Noorhisham Tan Kofli

Isotherm equilibria of Mn2+ biosorption in drinking water treatment by locally isolated Bacillus species and sewage activated sludge

Manganese (Mn(2+)) is one of the inorganic contaminant that causes problem to water treatment and water distribution due to the accumulation on water piping systems. In this study, Bacillus sp. and sewage activated sludge (SAS) were investigated as biosorbents in laboratory-scale experiments. The study showed that Bacillus sp. was a more effective biosorbent than SAS. The experimental data were fitted to the Langmuir (Langmuir-1 & Langmuir-2), Freundlich, Temkin, Dubinin-Radushkevich (D-R) and Redlich-Peterson (R-P) isotherms to obtain the characteristic parameters of each model. Mn(2+) biosorption by Bacillus sp. was found to be significantly better fitted to the Langmuir-1 isotherm than the other isotherms, while the D-R isotherm was the best fit for SAS; i.e., the χ(2) value was smaller than that for the Freundlich, Temkin, and R-P isotherms. According to the evaluation using the Langmuir-1 isotherm, the maximum biosorption capacities of Mn(2+) onto Bacillus sp. and SAS were 43.5 mg Mn(2+)/g biomass and 12.7 mg Mn(2+)/g biomass, respectively. The data fitted using the D-R isotherm showed that the Mn(2+) biosorption processes by both Bacillus sp. and SAS occurred via the chemical ion-exchange mechanism between the functional groups and Mn(2+) ion.

Effective microbes for simultaneous bio-oxidation of ammonia and manganese in biological aerated filter system

This study determined the most effective microbes acting as ammonia-oxidising (AOB) and manganese-oxidising bacteria (MnOB) for the simultaneous removal of ammonia (NH(4)(+)-N) and manganese (Mn(2+)) from water. Two conditions of mixed culture of bacteria: an acclimatised mixed culture (mixed culture: MC) in a 5-L bioreactor and biofilm attached on a plastic medium (stages of mixed culture: SMC) in a biological aerated filter were isolated and identified using Biolog MicroSystem and 16S rRNA sequencing. A screening test for determining the most effective microbe in the removal of NH(4)(+)-N and Mn(2+) was initially performed using SMC and MC, respectively, and found that Bacillus cereus was the most effective microbe for the removal of NH(4)(+)-N and Mn(2+). Moreover, the simultaneous NH(4)(+)-N and Mn(2+) removal (above 95% removal for both NH(4)(+)-N and Mn(2+)) was achieved using a biological aerated filter under various operating conditions. Thus, the strain could act as an effective microbe of AOB and a MnOB for the simultaneous removal of NH(4)(+)-N and Mn(2+).

Comparative study between open ended laboratory and traditional laboratory

The traditional laboratory work based on guided assignment will not be adequate within the outcome based learning environment. Innovative approaches that require active involvement of the students in the learning activities are necessary in ensuring that the targeted learning outcomes are achieved. The Department of Chemical and Process Engineering, Universiti Kebangsaan Malaysia, introduced open ended laboratory work in 2008 as part of the effort to provide suitable learning environment for the students to achieve the learning outcomes. This paper describes a comparison study between traditional and open ended laboratory; the implementation of the open ended laboratory and its impact on the overall students learning experience with emphasis on programme outcomes. The open ended laboratory assignment was first implemented in the first semester of the 2008–2009 academic years. The students are divided in groups of four and were only given a statement on their laboratory assignment. They are required to determine the objectives and the scope of the laboratory assignment, to identify the necessary apparatus and prepare the step by step methodology. Each group is required to prepare a report on the above elements and present the results. They are graded based on the originality of their idea, results and discussion from the laboratory assignment and oral presentation. Initially the students had some difficulties because they were not familiar with such laboratory assignment. However, the performance was improved in the proceeding semesters and they are better prepared for their final year research project.

Recognition of Relevant ORP, pH, and DO Bending Points in Ammonia Removal from Drinking Water through Online BAF System

This study was undertaken to identify the relevant bending points in ORP, pH, and DO profiles in ammonia removal through online monitoring. A novelty BAF system as newl application for drinking water treatment that equipped with ORP, pH, DO and sensors was used. Two types of polluted drinking water strength (low and high strength) with various concentrations and aeration flow were treated at a fixed-time reaction of 24 h. Experiments were conducted at four track studies (TS) of TS1 ( 50 mg/L, aeration 0.3 L/min), TS2 ( = 100 mg/L, aeration 2.0 L/min), TS3 ( 100 mg/L, no aeration) and TS4 ( 10 mg/L, aeration 0.1 L/min). The results showed that the removal of was more than 95% for TS1, TS2, and TS4. From the online monitoring performances, DO elbow and ammonia valley appeared in ORP and pH profiles, respectively. Similarly, new positive plateaus were observed in DO, indicating that the nitrifiers stopped to consume the DO after was completely removed. Hence, based on the bending points, the aeration system is possible to be automatically stopped just after DO elbow and ammonia valley appears in order to save the energy consumption and to shorten the time demands for the drinking water treatment process.

