Maximum Liquid Yield Research Articles

Catalytic pyrolysis of apricot kernel shell over metal supported MCM-41 catalysts obtained by synthesizing sonochemical method

In this study, it is targeted to examine the efficiency of metal supported MCM-41 catalysts on the liquid product yield from pyrolysis process of apricot kernel shell selected as a biomass and to characterize the pyrolysis liquids. In the non-catalytic pyrolysis experiments, the maximum liquid yield is obtained as 21.41 % at 500 °C. At the determined optimum condition, catalytic pyrolysis process of the biomass sample is performed with metal supported MCM-41 catalysts synthesized by sonochemical method (metal: aluminium, cobalt, iron) at different ratios to biomass (1 and 2 wt %). The pyrolysis procedures of apricot kernel shell are carried out in a tubular fixed-bed reactor at different pyrolysis temperatures. The use of catalysts improved both the liquid product (tar) yield and tar quality in respect to the calorific value, the distribution of hydrocarbons and the elimination of oxygenated groups. The results revealed that all metal-supported MCM-41 catalysts, especially the Fe-MCM-41 catalyst ratio of 2, showed an excellent catalytic ability for thermal conversion of biomass. In the catalytic pyrolysis experiments carried out at 500 °C, 75.84 % conversion to liquid and gaseous products was obtained using 2 % Fe-MCM-41 catalyst, and the calorific value of the liquid product obtained was determined as 40.96 MJ/kg. The functional group analyses in the structure of the liquid products are characterized using FT-IR spectroscopy, and the distributions of the aliphatic/aromatic fractions of the liquid products are characterized using GC-MS technique. The H/C ratio of the liquid product obtained from catalytic pyrolysis is between light and heavy petroleum products and also has lower oxygen content and higher calorific value, indicating the potential of metal-supported MCM-41 catalyst for renewable hydrocarbon production from apricot kernel shell.

Thermo-catalytic co-pyrolysis of waste biomass and non-recyclable polyethylene using ZSM-5 into renewable fuels and value-added chemicals

The present study deals with thermo-catalytic co-pyrolysis of peanut shells (PS) and non-recyclable polyethylene (NRPE) using ZSM-5 at varying ratios (5, 10 and 15 wt%). A tubular fixed bed reactor is used to pyrolyse at 500 °C, 50 °C min−1 heating rate and 100 mL min−1 inert gas flow rates. The feedstock was characterized via proximate analysis, elemental analysis, higher heating value (HHV), biochemical analysis, thermogravimetric analyser (TGA), Fourier transforms infrared spectroscopy (FTIR) viscosity, density, Gas chromatography-mass spectrometry (GC-MS), BET surface area, water holding capacity (WHC). Co-pyrolysis results confirmed maximum liquid yield (34.50 %) at 10 wt% of NRPE; however, adding 10 wt% ZSM-5 again boosted the liquid oil yield by 7.87 wt%. Pyrolytic oil characterization results confirmed that adding NRPE and ZSM-5 at 10 wt% decreased viscosity, acidity, and density. However, carbon content, heating value and ash content increased. FTIR examinations of PS confirmed hydrocarbons, acids, water, and oxygenated compounds. GC-MS results were confirmed by adding NRPE and ZSM-5 at 10 wt%; hydrocarbon and furfural increased by 5.31 and 5.46 %, whereas 6.01 % acids and oxygenated compounds decreased, respectively. The results of the char characterisation further supported the findings that adding NRPE (10 wt%) to PS enhanced carbon content and HHV by 11.86 % and 4.35 MJ kg−1 and decreased ash content, oxygen content, and bulk density by 0.75 %, 10.21%, and 71.98 kg m−3, respectively.

