Effects of Treatments on Cellulosic Biomass Structure in Ethanol Manufacturing: A Literature Review

2011 ◽  
Author(s):  
Qi Zhang ◽  
Pengfei Zhang ◽  
Z. J. Pei ◽  
Linda Pei
Keyword(s):  
Particle Size ◽  
Enzymatic Hydrolysis ◽  
Literature Review ◽  
Crystallinity Index ◽  
Degree Of Polymerization ◽  
Cellulosic Biomass ◽  
Experimental Investigations ◽  
Structure Parameters ◽  
Transportation Fuels ◽  
Biomass Structure

Ethanol made from cellulosic biomass is an alternative to petroleum-based liquid transportation fuels. Enzymatic hydrolysis uses enzymes to convert cellulosic biomass into sugars that are fermented into ethanol. In order to increase sugar yield, various treatments (such as biomass size reduction and pretreatment) are applied to cellulosic biomass before enzymatic hydrolysis. These treatments will alter structure parameters of cellulosic biomass, such as crystallinity index, degree of polymerization, particle size, pore volume, and specific surface area. There are currently no review papers on these structure parameters of cellulosic biomass in ethanol manufacturing. This paper reviews experimental investigations in the literature about effects of various treatments on the structure parameters of cellulosic biomass.

An Experimental Investigation on Cellulosic Biofuel Manufacturing: Effects of Biomass Particle Size on Sugar Yield

2011 ◽  
Author(s):  
Pengfei Zhang ◽  
Qi Zhang ◽  
Z. J. Pei ◽  
Linda Pei
Keyword(s):  
Experimental Investigation ◽  
Particle Size ◽  
Enzymatic Hydrolysis ◽  
Crystallinity Index ◽  
Cost Effective ◽  
Sugar Yield ◽  
Cellulosic Biomass ◽  
Experimental Investigations ◽  
Cellulosic Biofuel ◽  
Biomass Particle Size

Biofuels made from cellulosic biomass are an alternative to petroleum-based liquid transportation fuels. A key barrier to cost-effective manufacturing of cellulosic biofuel is low sugar yield in enzymatic hydrolysis. Particle size and crystallinity index of cellulosic biomass are two important parameters in enzymatic hydrolysis. The current literature contains many experimental investigations about effects of biomass particle size on sugar yield. However, particle size, often reduced by ball milling, is correlated with crystallinity index. Changes in particle size usually cause changes in crystallinity index. Therefore, particle size and crystallinity index may have confounding effects on sugar yield. Relations between particle size and sugar yield are not clear. This paper reports an experimental investigation on sugar yields from switchgrass particles produced by three methods: cutting milling, hammer milling, and manual cutting. The particles have different sizes but the same crystallinity index. Results show that there are no significant differences among sugar yields from these particles of different sizes. Particle size within the tested range has no significant effects on sugar yield.

Effects of Water Soaking on Biomass Particle Size in Cellulosic Biofuel Manufacturing

2012 ◽  
Author(s):  
Hera Wu ◽  
Pengfei Zhang ◽  
Qi Zhang ◽  
Z. J. Pei
Keyword(s):  
Particle Size ◽  
Sugar Yield ◽  
Cellulosic Biomass ◽  
Particle Sizes ◽  
Cellulosic Biofuels ◽  
Transportation Fuels ◽  
Cellulosic Biofuel ◽  
Before And After ◽  
Invasive Method ◽  
Biomass Particle Size

Cellulosic biofuels are an alternative to petroleum-based liquid transportation fuels. However, manufacturing costs of cellulosic biofuels are high partially due to low density and sugar yield of cellulosic biomass. Previous studies show that UV-A pelleting can increase the density and sugar yield of cellulosic biomass. A hypothesis for UV-A pelleting to increase the density and sugar yield of cellulosic biomass is that UV-A pelleting can reduce biomass particle size. To test this hypothesis, biomass particle sizes before and after UV-A pelleting need to be compared. Soaking pellets in water is an efficient and non-invasive method to separate pellets into particles. However, water soaking itself might change biomass particle size. This paper reports an investigation on effects of water soaking on biomass particle size. The biomass particle sizes before and after water soaking are measured and compared. Results show that effects of water soaking on biomass particle size are dependent on the initial particle size (particle size before water soaking) and time period of water soaking.

