Cellulose Emulsions and Their Hydrolysis

BACKGROUND The abundance and bio-renewability of cellulose renders it as a sustainable source for bio-fuels, yet its potential is not fully exploited. There is current interest in combined enzymatic processes in emulsified systems. Previous work described the formation of a stable non-crystalline cellulose coating on emulsified oil droplets. This raises significant questions regarding enzyme-substrate interactions in such systems. The aim of this work is to evaluate the ability of the enzyme to attack the cellulose shell on the surface of an oil droplet. This ability is foreseen to be relevant for advanced cellulose conversion processes, such as in the simultaneous extraction of reaction products and/or esterification. RESULTS Cellulose amphiphilicity was harnessed to fabricate oil-in-water emulsions using aqueous hydrogel dispersion fabricated from conventional alkaline solution. The cellulose shell on the surface of the oil droplets presents a huge non-crystalline surface. Altering the cellulose/oil ratio effects the emulsion dimensions and the rate of enzymatic hydrolysis, where the conversion of emulsions having lower oil content proved similar to that of regenerated cellulose gels (81 and 77% hydrolyzed cellulose after 4 h, respectively). CONCLUSION Cellulose-coated oil-in-water emulsion droplets are introduced as a novel substrate for cellulose hydrolysis for advanced conversion processes. (c) 2018 Society of Chemical Industry