-section of membranes were observed with a field electronic scanning electron microscope (FESEM). The TiO2/PVDF membrane with smaller nanoparticles had smaller mean pore size on its surface and more apertures inside the membrane. X-ray diffraction (XRD) experiment was also suggested that the addition of 1.0 % TiO2 nanoparticles had stronger effect on crystallization of PVDF molecules, poresize of 34.05 nm, contact angle of 53o and flux of 88.50 L/m2h of poresize. It can be concluded that nanoporous PVDF membrane with adding of TiO2 has better performance for treating refined palm oil wastewater.

A comparison RSM and ANN surface roughness models in thin-wall machining of Ti6Al4V using vegetable oils under MQL-condition

Thin-wall components as usually applied in the structural parts of aeronautical industry require significant challenges in machining. Unacceptable surface roughness can occur during machining of thin-wall. Titanium product such Ti6Al4V is mostly applied to get the appropriate surface texture in thin wall designed requirements. In this study, the comparison of the accuracy between Response Surface Methodology (RSM) and Artificial Neural Networks (ANN) in the prediction of surface roughness was conducted. Furthermore, the machining tests were carried out under Minimum Quantity Lubrication (MQL) using AlCrN-coated carbide tools. The use of Coconut oil as cutting fluids was also chosen in order to evaluate its performance when involved in end milling. This selection of cutting fluids is based on the better performance of oxidative stability than that of other vegetable based cutting fluids. The cutting speed, feed rate, radial and axial depth of cut were used as independent variables, while surface roughness is evaluated as the dependent variable or output. The results showed that the feed rate is the most significant factors in increasing the surface roughness value followed by the radial depth of cut and lastly the axial depth of cut. In contrary, the surface becomes smoother with increasing the cutting speed. From a comparison of both methods, the ANN model delivered a better accuracy than the RSM model.Thin-wall components as usually applied in the structural parts of aeronautical industry require significant challenges in machining. Unacceptable surface roughness can occur during machining of thin-wall. Titanium product such Ti6Al4V is mostly applied to get the appropriate surface texture in thin wall designed requirements. In this study, the comparison of the accuracy between Response Surface Methodology (RSM) and Artificial Neural Networks (ANN) in the prediction of surface roughness was conducted. Furthermore, the machining tests were carried out under Minimum Quantity Lubrication (MQL) using AlCrN-coated carbide tools. The use of Coconut oil as cutting fluids was also chosen in order to evaluate its performance when involved in end milling. This selection of cutting fluids is based on the better performance of oxidative stability than that of other vegetable based cutting fluids. The cutting speed, feed rate, radial and axial depth of cut were used as independent variables, while surface roughness ...

Membrane technology for treating of waste nanofluids coolant: A review

The treatment of cutting fluids wastes concerns a big number of industries, especially from the machining operations to foster environmental sustainability. Discharging cutting fluids, waste through separation technique could protect the environment and also human health in general. Several methods for the separation emulsified oils or oily wastewater have been proposed as three common methods, namely chemical, physicochemical and mechanical and membrane technology application. Membranes are used into separate and concentrate the pollutants in oily wastewater through its perm-selectivity. Meanwhile, the desire to compensate for the shortcomings of the cutting fluid media in a metal cutting operation led to introduce the using of nanofluids (NFs) in the minimum quantity lubricant (MQL) technique. NFs are prepared based on nanofluids technology by dispersing nanoparticles (NPs) in liquids. These fluids have potentially played to enhance the performance of traditional heat transfer fluids. Few researchers have studied investigation of the physical-chemical, thermo-physical and heat transfer characteristics of NFs for heat transfer applications. The use of minimum quantity lubrication (MQL) technique by NFs application is developed in many metal cutting operations. MQL did not only serve as a better alternative to flood cooling during machining operation and also increases better-finished surface, reduces impact loads on the environment and fosters environmental sustainability. Waste coolant filtration from cutting tools using membrane was treated by the pretreated process, coagulation technique and membrane filtration. Nanomaterials are also applied to modify the membrane structure and morphology. Polyvinylidene fluoride (PVDF) is the better choice in coolant wastewater treatment due to its hydrophobicity. Using of polyamide nanofiltration membranes BM-20D and UF-PS-100-100, 000, it resulted in the increase of permeability of waste coolant filtration. Titanium dioxide is nanomaterials additive to modify the Nanopores of the surface membrane. Contact angle and average pore size were used in the investigation of the surface morphology of membranes. An adequate choice in modifying the membrane surface in waste coolant filtration may bring a promised alternative as a solution in waste coolant remediation.The treatment of cutting fluids wastes concerns a big number of industries, especially from the machining operations to foster environmental sustainability. Discharging cutting fluids, waste through separation technique could protect the environment and also human health in general. Several methods for the separation emulsified oils or oily wastewater have been proposed as three common methods, namely chemical, physicochemical and mechanical and membrane technology application. Membranes are used into separate and concentrate the pollutants in oily wastewater through its perm-selectivity. Meanwhile, the desire to compensate for the shortcomings of the cutting fluid media in a metal cutting operation led to introduce the using of nanofluids (NFs) in the minimum quantity lubricant (MQL) technique. NFs are prepared based on nanofluids technology by dispersing nanoparticles (NPs) in liquids. These fluids have potentially played to enhance the performance of traditional heat transfer fluids. Few researchers ha...

Mathematical Modelling of Surface Roughness on Tropical Wood Machining Using Response Surface Methodology

Surface roughness is an important indicator to assess the surface processing quality and has a decisive impact on the furniture finishing effects. In this research, the application of response surface methodology (RSM) has been carried out for modelling and analysing of influences in the sanding process on wood materials. Surface roughness parameter Ra showed surface characteristics of Tembesu, Jati and Petanang. This study is aimed to observe the effect of feed rate and grit size on Ra. The central composite design (CCD) was used as a design of experiment (DOE). There were 8 runs at factorial points and additional 5 replicated runs at the centre point. The sanding process was done using a modified horizontal milling machine. The results are statistically analysed by using Design Expert software. It was found that increasing of feed rate had a positive effect on the roughness value of Ra and greater feed rates increased the surface roughness. On the other hand, grit size influenced negative effect. Larger grit size affected the smoother surface roughness. At the end of this study, it was also revealed that the optimum machining conditions in terms of feed rate and grit size were 17 mm/min and 240 for Tembesu and Jati, while Petanang was 18.63 mm/min and 226.52.

An Investigation Effects of Electrospinning Parameters: Process Optimization by Application of Response Surface Methodology

Effects of material and process parameters on the electrospun polyacrylonitrile fibers were experimentally investigated. Response surface methodology (RSM) was utilized to design the experiments at the setting of solution concentration, voltage and the collector distance. It also imparted the evaluation of the significance of each parameter on pore size, contact angle, modulus young and clean water permeability. Effect of applied voltage in micron-scale fiber diameter was observed to be almost negligible when solution concentration and collector distance were high. However, all three factors were found statistically significant in the production of nano-scale fibers. The response surface predictions revealed the parameter interactions for the resultant fiber diameter, and showed that there is negative correlation between the mean diameter and coefficient of variation for the fiber diameters were in agreement with the experimental results. Response surfaces were constructed to identify the processing window suitable for producing nanoscale fibers. A sub-domain of the parameter space consisting of the solution concentration, applied voltage and collector distance, was suggested for the potential nano scale fiber production.