Influence of retention time and catalyst concentrations on catalytic pyrolysis yields of polyethylene and polystyrene

ABSTRACT The present work focuses on enhancing the liquid fraction yields having hydrocarbons in the diesel fuel range from pyrolysis of PS/PE (1:1 wt.%) under the influence of ZSM–5 catalysts in an autoclave reactor. The pyrolysis product yields and their compositions were investigated for varied catalyst concentrations (0%, 5%, 7.5%, and 10%), reaction temperatures (250–500°C), and retention times (20–60 min). The physical and chemical characterization of the feedstocks, catalysts, and thermally and catalytically derived oils were carried out along with elemental analysis of the liquid products. It was observed that 7.5% catalyst concentration exhibited the maximum liquid fraction yields (71.2 wt.%) at 350°C and a retention time of 30 min. Catalytic cracking with a retention time of 20–30 min produced maximum liquid yields with aromatic, aliphatic, and isomerized hydrocarbon contents of 42.9%, 30.15%, and 14.3%, respectively. Expedite weakening of the catalytic activity of the ZSM-5 catalyst was observed with process retention time higher than 30 min. The calorific values of catalytically derived oils were found to be in the range of 44.2–44.8 MJ/kg, and their carbon numbers were between C11 and C19. Thus, these characteristics make these oils a potential candidate to be used as an alternative to diesel fuel. Further, the higher proportions of aromatics and aliphatic compounds present in catalytically derived oils compared to that obtained from thermal pyrolysis affirmed its superiority as a potential diesel substitute.

Challenges and Perspectives of the Conversion of Lignin Waste to High-Value Chemicals by Pyrolysis

The pyrolysis process is a thermochemical conversion reaction that encompasses an intricate array of simultaneous and competitive reactions occurring in oxygen-depleted conditions. The final products of biomass pyrolysis are bio-oil, biochar, and some gases, with their proportions determined by the pyrolysis reaction conditions and technological pathways. Typically, low-temperature slow pyrolysis (reaction temperature below 500 °C) primarily yields biochar, while high-temperature fast pyrolysis (reaction temperature 700–1100 °C) mainly produces combustible gases. In the case of medium-temperature rapid pyrolysis (reaction temperature around 500–650 °C), conducted at very high heating rates and short vapor residence times (usually less than 1 s), the maximum liquid yield can reach up to 85 wt% (on a wet basis) or achieve 70 wt% (on a dry basis), with bio-oil being the predominant product. By employing the pyrolysis technique, valuable utilization of tobacco stem waste enriched with lignin can be achieved, resulting in the production of desired pyrolysis products such as transportation fuels, bio-oil, and ethanol. The present review focuses on catalytic pyrolysis, encompassing catalytic hydropyrolysis and catalytic co-pyrolysis, and meticulously compares the impact of catalyst structure on product distribution. Initially, we provide a comprehensive overview of the recent pyrolysis mechanism of lignin and tobacco waste. Subsequently, an in-depth analysis is presented, elucidating how to effectively design the catalyst structure to facilitate the efficient conversion of lignin through pyrolysis. Lastly, we delve into other innovative pyrolysis methods, including microwave-assisted and solar-assisted pyrolysis.

Experimental and modeling studies of intermediate pyrolysis of wood in a laboratory-scale continuous feed retort reactor

Experiments and simulations in Aspen Plus® were performed to study the intermediate pyrolysis of wood in a continuous-feed retort reactor. The experiments were conducted at temperatures of 450, 500, and 650 °C, wood particle sizes of <1.4 mm, and reactor feeding rate of 0.15 kg/h. The experiment recorded a maximum liquid yield of 44.2 wt% at a pyrolysis temperature of 450 °C, while the simulation predicted a maximum yield of 49.1 wt% at 415 °C. Similar results were also reported in other studies. The ultimate analysis of the biochar produced was determined experimentally and by simulation. Results obtained from the experiment and the model were in good agreement. The model's ability to predict the composition of bio-oil was demonstrated through a comparison of its predicted distribution with literature. Furthermore, the study revealed that prolonged char presence in the retort improved biochar quality instead of increasing volatile yields.