Removal of ion in drinking water treatment using locally isolated heterotrophic nitrifier

ABSTRACT Batch removal treatment of from drinking water was carried using locally isolated heterotrophic nitrifier of Bacillus cereus I6. This work investigates the effect of initial concentration (5–25 mg/L), initial pH (pH 3–10) and inoculum size (0.5–3.0% v/v) on the removal of . From the isolation, screening and identification, heterotrophic B. cereus I6 (98% similarity) was the most potential degrading strain in removal. The removal was high at initial concentration of 5 mg/L (62%), initial pH of 5 (69.5%) and inoculum size of 3.0% v/v (85%). The removal decreased from 62 to 24.8% when the initial concentration was increased, while it had increased from 29 to 85% when the inoculum size was being increased. The most suitable conditions for removal by heterotrophic of B. cereus I6 was observed at an initial pH of 5.

Probiotic potentials of Lactobacillus plantarum isolated from fermented durian (Tempoyak), a Malaysian traditional condiment

Abstract Lactic acid bacterium isolated from fermented durian (tempoyak) was investigated for its potentials as a probiotic strain. Bacterial tolerance toward gastrointestinal environment, adhesion, and cytotoxic activity in human colon adenocarcinoma cell line HT‐29 was evaluated. 16S rRNA sequencing identified the lactic acid bacterium as Lactobacillus plantarum. The bacterium demonstrated good tolerance toward gastrointestinal pH 2.0 and 0.3% bile salts. It showed strong adhesive capacity in human intestinal cell line, HT‐29, with an adhesion index of 159 ± 10. Cytotoxicity of L. plantarum was investigated using both live bacterial cells (BC) and cell‐free supernatant (CFS). Findings showed that both BC and CFS of L. plantarum reduced proliferation of HT‐29 colon adenocarcinoma cells using MTT assay. The results imply potential probiotic properties of L. plantarum isolated from tempoyak.

Programme outcomes year III student through integrated project and open ended laboratory

In the Outcome Based Education curriculum, a student is expected to achieve the Programme Outcomes, (PO) upon graduation and the achievement of the programme outcomes have to be assessed through designated measurement methods. These POs were determined by the departmental review committee for the Outcome Based Education (OBE) and curriculum as well as feedbacks from various stakeholders (i.e. employers, alumni, parents etc.). In July 2012, Engineering Accreditation council, EAC has come out with new changes in their manual and dramatic change has been introduced on programme outcomes. Due to these changes, the department has taken proactive steps in efforts to fulfill the requirements of new 12 Pos. In an effort to assess the PO achievements, a few means were employed to collect data qualitatively and quantitatively. Among the steps taken are: Employer evaluation during industrial training, Alumni Survey, Exit Survey, Integrated project (IP), Open Ended Laboratory (OEL), Final Year Design Project, Final Year Research Project and formative assessment on course outcomes (before and after). In this paper, the assessments of PO Year III student through IP and OEL are elaborate in detail. The PO measure in IP are PO1 until PO11 excluding PO4 and PO12 whereas for OEL measure PO1, PO2, PO3, PO4, PO9, PO10 and PO11. Marks ≥ 50% obtained is an indicator of achievement of the PO obtained from Integrated Project and Open Ended Laboratory. The result shows that achievement of PO was at 50% and above for all measured POs.

Engineering Analysis in Co-Curricular Student Program of Chem E Car

Chem-E-Car is a group co-curricular activity among students in Chemical and Biochemical Engineering in the form of a competition. This activity gives students an opportunity to design and construct a mini vehicle powered by chemical energy source, i.e. chemical reaction, which will carry a specified load over a given distance. The competition also gives students the opportunity to practice their chemical engineering knowledge during class session. In this competition, the analysis of chemical reaction engineering is required to predict the movement of the car with a certain distance to carry the specific load of water volume. Generally, the competition is divided in two main categories such as poster presentations and car performance. For the poster presentation category, judges will evaluate mainly on soft skills either in individually or group. This paper focuses on the category of design and car performance including the car concept, implementation and chemical reaction mechanisms used in Universiti Kebangsaan Malaysia (UKM) level. In order to achieve a good car performance, an engineering analysis will help the group in determining the impact of car design and reaction mechanisms as the power source to move the car at a specific target.

Estimation of Bioethanol Production from Jatropha curcas Using Neural Network

Fossil fuel is one of the main energy sources for almost all country in the world. However, it is non-renewable energy source, not environmental friendly and the limited supply of the fossil fuel encouraged the scientist to discover other alternative way of new renewable energy supply. New alternative source should be considered for prolonged lifetime. Thus, non-conventional energy sources should be placed in the prior consideration, for instant bioethanol. Jatropha curcas seed is a toxic substance; however, it has a very high oil content which is approximately 3545%. After the extraction of oil from the seed, Jatropha seed cake is formed. In the pressed seed cake, it is found that it contains cellulose and glucose that can be used as substrate in bioethanol production. The production of bioethanol can be estimated by neural network using data from previous research. A programme using MATLAB 7.8 was used to develop the neural network. The software consists of Neural Network Toolbox which functions to train the input data and estimate the production of glucose and bioethanol as output data. An input layer represents the criteria of the production properties of glucose and bioethanol concentration. The hidden layer determines either the input data can be proceed to further production of glucose and bioethanol, whereas the output layer gives the estimation values of glucose and bioethanol production. Back propagation algorithm with TANSIG transfer function was used to accomplish the estimation of production of bioethanol. The error value given by the network was 0.0390. Thus, training sessions were considered successful. Therefore, the users could determine and estimate the production of glucose and bioethanol concentration in just a short period of time.