A review on lignocellulosic biomass waste into biochar-derived catalyst: Current conversion techniques, sustainable applications and challenges
Graphical abstract
Introduction
With the increasing energy demands due to the rapid evolution of the world, the conventional raw materials, fossil fuels, no longer fulfil the energy demand as they are non-renewable and also bring negative impact to the environment [1]. The burning of fossil fuels causes climate change due to greenhouse gas emission, which brings negative impact to the ecosystem [2]. Thus, the concern on sustainable energy is necessary for a better environment and brings benefits to the economy and society. Lignocellulosic biomass is a common source of sustainable energy which is abundant in nature. It is an organic matter with carbohydrates building blocks derived from photosynthesis [3]. Biopolymers including 35–50% of cellulose, 20–35% of hemicellulose, and 10–25% of lignin are the three building structures of lignocellulosic biomass, which are shown in Fig. 1 [4,5]. Cellulose is a polymer composed of glucose which makes up the largest component of lignocellulosic biomass. Hemicellulose is a group of polysaccharides while lignin is a water-insoluble polymer that provides structural rigidity to plants [4,6]. Besides these three components, a small portion of non-structural components, ash exists in lignocellulosic biomass [7].
Lignocellulosic biomass is widely available in nature. It can be obtained in huge quantities at low cost. Hence, lignocellulosic feedstock material shows a prospective to replace non-renewable energy. Lignocellulosic biomass can be categorized into four groups, which are hardwood, softwood, grasses, and agricultural wastes [7,8]. According to Perea-Moreno et al. [9], research is conducted to analyze the number of scientific publications on biomass renewable energy topics. Since 2001 and up to 2018, the top 5 countries with the most publications are United States [[10], [11], [12], [13]], China [[14], [15], [16], [17], [18], [19]], India [[20], [21], [22]], Germany [[23], [24], [25], [26]], and Italy [9,[27], [28], [29], [30], [31]]. Apart from this, Canada [[32], [33], [34], [35]], Brazil [[36], [37], [38], [39]], Australia [[40], [41], [42]], Japan [[43], [44], [45], [46], [47]], Malaysia [[48], [49], [50], [51], [52]], Turkey [51,[53], [54], [55]], France [[56], [57], [58]], Spain [[59], [60], [61], [62], [63]], and Poland [[64], [65], [66], [67], [68], [69]] are also giving attention to biomass energy research [9]. Table 1 indicates the major biomasses available in these countries.
Lignocellulosic biomass is a potential feedstock to be transformed into valuable fuels and chemicals including bio-oil [70], biochar [71], syngas [72], and biogas [72] through biochemical or thermo-chemical conversion [7,73]. The biomass conversion techniques include gasification, pyrolysis, torrefaction, hydrothermal liquefaction, and hydrothermal carbonization as represented in Fig. 2 [74,75]. On the other hand, the biomass conversion efficiency can be increased by the pre-treatment of lignocellulosic biomass. Current pre-treatment technologies for lignocellulosic biomass include biological pre-treatments, physical pre-treatments, acid or alkaline pre-treatments, and thermal pre-treatments [76,77]. Pristine biochar is a solid carbon residual which is in black from the process of thermal decomposition of lignocellulosic biomass [73,78]. Modified biochar with advantageous surface area, porosity, and surface functional groups can be applied in various applications [79].
Researches on investigating the catalytic activity of biochar-derived material in processes including syngas cleaning and conversion, biofuel production, and pollution control are gaining increase attentions [79]. Furthermore, biochar-based material can be utilized to enhance the retention time of fertilizer in the soil, to increase the electrical conductivity in semiconductor, and as an adsorbent in removing heavy metals and organic substance from aqueous solution [80]. Carbon material can be applied directly in heterogeneous catalytic reaction as active component or acted as catalyst support [81]. Biochar-derived catalyst has gained increasing attention as it is a carbon-rich material that has the potential to replace conventional heterogeneous carbon-based catalysts [82]. For example, biochar contains inorganics components like Fe and K, which enhance the catalytic activity in tar removal [82].