Optimization of iron-based catalyst for partial upgrading of Athabasca Bitumen: The role of Fe oxidation state, particle size, and concentration

The present investigation examines the prospective application of Fe-based catalysts for catalyzing the partial upgrading of Athabasca oil sand bitumen, aiming for developing an economically viable and environmentally sustainable process. The primary focus is to analyze the impact of the oxidation state of iron, catalyst particle size, and catalyst concentration on partial upgrading efficiency to optimize bitumen resource utilization without the need of an external source/supply of hydrogen gas using an autoclave reactor. The experimental results demonstrate that Fe-based catalysts, particularly those with lower oxidation states such as FeS, FeO, and Fe3O4, significantly improve the oil quality and reduce bitumen’s viscosity through increasing saturates and substantially reducing the asphaltene fractions. Furthermore, it is also identified that those catalysts can promote hydrogenation and cracking reactions that transform heavier fractions into lighter ones while achieving up to 59% vacuum residue conversion. A comprehensive screening process using Minitab statistical software was made to identify the best catalyst based on the catalyst’s oxidation state, concentration, and particle size range. As a result, Fe3O4 nanoparticles at a 0.5 wt% loading have been identified as the optimal catalyst combination for achieving the maximum liquid yield, while simultaneously producing the minimum asphaltene content, and maximum viscosity reduction. An assessment of the fresh and spent Fe3O4 catalyst yielded valuable insights concerning the catalytic partial upgrading of bitumen, unveiling a reaction mechanism involving iron catalyst sulfidation, desulfurization reactions, CH scission, and hydrocarbon cracking, in addition to the formation of coke. The potential role of various alloy materials employed in the fabrication of reactors for bitumen partial upgrading has also been studied and compared, discussing their unique advantages and limitations in terms of product quality and liquid yield. The findings presented in this study contribute significantly to the development of more efficient and sustainable upgrading processes, paving the way for optimizing catalyst properties for bitumen upgrading applications and providing a valuable perspective on the role of catalysts in the upgrading of heavy oils.

Thermocatalytic pyrolysis of agriculture waste biomass for the production of renewable fuels and chemicals

ABSTRACT The present work highlights the thermocatalytic pyrolysis of three different waste biomasses (Groundnut Stalk, Indian Rosewood, and Rice Straw) using meso and microporous catalysts for the effective conversion to fuels and chemicals. Thermocatalytic pyrolysis was found to be highly significant under optimum conditions (Temperature = 500°C, Heating rate = 90°C/min, Biomass particle size = 0.4 mm, and Sweeping gas flow rate = 100 mL/min). All the synthesized catalysts (KIT-6, NbKIT-6, and ZIF-8) were found to be highly efficient, and the maximum liquid yield was observed at 20 wt% of catalyst loading, i.e. 49.35% (KIT-6); 56.57% (NbKIT-6); and 52.74% (ZIF-8), respectively. The results revealed that compared to KIT-6, the maximum liquid yield was observed with NbKIT-6 catalyst i.e. 56.57% (Groundnut Stalk); 58.45% (Indian Rosewood); and 57.57% (Rice Straw), respectively. The proposed strategy will be highly economical and sustainable and the selected biomass could be a promising alternative and renewable energy source.

Conversion of low-density polyethylene into monocyclic aromatic hydrocarbons through continuous microwave pyrolysis with ex-situ dual-catalyst beds

The single-use of polyolefins-based individual protective equipment has led to the rapid generation of substantial plastic waste. This study aimed at cleaner disposal of the polyolefin waste, and carried out the continuous microwave pyrolysis (CMP) of low-density polyethylene (LDPE) over dual-catalyst beds of MCM-41 and HY. The dual-catalyzed trial was able to produce more condensate fractions with higher selectivity of monocyclic aromatic hydrocarbons (MAHs), compared with using only MCM-41 or HY zeolite. It was because the larger pore size of the MCM-41 catalyst (4.00 nm) could crack long-chain polyolefin intermediates into shorter chains. This alleviates steric and diffusional resistance while entering and exiting the micropores of the HY zeolite (0.74 × 0.74 nm). The maximum liquid yield (63.75 wt%) and MAHs selectivity (78.21%) were achieved at a catalysis temperature of 450 °C, feedstock to catalyst ratio of 8:3, and HY to MCM-41 ratio of 2:1. In addition, the performance of the CMP reactor was also compared favorably with the batch microwave pyrolysis (BMP) reactor under the same conditions. It has been found that the CMP reactor generated more MAHs products, whereas the BMP reactor was more selective for the generation of polycyclic aromatic hydrocarbons (PAHs) and gas products. The combination of CMP and the co-catalysis process offers new insight into sustainable management and value-added recovery of medical plastic waste.

