Onn Hassan

Influence of Different Ultrasonic Wave on Polymerization of Polyaniline Nanofiber

Ultrasonic polymerizations at various wave frequencies of 5-20 kHz were used to synthesize polyaniline (PANI) nanofibers. PANI was synthesized using hydrochloric acid (HCl) as a dopant and ammonium persulfate (APS) as an oxidant. The characteristics of PANI based on molecular structure of functional group and morphology were characterized by fourier transform infrared (FTIR) and transmission electron microscopy (TEM). TEM images of PANI nanofiber show a long nanofibers structure with average diameter of ~25 nm. The FTIR spectra were in acceptable range and confirmed the successful formation of PANI. In this study, the polymerization at frequency wave of 20 kHz shows the best overall properties of produced PANI nanofiber.

The application of first and second orders of inherent safety in the chemical process industry

The inherent safety (IS) concept has been introduced for more than 45 years, yet its adoption into process design is still very low. As a result, similar accidents keep on occurring worldwide since a majority of the risk reduction strategies used are based on the outer layers of protection such as active engineered and procedural. To enhance the uptake of inherent safety into chemical plant design, this paper aims to outline the common inherent safety strategies that have been used by the chemical process industry (CPI) to prevent accidents. 502 cases of inherently safer design (ISD) applications in the CPI have been collected and analysed. The process changes through plant modification are grouped based on the four main ISD strategies of minimisation, substitution, moderation, and simplification. The four main ISD keywords are then further classified into a hierarchy of inherent safety order. 58 cases (12 %) fall under first order IS which is from substitution keyword. For the 2nd order IS (magnitude), the keyword minimisation gives 242 cases (48 %) while moderation gives 151 (30 %). The simplification keyword which is under 2nd order IS (likelihood) gives 51 cases (10 %). The 2nd order IS (magnitude) seems to give the biggest numbers of design changes made by the CPI. Magnitude reduction strategy is the common choice by the CPI when designing safer equipment or process.

An Investigation into the Need of Process Safety Management (PSM) in the Palm Oil Industry

Palm oil industry (POI) is one of the major industries in Malaysia that contribute more than half of the Malaysia’s export value. Hence, the development of the industry also includes the well-being of the workers in the industry. As a consequence, the POI must adhere to several laws that provide protection for the workers’ safety and health such as OSHA 1994 and availability of guidelines to safety and health management such as OHSAS 18001. However, in terms of process safety, the POI is way lacking behind despite several incidents that show that POI as well is susceptible to process failures that lead to disastrous accidents. Process safety management has been successfully implemented in the chemical process industry (CPI) which is driven by the fact that the process is high risk with the utilization of hazardous materials and likelihood of fire and explosion. Hence, by comparison, it is found that these two industries has some similarity in terms of hazards, however the risk is found to be lower in the POI as compared to the CPI mainly because of the more hazardous materials that are involved in the CPI.

Evaluation of Palm Biodiesel - Diesel Blending Properties, Storage Stability and Corrosion Behavior

Palm Biodiesel, which can be produced from transesterification palm oil with methanol, is an alternative fuel for diesel engines. It can be mixed with diesel fuels and used in diesel engines with no or slight modification. Therefore, in this study, commercially available diesel fuel was blended with biodiesel produced from transesterification of palm oil. The stability of the pure palm biodiesel (B100) was investigated over a storage time of 2, 4 and 6 months. The study assessed the corrosion rate of metals exposed to palm biodiesel. The kinematic viscosity, density and flash points of the blends increased with biodiesel amount in the fuel blend. However, pour point of the blends decreased as the amount of biodiesel in the blends is increased. Kinematic viscosity, pour point and flash point slightly increased with storage time. The average corrosion rate for copper is 0.5341 mpy, 0.2438 mpy for aluminium and 0.1802 mpy for mild steel.