2019, Vol. 4, No. 3

Display Method:
Production of Itaconic Acid Through Microbiological Fermentation of Inexpensive Materials
Jing YANG, Hao XU, Jianchun JIANG, Ning ZHANG, Jingcong XIE, Min WEI, Jian ZHAO
2019, 4(3): 135-142. doi: 10.12162/jbb.v4i3.001
Itaconic acid (IA) is a precursor of various chemicals, which has been on the US Department of Energy's list of the top 12 platform chemicals that can potentially be produced from biomass. The IA is mainly produced through a bio-fermentation method with sugar as raw material. However, the high cost and low yield restrict the industrial application of the IA. This review summarized research advances in the IA production from alternative substrates. In particular, the types of substrates as well as existing problems in the IA fermentation, strain breeding, and process regulation were discussed. And it is pointed that decreasing the price of the IA with alternative substrates and increasing the titer through genetic engineering should be further focused on to support the industrialization of the IA. Keywords:itaconic acid; fermentation; Aspergillus terreus; biomass
Original Research
Production and Testing of Biogas Using Cow Dung, Jatropha and Iron Filins
2019, 4(3): 143-148. doi: 10.12162/jbb.v4i3.002
Biogas production was investigated in this study as an alternative to wood as fuel using slurries of cow dung (T1), jatropha fruit exocarp (T2), cattle dung and jatropha fruit exocarp (T3) and cow dung, jatropha fruit exocarp with 10 g of iron filings (T4). The 1000 mL of slurry which included 50 mL of inoculum that compensated for the dead or weak micro-organism was made for each sample. At the end of five weeks, the volume of biogas collected from the samples T1, T2, T3, and T4 when added up, gave 77, 154, 145 and 586 mL, respectively. The sample mixture of cow dung, jatropha fruit exocarp, and iron filings (T4), gave the highest yield of biogas production with an average weekly production of 59 mL/kg for four weeks and on the fifth week about six times emission of biogas was obtained. The production rate of the biogas was rapid after the gestation period and the T4 emerged as the most substantial emission of all the samples producing 350 mL/kg on the fifth week.
ZnCl2 Enhanced Acid Hydrolysis of Pretreated Corncob for Glucose Production: Kinetics, Thermodynamics and Optimization Analysis
2019, 4(3): 149-158. doi: 10.12162/jbb.v4i3.003
The biomass of agricultural wastes as a source of fermentable sugars for biofuels production will address the food security and environmental preservation issues. These wastes are rich in lignocellulosic materials which can be hydrolyzed into fermentable sugars. However, low sugar yield and high energy consumption are some of the challenges faced in the process of hydrolization. This study investigated the low-cost corncob substrate for glucose production by dilute sulphuric acid hydrolysis in the presence of ZnCl2 at temperatures below 100℃ after pretreatment with 10% NaOH. Time dependent hydrolysis data were analyzed by Saeman model, and thermodynamic parameters were obtained using Erying and Arrhenius equations while Box-Behnken model (Design Expert 6.0 version) was used for experimental design. As the substrate concentration increased from 50 mg/L to 150 mg/L, glucose yield increased from 10.4 mg/g to 14.6 mg/g for pretreated corncob while an increase from 3.4 mg/g to 8.6 mg/g was noted for untreated corncob. The hydrolysis rate constant was two orders of magnitude higher than the degradation rate constant. Thermodynamic parameters revealed endothermic process with positive Gibb's free energy of hydrolysis having average values of 84.76 kJ/mol and 79.87 kJ/mol for pretreated and untreated samples respectively. The optimum yield from the model was found to be 177.44 mg/g with 3.94% H2SO4 and 0.43 mol/L ZnCl2 for 200 g/L compared with optimum yield of 46.37 mg/g obtainable without ZnCl2. The results of this study showed that the alkaline pretreatment of corncob increased the accessibility of cellulose from the solid fraction and increased glucose production.
Physico-mechanical Properties of Composite Briquettes from Corncob and Rice Husk
2019, 4(3): 159-165. doi: 10.12162/jbb.v4i3.004
Densification of agricultural residues into briquettes as the alternative renewable feedstock can improve their physico-mechanical and storage properties as solid fuels. This paper presents the physico-mechanical properties of the composite briquettes made from corncob and rice husk. Raw samples of corncob and rice husk were collected, sorted and pulverised into fines of 0.25, 1.00 and 1.75 mm particle sizes. The fines were blended at mixing ratios of 80:20, 70:30, 60:40, and 50:50, bonded with 5% starch on weight percentage basis and compressed at compaction pressures of 25, 50, and 65 kPa to produce the briquette samples, respectively. The briquette made from 80:20 ratio of corncob to rice husk, 0.25 mm particle size and 65 kPa pressure exhibited the highest compressive strength of 111 kN/m2 and the least of 39 kN/m2 from briquette with 50:50 ratio of corncob to rice husk, 1.75 mm particle size and 25 kPa pressure. The briquette made from 50:50 ratio of corncob to rice husk, 0.25 mm particle size and 65 kPa pressure had the highest water resistance capacity, and the least from briquette of 80:20 ratio of corncob to rice husk, 1.75 mm particle size and 25 kPa pressure. The resulting physico-mechanical qualities of the produced corncob and rice husk briquettes suggested that they could be used as the solid fuels for domestic and industrial applications.
