Kefeng Huang

Increasing the revenue from lignocellulosic biomass: Maximizing feedstock utilization

Replacing petroleum by biomass can be economically feasible by generating revenue from the three primary biomass constituents. The production of renewable chemicals and biofuels must be cost- and performance- competitive with petroleum-derived equivalents to be widely accepted by markets and society. We propose a biomass conversion strategy that maximizes the conversion of lignocellulosic biomass (up to 80% of the biomass to useful products) into high-value products that can be commercialized, providing the opportunity for successful translation to an economically viable commercial process. Our fractionation method preserves the value of all three primary components: (i) cellulose, which is converted into dissolving pulp for fibers and chemicals production; (ii) hemicellulose, which is converted into furfural (a building block chemical); and (iii) lignin, which is converted into carbon products (carbon foam, fibers, or battery anodes), together producing revenues of more than

Chemicals from Biomass: Combining Ring-Opening Tautomerization and Hydrogenation Reactions to Produce 1,5-Pentanediol from Furfural

500 per dry metric ton of biomass. Once de-risked, our technology can be extended to produce other renewable chemicals and biofuels.

Production of levoglucosenone and 5-hydroxymethylfurfural from cellulose in polar aprotic solvent–water mixtures

A process for the synthesis of 1,5-pentanediol (1,5-PD) with 84 % yield from furfural is developed, utilizing dehydration/hydration, ring-opening tautomerization, and hydrogenation reactions. Although this process has more reaction steps than the traditional direct hydrogenolysis of tetrahydrofurfuryl alcohol (THFA), techno-economic analyses demonstrate that this process is the economically preferred route for the synthesis of biorenewable 1,5-PD. 2-Hydroxytetrahydropyran (2-HY-THP) is the key reaction pathway intermediate that allows for a decrease in the minimum selling price of 1,5-PD. The reactivity of 2-HY-THP is 80 times greater than that of THFA over a bimetallic hydrogenolysis catalyst. This enhanced reactivity is a result of the ring-opening tautomerization to 5-hydoxyvaleraldehyde and subsequent hydrogenation to 1,5-PD.

Heat Exchanger Network Synthesis Using a Hyperstructure of Stagewise Stream Superstructures

We demonstrate a process to produce levoglucosenone (LGO) and 5-hydroxymethylfurfural (HMF) from cellulose in up to 65% carbon yield using sulfuric acid as catalyst and a solvent consisting of a mixture of tetrahydrofuran (THF) with water. In pure THF, LGO is the major product of cellulose dehydration, passing through levoglucosan as an intermediate. Increasing the water content (up to 5 wt%) results in HMF as the major product. HMF is formed both by glucose dehydration and direct dehydration of LGA. The maximum combined yield of LGO and HMF (∼65 carbon%) is achieved in the presence of 1–2.5 wt% H2O, such that comparable amounts of these two co-products are formed. THF gave the highest total yields of LGO and HMF among the solvents investigated in this study (i.e., THF, diglyme, tetraglyme, gamma-valerolactone (GVL), cyclopentyl methyl ether (CPME), 1,4-dioxane, and dimethyl sulfoxide (DMSO)). Furthermore, the rate of LGO and HMF degradation in THF was lower than in the other solvents. LGO/HMF yields increased with increased strength of the acid catalyst (H2SO4 > H3PO4 > HCOOH), and HMF was produced more selectively than LGO in the presence of hydrochloric acid. Techno-economic analysis for LGO and HMF production from cellulose shows that the lowest LGO/HMF production costs are less than

Heat exchanger network synthesis using a stagewise superstructure with non-isothermal mixing

3.00 per kg and occur at a cellulose loading and water content of 2–3% and 1.5–2.5% respectively.

Simultaneous synthesis approaches for cost-effective heat exchanger networks

Abstract The existing hyperstructure for the simultaneous heat exchanger network synthesis (HENS) have embedded the alternative structures excluded by a stagewise superstructure. However, the existing hyperstructure-based approaches employs pinch-based transshipment model and do not simultaneously allow cyclic matching. In this work, we propose a simultaneous mixed-integer nonlinear programming formulation based on a hyperstructure of multistage stream superstructures. We include cyclic matching, avoid the pinch-based transshipment model and allow exchangers for utilities in each stage. Using several examples, we demonstrate the significant advantages of our approach compared to those from the literature.