Percentage Of Activated Carbon Research Articles

Effect of waterborne epoxy resin sizing on the surface and properties of high‐strength‐high‐modulus polyimide fibers

AbstractTo improve the interface adhesion between high‐strength‐high‐modulus polyimide (PI) fibers and epoxy resin (EP) matrix, waterborne epoxy resin (WEP) sizing agents are used to modify the surface of PI fibers. The sizing treatment of PI fibers was carried out by the self‐made sizing machine, and the effect of WEP sizing concentrations on the structure and properties of PI fibers were discussed in detail. The surface roughness, activated carbon percentage, and surface energy of WEP‐sized PI fibers increased with increasing WEP sizing agent contents. While, the mechanical and thermal properties of WEP‐sized PI fibers decreased slightly with the increment of WEP sizing agent concentrations. The optimum WEP sizing concentration was recognized to be 2 wt%. The interfacial shear strength and the interlinear shear strength values of PI fibers and epoxy resin (PI/EP) composites were improved by 175.22 and 25.31%, respectively. Moreover, the mechanism of surface characteristic improvement with WEP sizing treatment were proposed, contributing to the enhancement of mechanical interlocking and chemical interaction between fibers and matrix.

STUDY PORE CHARACTERIZATION OF γ-ALUMINA – ACTIVATED CARBON COMPOSITE MADE OF CASSAVA PEELS (Manihot esculenta Cranz)

<p>A composite of γ-alumina and activated carbon made of cassava peels was studied in terms of its pore structures and its properties. The objective of this study was to determine the interaction and structure, as well as the character and pore size of γ-alumina – activated carbon composite.</p><p>Carbon made of cassava peels was activated by H<sub>2</sub>SO<sub>4</sub> and its activities were tested according to the Indonesian Industrial Standards (SII). The addition of activated carbon into γ-alumina made in variations of 10, 20, 30, 40 and 50 % w/w, of the total weight of 10 grams. The composite of γ-alumina - activated carbon was characterized by FTIR, SAA (Surface Area Analyzer), XRD, and determination of Hysteresis Loop composites.</p>The greater addition of activated carbon to γ-alumina causes intermolecular interactions between –O-H groups form rehydrated hydrogen bonds in the composite is greater. The structure of γ-alumina in the composites remain intact although the percentage of activated carbon in composite is large. The total pore volume and surface area using the BET method of the composite decreases with increasing activated carbon percentage. The greater addition of activated carbon to γ-alumina causes size of mesoporous composites decreased with the characteristic of a composite formed is closer to the activated carbon.

Removal of dioxins and PCB from fish oil by activated carbon and its influence on the nutritional quality of the oil

AbstractFish oils are well‐known sources of nutritionally valuable components such as the n‐3 FA EPA and DHA as well as the fat‐soluble vitamins A, D, and E. However, some fish oils can be contaminated with considerable amounts of dioxins and dioxin‐like PCB. The most important challenge during fish oil refining is to remove these contaminants without altering the levels fining is to remove these contaminants without altering the levels of nutritionally valuable compounds and the oxidative status and stability of the oil. Treatment with an apolar adsorbent, e.g., activated carbon (AC), seems to be the most efficient process today. Very little information about the adsorption of different dioxin and PCB congeners is available. Four grades of AC were evaluated for their efficiency in removing these compounds. In addition, the effects of the treatment on the nutritional and oxidative quality of the oil were evaluated. After treatment of contaminated cod liver oil [5.4 ppt toxic equivalents (TEQ) polychlorinated dibenzo‐p‐dioxins and dibenzofurans (PCDD/F), 18.1 ppt TEQ dioxin‐like PCB] with 0.5% AC, almost all PCDD/F and up to 80% of the dioxin‐like PCB could be removed. AC showed low affinity for mono‐ortho PCB (<30% removal), which could be explained by their noncoplanar structure. Removal efficiencies were dependent on the grade and percentage of AC used. The treatment of contaminated cod liver oil caused no important effects on oil quality or FA composition in the conditions tested.