Release Profile of Nitrogen During Thermal Treatment of Waste Wood Packaging Materials
Jinsheng GOU, Liuming SONG, Hui LIU, Dandan SHEN, Wanxiao HU, Wenliang WANG, Xueyong REN, Jianmin CHANG
2019, 4(3): 166-176. doi: 10.12162/jbb.v4i3.005
Wood packaging waste with a high recycling value is one of the main components of packaging waste. However, most researches have been focused on natural wood, and less been known about the recycling of wood-based panel waste commonly used in packaging. This paper examined the pyrolysis of common urea-formaldehyde (UF) resin particleboard, including the decomposition characteristics of its nitrogen-containing adhesives, the product types, and how they were generated. The samples and pyrolysis products were analyzed by infrared spectroscopy. The results showed that the UF resin was the main contributor to the release of ammonia (NH3) and hydrogen cyanide (HCN). At low temperatures, more NH3 was released than the HCN, and at high temperatures, the reverse was true. A high heating rate promoted the release of the NH3 and HCN. The UF resin and wood in the particleboard interacted and caused the release of the NH3 and HCN. These results provide a reference for further study of the thermochemical regeneration of wood-based packaging waste.
Antibacterial Nanoparticles with Universal Adhesion Function Based on Dopamine and Eugenol
Huilin XU, Dongyue ZHANG, Jianshu LI
2019, 4(3): 177-182. doi: 10.12162/jbb.v4i3.006
In this work, dopamine methacrylamide (DMA) and eugenyl methacrylate (EMA) were used to synthesize polymeric particles of Poly (DMA-co-EMA) by free radical precipitation copolymerization. These two monomers were modified from dopamine (consisting of the catechol moieties adhering to various materials) and eugenol (with antibacterial property), respectively. The proton nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FT-IR) spectroscopy were applied to confirm the successful synthesis of the two monomers and copolymer. The scanning electron microscope (SEM) images showed the size and morphology of the polymer particles. The results indicated that regular particles with uniform size could be obtained with a monomer feeding ratio of 5:5. The results of antibacterial activity test indicated that the obtained polymer particles have an antibacterial rate over 90% to Eugenia coli.
Synthesis and Application of UV-curable Phosphorous-containing Acrylated Epoxidized Soybean Oil-based Resins
Yun HU, Puyou JIA, Qianqian SHANG, Meng ZHANG, Guodong FENG, Chengguo LIU, Yonghong ZHOU
2019, 4(3): 183-191. doi: 10.12162/jbb.v4i3.007
A novel phosphorous-containing acrylated epoxidized soybean oil-based (P-AESO) resin was developed via the ring-opening reaction of epoxidized soybean oil (ESO) with diphenylphosphinic chloride (DPPC), followed by acrylation of the resulting groups. The chemical structure was characterized by Fourier transform infrared spectroscopy (FT-IR), and 1H nuclear magnetic resonance (1H NMR). Subsequently, the viscosity and volumetric shrinkage of the obtained P-AESO resins were studied. Then the oligomer was formulated into UV-curable coatings, and the mechanical, thermal, and coating properties of the resulting UV-cured bioresins were studied by tensile testing, dynamic mechanical thermal analysis (DMA), thermogravimetric analysis (TGA) coupled with FT-IR spectroscopy (TGA-FT-IR), hardness, adhesion, pencil hardness and chemical resistance. Furthermore, the UV-curing behavior of the P-AESO resin was determined by real-time realtime infrared (RT-IR). Meanwhile, compared with coating from acrylated epoxidized soybean oil (AESO), the P-AESO system coatings showed better volumetric shrinkage, excellent adhesion, and enhanced thermal and glass transition temperature (Tg) while maintaining reasonably final C=C conversions and cross-link density. For instance, the obtained P-AESO/trimethylolpropanetriacrylate (TMPTA) 20 material possessed a volumetric shrinkage of 4.1%, Tg of 115.6℃, char yield of 9.47%, and final C=C conversions of 81.4% respectively, which exhibited superior values than that of the AESO/TMPTA20 material. The improvement of the P-AESO coating performances could contribute to the architectures that combined the structural features of phosphorous-containing rigid benzene. The developed P-AESO resin is promising for applications in the UV-curable coatings.
Spectroscopic/Microscopic Elucidation for Chemical Changes During Acid Pretreatment on Arundo donax
Bingwei CHEN, Xinzhou WANG, Weiqi LENG, Yu'na KAN, Changtong MEI, Shengcheng ZHAI
2019, 4(3): 192-199. doi: 10.12162/jbb.v4i3.008
The Arundo donax is a typical fast-growing species from the family Gramineae, which is widely cultivated in China. With a huge yield of A. donax in China, this plant offers great potential for biofuels production. The different types of organization of cell and the tissue in the A. donax could influence the efficiency of enzymatic hydrolysis. In this study, A. donax was subjected to 0.5% (w/w) sulfuric acid (H2SO4) for pretreatment at 140℃ for 10 min, 20 min, 40 min, and 60 min, respectively. The changes in microstructure, chemical composition, topochemical properties were comprehensively analyzed. Using a series of spectroscopic and microscopic techniques including Fourier transform infrared spectroscopy (FT-IR), X-Ray diffraction (XRD), polarized light microscopy (PLM), and confocal Raman microscopy (CRM) to obtain the correlative structural and chemical information. Analysis results of chemical composition, FT-IR spectra and XRD indicated that with increasing reaction time, more hemicellulose and lignin would be removed. Correspondingly, there was an obvious increase of the cellulose relative crystallinity via extending reaction time. Results of the PLM observations showed that the birefringence gradually dimmed due to the diminishing of the cellulose component. Furthermore, the CRM mapping images showed the lignin component in compound middle lamellar (CML) was difficult to remove relatively as compared with that in secondary walls. These results indicated that the combination of spectroscopic and microscopic elucidation could give an insightful understanding of chemical changes in cellular level during pretreatment.