To the best of our knowledge, there is still lack of comprehensive research on the transformation of lignocellulosic biomass into biochar-derived catalyst, by revealing the influences of various biomass conversion and biochar modification techniques on the physicochemical properties of the resulted catalyst, particularly in bioenergy production and air pollutant reduction. To date, the relationship of Industrial Revolution (IR) 4.0 with biomass industry and field of catalysis has scarcely been reported thoroughly. Therefore, the current review provides an in-sight analysis by comparing various biomass conversion techniques, in the aspects of process conditions, benefits, drawbacks, limitations, as well as the effect of various biomass conversion techniques and biochar modification techniques on the physical properties of pristine biochar and modified biochar. In addition, the characterization techniques used to determine the physicochemical properties of modified biochar are discussed thoroughly. In the application of biochar-derived catalyst, the catalytic performance and the unit production cost of biochar-derived catalyst are compared with conventional catalyst. Meanwhile, the impact of IR 4.0 on biomass industry is also highlighted in the present review. In short, the aim of present review is to provide comprehensive data, in-depth comparison and thorough discussion among various biomass conversion techniques and biochar modification techniques, as well as the influence on the properties of biochar-derived catalyst which is the key parameter in catalysis. Based on the understanding on properties of biochar-derived catalyst, the applications of the biochar-derived catalyst in biofuel production and NOx reduction are reviewed quantitatively and qualitatively.
Section snippets
Biomass conversion techniques
In this section, several biomass conversion techniques, including gasification, pyrolysis, torrefaction, hydrothermal liquefaction, and hydrothermal carbonization for biochar production, are discussed and compared in terms of operating conditions, type of products generated, production cost, as well as benefits, drawbacks and limitations.
Biochar modification techniques
Generally, pristine biochar that converted from lignocellulosic biomass exhibited limitations on surface area, pore volume, and surface functional groups that could eventually influence the role as a catalyst [159]. However, the properties of the biochar can be intensified and modified through chemical and physical activation approaches [160]. This section gives an outline of the effects of various modification techniques on the biochar surface area and pore volume.
Applications of biochar-derived catalyst
Modified biochar-derived catalysts with enhanced physicochemical properties are potentially serve as substitution to conventional catalyst in several applications, including biofuel production and NOx reduction. This section gives an outline of the catalytic performance of the biochar-derived catalyst in different applications. In addition, the catalytic performance is compared with the conventional catalyst.
Impacts of industrial revolution 4.0 on biomass industry
The fourth industrial revolution (IR 4.0) was originated in Germany and spread rapidly all over the world [239]. IR 4.0 focuses on sustainable production through smart factories, or to say towards a digitalization world by applying big data analytics and business intelligence, internet of things (IoT), cloud computing, cyber-security, autonomous robots, additive manufacturing, and augmented reality [239,240]. Additive manufacturing, which is also called 3D printing, can provide highly
Conclusions and prospects
Converting lignocellulosic biomass into biochar-derived catalyst is of great interest among researchers in the view of increasing demand for energy, environmentally friendly, economic benefits, and sustainable energy. This review paper provides an outline of the recent conversion techniques of lignocellulosic biomass, methods of modification of biochar, and the applications of the biochar-derived catalyst in biofuel production and pollution control. The conversion techniques and the effect of
Acknowledgements
This work was funded by Xiamen University Malaysia Research Fund (Grant no. XMUMRF/2020-C5/IENG/0028).
References (246)
- et al.
Lignocellulosic biomass pyrolysis mechanism: a state-of-the-art review
Prog. Energy Combust. Sci.
(2017) - et al.
Emerging technologies for the pretreatment of lignocellulosic biomass
Bioresour. Technol.
(2018) - et al.
Potential emission reductions by converting agricultural residue biomass to synthetic fuels for vehicles and domestic cooking in China
Particuology
(2020) - et al.
Economic analysis of converting of waste agricultural biomass into liquid fuel: a case study on a biofuel plant in China
Renew. Sustain. Energy Rev.
(2017) - et al.
Environmental evaluation of a distributed-centralized biomass pyrolysis system: a case study in Shandong, China
Sci. Total Environ.
(2020) - et al.
Pyrolysis of Chinese chestnut shells: effects of temperature and Fe presence on product composition
Bioresour. Technol.
(2019) - et al.
Biomass resources and potential of anaerobic digestion in Indian scenario
Renew. Sustain. Energy Rev.
(2017) - et al.
Small scale biomass gasification plants for electricity generation in India: resources, installation, technical aspects, sustainability criteria & policy
Renewable Energy Focus
(2019) - et al.
Biomass composition and ash melting behaviour of selected miscanthus genotypes in Southern Germany
Fuel
(2016) - et al.
A review of biomass potential and current utilisation – status quo for 93 biogenic wastes and residues in Germany
Biomass Bioenergy
(2016)
Small-scale biomass gasification CHP systems: comparative performance assessment and monitoring experiences in South Tyrol (Italy)
Energy
The potential of agricultural residues for energy production in Calabria (Southern Italy)
Renew. Sustain. Energy Rev.
