The utilization of biomass waste as a raw material for renewable energy is a global concern. Pyrolysis is one of the thermal treatments for biomass wastes that results in the production of liquid, solid and gaseous products. Unfortunately, the complex structure of the biomass materials matrix needs elevated heating to convert these materials into useful products. Microwave heating is a promising alternative to conventional heating approaches. Recently, it has been widely used in pyrolysis due to easy operation and its high heating rate. This review tries to identify the microwave-assisted pyrolysis treatment process fundamentals and discusses various key operating parameters which have an effect on product yield. It was found that several operating parameters govern this process such as microwave power and the degree of temperature, microwave absorber addition and its concentration, initial moisture content, initial sweep gas flow rate/residence time. Moreover, this study highlighted the most attractive products of the microwave pyrolysis process. These products include synthesis gas, bio-char, and bio-oil. The benefits and challenges of microwave heating are discussed.

https://www.mdpi.com/2227-9717/8/9/1190/pdf

Microwave-Assisted Pyrolysis of Biomass Waste: A Mini Review

Lignocellulosic biomass is a class of sustainable material that can be utilized as a raw feedstock in biofuel and chemical production. However, the complex matrix structure of lignocellulosic materials complicates conversion processes, such as enzymatic hydrolysis. Therefore, an efficient pretreatment process is required to disrupt the plant cell wall structure and maximize the recovery of valuable soluble components from lignocellulosic biomass during hydrolysis. In addition, an effective pretreatment method should use the minimum necessary amounts of energy and chemicals to minimize the cost of the end product. Further, it should reduce the formation of inhibitory compounds that affect enzymes and microorganisms during hydrolysis and fermentation, and it should be applicable to a wide variety of feedstocks. The research presented in this review has highlighted the pros and cons of the current technologies employed in pretreatment processes. Further study should be done to optimize and improve these technologies to enhance the efficiency of the production of biofuels and other valuable components.

Toward Sustainable Processes of Pretreatment Technologies of Lignocellulosic Biomass for Enzymatic Production of Biofuels and Chemicals: A Review

The present work utilized a by-product of the starch industry in Malaysia, Sago bark waste (SB), for pretreatment and enzymatic hydrolysis. SB was subjected to two types of alkaline pretreatment to...

Comparison of sodium hydroxide and sodium bicarbonate pretreatment methods for characteristic and enzymatic hydrolysis of sago palm bark

Aim of the study was to assess the suitability of the combined use of microwave radiation and sodium cumene sulfonate under optimized process conditions for the preparation of maize stillage biomass as a raw material for the production of cellulosic ethanol The key parameter guaranteeing a high level of lignin removal from biomass (ca 44%) was concentration of hydrotrope Even at high biomass concentration (16% w/v) and a cellulase enzyme dose of about 4 filter-paper units/g, maize stillage biomass subjected to microwave-assisted hydrotropic pretreatment was highly susceptible to enzymatic degradation, which resulted in 80% hydrolysis yield It is possible to obtain a fermentation medium with a very high glucose concentration (up to 80 g/L), without fermentation inhibitors and, as a consequence, to reach a very high level of sugar conversion to ethanol (concentration above 40 g/L), even as much as 95% of theoretical yield Microwave hydrotropic treatment with sodium cumene sulfonate is a very effective way to prepare waste maize stillage biomass for the production of cellulosic ethanol The degradation of the lignocellulose structure by the simultaneous use of microwaves and hydrotropes ensured a high degree of conversion of structural polysaccharides to bioethanol The method provides a high level of enzymatic degradation of cellulose, leading to a medium with high content of released sugars suitable for bioconversion, which is in line with assumptions of the second-generation ethanol production technology KEY POINTS: • Microwave-assisted hydrotropic pretreatment is a new way to cellulosic ethanol production • Microwave-assisted hydrotropic delignification removes 44% of lignin from biomass • No fermentation inhibitors are obtained after microwave-assisted hydrotropic pretreatment • High ethanol concentration (above 40 g/L) and fermentation yield (95% of theoretical yield) from biomass after microwave-assisted hydrotropic pretreatment

