Advances in nanocatalysts design for biofuels production

The exploitation of nanocatalysts, at the boundary between homogeneous and heterogeneous catalysis, is tracking new efficient ways to produce renewable biofuels in environmentally friendly conditions. Their solid state makes them recyclable, and their nanomateric particle size enables high activities approaching those offered by homogeneous catalysts, as well as novel and unique catalytic behaviors not accessible to solids above the nanometer range. Furthermore, the use of magnetically active materials has led to the development of nanocatalysts easily recoverable through the application of magnetic fields. In this mini-review, latest achievements in the production of advanced biofuels using stable, highly active, cheap and reusable nanocatalysts are described. Specifically, biodiesel and high density fuels have been chosen as major topics of research for the design of catalytic nanomaterials

Process design of continuous biodiesel production by reactive distillation:comparison between homogeneous and heterogeneous catalysts

Biodiesel production by reactive distillation processing is an attractive option to overcome the thermodynamic limitations inherently associated with conventional processes. Process simulations of transesterification of soybean oil and methanol were performed using the commercial package Aspen Plus (R). Four different continuous processes were designed and simulated by using homogeneous alkali-based catalysts and heterogeneous acid-based catalysts in both conventional reactor/distillation and reactive distillation. Effects of important operating and design parameters on performance of each process were analyzed and optimum conditions were determined. The proposed homogeneous alkali-catalyzed RD for biodiesel production did not only eliminate the requirement of separation and purification of the products but also improved the biodiesel yield at reduced methanol in the feed and at lower energy consumption in comparison with the conventional approach of sequential reaction and distillation. It was demonstrated that the heterogeneous magnesium methoxide, instead of homogeneous catalyst, offered significant benefits such as reaching less number of unit operations, reducing energy consumption, and not requiring neutralization, waste water disposal or salt waste processing. The energy requirement of the reactive distillation process catalyzed by magnesium methoxide was about 153 kWh/t biodiesel or 139.2 kWh/t biodiesel with an allocated purity of 98 wt% to glycerol by-produc

Simulation study of the biodiesel production from palm fatty acid distillate using palm empty fruit bunch catalyst in reactive distillation column

In this paper, the simulation study of biodiesel production from Palm Fatty Acid Distillate (PFAD) using Palm Empty Fruit Bunch (PEFB) catalyst as the heterogeneous acid catalyst in reactive distillation (RD) column was studied. The main parameters of the basic RD column such as the number of stages, molar ratio of feed, total number of stages, and reboiler heat duty were employed in the simulation study. The equilibrium stage and rate-based models were used for the RD simulation studies. The simulation studies show that the equilibrium stage model could describe the column profiles only qualitatively while the rate-based model was capable in describing the column profiles quantitatively and qualitatively. From simulation results, it can be concluded that the reactive distillation process with the Palm Empty Fruit Bunch catalyst offered advantages over the conventional process because it could eliminate the requirement of post-processing separation and purification at cost-effective column design and operating conditions. The optimum condition for producing biodiesel by reactive distillation using PEFB catalyst was found as follows: 4:1 of methanol to PFAD molar feed ratio, reflux ratio of 1.5, reboiler heat duty of 2.107 kJ/h and 3 reactive stages. This condition provided a FFA conversion of 97 wt% and biodiesel purity of 97.5%