Life cycle assessment of forest-based biomass for bioenergy: a case study in British Columbia, Canada, Resources
Conserv. Recycl.
Bioenergy production on marginal land in Canada: potential, economic feasibility, and greenhouse gas emissions impacts
Appl. Energy
Biomass torrefaction for energy purposes – definitions and an overview of challenges and opportunities in Brazil
Renew. Sustain. Energy Rev.
Review of the energy potential of the residual biomass for the distributed generation in Brazil
Renew. Sustain. Energy Rev.
Advances in thermochemical conversion of woody biomass to energy, fuels and chemicals
Biotechnol. Adv.
Transformation of durian biomass into a highly valuable end commodity: trends and opportunities
Biomass Bioenergy
An overview of biomass thermochemical conversion technologies in Malaysia
Sci. Total Environ.
Biomass and bioenergy: an overview of the development potential in Turkey and Malaysia
Renew. Sustain. Energy Rev.
Prospective for power generation of solid fuel from hydrothermal treatment of biomass and waste in Malaysia
Energy Procedia
Biomass energy potential and utilization in Turkey
Renew. Energy
Biogas energy opportunity of Ardahan city of Turkey
Energy
An integrated Multi-Regional Input-Output (MRIO) Analysis of miscanthus biomass production in France: socio-economic and climate change consequences
Biomass Bioenergy
Pyrolysis-GC–MS to assess the fungal pretreatment efficiency for wheat straw anaerobic digestion
J. Anal. Appl. Pyrol.
Assessment of forest bioenergy potential in a coal-producing area in Asturias (Spain) and recommendations for setting up a Biomass Logistic Centre (BLC)
Appl. Energy
Productivity and biomass characteristics of selected poplar (Populus spp.) cultivars under the climatic conditions of northern Poland
Biomass Bioenergy
Recent progress on catalytic pyrolysis of lignocellulosic biomass to high-grade bio-oil and bio-chemicals
Renew. Sustain. Energy Rev.
Advances in production and application of biochar from lignocellulosic feedstocks for remediation of environmental pollutants
Bioresour. Technol.
Evaluation of biogas and syngas as energy vectors for heat and power generation using lignocellulosic biomass as raw material
Electron. J. Biotechnol.
Hydrothermal carbonization of lignocellulosic biomass
Bioresour. Technol.
Pretreatment technologies for an efficient bioethanol production process based on enzymatic hydrolysis: a review
Bioresour. Technol.
Pretreatment of microalgae to improve biogas production: a review
Bioresour. Technol.
A review of biochar-based catalysts for chemical synthesis, biofuel production, and pollution control
Bioresour. Technol.
The role of carbon materials in heterogeneous catalysis
Carbon
Biochar as a catalyst
Renew. Sustain. Energy Rev.
Effects of gasifying agent on the evolution of char structure during the gasification of Victorian brown coal
Fuel
Gasification of non-woody biomass: a literature review
Renew. Sustain. Energy Rev.
Fire, explosion and chemical toxicity hazards of gasification energy from waste
J. Loss Prev. Process. Ind.
Insights into biochar and hydrochar production and applications: a review
Energy
Preparation, modification and development of Ni-based catalysts for catalytic reforming of tar produced from biomass gasification
Renew. Sustain. Energy Rev.
Sustainable gasification–biochar systems? A case-study of rice-husk gasification in Cambodia, Part I: context, chemical properties, environmental and health and safety issues
Energy Pol.
Review and analysis of biomass gasification models
Renew. Sustain. Energy Rev.
Energy production from biomass (part 3): gasification technologies
Bioresour. Technol.
Biomass-gasification-based atmospheric water harvesting in India
Energy
Effect of process parameters on production of biochar from biomass waste through pyrolysis: a review
Renew. Sustain. Energy Rev.
Current technologies for analysis of biomass thermochemical processing: a review
Anal. Chim. Acta
Fast pyrolysis of durian (Durio zibethinus L) shell in a drop-type fixed bed reactor: pyrolysis behavior and product analyses
Bioresour. Technol.
Scarcity-weighted fossil fuel footprint of China at the provincial level
Appl. Energy
Prevented mortality and greenhouse gas emissions from historical and projected nuclear power
Environ. Sci. Technol.
Cited by (33)
Prediction of biochar yield based on machine learning model of “enhanced data” training
2024, Biomass and BioenergyNovel strategy to produce polyaromatic compounds at low temperature for the production of secondary chars
2023, Journal of Analytical and Applied Pyrolysis