Ultrasonic Vibration-Assisted Pelleting of Sorghum Stalks: Effects of Pressure and Ultrasonic Power

2010 ◽  
Author(s):  
Qi Zhang ◽  
P. F. Zhang ◽  
Timothy Deines ◽  
Z. J. Pei ◽  
Donghai Wang ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Ultrasonic Vibration ◽  
Large Scale ◽  
Cost Effective ◽  
Sugar Yield ◽  
Cellulosic Biomass ◽  
Ultrasonic Power ◽  
Cellulosic Biofuels ◽  
Transportation Fuels ◽  
Low Efficiency

Cellulosic biofuels can be used to replace traditional liquid transportation fuels. Cellulosic biomass is feedstock in manufacturing of cellulosic biofuels. However, the low density of cellulosic biomass feedstock hinders large-scale and cost-effective manufacturing of cellulosic biofuels. Another bottleneck factor in manufacturing of cellulosic biofuels is the low efficiency of the enzymatic hydrolysis of cellulosic biomass materials resulting in a low sugar yield. Ultrasonic vibration-assisted (UV-A) pelleting can increase the density of cellulosic biomass feedstocks via combined effects of mechanical compression and ultrasonic vibration of the tool on the cellulosic biomass. Meanwhile ultrasonic vibration may act as a beneficial pretreatment for enzymatic hydrolysis, which can possibly increase the efficiency of hydrolysis and obtain a higher sugar yield. The pressure and the ultrasonic power are important parameters in UV-A pelleting. Their effects on pellet quality (density, durability, and stability) and sugar yield (after hydrolysis) are experimentally investigated.

Dilute Acid Pretreatment and Enzymatic Hydrolysis of Woody Biomass for Biofuel Manufacturing: Effects of Particle Size on Sugar Conversion

2013 ◽  
Author(s):  
Meng Zhang ◽  
Xiaoxu Song ◽  
Pengfei Zhang ◽  
Z. J. Pei
Keyword(s):  
Weight Loss ◽  
Particle Size ◽  
Enzymatic Hydrolysis ◽  
Sugar Yield ◽  
Total Sugar ◽  
Cellulosic Biomass ◽  
Dilute Acid Pretreatment ◽  
Promising Alternative ◽  
Biomass Particle Size ◽  
Sugar Conversion

Biofuels derived from cellulosic biomass offer a promising alternative to petroleum-based liquid transportation fuels. Cellulosic biomass can be converted into biofuels through biochemical pathway. This pathway consists of two major conversions: sugar conversion and ethanol conversion. Sugar yield in sugar conversion is critical to the cost effectiveness of biofuel manufacturing, because it is approximately proportional to the ethanol biofuel yield. Cellulosic biomass sugar conversion consists of pretreatment and enzymatic hydrolysis. Biomass particle size is an important factor affecting sugar yield. The literature contains many studies investigating the relationship between particle size and sugar yield. Many studies focused only on the sugar yield in enzymatic hydrolysis, and failed to take into account the biomass weight loss during pretreatment. This weight loss results in a loss of the amount of potential sugar (cellulose), which continues going into enzymatic hydrolysis. Without considering this loss, cellulosic biomass with a higher enzymatic hydrolysis sugar yield may end up with a lower total sugar yield through sugar conversion. The present study aims to address this issue by investigating the effects of biomass particle size using total sugar yield, a parameter considering both the biomass weight loss in pretreatment and the sugar yield in enzymatic hydrolysis.

Effects of Particle Size on Biomass Pretreatment for Biofuel Production

2019 ◽  
Author(s):  
Yang Yang ◽  
Mingman Sun ◽  
Timothy Deines ◽  
Meng Zhang ◽  
Jun Li ◽  
...  
Keyword(s):  
Particle Size ◽  
Enzymatic Hydrolysis ◽  
Dry Weight ◽  
Sugar Yield ◽  
Biofuel Production ◽  
Biomass Pretreatment ◽  
Current Status ◽  
Biomass Structure ◽  
Before And After ◽  
Biomass Particle Size

Abstract Biofuel production needs to be more efficient than its current status to increase its competitiveness. The multistep biofuel production is consisted of processes on biomass preprocessing and bioconversion stages. As a crucial parameter, biomass particle size has significant effects on both stages. It is essential to have an insightful understanding of the effects of particle size on sugar yield. Although numerous studies have been performed to meet this objective, there is no commonly accepted guideline on how to select particle size. One possible reason for this gap is the effects of particle size vary when different biomass pretreatment methods are employed. In this study, an assessment on the relationship between particle size and sugar yield was performed for four pretreatment methods. Three particle sizes (1, 4, and 8 mm) of corn stover and switchgrass biomass were used in supercritical CO2, dilute acid (H2SO4), dilute alkaline (Na2CO3), and metal oxide (MgO) pretreatments. Biomass compositional analyses were conducted before and after each pretreatment. Pretreatment solid recovery and sugar recovery rates were calculated. Enzymatic hydrolysis sugar yield and efficiency were used to evaluate the performance of hydrolysis and total sugar yield was used to interpret how much sugar a unit dry weight of biomass (before pretreatment) can yield through pretreatment and enzymatic hydrolysis combined. It was found that particle size was a weak indicator of enzymatic hydrolysis efficiency. There was little value in reducing particle size below 8 mm in order to overcome the resistance imposed by biomass structure on cellulose and xylan hydrolysis.

