@article{xu_rios_wang_ham_choi_kim_park_2024, title={Process design and techno-economic analysis for the lignin oil solvent recovery and purification process}, volume={434}, ISSN={["1879-1786"]}, DOI={10.1016/j.jclepro.2023.139999}, abstractNote={A technology to extract lignin oil from pretreated biomass has been developed for a cosmetic additive application (i.e., UV protection) through isopropyl alcohol without any catalyst. It was used for co-product lignin oil with XOS from a biorefinery process in this study. One of the key factors impacting economic feasibility is extraction solvent recovery, and it is important to design the process details based on techno-economic analysis. Therefore, this study has integrated lab experiments, process designs with Aspen Plus process simulations, and Excel-based techno-economic analysis to investigate the effect of solvent recovery on overall economics. Three options for solvent recovery (e.g., distillation, salting-out, and molecular sieve) have been explored. The salting-out method showed the best economic performance with an IRR of 33.6%, while the distillation method was 21.7% and the molecular sieve method was 16.7%. Key parameters are also identified by sensitivity analyses, which indicate the improvement potential for each case. This study has laid a foundation for lignin oil production studies, but its concept and approach can be applied to any solvent recycling in a biorefinery process, which is often neglected in lab-scale biorefinery studies.}, journal={JOURNAL OF CLEANER PRODUCTION}, author={Xu, Yiling and Rios, David Cruz and Wang, Song and Ham, Choonghyun and Choi, June-Ho and Kim, Hoyong and Park, Sunkyu}, year={2024}, month={Jan} }
 @article{kim_sriram_fang_kelley_park_2021, title={An eco-friendly approach for blending of fast-pyrolysis bio-oil in petroleum-derived fuel by controlling ash content of loblolly pine}, volume={179}, ISSN={["1879-0682"]}, DOI={10.1016/j.renene.2021.08.033}, abstractNote={This paper describes the effect of the ash content in biomass on the distribution of pyrolysis products and the miscibility of bio-oil in diesel. Ash content of loblolly pine wood (0.5 wt %, 1.1 wt %, and 1.5 wt %) was systematically varied by impregnating the wood with potassium carbonate solution. Variation in the ash content did not create a significant change in the chemical composition of the impregnated biomass. However, the response to a variety of thermal treatments changed significantly. The volatile matter content decreased from 88.3% to 78.2%, while the bio-oil yield declined from 45.7% to 29.9% as the ash content increased. Although the total organic yield decreased with increased biomass ash content, the total concentration of phenolic monomers increased from 2.8 mg/g to 20.2 mg/g, and bio-oil miscibility with a commercial diesel fuel increased from 6.7% to 13.4% based on wet bio-oil. The miscibility of guaiacol and 4-methyl guaiacol in diesel was higher than that of catechol, due to the lower polar and hydrogen bonding contribution. Test in a diesel engine showed a simultaneous reduction of HC and NOx emissions using diesel extracts.}, journal={RENEWABLE ENERGY}, author={Kim, Hoyong and Sriram, Subash and Fang, Tiegang and Kelley, Stephen and Park, Sunkyu}, year={2021}, month={Dec}, pages={2063–2070} }
 @article{lan_xu_kim_ham_kelley_park_2021, title={Techno-economic analysis of producing xylo-oligosaccharides and cellulose microfibers from lignocellulosic biomass}, volume={340}, ISSN={["1873-2976"]}, url={http://dx.doi.org/10.1016/j.biortech.2021.125726}, DOI={10.1016/j.biortech.2021.125726}, abstractNote={This study assesses the economic performance of a biorefinery producing xylo-oligosaccharides (XOS) from miscanthus by autohydrolysis and purification based on a rigorous model developed in ASPEN Plus. Varied biorefinery capacities (50–250 oven dry metric ton (ODMT)/day) and three XOS content levels (80%, 90%, 95%) are analyzed. The XOS minimum selling price (XOS MSP) is varied between $3,430–$7,500, $4,030–$8,970, and $4,840–$10,640 per metric ton (MT) for 80%, 90%, and 95% content, respectively. The results show that increasing biorefinery capacity can significantly reduce the XOS MSP and higher purity leads to higher XOS MSP due to less yield, and higher capital and operating costs. This study also explores another system configuration to produce high-value byproducts, cellulose microfiber, by utilizing the cellulose to produce microfiber instead of combusting for energy recovery. The XOS MSP of cellulose microfiber case is $2,460–$7,040/MT and thus exhibits potential economic benefits over the other cases.}, journal={BIORESOURCE TECHNOLOGY}, publisher={Elsevier BV}, author={Lan, Kai and Xu, Yiling and Kim, Hoyong and Ham, Choonghyun and Kelley, Stephen S. and Park, Sunkyu}, year={2021}, month={Nov} }
