Integrated Multiproduct Biorefinery for Furfural Production with Acetic Acid and Lignin Recovery: Design, Scale-Up Evaluation, and Technoeconomic Analysis

Abstract

Furfural is a versatile platform and multipurpose chemical that can be produced with no carbon efficiency loss from pentose sugars present in prehydrolysate streams. Existing processes for the production of furfural are typically energy-intensive with limitations to recover value-added molecules and byproducts such as lignin and acetic acid. In this work, we demonstrate a novel integrated biorefinery process for furfural production with significant sustainability improvements to current production pathways. Higher conversion efficiency for C5 sugars into furfural is achieved with a novel reactor for producing and recovering furfural in the vapor phase that has been validated at the laboratory scale. Low molecular weight and sulfur-free lignin is also recovered while minimizing energy consumption by employing membrane filtration. Synergy was observed when lignin recovery is performed prior to furfural production. On the basis of experimental results, the scalability of the process for valorizing 3200 metric tonne/day of prehydrolysate solutions that is typically combusted in kraft dissolving pulp mills was evaluated. For a furfural production capacity of 36 tonne/day, a process configuration that stands out among four proposed alternatives was identified and designed. Significant heat energy savings (99.5%) for driving the process was achieved through a heat exchanger network design for internal heat recovery, which resulted in an energy intensity of 0.47 GJ/tonne, corresponding to 1% of the energy intensity for conventional processes. The technoeconomic assessment confirmed that even the least performing process is profitable, robust, and capital-efficient as indicated by metrics such as the internal rate of return (IRR) ranging from 30% to 46%, resistance to market uncertainty (RTMU) between 0.9 and 4.3 $/$, as well as return on capital employed (ROCE) between 49% and 91%.

Production of levulinic acid and alkyl levulinates: a process insight

“…As well as being a possible immediate source of energy recovery, lignin represents an origin of a large amount of bio-based chemicals, rich source of hydroxylic and carboxylic functional groups, potentially employable as substituents in polyurethane foam formulation, as adsorbents, precursors of catalysts, soil additives and energy store materials. 345,346 Due to the heterogeneous structure, its recovery can be a critical industrial challenge but several integrated biorefineries 347 have been designed, including it and significantly improving the overall process economy. 203 Depending on the primary target product asset, the lignin recovery could be designed as an upstream step, potentially advantageous thanks to the availability of organic solvent from pretreatments and efficient in the lignin fraction, or as a downstream step in the process.…”

“…203 Depending on the primary target product asset, the lignin recovery could be designed as an upstream step, potentially advantageous thanks to the availability of organic solvent from pretreatments and efficient in the lignin fraction, or as a downstream step in the process. 203,347 Besides solvent-based fractioning, membranes could also be effectively used in lignin recovery. 347 From the perspective of integrated processes, humins are also a potentially valuable "waste" product.…”

“…203,347 Besides solvent-based fractioning, membranes could also be effectively used in lignin recovery. 347 From the perspective of integrated processes, humins are also a potentially valuable "waste" product.…”

Ambient-pressure lignin valorization to high-performance polymers by intensified reductive catalytic deconstruction

“…Presently, lignin is separated from biomass at a rate of approximately 70 to 100 million metric tons/year through pulping or biorefining processes (11,12), but most isolated lignins have a dark color, strong odor, broad molecular weight distribution, and limited reactivity (5,(13)(14)(15), which restricts them to low-value applications (e.g., fillers for tires, asphalt, or concrete) (16,17). Furthermore, there is substantial variability in the composition, chemical structure, cost, and environmental impact of technical lignins due to differences among feedstocks and pulping/refining techniques (13,(18)(19)(20).…”

In‐depth material characterization of polyhydroxybutyrate from a forest biorefinery

“…6 Among lignocellulosic feedstock, integrated forest biorefineries are particularly promising in forest-rich countries such as Canada, Sweden, and Finland. 7 The main advantage is an existing collection of infrastructure and sustainable growth certification (e.g. by the Forest Stewardship Council), which allows constant feedstock supply at industrial scale.…”