# Element-Based Predictive Modeling of Hydrothermal Liquefaction Bioproducts Derived from Corn Stover

## TL;DR

This paper introduces a new model to predict the outcomes of converting corn stover into biofuels using a process called hydrothermal liquefaction.

## Contribution

A novel element-based kinetic model is developed to predict product yields and characteristics from corn stover hydrothermal liquefaction.

## Key findings

- The model accurately predicted the elemental composition and fuel characteristics of solid residue and heavy bio-oil.
- Power function relationships were identified between corn stover amounts and product fractions under identical conditions.
- Predicted data matched observed trends on the van Krevelen diagram and H/C atomic ratios.

## Abstract

The hydrothermal liquefaction (HTL) process offers an
energetic
advantage over pyrolysis because it does not require prior drying
of the biomass feedstock. However, there are significant challenges
in simultaneously estimating both the yields and characteristics of
products from the HTL of biomass with theoretical support. This study
developed a unique element-based kinetic model to predict the yields,
higher heating values, and fuel characteristics of solid residue and
heavy bio-oil, based on the temperature, residence time, solid loading,
and elemental composition (C, H, N, and O) of corn stover. Furthermore,
the model predicted the weights of dissolved carbon and nitrogen in
the aqueous phase. HTL experiments were conducted using corn stover
at temperatures ranging from 250 to 350 °C for residence times
between 5 and 60 min. The resulting solid and liquid products were
analyzed for the elemental composition and ash content. The experimental
data and MATLAB program were used to predict the products. The fuel
characteristics derived from predicted elemental weight data of solid
residues followed the trend line of the observed data on the van Krevelen
diagram. In those of heavy bio-oil, the H/C atomic ratio of the average
predicted data matched the one calculated from the observed data.
Additionally, power function relationships between the amounts of
corn stover and obtained product fractions were identified under identical
temperature and residence time conditions by varying solid loading,
providing insights into the partial nonlinear behavior of the reaction
system.