Biodiesel production methanol recovery

In many cases, the conversion at the reactor is low and the unreacted species need to be recycled. Duran and Grossmann [19] proved that we can improve the conversion of the recycled systems by simultaneous optimization and heat integration if the conversion of the reaction is variable compared to sequential approaches. Recently, this concept was used in the design of biodiesel production processes where methanol or ethanol was used in excess in the transesterification reaction to move the equilibrium toward biodiesel, which needs to be recycled. The recovery of the alcohol determines the energy consumption of the process and thus the operating conditions at the reactor must be adjusted to reduce the energy needed in the recovery of the alcohol. The optimal operating conditions at the reactor differ from the ones reported where the reactor is evaluated alone [20,21]. 

Dhar, B.R., Kirtania, K., 2009. Excess methanol recovery in biodiesel production process using a distillation column a simulation study. Chemical Engineering Research Bullettin 13,55-60. 

Numerous types of basic heterogeneous catalysts, such as alkahne earth metal oxide, anion exchange resins and alkali metal compounds supported on alumina or zeolite can catalyze various chemical reactions such as isomerization, aldol, Michael, and Knoevenagel condensation, oxidation and transesterification [1], Today considerable attention is devoted to the production of biodiesel (FAMEs) as an alternative for petroleum-derived diesel fuel. Biodiesel is synthesized by direct transesterification of vegetable oil or animal fat with a short-chain alcohol, viz. methanol, ethanol, and isopropanol in presence of an acid, base or enzymatic catalyst [2], Considering the advantages of solid base catalysts, for easy separation and recovery, reduced corrosion and environmental acceptance [1], many studies have been conducted on basic heterogeneous catalysts development for biodiesel production [3-13],... 

The implementation of biorefineries will help to increase the economic viability of the biofuel industry. Disposing glycerol with methanol in it can pose harmful side effects to humans and the environment. Biorefineries will prevent the major issues pertaining to the disposal of biodiesel waste. The processing of oils and fats within the concept of a biorefinery and the chemical recovery and production of other valuable products is shown in Fig. 19.5. 

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