Volume 2 Issue 1
Authors: Mohamad Anuar Kamaruddin; Mohd Suffian Yusoff; Hamidi Abdul Aziz; Rasyidah Alrozi
Abstract: This study investigates the optimum preparation conditions for coconut shell activated carbon (CSAC) and clinoptilolite (Cl) composite adsorbent. The prepared composite adsorbent was tested towards color removal sourced from a textile waste water retention pond by batch test. Central composite design (CCD) was used to determine the effects of the two preparation variables CSAC and Cl on percentage color removal. The significant factors on each experimental design response were identified from the analysis of variance (ANOVA). The optimum preparation conditions for composite adsorbent were obtained by using CSAC and Cl of 5 and 63 by weight percent, respectively, which resulted in over 70% of color removal. The optimum content of OPC was found 25% from the total weight mixtures. In the other hand, 250 rpm shaking speed held the advantage to remove over 70% of colour concentration. Meanwhile, SEM image showed that the embedded Cl in the microstructure of composite adsorbent was clearly observed. A rod like arrangement clods distributed on the surface of the composite adsorbent implied that the suggested preparation conditions were adequate to embed the Cl onto the composite adsorbent mixture.
Keywords: Composite; Statistical Analysis; Coconut Sheel Activated Carbon; Clinoptilolite; Textile Wastewater
Authors: Farzaneh Fathi; Hassan Namazi
Abstract: This paper reports the synthesis of higher fatty acid esters (C8, C12, C16) of potato starch in the absence of organic solvents. The synthesis process is interesting and very convenient in which water is utilized as a nontoxic and a low-priced solvent. Starch dispersed in the reaction medium was alkali treated and then alkaline starch was esterified with using octanoyl, lauroyl and palmitoyl chloride. Esterification was readily carried out under an air atmosphere for reaction duration of 5–10 min. The results indicated that the degree of substitution of the starch esters diminishes with increase in fatty acid chain length. The chemical structural characteristics were investigated by FTIR. Surface morphology of modified starch was studied using scanning electron microscopy (SEM). Also X-ray diffraction studies showed that the starch crystalline structure has changed during reaction.
Keywords: Modified Starch; Fatty Acid; Esterification; Without Organic Solvents
Authors: Abu Baker Abdulrasheed; Abdullah I. A. Al-Aqel; Ahmad Kadhum Falih
Abstract: This paper presents the effect of polymer type and specimen size on the strength properties of concrete-polymer composite. The aim of this study is to determine the compressive strength and the stress-strain behavior of the test samples. Three different types of polymer are used; poly-propylene (PP), Low Density Polyethylene (LDPE), and Poly-VinylPyrrolidene (PVP), with different additives to modify the cement concrete matrix. By means of compressing loading method, the compressive strength and stress-strain properties of polymer modified concrete are measured. The effect sample thickness on the mechanical properties is also investigated. The results demonstrated that the polymer-modified concrete, made with a hybrid layer of (PP+PE) shows maximum enhancement in tensile stress and ultimate strain with ratio about 42% , and 33% respectively. The results show that The compressive strengths of polymer concrete composite were not enhanced by the addition of (PVP) fine powder.
Keywords: Concrete-polymer Composite; Compressive Strength; Fracture Toughness