Riau University

About: Riau University is a education organization based out in Pekanbaru, Indonesia. It is known for research contribution in the topics: Population & Government. The organization has 4135 authors who have published 3895 publications receiving 15782 citations.

Solid heterogeneous catalysts for transesterification of triglycerides with methanol: A review

Abstract: Increasing number of researches focusing on the use of solid heterogeneous catalysts for the production of biodiesel provides evidence that these catalysts continue to evolve as viable alternatives. While liquid alkaline metal alkoxides remain to be appealing in the industries, it is expected that solid base catalyst will soon become more attractive due to the economics and environmental concern. Limited researches have shown that the conversion by solid base catalysts was comparable to that of the existing alkoxide system. This paper reviews various types of heterogeneous solid acids and bases in the production of biodiesel from transesterification of triglycerides. Unconventional enzymatic and non-catalytic supercritical methanol transesterification are also presented. The yields and conversion from various catalytic systems are compared, and the advantages and disadvantages of the systems discussed.

Manganese oxides at different oxidation states for heterogeneous activation of peroxymonosulfate for phenol degradation in aqueous solutions

Abstract: A series of manganese oxides (MnO, MnO2, Mn2O3 and Mn3O4) were synthesized and tested in heterogeneous activation of peroxymonosulfate (PMS) for phenol degradation in aqueous solutions. Their properties were characterized by several techniques such as X-ray diffraction (XRD), thermogravimetric-differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), and N2 adsorption/desorption isotherms. Catalytic activities of Mn oxides were found to be closely related to the chemical states of Mn. Mn2O3 is highly effective in heterogeneous activation of PMS to produce sulfate radicals for phenol degradation compared with other catalysts (MnO, MnO2, and Mn3O4). The activity shows an order of Mn2O3 > MnO > Mn3O4 > MnO2. Mn2O3 could completely remove phenol in 60 min at the conditions of 25 mg/L phenol, 0.4 g/L catalyst, 2 g/L PMS, and 25 °C. After heat regeneration, the activity could be fully recovered. A pseudo first order model would fit to phenol degradation kinetics and activation energy was obtained as 11.4 kJ/mol.

Young consumers insights on brand equity: effects of brand association, brand loyalty, brand awareness, and brand image

Abstract: Purpose – The purpose of this paper is to examine the effects of brand association, brand loyalty, brand awareness, and brand image on brand equity among young consumers. Design/methodology/approach – Data from 200 young consumers were analysed using descriptive, correlation and multiple regression analysis via the Statistical Package for Social Sciences computer programme version 21. Findings – Empirical results via multiple regressions authenticated that brand awareness predominantly affects brand equity among young consumers. These young consumers get input and awareness of the particular product or brand from the social media. They can clearly recognize the particular product or brand in comparison to competing products or brands and know how it looks and its characteristics from the social media. Research limitations/implications – Respondents were randomly drawn from the population of the full time students in a public university in Malaysia. Consequently, they may not represent the entire populatio...