The biochar, and pyrolysis liquid characteristics, of three indigenous durian peel; Monthong, Puangmanee, and Bacho

Durian peel is a type of biomass derived from agricultural residues, which are found in abundant in Thailand. This study aims to investigate the thermal and chemical properties of three indigenous durian peels, namely Monthong (MDP), Puangmanee (PDP), and Bacho (BDP), as well as the characteristics of biochar and pyrolysis liquid derived from slow pyrolysis of the durian peel. MDP had the greatest volatile matter and fixed carbon content, with 73.97 and 18.43 wt%, respectively. MDP was applied for further research in order to produce biochar and pyrolysis liquid at pyrolysis temperatures of 400 and 600 °C. The maximum biochar yield was 36.01% at 400 °C, while the maximum pyrolysis liquid yield was 37.25% at 600 °C. The largest high heating value of biochar (24.48 MJ kg−1) was obtained at 600 °C more than the high heating value of feedstock (14.32 MJ kg−1). Biochar obtained at 400 °C can be categorized as fertilizer class 4, while biochar obtained at 600 °C can be classified as carbon storage class 2 using the IBI biochar classification tool. The quality of the pyrolysis liquid was determined to be of 3.14 pH and 1.052 g mL−1 specific gravity at a pyrolysis temperature of 600 °C, which meets Thailand standards. As a result, both 400 °C and 600 °C pyrolysis liquids produced significant chemicals that are employed in a variety of industries. Consequently, this research is strongly recommended to be expanded to produce high-quality durian peel biochar and pyrolysis liquid.

Production of gasoline octane booster aromatics benzene, toluene and ethylbenzene from multiphase catalytic pyrolysis of mixed waste expanded polystyrene and high density polyethylene

The main objective of this study is to enhance the valuable octane booster aromatics benzene, toluene, and ethylbenzene (BTE) and reduction of styrene in the fuel oil obtained from the pyrolysis of equally mixed waste expanded polystyrene (WEPS) and waste high density polyethylene (WHDPE). This research article, demonstrated the pyrolysis of equally mixed (50 wt.%:50 wt.%) waste expanded polystyrene (WEPS) and waste high-density polyethylene (WHDPE) followed by in situ-hydrogenation and aromatization in a small laboratory scale reactor for the production of value added commodity and gasoline octane boosters mainly benzene, toluene, and ethylbenzene (BTE). Three reactor arrangements i.e., liquid phase/L-type, vapour phase/V-type, and multiphase/M-type were used for conducting the catalytic pyrolysis of feedstock using ZSM-5, ammonium powder as a catalyst. The maximum liquid yield of 87.41 wt.% was obtained for thermal pyrolysis at a temperature of 650°C and at a heating rate of 15°C/min. Whereas, the maximum liquid yield of 82.65 wt.% was obtained for liquid phase/L-type catalytic pyrolysis at a temperature of 600°C, and at a heating rate of 15°C/min. On the other side, vapour phase/V-type and multiphase/M-type catalytic pyrolysis produced a maximum liquid yield of 78.62 wt.% and 74.07 wt.%, respectively at a reaction temperature of 550°C and at the same heating rate. The pyrolysis oil obtained from thermal pyrolysis contained lowest BTE content of 10.43 wt.% and highest styrene content of 66.25 wt.%. Whereas, the highest BTE content of 30.16 wt.% and lowest styrene content of 53.32 wt.% was found in pyrolysis oil obtained from multiphase/M-type catalytic pyrolysis. The quantitative measurement of BTE and styrene content in the pyrolysis oil was made by the gas chromatography (GC) in a flame ionization detector (FID) mode.

