Production of bioethanol as useful biofuel through the bioconversion of water hyacinth (Eichhornia crassipes)

Abstract

Water hyacinth (Eichhornia crassipes) represents a promising candidate for fuel ethanol production in tropical countries because of their high availability and high biomass yield. Bioconversion of such biomass to bioethanol could be wisely managed through proper technological approach. In this work, pretreatment of water hyacinth (10 %, w/v) with dilute sulfuric acid (2 %, v/v) at high temperature and pressure was integrated in the simulation and economic assessment of the process for further enzymatic saccharification was studied. The maximum sugar yield (425.6 mg/g) through enzymatic saccharification was greatly influenced by the solid content (5 %), cellulase load (30 FPU), incubation time (24 h), temperature (50 °C), and pH (5.5) of the saccharifying medium. Central composite design optimized an ethanol production of 13.6 mg/ml though a mixed fermentation by Saccharomyces cerevisiae (MTCC 173) and Zymomonas mobilis (MTCC 2428). Thus the experiment imparts an economic value to water hyacinths that are cleared from choking waterways.

Water hyacinth second-generation ethanol production: a mitigation alternative for an environmental problem

“…Table 2 compare the found results in this work with the others two researches. Table 2 shows that the obtained yield, in this work, is better than Satyanagalakshmi et al (2011) results, however, is smaller than results found per Das et al (2016), that used two microorganisms for fermentation, S cerevisiae, a yeast normally utilized in alcohol fermentation, and Z. mobilis, one bacteria with more fast fermentation and that show the ethanol yield biggest than with yeast (Ernandes and Garcia-Cruz 2009).…”

“…When the process time decreases its productivity increases. Satyanagalakshmi et al (2011) and Das et al (2016) used Eichhornia crassipes as raw material by 2G ethanol production; however, both did the biomass pretreatment with sulfuric acid and did not study the SHF process. Table 2 compare the found results in this work with the others two researches.…”

“…Ethanol/natural water hyacinth: 0.0013 mL/g → 1.3 L/t. In 1 hectare grows 220 kg of water hyacinth per day, therefore in 1 year there are 80 ton of E. crassipes (Bayrakci and Koçar 2014;Das et al 2016). Although these figures can varies depending climate, water conditions, etc., with this rate is possible to produce in 1 year, 100 L of ethanol per each hectare of water hyacinth in hydric bodies.…”

Biohydrogen production by locally isolated facultative bacterial species using the biomass of Eichhornia crassipes: effect of acid and alkali treatment

“…The control measures adopted worldwide have exhibited varying extent of success, but complete eradication has not yet achieved (Ray et al 2009;Patel 2012;Stubbs and Kennedy 2012). However, studies have reported that water hyacinth can be a good source of energy owing to the profuse growth and abundance (Mathur and Singh 2004;Gunnarsson and Petersen 2007;Mishima et al 2008;Chuang et al 2011;Das et al 2016). The dry plant biomass mainly comprises of cellulose (18-31%), hemicellulose (18-43%) and lignin (7-26%) Bergier et al 2012;Barua and Kalamdhad 2016).…”

“…The high content of carbohydrate can be hydrolysed through acidic and alkaline treatment into fermentable sugars Aswathy et al 2009;Barua and Kalamdhad 2016). Efforts done to tap the biomass as a suitable feedstock for the production of biofuels like biogas (Vivekanand et al 2013;Barua and Kalamdhad 2016), bioethanol (Das et al 2016;Shanab et al 2017), biohydrogen Chuang et al 2011;Lazaro et al 2014) and biodiesel (Shanab et al 2017) have been proved successful O'Sullivan et al 2010;Sharma et al 2016).…”