Microwave Assisted Alkaline Pretreatment and Microwave Assisted Enzymatic Hydrolysis of Palm Oil Mill Effluent (POME) for Optimum Fermentable Sugar Yield

Abstract

Abstract:In the present study, a comparison of microwave assisted alkali pretreatment was tried using oil palm empty fruit bunch. The microwave assisted alkali pretreatment of POME using NaOH, significantly improved the enzymatic saccharification of POME by removing more lignin and hemicellulose and increasing its accessibility to hydrolytic enzymes. Enzymatic hydrolysis of POME suspension by various amylolytic enzymes was investigated to reveal the potential coupling mechanism of Microwave Irradiation-Enzyme Coupling Catalysis (MIECC). It was shown that enzymatic hydrolysis of POME using typical enzymes may successfully was carried out at microwave condition. The MIECC resulted in increasing initial reaction rate by about 3 times. The results testify on specific activation of enzymes by microwaves and prove the existence of nonthermal effect in microwave assisted reactions. Low power microwave irradiation (100W) does not increase the temperature beyond 40 o C and hence denaturation of the enzyme is avoided. The present study has highlighted the importance of well controlled microwave assisted enzymatic reaction to enhance the overall reaction rate of the process.

Recent advances on palm oil mill effluent (POME) pretreatment and anaerobic reactor for sustainable biogas production

“…One way to overcome this limitation is to use locally produced enzymes [74]. According to Nomanbhay and Hussain [75], POME is composed of soluble and insoluble carbohydrates. Soluble carbohydrates have a low concentration (0.0039 kg/L), while insoluble carbohydrates have a concentration of 0.026 kg/L in POME.…”

“…Using microwave irradiation during pretreatment could also accelerate enzymatic reactions. It has been reported that the enzymatic hydrolysis of POME produced only 0.0238 kg/L of reducing sugar, while microwave-irradiationassisted enzymatic hydrolysis yielded a higher amount of sugar reduction (0.0383 kg/L) [75]. Although the use of lab-scale microwave irradiation pretreatment has significantly improved biogas production, its industrial-scale use is unlikely due to its high cost.…”

Microwave Assisted Hydrolysis of Cellulose to Release Sugars from Pongamia Oil Cake for its use in Bioethanol Production

“…At 140 W, the temperature of reaction mixture (40-60 o C) was much lower in comparison with temperature at 420 W (80-100 o C). The thermal effect caused the variation in rate of reaction by altering the rate constants of the reaction 13,14 . Thus, it was expected that as the microwave power increased from 140 W to 420 W, reducing sugar concentration would also increase with time.…”

“…The dielectric properties of the reaction components determine the performance of a microwave process. Microwave has been successfully used for biomass pretreatment process [11][12][13] . Microwave irradiation accelerates the reaction due to the thermal and non-thermal effects 10,14 .…”