Use of Response Surface Methodology in Optimizing the Production yield of Biofuel from Cashew Nut Shell through the Process of Pyrolysis

A fixed bed pyrolysis reactor was used to pyrolyze Cashew nut shell (CNS). Response Surface Methodology (RSM) was then used to study the pyrolysis process. One Factor at a Time (OFAT) experiment was applied using different factors and levels. The OFAT results showed that the highest pyrolysis liquid yield was 57.8 wt.%. Two levels from each factor were chosen to run the RSM (applying Central Composite Design (CCD)) by forming two levels three factors (23) design. A quadratic model suggested by the Design Expert (version 11) software was used to predict the yield. The maximum liquid yield from the RSM was 61.3 wt. %.

Thermo chemical conversion of cedar wood by pyrolysis technology for bio-oil

The conversion of cedar wood which is abundantly found in the forests of Japan, into biofuels and chemicals by externally heated fixed-bed pyrolysis reactor has been taken into consideration in this study. The selected solid biomass in particle form were fed into the reactor by gravity feed type reactor feeder. The output products were liquid (oil), solid char, and gas. The liquid and char products were collected separately while the gas was flared into the atmosphere. The process conditions were found to influence the product yields significantly. The maximum liquid yields were 48 wt% of solid particles at reactor temperature 450 °C for N2 gas flow rate 6 L/min, feed particle size 1180–1700 µm, and running time 30 min. The liquid product obtained at this optimum condition was characterized by physical properties, chemical analysis, and gas chromatograph mass spectrometry techniques. The results show that it is possible to obtain liquid product from cedar wood that are comparable to petroleum fuels and other valuable chemicals.

Pyrolysis of dealkaline lignin to phenols by loading grinding beads in a rotary kiln reactor

The pyrolysis of dealkaline lignin to phenols was performed in a rotary kiln reactor using grinding beads as filler. The effects of pyrolysis temperature and the amount and material of grinding beads on the liquid yield and composition were investigated. The results showed that the use of the rotary kiln reactor loaded with grinding beads could improve the efficiency of lignin pyrolysis. Temperature had a considerable influence on the pyrolysis process. The maximum liquid yield of 52.10 % was obtained at 500 °C and carrier gas flow rate of 300 mL min−1. Compared with other grinding beads, γ-alumina spheres could result in higher liquid yield and selectivity for guaiacols and alkylphenols. The liquid yield increased significantly with the use of grinding beads and increased with the increase in the number of grinding beads. However, both liquid yield and selectivity for guaiacol decreased when the volume ratio of grinding beads to reaction chamber increased from 1:2–2:3. The present study confirms the facilitative effect of grinding beads on the pyrolysis reaction, with the maximum increase of 86.87 % liquid yield and 12.58 % selectivity for guaiacol and alkyl phenols.

Ni/SiO2 catalysts for polyolefin deconstruction via the divergent hydrogenolysis mechanism

Noble metal-based hydrogenolysis is emerging as a key chemical deconstruction technology of polyolefins into valuable products. Still, the catalyst cost and availability are significant barriers to handling the large volume of plastics. Cheap earth-abundant metals have been deemed inactive for polyolefin hydrogenolysis. Herein, we report that Ni/SiO2 is active in deconstructing low-density polyethylene to n-alkanes (C6-C35) at mild conditions (300 °C, 30 bar H2) with maximum liquid yields of 65 wt%. We expose a new mechanism of long-alkane hydrogenolysis that encompasses chain location-dependent single and multiple C-C bond cracking events and rationalizes product selectivity and molecular weight dependence. Ni/SiO2 catalysts are reusable and can handle multiple plastics producing feedstock-dependent products (i.e., n-alkanes, iso-alkanes, cyclics, aromatics, etc.). The findings broaden the scope of viable catalysts polyolefin hydrogenolysis and unleash the potential to manage the volume of plastic waste.