/pdf/microwave-assisted-hydrotropic-pretreatment-as-a-new-and-1omlamlatd.pdf

Microwave-assisted hydrotropic pretreatment as a new and highly efficient way to cellulosic ethanol production from maize distillery stillage

Aloe vera rind (AVR), a discarded solid biomass after extraction of gel finds no commercial importance could serve as a potent lignocellulosic feedstock for bioethanol production that prerequisite an efficient pretreatment to remove the lignin (16.4%, w/w). In the present study, the impact of mild acid pretreatment on AVR by using microwave energy with varied power (160 W, 320 W and 480 W) and its efficiency on saccharification was evaluated. Microwave acid pretreatment resulted in threefold decrease in recalcitrant lignin (5.58%, w/w) at 480 W than untreated AVR biomass. The effect of pretreatment on AVR biomass was characterized by various analytical techniques. X-Ray Diffraction (XRD) patterns deciphered an increase in cellulose crystallinity (14.8%) of delignified AVR biomass as compared to raw biomass (10.5%) and the extent of structural distortion after pretreatment was clearly indicated by Scanning Electron Microscopy (SEM). Fourier-Transform Infra-Red (FTIR) spectra revealed the disappearance of peak around 1241 cm−1 (C–O stretching) indicated the deacetylation of hemicellulose after pretreatment. Gas Chromatography Mass Spectrometry (GC–MS) analysis of liquid hydrolysate obtained after pretreatment unveiled the presence of higher fraction of carboxylic acids, esters, aromatic and aliphatic hydrocarbons as a result of lignin oxidation. The maximum reducing sugar obtained by crude cellulase from the delignified AVR biomass was found to be 296.8 ± 1.26 mg/g as compared to untreated AVR biomass (129.68 ± 2.34 mg/g). This study has shown the acid microwave pretreatment of AVR biomass could effectively improve the yield of fermentable sugars that are further used for ethanol production.

Delignification of Aloe Vera Rind by Mild Acid Associated Microwave Pretreatment to Persuade Enhanced Enzymatic Saccharification

Agriculture residues are a promising feedstock for value-added products from lignocellulosic waste. However, pretreatment of lignocellulosic materials is essential to facilitate enzymatic hydrolysis and improve sugar yield. The objective of this study is to evaluate the effect of acid or alkali during microwave-assisted pretreatment of dragon fruit foliage (DFF) that would make hydrolysis process more efficient. In the present study, distilled water and three chemicals were examined for their effects on releasing monomeric sugar during microwave treatment. Microwave-assisted pretreatment namely microwave-distilled water (M-H2O) (control); microwave-sulfuric acid (M-H2SO4); microwave-sodium hydroxide (M-NaOH); and microwave-sodium bicarbonate (M-NaHCO3) pretreatment were performed using 5% (w/v) of DFF as substrate at 800 watt microwave power for 5 minutes exposure time. Highest yield of monomeric sugar was found at 15.56 mg/g using M-NaOH pretreatment at 0.1N NaOH. For M-H2SO4 pretreatment, 0.1N H2SO4 produced 8.2 mg/g of monomeric sugar. Application of M-NaHCO3 pretreatment using 0.05N NaHCO3 solution released 6.45 mg/g of monomeric sugar. While, soaking DFF in distilled water and subjecting to microwave irradiation released 6.6 mg/g of monomeric sugar. Treatments with the lowest concentration (0.01 N) of the three chemicals released only small quantities of total monomeric sugars and less than that with distilled water. The changes in the physical structure of DFF prior to and after the microwave-assisted pretreatment are also reported.

Effect of microwave-assisted acid or alkali pretreatment on sugar release from dragon fruit foliage

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Saleem Ethaib Mohammad

Author Tools

Chat about Author

Papers

Effect of microwave-assisted acid or alkali pretreatment on sugar release from dragon fruit foliage