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Properties Of Concrete

Economics of biodiesel production: Review

Polymers have been widely used in agriculture for applications including controlled release of pesticides and other active ingredients. The ability to predict their delivery helps avoid environmental hazards. Macromolecular matrices used as carriers in controlled release of agricultural active agents, especially pesticides, are reviewed. The review focuses on the advantages and mechanisms of controlled release. It includes biodegradable polymers in agriculture, their manufacturing methods, and their degradation mechanisms and kinetics. The article also presents a critical account of recent release studies and considers upcoming challenges.

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Controlled pesticide release from biodegradable polymers

Biodiesel is gaining attention as a remedy for the increasing demand of fossil fuels which is depleting rapidly. Commercial homogeneous catalysts in the biodiesel production industry are facing challenges such as separation difficulties and severe corrosion which will lead to the increment of production and maintenance cost. Herein, this paper focuses on the comprehensive review of literature reported on the usage of biomass as the precursor for the catalyst used in biodiesel production. Compared to other commercial catalysts, the usage of biomass as catalyst precursor possesses several advantages such as abundantly available, cheaper raw materials, reusable, non-toxic and biodegradable. Carbon material synthesized from biomass which acts as the efficient support for active sites due to its high porosity and surface area characteristic has been studied widely. The latest development of biomass derived basic, acidic and magnetic heterogeneous catalyst through several state of the art synthesis pathways starting from the synthesis of the supporting material (carbon) until the functionalization process to form the complete catalyst was reviewed. Apart from direct sulfonation using sulfuric acid, sulfonation by reduction and arylation were less hazardous and provided comparable active sites activity. Most biomass based catalysts exhibited good catalytic performance by providing high biodiesel yield of above 80% at optimum conditions. Besides that, various kinetic models developed from the reaction kinetic study catalyzed by biomass based catalyst were also reviewed as a preparatory stage for the scaled-up commercialization process of the studied catalyst in the biodiesel production sector. This catalyst could assist to lower the activation energy required for the reactions and thus enables higher reaction rate to reach equilibrium. Continuous research on producing high performing biomass based catalyst with minimum resources is needed in order to achieve the ultimate goal of green and sustainable biodiesel industry.

Synthesis of biomass as heterogeneous catalyst for application in biodiesel production: State of the art and fundamental review

Esterification of Palm Fatty Acid Distillate with High Amount of Free Fatty Acids Using Coconut Shell Char Based Catalyst

Problem statement: Microcapsule is one of important fine chemical pro ducts in the current chemical industries. Better understanding of microe ncapsulation process is useful to properly design o f microcapsule with specific characteristics. The aim of this research is to study the mechanism of Urea - Formaldehyde (UF) microcapsules formation. Approach: Microcapsule was prepared in two steps. The first step was the preparation of oil in water emulsion, which was carried out by mixing of UF pre- polymer solution with refined palm oil at 50-70°C, using high speed homogenizer. The second step was microcapsule shell formation, where the pH of e mulsion was adjusted to 3 and the process was run for 3-6 h. At the end of the process, the microcaps ule product was cooled with ice and distilled water , filtered, washed and finally dried at 40°C under va cuum condition. The diameter and size distribution of the microcapsule product was measured using optical microscope. Results: Microcapsule with the diameter of 20-220 µm, together with UF micro particles. Conclusion: UF polymerization reaction took place simultaneously in the solution and at th e microcapsule surface. UF reaction in the solution produced UF polymer micro particles, while UF reaction at the microcapsule surface forms microcapsule shell. The UF polymer micro particles precipitated in the form of fine powder, attach to the microcapsule shell. Higher microencapsulation t emperature reduced the amount of microcapsule product and increased the amount of micro particles . The microcapsule diameter distribution shifts to smaller diameter and the average diameter D avg tends to decrease as the homogenization and microencapsulation time increase. Based on oil and resin efficiencies as well as microcapsule characteristics, the process is best conducted at 5 0°C, 30 min of homogenization and 3 h of microencapsulation time.

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Mechanism of Microencapsulation with Urea-Formaldehyde Polymer

Characteristics of glucomannan isolated from fresh tuber of Porang (Amorphophallus muelleri Blume).

Esterification of Free Fatty Acid on Palm Fatty Acid Distillate using Activated Carbon Catalysts Generated from Coconut Shell

The catalytic cracking of nyamplung oil over ZSM-5 catalyst was investigated in a packed bed reactor at the temperature of 450 °C and ratio of catalysts to oils was 1:5. The results show that ZSM-5 has high selectivity for aromatics compounds but low in the paraffin compounds. This aromatic compound has an advantage in increasing the octane number of gasoline even though it should be limited due to environmental regulation. To upgrade the quality of the organic liquid product is done by modification catalyst. One of the method to modify the catalysts by impregnating metal Ni into ZSM-5 with various % weight of Ni (2-7 wt. %). From BET and BJH analysis shows that the modification Ni/ZSM-5 catalysts affected the surface area and pore volume of catalyst. Compared to catalytic cracking of nyamplung oil with ZSM-5 catalysts, the loading of Ni to ZSM-5 could improve the selectivity of paraffin compounds. Increasing on nickel loaded tends to increase the selectivity of paraffin compounds and decrease the aromatic compounds. But the addition of 2-7 wt. % Ni in the catalyst ZSM-5 has slightly affected the yield of liquid products. The yield of liquid products with catalyst ZSM-5 and Ni ZSM-5 in the range of 70-75%.

Effect of modification ZSM-5 catalyst in upgrading quality of organic liquid product derived from catalytic cracking of Indonesian nyamplung oil (Calophyllum inophyllum)

Rochmadi

Papers

Esterification of Palm Fatty Acid Distillate with High Amount of Free Fatty Acids Using Coconut Shell Char Based Catalyst

Mechanism of Microencapsulation with Urea-Formaldehyde Polymer

Characteristics of glucomannan isolated from fresh tuber of Porang (Amorphophallus muelleri Blume).

Esterification of Free Fatty Acid on Palm Fatty Acid Distillate using Activated Carbon Catalysts Generated from Coconut Shell

Effect of modification ZSM-5 catalyst in upgrading quality of organic liquid product derived from catalytic cracking of Indonesian nyamplung oil (Calophyllum inophyllum)