Khairuddin Sanaullah

Recent developments in immobilizing titanium dioxide on supports for degradation of organic pollutants in wastewater- A review

This review focuses on the various types of supports used for immobilization of titanium dioxide nanomaterial catalyst for degradation of organic pollutants in wastewater. Several supports suitable to particular immobilization technique used for the degradation of pollutants in wastewater streams are explained. In general, a coating of catalyst on supports is carried out either by physical (e.g., thermal treatment) or by chemical (e.g., sol–gel). Among a range of the supports used, some of the prominent ones include glass, silica, activated carbon, stainless steel, cellulose, clay. Also, characterization methods in use such as X-ray diffraction, transmission electron microscope, scanning electron microscope, and UV-spectroscopy are discussed. The operating parameters such as temperature for the selected immobilization techniques are also explained.

Modeling and optimization of photocatalytic treatment of pre-treated palm oil mill effluent (POME) in a UV/TiO2 system using response surface methodology (RSM)

Abstract This study aimed at the degradation of COD, BOD and Color present in palm oil mill effluent (POME) using UV/TiO2 system. A Statistical tool called face-centered central composite design has been run through response surface methodology by the use of design expert software to model and optimize the photodegradation process. The SEM average size of the synthesized TiO2 particle is 100 nm and this confirm that it is anatase. The prominent peak as reveal by XRD occur at 22.3° and this indicates that TiO2 formed is anatase. The FTIR results shows a peak value of 1,406.50 and 1,452.50 cm−1 indicating that the TiO2 anatase is formed while nonappearance of the peak at 2,900 cm−1 indicates that the all organic compounds have been removed after calcination. The three models developed for the three pollutants are non-significant as revealed from the Prob > F values of 0.0584 for COD, 0.0612 for BOD and 0.4239 for color and this confirms that proposed models fit the experimental data. The optimum conditions for the three parameters are 5.50 for initial pH, 4.84 mg for catalyst dosage and 42.86 min for time and the percentage removal of the COD, BOD, and color are within the range of 59.43–96.81%, 48.05–102.68% and 60.63–94.29% respectively. Regression analysis obtained through analysis of variance provided significant quadratic polynomial with the coefficient of determination R2 = 0.9646, 0.9496 and 0.9223 for COD, BOD, and Color removal respectively.

Adsorption Equilibrium for Heavy Metal Divalent Ions (Cu2+, Zn2+, and Cd2+) into Zirconium-Based Ferromagnetic Sorbent

Zirconium-based ferromagnetic sorbent was fabricated by coprecipitation of Fe2+/Fe3+ salts in a zirconium solution and explored as a potential sorbent for removing the Cu2+, Zn2+, and Cd2+ from aqueous solution. The sorbent could easily be separated from aqueous solution under the influence of external magnetic field due to the ferromagnetism property. A trimodal distribution was obtained for the sorbent with average particle size of 22.74 μm. The –OH functional groups played an important role for efficient removal of divalent ions. The surface of the sorbent was rough with abundant protuberance while the existence of divalent ions on the sorbent surface after the sorption process was demonstrated. Decontamination of the heavy metal ions was studied as a function of initial metal ions concentration and solution pH. Uptake of the heavy metal ions showed a pH-dependent profile with maximum sorption at around pH 5. The presence of the ferromagnetic sorbent in solution at different initial pH has shown a buffering effect. Equilibrium isotherms were analyzed using Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherm models. Adequacy of fit for the isotherm models based on evaluation of and ARE has revealed that heavy metal ions decontamination was fitted well with the Freundlich model.

Recent developments in bamboo fiber-based composites: a review

The dominant emerging materials from more than 30 years ago are plastics, ceramics, and composite materials. Composite materials have steady growth in the volume and number of its applications as it enviably penetrates existing markets while creating new ones. Contemporary composite materials are well established in today’s market of specialty and everyday products with its proven worth as weight-saving materials. There is a current challenge of cost-effectiveness and environmental friendliness, thus leading to the search for low-cost polymeric-reinforced composites using entirely biodegradable fibers. Bamboo fibers have provided some response in the production of materials that are recyclable, biodegradable, and sustainable. The natural fibers yield composites with high strength-to-weight ratios as a function of the best properties of each component. Researchers have found sustainable high-end quality industrial products that can be generated from raw materials like bamboo fibers. Due to its high strength-weight ratio, bamboo fibers are often used to replace natural glass fiber. Thus, the much attention has been given to its composites with different matrix materials. This article gives a review of recent developments of bamboo fiber-based reinforced composites, its processing methodology, and applications.

CFD based Hydrodynamic Parametric study of inclined injected Supersonic steam into subcooled water

Hydrodynamic parametric study of the supersonic steam injection into subcooled water is investigated.The phenomenon of direct-contact condensation, used in steam driven jet injectors, nuclear reactor emergency core cooling systems and direct-contact heat exchangers was investigated computationally by injecting an inclined steam jet without the presence of non condensable gases using a supersonic nozzle submerged in subcooled water. Ansys Fluent based Euler-Euler multiphase model is used. The angle of inclination is varied from 450 to 00 with a decrement of 200 for each computation with the constant inlet pressure of 7 bars and water temperature of 300C. It was found that the temperature and pressure near the nozzle exit showing an abrupt height with the instantaneous condensation upon venting. The hydrodynamic Gaussian profile width is more in the case of vertical injection as compare to the inclined injection which depict the effect of static water fluid pressure and gravity on pressure head and temperature.

Development of a Sensor to Detect Condensation of Super-Sonic Steam

This paper explains the development and functioning of AC driven electrodes based sensor which is used for the study of condensation phenomena of steam. Time for the AC signals starts form 20 msecond to 1 second. Data acquisition system is employed against each time interval and the output data is fed into EIDORS (a free software algorithm). Images show the clear boundaries between pure steam, its interface and water.

Inclined Injection of Supersonic Steam into Subcooled Water: A CFD Analysis

The phenomenon of direct-contact condensation gains attention because of various industrial applications; nuclear reactor emergency core cooling systems,steam driven jet injectors, direct-contact heat exchangers etc..The phenomenon was investigated computationally by injecting an inclined steam jet using a supersonic nozzle submerged in subcooled water. The condensation mechanism is based on two resistance model, which involves consideration of the heat transfer process on both sides of the interface along with use of a variable steam bubble diameter. For computations, ANSYS Fluent based Euler-Euler multiphase model is used. The angle of inclination varies from 5o to 45o at constant inlet pressure of 7 bars with water temperature of 30°C. The maximum penetration length is achieved using a right angled vertical injection.