Intermediate batch pyrolysis of lignin for bio-products and energy Renato Nistri 1,* , Andrea Maria Rizzo 1 , David Chiaramonti 1 1. RE-CORD / Department of Industrial Engineering - University of Florence, via S. Marta 3, 50139 Firenze (IT) * : corresponding Author: renato.nistri@unifi.it; tel.: + 39 055 4796738; Mobile: +39 338 1123886 Abstract and Full Paper: Lignin is an aromatic polymer, consisting in randomly linked phenolics, found in lignocellulosic biomasses. Thanks to its structure, it is the main renewable source of aromatic chemicals and it is regarded by the scientific community as a promising feedstock to improve the economics of lignocellulosic biorefinery for the production of high added- value chemicals and energy. Lignin-rich residue from 2 nd -generation bioethanol process was analysed to settle a preliminary characterization of this compound and its properties compared toward conventional organic feedstocks. The sample was characterized in its chemical and physical properties (proximate and ultimate analysis, calorific value, etc) and thermogravimetric behavior. The latter was investigated through non-isothermal thermogravimetric analysis in nitrogen atmosphere under slow to moderate heating rate and final temperature up to approx. 800 °C. Solid residues produced at 300 °C and 800 °C from TGA were also analysed to determine the ultimate composition of chars. Several hundred grams of lignin residue were then processed in a newly designed batch pyrolysis pilot reactor, with throughput up to 1.5 kg h -1 of material, and pyrolysis liquid collected, analysed and compared with a sample of fast pyrolysis from pine chips. This preliminary investigation aimed at carrying out a first characterization of lignin pyrolysis products (solid, liquid and gaseous compounds) and highlighting any possible criticalities of the lignin feeding. Compared to oil from lignocellulosic feedstock, lignin pyrolysis oil exhibited peculiar behavior in TGA as well as different chemical and physical properties. These data can potentially be used in the design and modeling of thermochemical conversion processes of lignin. 1. Introduction: During the last years the problems related to environment sustainability and the increasing greenhouse emissions concern have led the scientific world to study and develop new clean technologies for energy production. Researchers have also focused their attention on biofuel production in a sustainable way and a very promising technology, that is becoming an industrial reality, is the production of second generation bioethanol that permits to exploit marginal lands overcoming the food vs fuel issue. The second generation bioethanol process produces a byproduct rich in lignin, a component of lignocellulosic biomass, that seems to be a very promising material for the economic sustainability of the whole process and it could be helpful in developing a biorefinery that integrates biomass conversion processes and equipment to produce fuels, power, and chemicals from biomass. The simplest and economic way to use lignin rich residues is the combustion, in order to provide heat and power to the process [1]. On the other hand the study of new technologies for better utilize the residue is needed, as the potential of the lignin is very attractive due to its chemical structure that suggests it may be a good source of valuable chemicals if it could be broken into smaller molecular units [2]. Indeed lignin is a biobased aromatic raw material that is abundantly available at relatively low costs. For this reason lignin appears as a versatile raw material for many applications and a deep research to understand if a competitive industry can be developed is needed. The residue properties strongly depend on the process used for biomass delignification and on the type of starting biomass, making