Simulation of biodiesel production through heterogeneously catalysed transesterification of vegetable oil by calcium ethoxide

Biodiesel is a clean burning alternative fuel, produced from domestic, renewable resources such as plant oils, animal fats, used cooking oil and even new sources such as algae. Biodiesel is also defined as fuel which has the same characteristics with commercial diesel in terms of its molecular formula. The transesterification reaction can be carried out using both homogeneous (acid or base) and heterogeneous (acid, base, or enzymatic) catalyst. Homogeneous catalysts provide much faster reaction rates than heterogeneous catalysts, but it is considerably more costly to separate homogenous catalysts from the reaction mixture (Liu et al., 2008). Therefore, heterogeneously base catalysts are studied in this research. The objective of this study is to find the feasibility of new type of heterogeneous catalyst in determining the best operating parameters and design factors which affecting the performance of biodiesel production. Aspen Plus 12.1 is used to performed the simulation study for feasibility of the biodiesel production using heterogeneous catalyst through a plug flow reactor (PFR). The simulation was done by incorporating the reaction kinetics and thermodynamics model into the reactor model. The NRTL of thermodynamics model is used in this research in order to perform the separation process for two liquid phases in the transesterification of vegetable oil process. The simulation was run after all the important property data had been incorporated into Aspen Plus simulator. After running all the operating parameters, it shows that the best temperature is 65 0C, the best molar ratio of methanol to oil is 6:1, the best mass ratio of catalyst to oil is 3% and the best space velocity is 0.25 hr-1 on oil conversion and biodiesel yield percentage. The PFR reactor schemes which are in single PFR, two PFR in series and PFR to CSTR were proposed as a suitable scheme for the production of biodiesel. Hence that, at the optimum operating condition, the conversion is 91.5%

Gallic Acid as a Potential Substitution for Phenol in Phenol-Formaldehyde Resin for Biocomposite Matrices

This project explores the production of new resins using gallic acid (GA) as a substitute for phenol in phenol-formaldehyde (PF) resin. A special curing schedule was made tailored to the limitations of the equipment used. Phenol was substituted with GA at various contents until the optimum ratio has been reached, which in this present study is 31% of gallic acid. The effects of co-reaction of GA and phenol with formaldehyde on mechanical, thermal, chemical and morphological properties were investigated. Test specimens were prepared by synthesising the pre-polymer at certain processing conditions and curing it in the autoclave. From the flexural test, addition of GA showed improvement in the flexural modulus and strength. The thermal properties of PF resin and GA resin were investigated by Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analysis (DMA) and Thermogravimetry Analysis (TGA). From the DSC result, no residual exotherm can be seen below 150 ℃ which indicates that the resin is suitable for use in natural fibre composites. Glass transition temperature (Tg) from DMA suggest that substitution of phenol with GA in production of resol resin has increased the glass transition temperature while TGA results showed that increasing GA substitution level in the compound resulted in increasing weight loss at lower temperature, and hence lower thermal stability. Based on Scanning Electron Microscopy (SEM) analysis, the flexural fracture surfaces for PF and GA resin displays no bubbles and voids present in the resin. It shows that the cure cycle proved to be successful in producing bubble-free specimens. In this study, Group Interaction Modelling (GIM) was also used to predict the Tg of the resin, which compares very well with the experimental work. Following the successful production of resin, nettle fibre was added as a reinforcing agent in producing the biocomposites. It shows that up to certain amount of nettle fibres, which is in this study 15 wt% of nettle fibres, the mechanical properties of the resin improved substantially. However, in composite systems, we can see particles and holes where fibres have pulled out upon fracture are clearly visible in the SEM images, which indicates poor interaction between fibre-matrix

Effect of ammonium polyphosphate on flame retardancy, thermal stability and mechanical properties of alkali treated kenaf fiber filled PLA biocomposites

In present research polylactic acid (PLA) biocomposites were prepared from PLA and kenaf fiber using dry blending, twin screw extrusion and compression molding techniques. PLA was blended with kenaf core fiber, polyethylene glycol (PEG) and ammonium polyphosphate (APP). Kenaf fiber was treated with 3%, 6% and 9% NaOH solution separately. Both raw and treated kenaf along with 10, 15 and 20 phr APP was utilized during composite preparation. The effects of APP content and alkali treatment on flammability, thermal and mechanical properties of kenaf fiber filled PLA biocomposites were investigated. APP is shown to be very effective in improving flame retardancy properties according to limiting oxygen index measurement due to increased char residue at high temperatures. However addition of APP decreased the compatibility between PLA and kenaf fiber, resulting in significant reduction of the mechanical properties of PLA biocomposites. Thermogravimetric analysis (TGA) showed that NaOH treatment improved the thermal stability of PLA biocomposites and decreased carbonaceous char formation