scholarly journals Study on the Anti-Biodegradation Property of Tunicate Cellulose

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3071
Author(s):  
Yanan Cheng ◽  
Ajoy Kanti Mondal ◽  
Shuai Wu ◽  
Dezhong Xu ◽  
Dengwen Ning ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Conversion Rate ◽  
Crystallinity Index ◽  
Functional Materials ◽  
Degree Of Polymerization ◽  
Crystalline Size ◽  
Crystalline Cellulose ◽  
Marine Animal ◽  
Amorphous Cellulose ◽  
Cellulose Conversion

Tunicate is a kind of marine animal, and its outer sheath consists of almost pure Iβ crystalline cellulose. Due to its high aspect ratio, tunicate cellulose has excellent physical properties. It draws extensive attention in the construction of robust functional materials. However, there is little research on its biological activity. In this study, cellulose enzymatic hydrolysis was conducted on tunicate cellulose. During the hydrolysis, the crystalline behaviors, i.e., crystallinity index (CrI), crystalline size and degree of polymerization (DP), were analyzed on the tunicate cellulose. As comparisons, similar hydrolyses were performed on cellulose samples with relatively low CrI, namely α-cellulose and amorphous cellulose. The results showed that the CrI of tunicate cellulose and α-cellulose was 93.9% and 70.9%, respectively; and after 96 h of hydrolysis, the crystallinity, crystalline size and DP remained constant on the tunicate cellulose, and the cellulose conversion rate was below 7.8%. While the crystalline structure of α-cellulose was significantly damaged and the cellulose conversion rate exceeded 83.8% at the end of 72 h hydrolysis, the amorphous cellulose was completely converted to glucose after 7 h hydrolysis, and the DP decreased about 27.9%. In addition, tunicate cellulose has high anti-mold abilities, owing to its highly crystalized Iβ lattice. It can be concluded that tunicate cellulose has significant resistance to enzymatic hydrolysis and could be potentially applied as anti-biodegradation materials.

Size Reduction of Cellulosic Biomass in Biofuel Manufacturing: Separating the Confounding Effects of Particle Size and Biomass Crystallinity

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Meng Zhang ◽  
Xiaoxu Song ◽  
Pengfei Zhang ◽  
Z. J. Pei ◽  
T. W. Deines ◽  
...  
Keyword(s):  
Particle Size ◽  
Metal Cutting ◽  
Milling Process ◽  
Sugar Yield ◽  
Size Reduction ◽  
Cellulosic Biomass ◽  
Future Research ◽  
Transportation Fuels ◽  
Cellulosic Biofuel ◽  
Reduction Methods

Increasing demands and concerns for reliable supply of liquid transportation fuels make it important to find alternative sources to petroleum-based fuels. Cellulosic biofuels provide one such alternative in the short to medium term. Size reduction is the first step for converting biomass into biofuels. In the literature, there are inconsistent reports about the effects of particle size and biomass crystallinity on sugar yield (proportional to biofuel yield). An important reason for this inconsistence is that particle formation in current size reduction methods is not well controlled, causing the effects of these two variables confounded. One paper investigating the confounding effects of particle size and biomass crystallinity using a metal-cutting (milling) process was previously published in this journal. This paper presents a follow-up study. In this study, a lathe was used to produce poplar wood particles with the same crystallinity but different sizes, making it possible to study the effects of particle size on biofuel yield independently without being confounded by the effects of biomass crystallinity. Results showed that, for the three levels of particle size used in this study, sugar yield increased as particle size became smaller. This study also revealed future research opportunities to understand the effects of size reduction and biomass crystallinity in cellulosic biofuel manufacturing.

