Continuous System of Combined Columns of Ion Exchange Resins and Activated Charcoal as a New Approach for the Removal of Toxics from Sugar Cane Bagasse Hemicellulosic Hydrolysate

Abstract

A continuous system of combined columns of ion exchange resins and activated charcoal was proposed as a new approach for the removal of toxics from sugar cane bagasse hemicellulosic hydrolysate. A factorial design was carried out to evaluate the influence of temperature and feed flow rate in the performance of the detoxification procedure. By using a temperature of 30 °C and a flow rate of 2.5 VB/h, the total removal of furfural and 5-(hydroxymethyl) furfural was observed, as well as a large reduction in the color and concentration of phenolic compounds. Removal of metals was also observed, with 50, 63, and 23% reduction in the concentration of copper, chromium, and nickel, respectively. The product of the detoxification process was a hydrolysate with a reduced concentration of inhibitors that can be used as a raw material for a number of processes to obtain products of economic and social interest.

Short-term Adaptation Strategy Improved Xylitol Production by Candida guilliermondii on Sugarcane Bagasse Hemicellulosic Hydrolysate

“…Diluted acid hydrolysis is commonly used for this purpose due its low cost, easy operation, short reaction times, and effectiveness as it allows the recovery of 70 to 95% of the monomeric sugars [4]. However, in addition to sugars, this process results in the release/formation of toxic compounds to microorganisms, which reduce the yield and productivity of fermentation process [8][9][10][11].…”

“…Detoxi cation of hemicellulosic hydrolysates is often performed to reduce their toxicity to microorganisms, being the adsorption with activated carbon commonly used for this purpose [9,10,22].…”

“…However, this method has some disadvantages, such as the loss of sugars and waste generation, which are di cult to recycle and regenerate [10,23]. Alternative methodologies to detoxi cation methods, such as cell adaptation techniques, have been suggested to develop robust and tolerant strains and overcome the toxicity of hydrolysates [19,24].…”

Removal of furan and phenolic compounds from simulated biomass hydrolysates by batch adsorption and continuous fixed-bed column adsorption methods

“…These inhibitors include aliphatic carboxylic acids, furans, and phenolic compounds. The removal of such inhibitors has been reported using various separation methods including alkali treatment, vacuum evaporation, activated charcoal adsorption, ion exchange resin adsorption, nanofiltration, and their combinations (Bras et al, 2014;Geddes et al, 2015;Persson et al, 2002;Ra et al, 2015a,b;Santos et al, 2014;Soleimani et al, 2015;Zhang et al, 2015b). However, because these researchers' endeavors have been mostly concerned with completely removing inhibitors in an attempt to improve ethanol yield, the loss of sugar has not been thoroughly considered.…”

“…However, because these researchers' endeavors have been mostly concerned with completely removing inhibitors in an attempt to improve ethanol yield, the loss of sugar has not been thoroughly considered. Activated charcoal has been widely used as an adsorbent to remove inhibitors such as furans and phenolic compounds whose hydrophobicity is much greater than sugars and aliphatic carboxylic acids in lignocellulosic hydrolysates (Mussatto et al, 2004;Ra et al, 2015a,b;Rodrigues et al, 2001;Sahu et al, 2008;Santos et al, 2014;Soleimani et al, 2015;Sulaymon and Ahmed, 2008). This is because activated charcoal is able to adsorb these compounds due to its large adsorption capacity and strong hydrophobicity.…”