Effects of Heating Rate and Temperature on the Yield of Thermal Pyrolysis of a Random Waste Plastic Mixture

Effects of heating rate and temperature on thermal-pyrolytic yield of a plastic-waste mixture were studied in a semi-batch reactor. The temperature in the range of 380–460 °C and heating rates of 10, 19, and 28 °C/min were evaluated through an experimental multi-level design. The results show that higher temperatures or lower residence time reduce the yield of pyrolytic oil at the expense of increasing the yield of gaseous products. The maximum liquid yield was 69%, obtained at 410 °C and a heating rate of 10 °C/min. The composition of pyrolytic oil covers a wide range of hydrocarbons; thus, a fractionation is necessary before using it as fuel in internal combustion engines. The fractionation process yielded 21.12 wt% of light fraction (gasoline-like), 56.52 wt% of medium fraction (diesel-like), and 22.36 wt% of heavy fraction (heavy diesel-like). The light fraction has an octane index and caloric value within the range of the typical gasoline values. On the other hand, the cetane index and caloric value of the medium fraction meet the requirements of the standards for diesel.

Production of liquid fuel from co-pyrolysis of jatropha cake with tyre waste

This paper introduces the technique that can be used to produce liquid fuel in high quantity, and the technique is called co-pyrolysis technique. Co-pyrolysis is a process which involves two or more materials as feedstock. To the best of my knowledge, there have not been any research about the co-pyrolysis of Jatropha seed cake with tyre waste. The feedstock materials were Jatropha cake and tyre waste. The characterization of the feedstock materials were carried out based on proximate and ultimate analysis. The Jatropha cake with tyre waste were in particle form and were pyrolyzed in an externally heated fixed bed reactor with nitrogen as an inert gas. The reactor was heated by means of electrical furnace. The products of the experiment were: liquid fuel, char and gas. The ratio of jatropha cake to tyre waste materials were 1:1, 1:2 and 1:3 respectively. The parameters that has more influence on the production of liquid fuel yields includes: feed ratio, temperature and reaction time. The maximum liquid yield obtained from the co-pyrolysis of Jatropha cake with tyre waste was 68.0 wt% (that is at the parameters of: feed ratio 1:1, temperature 500 oC and reaction time of 45 minutes).

Synthesis and efficient use of low‐cost natural red clay catalyst for the production of upgraded fuel oil using pyrolysis of waste expanded polystyrene and in situ vapour phase hydrogenation

The waste expanded polystyrene (WEPS) was subjected to the pyrolysis and in situ hydrogenation process in a laboratory fabricated innovative reactor on a red clay catalyst in the temperature range of 400°C to 700°C. Five different catalysts were synthesized from the eco-friendly and non-toxic red clay, that is, red clay in natural form (RC), red clay calcined at 600°C (RC-600), red clay calcined at 700°C (RC-700), red clay calcined at 800°C (RC-800), and red clay calcined at 900°C (RC-900). The catalytic pyrolysis of WEPS, in situ hydrogenation, and aromatization were performed keeping the synthesized catalyst in different reactor arrangements, that is, liquid phase/X-type, vapour phase/Y-type, and multiphase/XY-type. The raw and calcined red clay catalysts were characterized by various characterization techniques such as SEM-EDX, BET, XRD, and FTIR. The calcination temperature greatly influenced the surface morphology and surface area of the red clay catalysts. The surface morphology of calcined red clay catalyst RC-800 shows nano cluster form of particles with very high porosity. The highest surface area of 29.25 m2/g and highest silica content of 56.82 wt% were found for the RC-800 catalyst. Furthermore, the XRD analysis ensured the presence of illite-micas, α-quartz, κ-kappa alumina, δ-delta alumina, and θ-theta alumina in the RC-800 catalyst only. The presence of strong Bronstedacid sites in RC-800 catalyst was confirmed by the FTIR analysis. The highest liquid yield of 94.37 wt% was obtained for the thermal pyrolysis of WEPS at the optimum temperature of 650°C and heating rate of 15°C/min. The maximum BTE content of 11.38 wt% was recorded for the pyrolysis oil obtained from the thermal pyrolysis of WEPS at the same optimum conditions. On the other side, the highest liquid yield of 88.82 wt% was obtained for the X-type pyrolysis at the optimum temperature of 600°C and heating rate of 15°C/min using red clay catalyst RC-800. The Y-type and XY-type pyrolysis produced maximum liquid yield of 80.81 wt% and 79.47 wt%, respectively, at the optimum temperature of 550°C and at heating rate of 15°C/min using the same red clay catalyst RC-800. However, the multiphase/XY-type pyrolysis produced the highest BTE content of 27.62 wt% and lowest styrene content (60.75 wt%) at a temperature of 550°C using RC-800 catalyst among all types of pyrolysis. The maximum styrene content of 84.74 wt% was found in pyrolysis oil obtained from thermal pyrolysis of WEPS at optimum conditions. The styrene content obtained reduced significantly from 68.83 wt% to 60.75 wt% when the reactor arrangement was changed from X-type to XY-type. The pyrolysis oil obtained from XY-type/multiphase pyrolysis was found suitable for the use in internal combustion (IC) engine.

