scholarly journals Using a Fixed-Bed of Wheat Straw-Derived Biochar to Enhance Cracking of a Mixture of Four Pyrolysis Vapor Model Compounds

Author(s):  
Christian Di Stasi ◽  
Darío Alvira ◽  
Joan J. Manyà ◽  
Belén González

The aim of this work is to test the capacity of a biochar-based porous material to enhance the cracking of pyrolysis vapors. Biochar is a sustainable material obtained from renewable resources and a relatively low cost alternative to the metal-containing catalysts used in catalytic cracking.

2021 ◽  
Vol 24 (1) ◽  
pp. 1-7
Author(s):  
Alaa Taha ◽  
Khalid M. Mousa

The intention of this study was to explore the efficiency and feasibility of adsorption of Reactive Blue dye (H3R) used in textile industries using Raw wheat straw (RWS) and Modified wheat straw (MWS) as a low-cost adsorbent. Wheat straw was modified using cationic surfactant (CTAB) to study the improvement of dye removal. The properties of Raw and Modified wheat straw are studied by means of Fourier transform infrared (FTIR) and scanning electron microscope (SEM) analyses to determine the functional groups and the nature of their surface. Continuous experiments were done by fixed-bed column to study the characteristics of the breakthrough curve using different bed heights and flow rates. Results showed that the breakthrough time increases with increasing bed height and decreasing flow rate, in turn results into higher removal capacity. Results also showed a higher flow rate lead a lower adsorption capacity due to insufficient residence time. Bed depth service time model (BDST), Adam-Bohart and Thomas models were used to predict the breakthrough curves and to determine the adsorption capacity of the column. The highest bed capacity of 12.95 and 32.2 mg/g for MWS was obtained using 10 mg/L, 10 cm bed height at 10 mL/min and 30 mL/min respectively.


2014 ◽  
Vol 625 ◽  
pp. 259-262 ◽  
Author(s):  
Farrukh Jamil ◽  
Bawadi Abdullah ◽  
Murni Melati Ahmad ◽  
Abrar Inayat ◽  
Suzana Yusup

Kinetic study on the transformation of model compounds of bio-oil into less oxygenated liquid product was performed. A fixed bed continuous reactor was used for the catalytic cracking of bio-oil model compounds at the temperatures of 300°C, 400°C and 500°C under atmospheric pressure. HZSM-5 was used as the catalyst with the oil to catalyst ratio of 15. The kinetic behavior of the catalytic cracking of bio-oil was represented by a 3-lumped model. The kinetic parameters were calculated using an error minimization approach based on least square method. The results indicated that rate of formation for both gaseous products as well as for liquid product (LP) increased when the temperature increased. The activation energy for liquid product was higher compared to that for gaseous product. The order of reaction was in a fraction form which implies the complex nature of the cracking reaction.


Author(s):  
Christian Frilund ◽  
Esa Kurkela ◽  
Ilkka Hiltunen

AbstractFor the realization of small-scale biomass-to-liquid (BTL) processes, low-cost syngas cleaning remains a major obstacle, and for this reason a simplified gas ultracleaning process is being developed. In this study, a low- to medium-temperature final gas cleaning process based on adsorption and organic solvent-free scrubbing methods was coupled to a pilot-scale staged fixed-bed gasification facility including hot filtration and catalytic reforming steps for extended duration gas cleaning tests for the generation of ultraclean syngas. The final gas cleaning process purified syngas from woody and agricultural biomass origin to a degree suitable for catalytic synthesis. The gas contained up to 3000 ppm of ammonia, 1300 ppm of benzene, 200 ppm of hydrogen sulfide, 10 ppm of carbonyl sulfide, and 5 ppm of hydrogen cyanide. Post-run characterization displayed that the accumulation of impurities on the Cu-based deoxygenation catalyst (TOS 105 h) did not occur, demonstrating that effective main impurity removal was achieved in the first two steps: acidic water scrubbing (AWC) and adsorption by activated carbons (AR). In the final test campaign, a comprehensive multipoint gas analysis confirmed that ammonia was fully removed by the scrubbing step, and benzene and H2S were fully removed by the subsequent activated carbon beds. The activated carbons achieved > 90% removal of up to 100 ppm of COS and 5 ppm of HCN in the syngas. These results provide insights into the adsorption affinity of activated carbons in a complex impurity matrix, which would be arduous to replicate in laboratory conditions.


Author(s):  
Changzhou Chen ◽  
Dichao Wu ◽  
Peng Liu ◽  
Haihong Xia ◽  
Minghao Zhou ◽  
...  

Noble-metal catalytic cleavage of the ether bonds in lignin to obtain aromatic chemicals had achieved great success, and development of a low-cost and efficient catalyst was crucial. Herein, NixLay/CNT was...


Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 896 ◽  
Author(s):  
Qiqi Fan ◽  
Guangping Han ◽  
Wanli Cheng ◽  
Huafeng Tian ◽  
Dong Wang ◽  
...  

In this work, an easy way to prepare the polylactic acid (PLA)/wheat straw fiber (WSF) composite was proposed. The method involved uses either the dopamine-treated WSF or the two-step montmorillonite (MMT)-modified WSF as the filler material. In order to achieve the dispersibility and exfoliation of MMT, it was modified by 12-aminododecanoic acid using a two-step route. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were performed to characterize the modified MMT and the coated WSF. As for the properties of PLA/WSF composites, some thermal (using Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis) and mechanical properties (flexural, tensile, and impact) were analyzed. The results showed that the dopamine was successfully coated onto the WSF. Furthermore, Na-MMT was successfully transformed to organo-montmorillonite (OMMT) and formed an exfoliated structure. In addition, a better dispersion of MMT was obtained using the two-step treatment. The interlayer spacing of modified MMT was 4.06 nm, which was 123% higher than that of the unmodified MMT. Additionally, FT-IR analysis suggested that OMMT diffused into the PLA matrix. The thermogravimetric analysis (TGA) showed that a higher thermal stability of PLA/WSF composites was obtained for the modified MMT and dopamine. The results also showed that both the dopamine treated WSF and the two-step-treated MMT exhibited a positive influence on the mechanical properties of PLA/WSF composites, especially on the tensile strength, which increased by 367% compared to the unmodified precursors. This route offers researchers a potential scheme to improve the thermal and mechanical properties of PLA/WSF composites in a low-cost way.


2018 ◽  
Vol 78 (8) ◽  
pp. 1693-1703 ◽  
Author(s):  
Jordana Georgin ◽  
Fernanda Caroline Drumm ◽  
Patrícia Grassi ◽  
Dison Franco ◽  
Daniel Allasia ◽  
...  

Abstract Araucaria angustifolia bark (AA-bark), a waste generated in wood processing, was evaluated as a potential adsorbent to remove Gentian Violet (GV) dye from aqueous solutions. The AA-bark presented an amorphous structure with irregular surface and was composed mainly of lignin and holocellulose. These characteristics indicated that the adsorbent contains available sites to accommodate the dye molecules. The GV adsorption on AA-bark was favored at pH 8.0 with adsorbent dosage of 0.80 g L−1. Pseudo-nth order model was adequate to represent the adsorption kinetics of GV on AA-bark. A fast adsorption rate was verified, with the equilibrium being attained within 30 min. Equilibrium data were well represented by the Langmuir model. The maximum adsorption capacity was 305.3 mg g−1. Adsorption was spontaneous, favorable and endothermic. AA-bark was able to treat a simulated dye house effluent, reaching color removal values of 80%. An excellent performance was found in fixed bed experiments, where the length of the mass transfer zone was only 5.38 cm and the breakthrough time was 138.5 h. AA-bark can be regenerated two times using HNO3 0.5 mol L−1. AA-bark can be used as a low-cost material to treat colored effluents in batch and fixed bed adsorption systems.


2018 ◽  
Vol 7 (2) ◽  
pp. 110-112
Author(s):  
Sasikumar Gnanasekaran ◽  
Sivasangari Ayyappan

Natural fibres namely sisal, jute, kenaf, hemp, abaca and banana are mainly used in industries for developing Natural fibres composites. They find many applications such as automobiles, furniture, packing and construction due to many merits such as their low cost, good mechanical properties, non-toxic, low weight, less damage to processing equipment, improved surface finish, abundant and renewable resources. The objective of this paper is to review the applications of various kenaf fibre reinforced polymer composites which will provide a base for further research in this area.


2018 ◽  
Vol 32 (5) ◽  
pp. 5910-5922 ◽  
Author(s):  
Fuwei Li ◽  
Shilei Ding ◽  
Zhaohe Wang ◽  
Zhixia Li ◽  
Lin Li ◽  
...  

Author(s):  
Daud Mustafa Minhas ◽  
Sajjad Hussain

Increasing consumer demand of electricity is difficult for the conventional power system network to handle, regarding both cost and infrastructure. Instead of expanding the expensive infrastructure, power engineers are now focusing on improving efficiencies and effectiveness of existing power networks. This chapter specifically focuses on low cost electricity supply, by introducing the novel concept of digital energy management system in hybrid AC/DC micro-grid. It is assumed that grid is partially powered by time varying renewable resources. The concept of minimizing time average electricity cost is introduced by efficient utilization of these renewable resources and by making the load demands more flexible to operate while taking converter losses into account. Real time pricing model is introduced to elaborate the advantage of time-of-use pricing. Control decisions will be achieved by proposing a load scheduling and hybrid switching (LSHS) algorithm. This algorithm will be capable of supplying low cost electricity while serving the load demands under specific delay bounds.


Sign in / Sign up

Export Citation Format

Share Document