Effect of Pyrolysis Temperature on the Characterisation of Dissolved Organic Matter from Pyroligneous Acid

Abstract

Dissolved organic matter (DOM) greatly influences the transformation of nutrients and pollutants in the environment. To investigate the effects of pyrolysis temperatures on the composition and evolution of pyroligneous acid (PA)-derived DOM, DOM solutions extracted from a series of PA derived from eucalyptus at five pyrolysis temperature ranges (240–420 °C) were analysed with Fourier transform infrared spectroscopy, gas chromatography–mass spectroscopy, and fluorescence spectroscopy. Results showed that the dissolved organic carbon content sharply increased (p < 0.05) with an increase in pyrolysis temperature. Analysis of the dissolved organic matter composition showed that humic-acid-like substances (71.34–100%) dominated and other fluorescent components (i.e., fulvic-acid-like, soluble microbial by-products, and proteinlike substances) disappeared at high temperatures (>370 °C). The results of two-dimensional correlation spectroscopic analysis suggested that with increasing pyrolysis temperatures, the humic-acid-like substances became more sensitive than other fluorescent components. This study provides valuable information on the characteristic evolution of PA-derived DOM.

Sustainable Plant Growth Promotion and Chemical Composition of Pyroligneous Acid When Applied with Biochar as a Soil Amendment

“…Tyrosine and phenylalanine are aromatic amino acids, also considered to be biostimulant materials [ 35 ]. Humic-like substances have been previously identified in PA by other authors [ 5 ], and are often considered biostimulants for plant growth [ 36 ]. Humic-like substances may induce ATPase pumps in root tissues, thereby promoting root elongation through an auxin-like effect [ 36 ].…”

“…PA (also referred to as wood vinegar, pyroligneous liquor, pyroligneous extract, pyrolysis oil, or aqueous phase bio-oil) is a liquid material with condensed and highly oxygenated organic acids, arising from reactions between volatile elements generated during thermal decomposition. PA is composed of water (80–90%) and more than 200 organic compounds, including acids, alcohols, phenols, aldehydes, and esters (10–20%) depending on pyrolysis conditions [ 1 , 2 , 3 , 4 , 5 ]. Some of these compounds have antioxidant properties and can be developed into a range of useful products [ 6 , 7 , 8 , 9 , 10 ].…”

“…This work reports on the effect of combined applications of chemical fertilizer, biochar, and PA on plant growth in a pot experiment (treatments described in Table 1 ). To characterize chemical profiles of the organic inputs, four spectroscopic measurements of fluorescence excitation were utilized—excitation-emission matrix (EEM) [ 5 , 10 ], ion chromatography [ 26 ], high-performance liquid chromatography (HPLC) [ 20 ], and gas chromatography-mass spectrometry (GC-MS) [ 8 , 26 , 27 ]. The effect of inputs on growth of Komatsuna plants ( Brassica rapa var.…”

Exploration of the Interrelationship within Biomass Pyrolysis Liquid Composition Based on Multivariate Analysis

“…Pyrolysis liquid (PA), also named pyroligneous acid, is a crude condensate generated from the distillation of smoke produced during biomass pyrolysis, and is highly oxygenated organic smoke liquid, comprising organic acids, phenolics, aldehydes, ketones and alcohols [ 3 , 4 ]. PA can be used as antimicrobial and antioxidant agents to improve plant growth and enhance soil nutrient health conditions because of its advantageous physical and chemical properties [ 5 , 6 ].…”