Mini Review of Biodiesel by Integrated Membrane Separation Technologies That Enhanced Esterification/Transesterification

Abstract

Nowadays, the production of biodiesel from various renewable sources is becoming increasingly urgent because fossil fuels are becoming less and less available and accessible. Biodegradability, non-toxicity, and low pollution emissions are merely some properties making biodiesel a more environmentally friendly fuel. Esterification/transesterification is the most commonly used method to produce the biodiesel, whose reaction products are water/glycerol and mixed fatty acid esters. The membrane separation methods are applied to remove water/glycerol, which is capable of upsetting the chemical equilibrium of esterification/ transesterification controlled by thermodynamics and facilitating the reaction to proceed forward accordingly. The integrated membrane separation process is coupled with the chemical reaction, which could isolate a certain product from the reaction system with the reaction going on. That means that it is possible for the membrane separation technology to burst the restraints of original chemical equilibrium to gain the higher equilibrium conversion rate and yield. In comparison to other methods, the membrane separation technique coupled with chemical reaction has the ability to increase the reaction conversion rate, shorten the reaction time, and evenly reduce energy consumption.

Novel concepts for the biocatalytic synthesis of second-generation biodiesel

“…The resulting products (FAME and glycerol) and the catalyst dissolve in the methanol phase selectively permeates through the membrane into the permeate side, while unreacted oil retained due to its larger molecular size. The continuous permeation of biodiesel and glycerol, from the reactive system, promotes transesterification reaction in the direction of product formation and thus catalytic efficiency is enhanced (Ding et al, 2020). Membrane reactor technologies play a crucial role in enhancing industrial processes by selectively removing or transporting reactants and products, thereby improving reaction efficiency, selectivity, and overall performance (Basile, 2013).…”

Insight into the Recent Advances in Sustainable Biodiesel Production by Catalytic Conversion of Vegetable Oils: Current Trends, Challenges, and Prospects

“…Biofuel or FAME has similar physical and energetic characteristics to petroleum diesel fuel . The sustainability, availability, eco-friendly, and low environmental impact properties are considered as added values for biodiesel in the case of replacing petroleum diesel . This makes biodiesel the key player in the alternative energy revolution.…”

“…10 The sustainability, availability, eco-friendly, and low environmental impact properties are considered as added values for biodiesel in the case of replacing petroleum diesel. 11 This makes biodiesel the key player in the alternative energy revolution. The green energy revolution was established around the world to protect human health, seas, rivers, soils, and weather.…”

Membrane Performance on Biodiesel Production and Purification: A Review

“…However, conventional methods for biodiesel production present several drawbacks in processes, such as saponification, removal of catalyst, separation of glycerol, wastewater disposal, etc. After reaction, glycerin is separated from esters phase while purification of crude biodiesel is essential in order to meet the ultimate fuel specifications according to ASTM 6751 and EN 14214 standards [1,2]. Typical downstream purification methods involve wet and dry washing.…”

“…However, the application and sustainable performance of membrane technologies for biodiesel production on industrial scale is still challenging and under improvement [2]. In this study, recent experimental and modeling results were presented based on a systematic literature review.…”