Ultrasonic-Vibration Assisted Pelleting for Cellulosic Ethanol Manufacturing: Effects of Particle Size and Moisture Content on Power Consumption

2012 ◽  
Author(s):  
Qi Zhang ◽  
Pengfei Zhang ◽  
Graham Pritchett ◽  
Z. J. Pei ◽  
Meng Zhang ◽  
...  
Keyword(s):  
Particle Size ◽  
Moisture Content ◽  
Power Consumption ◽  
Ultrasonic Vibration ◽  
Cellulosic Ethanol ◽  
Cellulosic Biomass ◽  
Manufacturing Costs ◽  
Transportation Fuels ◽  
Higher Power ◽  
Input Variables

Ethanol produced from cellulosic materials is an alternative to petroleum-based transportation fuels. However, its manufacturing costs are too high to be competitive at present. Raw cellulosic biomass materials have low density, causing their transportation and handling expensive, contributing to high manufacturing costs of cellulosic ethanol. Pelleting can increase the density of cellulosic biomass and reduce their transportation and handling costs. Ultrasonic vibration-assisted (UV-A) pelleting is a new pelleting method. Earlier studies show that moisture content and particle size have significant effects on pellet quality and sugar yield. However, their effects on power consumption in UV-A pelleting have not been studied. Since power consumption directly affects ethanol manufacturing costs, it is desirable to understand how input variables affect power consumption. The objective of this paper is to study effects of moisture content and particle size on power consumption in UV-A pelleting of wheat straw. Results show that higher moisture content and larger particle size result in higher power consumption.

Size Reduction of Cellulosic Biomass in Biofuel Manufacturing: Effects of Biomass Crystallinity and Particle Size

2011 ◽  
Author(s):  
Meng Zhang ◽  
Xiaoxu Song ◽  
P. F. Zhang ◽  
Z. J. Pei ◽  
T. Deines
Keyword(s):  
Particle Size ◽  
Particle Formation ◽  
Size Reduction ◽  
Cellulosic Biomass ◽  
Future Research ◽  
Cellulosic Biofuels ◽  
Transportation Fuels ◽  
Cellulosic Biofuel ◽  
Reduction Methods ◽  
Petroleum Reserves

Gradual depletion of world petroleum reserves and increasing environmental impact of greenhouse gas emissions make it urgent to develop sustainable alternatives to petroleum-based transportation fuels. Cellulosic biofuels provide one such alternative in the short to medium term. In order to convert cellulosic biomass into biofuels, size reduction is a necessary step. In the literature, there are inconsistent reports about the effects of particle size and biomass crystallinity on sugar yield (proportional to biofuel yield). An important reason for this inconsistence is that particle formation in current size reduction methods is not well controlled, causing the effects of these two variables confounded. This paper presents an experimental study on size reduction of poplar wood using a lathe, where particle formation could be well controlled to prevent the effects of these two variables from being confounded. In this study, particle size was controlled by different numbers of slots cut on the workpiece. Particles with the same crystallinity but different particle sizes were produced. This will make it possible to study the effects of particle size on biofuel yield independently, and reveal future research opportunities to understand the effects of size reduction in cellulosic biofuel manufacturing.

Effects of Ultrasonic Treatments on Cellulose in Cellulosic Biofuel Manufacturing: A Literature Review

2010 ◽  
Author(s):  
P. F. Zhang ◽  
Z. J. Pei
Keyword(s):  
Large Scale ◽  
Morphological Structure ◽  
Degree Of Polymerization ◽  
Sugar Yield ◽  
Cellulosic Biomass ◽  
Cellulosic Biofuels ◽  
Crystallinity Degree ◽  
Transportation Fuels ◽  
Cellulosic Biofuel ◽  
Low Efficiency

Cellulosic biofuels are one type of renewable energy, and have been proposed to replace traditional liquid transportation fuels. Cellulosic biomass is the feedstocks in cellulosic biofuel manufacturing. Cellulose accounts for approximately 30% of the total weight in cellulosic biomass. Glucose, one type of monosaccharide convertible to ethanol, can be obtained by hydrolyzing the polymeric structure of cellulose. Currently enzymatic methods are the most common for the hydrolysis of cellulose. However, the low efficiency of enzymatic hydrolysis increases production cost and hinders the large-scale manufacturing of cellulosic biofuels. Ultrasonic treatments applied on cellulosic biomass were found to improve the efficiency of hydrolysis and subsequently increase the sugar yield of hydrolysis. To understand the effects of ultrasonics on cellulose, investigations have been conducted on the effects on cellulose characteristics caused by ultrasonic treatments during hydrolysis. This paper reviews the effects of ultrasonic treatments on cellulose during hydrolysis in terms of sugar yield and some characteristics of cellulose, such as accessibility, crystallinity, degree of polymerization, and morphological structure.

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