# Review on Fast Pyrolysis of Biomass for Biofuel Production from [PERSON]
## 1 Introduction  
Energy consumption has been growing in recent years due to population growth and economic development. By 2040, energy demand will increase by 37%, according to the International Energy Agency [1]. Renewable energy resources are composed of lignin, cellulose and hemicellulose and are becoming more popular because of the harmful effect of the use of fossil fuels on the environment. Biomass comprises organic material derived from plants. This material results from the use of sunlight to convert carbon dioxide and water into organic matter; this natural activity is named photosynthesis [2]. As biomass resources, we can cite wood waste, crops and their by-products, municipal solid waste, food processing waste, and aquatic plants and algae [2], as well as animal by-products and animal waste [3; 4; 5; 6]. Biomass technology is one of the best natural substituents for fossil resources, used for heating, generating electricity, and transport fuels production, chemicals, and biomaterials production [2]. It is also a considerable source of sustainable energy because it does not contribute to the accumulation of CO\({}_{2}\) in the atmosphere and, at the same time, helps in the recovery of degraded land and increases biodiversity [2]. Thanks to promising technological developments, biomass applications can be realized at a lower cost and with higher conversion efficiency, having a direct impact on jobs. The use of biomass for liquid fuel production involves thermochemical technologies, biological strategies, and multiple other strategies. One of the most common downstream biofuel production technologies is pyrolysis, followed by mild and deep hydrotreating [7]. Fast pyrolysis involves the thermal decomposition of biomass in an anaerobic environment; it is characterized by high temperature (above 450 \({}^{\circ}\)C) and short residence time, producing biofuel with a high yield of up to 75% on a dry biomass basis. Pyrolysis has been the subject of several works for the valorization of lignocellulosic biomass [8]. It consists of decomposing organic matter under the effect of heat in an inert atmosphere to produce gases, oils, and char. The three pyrolysis technologies, slow, fast, and flash, allow the process to be oriented towards the production of specific pyrolysis products depending on the processing conditions. Reactor technologies have been developed to produce pyrolysis oils, which have attracted increasing interest since the 1979 crisis. Indeed, these oils present an alternative to polluting fossil fuels. However, their application as fuel remains limited by their low calorific value (16-19 MJ/kg) due to their high water content (30%) and their richness in oxygenated compounds. Biomass-based economies extension is limited by problems associated with refining fast pyrolysis oils that are highly oxygenated oils. This challenge is preventing the large-scale use of these oils. Oxygen content is not the only problem that affects the performance of bio-oils during storage, handling, and upgrading, however; it also depends on the type and reactivity of these oxygen-carrying functional groups [7]. The main objective of this research work is the valorization of date palms for the production of biofuels. This study will highlight the different stages of the process. We start by studying the pretreatment process for fast pyrolysis and the preparation of the raw materials for biofuel production. We take into consideration in this review of the literature on fast pyrolysis the different synonyms used to describe the same phenomenon, in particular \"fast pyrolysis\", \"fast pyrolysis\", and \"flash pyrolysis\". From now on, we will use the term fast pyrolysis. This paper is organized as follows: Section 2 presents the research methodology; Section 3 provides an overview of biomass with different types; Section 4 deals with the fast pyrolysis of date palm biomass with synthesis and depicts a technology watch on the production of biofuel from date palms via fast pyrolysis technology; and Section 5 concludes the paper.