Effect of low-temperature hydrothermal treatment of HZSM-5 extrudates on the production of deeply-deoxygenated bio-oil via ex-situ catalytic fast pyrolysis of biomass

Catalytic fast pyrolysis (CFP) of biomass has high potential for producing deoxygenated bio-oil in one single process. HZSM-5 is a widely used catalyst for this purpose and various parameters have already been extensively investigated on this catalytic material. Limited studies were performed on the effect of low-temperature hydrothermal treatment of the catalyst with none being applied in ex-situ CFP in a lab-scale pyrolysis unit. The current paper therefore reports the investigation of HZSM-5 characteristics and activities when hydrothermally treated by steam at 550 °C for 5 h. The treatment modified the catalyst in a positive way that can increase 30% of the non-aqueous catalytic bio-oil yield. A maximum organic liquid yield of 11.4 wt% was achieved with 6.7 wt% being heavy fraction and 4.7 wt% being light fraction. These heavy and light bio-oils had very low oxygen contents of 4.3 and 1.6 wt%, respectively. This is equivalent to 93% oxygen removal compared to its corresponding non-catalytic bio-oil. Based on the elemental, FTIR, and GC/MS analyses, the hydrothermal treatment slightly increased the bio-oil oxygen content. Characterization of the catalysts reveal irreversible catalyst deactivation by dealumination. The severity of the deactivation increased continuously with higher amount of biomass being fed to the process. However, the catalyst deoxygenation ability was still acceptable for producing partially-deoxygenated bio-oil even after applying the biomass-to-catalyst ratio of 20.5.

Effect of Pyrolysis Temperature on the Physicochemical and Combustion Properties of Desert Date (Balanite Aegyptiaca) Bio-Char Briquette

The depletion in fossil fuels usage requires a replacement to a sustainable bio-fuels source. This research investigated the yield of three kinds of products of the fast pyrolysis of desert date shell in a fabricated fixed bed reactor by varying the pyrolysis temperature from 500 to 800 °C. The purpose of the experiment was to produce briquettes from the bio-chars bonded with cassava starch and gum arabic. The physicochemical properties of briquettes were characterized using ASTM and DIN stan dards while the calorific values and the fuel properties such as ignition time, boiling time, cooking efficiency and fuel efficiency were determined. The maximum yield of pyrolysis liquid was obtained around 49.08 wt% as pyrolysis temperature reached 600 °C and the highest yield of gases was obtained at 23.20 wt% at 800 °C . Maximum yield of char was obtained at 500 °C around 48.20 wt% and started to decrease as temperature increases. All the properties investigated showed that starch bonded briquettes have better physicochemical and fuel qualities than the gum arabic bonded briquettes. It was observed that the best starch bonded briquettes were obtained at 800 o C temperature range while the best gum arabic bonded briquette was obtained at 800 °C temperature range. It was observed that the briquettes produced from pyrolysis derived biochar have great potential as an alternative solid fuel.

Optimization of process parameters using response surface methodology for maximum liquid yield during thermal pyrolysis of blend of virgin and waste high-density polyethylene

Optimization of process parameters using response surface methodology for maximum liquid yield during thermal pyrolysis of blend of virgin and waste high-density polyethylene