 @article{ou_dou_yu_kim_park_lee_kelley_park_2021, title={Techno-economic analysis of sugar production from lignocellulosic biomass with utilization of hemicellulose and lignin for high-value co-products}, volume={15}, ISSN={["1932-1031"]}, DOI={10.1002/bbb.2170}, abstractNote={Sugar derived from lignocellulosic biomass is an important intermediate product, often used for the production of biofuels and value‐added chemicals. It is therefore essential to understand and reduce the production costs of sugar derived from lignocellulosic biomass. This study evaluates the economic feasibility of a biorefinery producing sugar from lignocellulosic biomass using a combination of autohydrolysis and mechanical refining pretreatment. This biorefinery is self‐sufficient in energy, producing excess electricity for sale. The minimum sugar selling price (MSSP) that achieves a zero net present value is $446/metric ton. The possibility of using the two main by‐products, dissolved hemicellulose and lignin, for the production of high‐value products, xylitol and polyol, is also evaluated. When dissolved hemicellulose is used for xylitol production, the MSSP decreases to $347/metric ton. When lignin is liquefied to produce polyol, the MSSP is further reduced to $342/metric ton. External energy (natural gas) must be purchased if xylitol and polyol are produced. An analysis of capital and operating costs reveals that, although the production of xylitol and polyol incurs additional capital investment, their correspondingly high values outweigh the additional capital costs. Sensitivity analysis results indicate that efficient recovery and recycling of expensive chemicals like acetone and glycerol are key to the success of the biorefinery. Yields of xylitol and polyol also have strong impacts on the process economics. © 2020 Society of Industrial Chemistry and John Wiley & Sons Ltd}, number={2}, journal={BIOFUELS BIOPRODUCTS & BIOREFINING-BIOFPR}, author={Ou, Longwen and Dou, Chang and Yu, Ju-Hyun and Kim, Hoyong and Park, Yong-Cheol and Lee, Eun Yeol and Kelley, Stephen and Park, Sunkyu}, year={2021}, month={Mar}, pages={404–415} }
 @misc{narron_kim_chang_jameel_park_2016, title={Biomass pretreatments capable of enabling lignin valorization in a biorefinery process}, volume={38}, ISSN={["1879-0429"]}, DOI={10.1016/j.copbio.2015.12.018}, abstractNote={Recent techno-economic studies of proposed lignocellulosic biorefineries have concluded that creating value from lignin will assist realization of biomass utilization into valuable fuels, chemicals, and materials due to co-valorization and the new revenues beyond carbohydrates. The pretreatment step within a biorefinery process is essential for recovering carbohydrates, but different techniques and intensities have a variety of effects on lignin. Acidic and alkaline pretreatments have been shown to produce diverse lignins based on delignification chemistry. The valorization potential of pretreated lignin is affected by its chemical structure, which is known to degrade, including inter-lignin condensation under high-severity pretreatment. Co-valorization of lignin and carbohydrates will require dampening of pretreatment intensities to avoid such effects, in spite of tradeoffs in carbohydrate production.}, journal={CURRENT OPINION IN BIOTECHNOLOGY}, author={Narron, Robert H. and Kim, Hoyong and Chang, Hou-min and Jameel, Hasan and Park, Sunkyu}, year={2016}, month={Apr}, pages={39–46} }
 @article{jeong_jang_kim_yeo_choi_choi_2016, title={Effect of freeze storage on hemicellulose degradation and enzymatic hydrolysis by dilute-acid pretreatment of Mongolian oak}, volume={165}, journal={Fuel }, author={Jeong, H. S. and Jang, S. K. and Kim, H. Y. and Yeo, H. and Choi, J. W. and Choi, I. G.}, year={2016}, pages={145–151} }
 @article{kim_jang_hong_choi_choi_2016, title={Relationship between characteristics of ethanol organosolv lignin and the productivity of phenolic monomers by solvolysis}, volume={186}, journal={Fuel }, author={Kim, H. Y. and Jang, S. K. and Hong, C. Y. and Choi, J. W. and Choi, I. G.}, year={2016}, pages={770–778} }
 @article{jang_kim_jeong_kim_yeo_choi_2016, title={y Effect of ethanol organosolv pretreatment factors on enzymatic digestibility and ethanol organosolv lignin structure from Liriodendron tulipifera in specific combined severity factors}, volume={87}, journal={Renewable Energy}, author={Jang, S. K. and Kim, H. Y. and Jeong, H. S. and Kim, J. Y. and Yeo, H. and Choi, I. G.}, year={2016}, pages={599–606} }
 @article{kim_jeong_lee_choi_choi_2015, title={Pd-catalyst assisted organosolv pretreatment to isolate ethanol organosolv lignin retaining compatible characteristics for producing phenolic monomer}, volume={153}, journal={Fuel }, author={Kim, H. Y. and Jeong, H. S. and Lee, S. Y. and Choi, J. W. and Choi, I. G.}, year={2015}, pages={40–47} }