Determinants of attitude towards credit card usage

Credit cards have been viewed as a competitive banking product that helps to improve a bank’s financial position while at the same time improving financial transactions among customers of a bank. The present study explores the factors influencing the attitude of bank customers in the context of the Malaysian banking system. The study examines the effects of knowledge, media awareness, perceptions, family influence and religious factors on attitudes towards credit card usage. The study finds that knowledge, media awareness, perceptions and family influence are instrumental in determining consumer attitudes toward credit card usage. In more detail, perceptions are ranked highest, followed by family influence and knowledge. Identifying such factors helps to provide better information to direct future planning of credit card services. Importantly, this study provides valuable insight for bank managers to effectively oversee credit card services

PLA/Kenaf/APP biocomposites: effect of alkali treatment and ammonium polyphosphate (APP) on dynamic mechanical and morphological properties

Kenaf-filled polylactic acid (PLA) biocomposites were prepared using dry blending, twin screw extrusion and compression molding. PLA was blended with raw and alkali treated kenaf, polyethylene glycol and ammonium polyphosphate (APP). Dynamic mechanical properties of biocomposites were investigated by dynamic mechanical analysis. Storage modulus of composites decreased, while magnitude of damping peaks increased with increase in APP content. The T g of composites shifted to lower values with APP addition. Alkali treatment improved interfacial adhesion between PLA and kenaf. SEM analysis indicates good dispersion of APP in PLA matrix, however interfacial adhesion between PLA and matrix decreased with increasing APP content

VISUALISASI VARIASI MOTIF SONGKET SAMBAS MENGGUNAKAN METODE L-SYSTEM DAN HIMPUNAN JULIA

Songket Sambas merupakan salah satu seni budaya Indonesia yang menjadi ciri masyarakat Sambas. Songket Sambas memiliki motif yang menonjol yaitu motif pucuk rebung dihias dan ditaburi motif flora dan fauna. Pola simetris dan pengulangan bentuk pada motif songket dapat digambarkan secara fraktal. Fraktal adalah suatu bentuk geometris yang dapat dipisahkan ke dalam beberapa bagian, dimana masing-masing bagian itu merupakan versi kecil yang berulang. Motif fraktal dapat dibentuk dengan hitungan matematis dan divisualisasi menjadi gambar tertentu menggunakan metode L-System dan himpunan Julia. L-System dibangkitkan dengan segmen garis. Sedangkan himpunan Julia dibangkitkan dengan memanfaatkan bentuk rekursif dari suatu fungsi kuadrat yang melibatkan variabel dan parameter bilangan kompleks. Penelitian ini bertujuan untuk memperoleh motif fraktal songket Sambas tabur awan menggunakan metode L-System dan himpunan Julia. Hasil dari penelitian ini diperoleh bahwa songket Sambas tabur awan dapat dibentuk dari delapan motif untuk metode L-System dan satu motif himpunan Julia. Kata kunci: fraktal, songket, L-System, himpunan Juli

Pengaruh Keaktifan Masyarakat Dalam program Bank sampah Terhadap tingkat kesejahteraan

Community activity in the waste bank program is very important in addition to increasing public awareness in protecting the environment but also influencing the level of community welfare. If the community does not actively participate in the Waste Bank program, waste processing will experience obstacles, and can cause environmental problems caused by waste such as floods that can interfere with daily activities. These obstacles can affect the level of community welfare. The purpose of this study is to determine the effect of community activity in the Waste Bank program on the level of welfare. The research was carried out in Mulyasari Village, Tawang District, Tasikmalaya City. This study uses a quantitative approach with a sample size of 14 respondents. The results of the descriptive research show that there is a significant effect between the dependent variable on the independent variable. The conclusion generated is based on the results of the study that there is a positive and significant influence between community activities in the Waste Bank program on the level of community welfare. This is indicated by the value in the result of the sig value. ,000 < 0.05. This means that the higher community activity in the Waste Bank program, the level of community welfare will increase

A narrative review on modern wound dressing for diabetes mellitus wound

Introduction: Diabetic foot is a wide-ranging term for foot disorders includes infection, ulceration, or destruction of deep tissue due to peripheral neuropathy and ischemia from peripheral vascular disease. Wound dressings play a significant part in the treatment of diabetic foot ulcer (DFU). Modern wound dressing which is commonly known as the moist wound dressing can be better optional than the conservative one for the DFU. Aim: This study aimed to review the available articles on modern wound dressing for diabetes mellitus wound. Method: A total of six articles were reviewed and explained under the findings and discussion part of this study. The published articles from the year 2008 onwards are included in this narrative review. Result: Overall, it is evident that using of modern wound dressing can make sure excellent wound surroundings, avoid complications, improvement of quality of life of patients and aid the healing of DFU providing that the patient’s glycemic level is controlled. Conclusion: The process of wound healing in DFU is not static and it requires an appropriate environment at each stage of the healing process. And also a reasonable approach to the selection of dressing for certain types of wounds should be clarified. However, further study needs to be carried out to prove the current finding