Room temperature esterification of high-free fatty acid feedstock into biodiesel.

The esterification of a high-free fatty acid feedstock to biodiesel is often performed in high-temperature conditions using either homogeneous or heterogeneous acid catalysts. Thus, this study attempts to esterify oleic acid to biodiesel in room temperature conditions using sulphuric acid as a catalyst and a homogenizer device. The influences of process parameters including the molar ratio of oleic acid to methanol, catalyst concentration and rotational speed on biodiesel conversion were determined in different reaction times. The maximum conversion of 96.1 ± 0.4% was obtained in the presence of a molar ratio of 1 : 12, catalyst concentration of 0.7 mol L-1, a rotational speed of 4000 rpm and a reaction time of 30 minutes. The catalytic reusability test showed that the addition of fresh methanol is required to maintain the catalytic activity. However, the homogenizer-intensify esterification of oleic acid to biodiesel showed better performance than other methods as the reaction could conducted at room temperature and at a short reaction time. The predicted biodiesel properties meet the international standard except for oxidative stability. However, the flow properties revealed that the biodiesel can be used in winter season.

Waste rubber seeds as a renewable energy source: direct biodiesel production using a controlled crushing device.

A multistep and high-cost biodiesel production could be simplified using the direct transesterification (DT) method. A controllable device has been developed and applied to study the effects of the ratio of rubber seeds to methanol, catalyst concentration, reaction time and rotational speed on biodiesel conversion and fatty acid (FA) yield extraction. The controllable crushing device (CCD) assisted the DT of rubber seeds and operated at ambient temperature and pressure achieved a maximum biodiesel conversion of 97.5 ± 0.6% in a reaction time of 7 minutes. The biodiesel quality estimated based on the FA extraction profile is comparable with the biodiesel standard. In terms of energy efficiency and reaction time, the CCD saved 71-98% energy consumption and reduced the reaction time up to 99%.

Waste Passion Fruit Peel as a Heterogeneous Catalyst for Room-Temperature Biodiesel Production.

A low-cost, green, and highly active catalyst which could transesterify oil under ambient conditions is required to reduce the biodiesel production cost. A novel heterogeneous catalyst derived from the waste agroproduct has been developed from passion fruit peel. The catalytic activity of calcined waste passion fruit peel (WPFP) which mainly contains potassium in the form of chloride and carbonate has been evaluated using factorial design to determine the interaction of molar ratio of oil to methanol, catalyst weight, and reaction time with three different reaction conditions such as 65, 45 °C, and room temperature. The transesterification of palm oil to biodiesel achieved a conversion of >90% for all variables determined at a reaction temperature of 45 and 65 °C, respectively, while a maximum biodiesel conversion of 95.4 ± 2.8% was obtained at room temperature and a reaction time of 30 min. The addition of certain amounts of the catalyst is required to reuse the catalyst as the leaching study showed the reduction of 22% of catalyst weight. The ability of calcined WPFP to catalyze transesterification at room temperature opens up the possibility to reduce biodiesel production cost.

The loading effect of Pt clusters on Pt/graphene nano sheets catalysts.

In this paper, we report about chemically interaction between Pt Subnano-Clusters on Graphene Nano Sheets (GNS). The aim of this research is to clarify the size effect of Pt clusters on Pt 1-7 wt.%/GNS. This research is an experimental laboratory research. GNS was synthesized by using modified Hummer's method and 1-7 wt.% Pt/GNS were prepared with impregnation method. Then, they were analyzed with TG/DTA, XRD, TEM and XPS, respectively. The results show that Pt clusters are well deposited on GNS (TG/DTA and TEM data). Those data also are consistent with XRD data. The weak and broad peaks appear at 2θ = 39°, indicating Pt metal exists on GNS. The state of Pt is confirmed by using XPS. The appearance of Pt 4f. peaks proves that Pt metal is chemical interaction on GNS. The size of Pt clusters may affect the chemically properties of Pt/GNS catalysts.