Ismail Abustan

Bio: Ismail Abustan is an academic researcher from Universiti Sains Malaysia. The author has contributed to research in topics: Groundwater & Adsorption. The author has an hindex of 25, co-authored 122 publications receiving 1571 citations. Previous affiliations of Ismail Abustan include Universiti Teknologi Malaysia & Universiti Sains Malaysia Engineering Campus.

A review: production of activated carbon from agricultural byproducts via conventional and microwave heating

Abstract: Productionofactivatedcarbon(AC)fromagriculturalbyproductsis a researchfieldthathas gainedincreased interestin recent years because of its potential for the disposal of agro-residues. At the same time, a beneficial byproduct that can be used in a number of environmental applications is produced. This paper surveys the developments in the production processes of AC fromagriculturalbyproductsinthepast7yearsfrom2005to2012viaconventionalandmicrowaveheating.Emphasisisplaced on the applied methodology and the influences of activating conditions, such as carbonization temperature, retention time, and impregnation ratio. From the review of AC production processes, agricultural wastes produced by a chemical method with microwave heating can be a source of AC with relatively higher surface area than that produced via conventional heating. c � 2013 Society of Chemical Industry Supportinginformationmaybefoundintheonlineversionofthisarticle.

Cadmium removal from aqueous solution using microwaved olive stone activated carbon

Abstract: Contamination of natural aquatic ecosystems by wastewater containing heavy metals is a major environmental and human health issue. The removal of heavy metals using adsorption techniques with microwave-irradiated low-cost adsorbents has a few numbers of studies. In this study, the removal efficiency for cadmium (Cd2+) from aqueous solution using olive stone activated carbon (OSAC) prepared by microwave was investigated. Central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the interaction and relationship between operating variables (i.e., radiation power, radiation time, and impregnation ratio), and to develop the optimum operating condition. Equilibrium isotherms in this study were analyzed using the Langmuir and Freundlich. Kinetic data were obtained and analyzed using pseudo-first-order and pseudo-second-order equations. Based on statistical analysis, Cd2+ removal model proved to be significant with very low probability values (

Kinetics and equilibrium adsorption of iron (II), lead (II), and copper (II) onto activated carbon prepared from olive stone waste

Abstract: The adsorption of heavy metals Fe2+, Pb2+, and Cu2+ onto olive stone activated carbon (OSAC) was investigated in this study. The effects of different reaction parameters (i.e. adsorbent dosage, contact time, shaking speed, and initial pH) on the pollutant removal efficiency were determined. The adsorption processes of Fe2+, Pb2+, and Cu2+ were effectively explained using Langmuir and Freundlich isotherms. OSAC efficiently removed 99.39% Fe2+, 99.32% Pb2+, and 99.24% Cu2+ at pH 5 and with 200 rpm shaking speed. The adsorption equilibrium data were best represented by the Langmuir model, and the monolayer adsorption capacities were found to be 57.47, 22.37, and 17.83 mg/g for Fe2+, Pb2+, and Cu2+, respectively. A pseudo-second-order model sufficiently described the adsorption kinetics, which indicated that the adsorption process was controlled by chemisorption. The results revealed that OSAC can be used as a low-cost adsorbent for the treatment of wastewaters contaminated by heavy metals.

Applying Minimum Night Flow to Estimate Water Loss Using Statistical Modeling: A Case Study in Kinta Valley, Malaysia

Abstract: Minimum night flow (MNF) is a common method used to evaluate water loss in a water network. In 2010, the average percentage of non-revenue water for the state of Perak in Malaysia was 29.4 %, a figure which resulted in major financial, supply, and pressure losses, as well as excessive energy consumption. In this study, a statistical analysis of the water distribution network and a modeling of MNF were carried out to estimate water loss in Kinta Valley, Perak. Flow and pressure for 361 zones were monitored for 24 h using PrimeWorks software (version: 1.5.57.0). Thirty study zones were randomly selected from 361 zones. MNF was screened within the time band of 1:00 am to 5:00 am. A total of 20 factors for physical, hydraulic, and operational variables were selected and correlated with MNF (L/s). Multiple linear regression was used as a statistical technique to determine factors that contributed to MNF (L/s). Consequently, pipe length (m) and pipe age (year) were the main contributors to MNF (L/s). The statistical model was finalized with R-Sq 0.706 and then improved to R-Sq 0.779. Results of the study revealed that 84.9 % of MNF frequencies for the 30 study areas were found at the time band 2:15 am to 4:15 am; therefore, the mean MNF for each zone in 2010 was determined to be between 1:00 am and 5:00 am. Statistical analyses showed that number of connections, total length of pipe, weighted mean of age of pipe, and type of pipe (100 mm asbestos cement) contributed to MNF. Moreover, approximately 97.5 % of registered repairs were conducted on pipes with small diameters of less than or equal to 50 mm. Pipes within this size range are usually used as service pipes and service connections.

Application of response surface methodology (RSM) for optimization of Cu2+, Cd2+, Ni2+, Pb2+, Fe2+, and Zn2+ removal from aqueous solution using microwaved olive stone activated carbon

Abstract: BACKGROUND The efficiencies of removal of Cu2+, Cd2+, Ni2+, Pb2+, Fe2+, and Zn2+ from aqueous solution with olive stone activated carbon (OSAC) were investigated in this work. A central composite design (CCD) method was used to optimize the preparation of OSAC using microwave assisted potassium hydroxide. RESULTS The optimum conditions obtained were 565 W radiation power, 7 min radiation time, and 1.87 impregnation ratio. This resulted in 98.55% removal of Cu2+, 95.32% of Cd2+, 98.19% of Ni2+ 98.83% of Pb2+, 99.32% of Fe2+, 98.36% of Zn2+, and 85.15% of OSAC yield. The surface characteristics of the AC prepared under optimized conditions were examined by pore structure analysis, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The BET surface area, total pore volume and average pore diameter of the prepared AC were 1280.71 m2 g−1, 0.604 cm3 g−1 and 4.63 nm, respectively. The equilibrium data of the adsorption was well fitted to the Langmuir equation and the highest value of adsorption capacity (Q) on the OSAC was found for Fe2+ (62.50 mg g−1), followed by Pb2+ (23.47 mg g−1), Cu2+ (22.73 mg g−1), Zn2+ (15.08 mg g−1), Ni2+ (12.00 mg g−1), and Zn2+ (11.72 mg g−1). CONCLUSIONS OSAC prepared by microwaves can be used for the removal of metals from contaminated wastewater. © 2013 Society of Chemical Industry

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Textile dye wastewater characteristics and constituents of synthetic effluents : a critical review

Abstract: Textile industries are responsible for one of the major environmental pollution problems in the world, because they release undesirable dye effluents. Textile wastewater contains dyes mixed with various contaminants at a variety of ranges. Therefore, environmental legislation commonly obligates textile factories to treat these effluents before discharge into the receiving watercourses. The treatment efficiency of any pilot-scale study can be examined by feeding the system either with real textile effluents or with artificial wastewater having characteristics, which match typical textile factory discharges. This paper presents a critical review of the currently available literature regarding typical and real characteristics of the textile effluents, and also constituents including chemicals used for preparing simulated textile wastewater containing dye, as well as the treatments applied for treating the prepared effluents. This review collects the scattered information relating to artificial textile wastewater constituents and organises it to help researchers who are required to prepare synthetic wastewater. These ingredients are also evaluated based on the typical characteristics of textile wastewater, and special constituents to simulate these characteristics are recommended. The processes carried out during textile manufacturing and the chemicals corresponding to each process are also discussed.