Characteristics of reactivity and structures of palm kernel shell (PKS) biochar during CO_2/H_2O mixture gasification

Palm kernel shell(PKS)biochars with different levels of carbon conversion were initially prepared using a tube furnace,after which the reactivity of each sample was assessed with a thermogravimetric analyzer under a CO_2 atmosphere.The pore structure and carbon ordering of each biochar also examined,employing a surface area analyzer and a Raman spectroscopy.Thermogravimetric results showed that the gasification index R_sof the PKS biochar decreased from 0.0305 min^(-1) at carbon conversion(x)=20% to 0.0278 min^(-1)at x=40%.The expansion of micropores was the dominant process during the pore structure evolution,ad mesopores with sizes ranging from 6 to 20,48 to 50 nm were primarily generated during gasification under a CO_2/H_2O mixture.The proportion of amorphous carbon in the PKS biochar decreased significantly as x increased,suggesting that the proportion of ordered carbon was increased during the CO_2/H_2O mixed gasification.A significantly reduced total reaction time was observed when employing a CO_2/intermittent H_2O process along with an 83.46% reduction in the steam feed,compared with the amount required using a CO_2/H_2O atmosphere.

Analysis of Lateritic Soil Reinforced with Palm Kernel Shells for Use as a Sub-Base Layer for Low-Traffic Roads

In tropical areas,palm oil production generates significant amounts of waste,including palm kernel shells.The use of this waste in the civil engineering sector,presents a very challenging task.In the present study,the production of lateritic soil(A-2 in GTR classification and A-7-6(9)in HRB classification)reinforced with palm kernel shells is considered.In order to improve their performances,these materials are mixed using the Fuller’s parabolic law.Moreover,experimental tests are used to characterize the physical and mechanical geotechnical properties of the lateritic soil.After characterizing the matrix(i.e.,lateritic soil)and the inclusions(i.e.,palm kernel shells)in their natural state,it is found that Avrankou’s lateritic soil has a high level of fine particles(56.6%),high plasticity(PI=21%)and low lift(ICBR=17%);which makes it unusable in the pavement layer.Results also prove that the mixture composed of 39%of lateritic soil volume and 61%of PKS with a CBR index equals to 30 and the mixture composed of 45%of lateritic soil,40%PKS and 15%of lagoon sand with a CBR index equals to 41 can be used as sub-base layer for roads for low and medium traffic,respectively.

Size Variation of Palm Kernel Shells as Replacement of Coarse Aggregate for Lightweight Concrete Production

The utilization of palm kernel shells (PKS) as an alternative to conventional materials for construction is desirable to promote sustainable development. The purpose of this study is to investigate the properties of lightweight concrete produced with different sizes of PKS of 6, 8, 10, 12 mm and mix (consisting of 25% each of the four sizes). RPK sizes were used to replace coarse aggregate in the concrete and cured for 7, 14, 21 and 28 days. The tests performed on the concrete are dry density, compressive strength, flexural strength, EDS and SEM. It was revealed that the densities of the concrete specimens were all less than 2000 kg/m3, which implies that the PKS concrete satisfied the requirement of lightweight concrete for structural application. The compressive strength of the 12 mm PKS concrete specimens at 28-day of curing was 10.2 MPa which was 4% to 15.9% better than the other PKS sizes concrete. The flexural strength of the 12 mm PKS concrete specimens at 28-day of curing was 2.85 MPa which was also 3.2% to 57.07% better than the other PKS sizes concrete. It was also revealed by the SEM analysis that there was a good bond between the palm kernel shells and the mortar. A high calcium-silicate content was found in the concrete which resulted in a Ca/Si ratio of 1.26 and Al/Si ratio of 0.11. The study therefore concludes that size variations of PKS as replacement of coarse aggregate have an influence on the properties of the lightweight concrete and recommends 12 mm PKS for use by construction practitioners for lightweight concrete structural application.

Experimental and Analytical Study of Water Diffusion in Palm Kernel Shell of Cameroon

Moisture diffusion during soaking of palm kernel shell (Elaeis guineensis) aggregate concerning DURA variety of Cameroon was studied. Parameters like percentage of water gain at the saturation point and the effective moisture diffusivity were the main purposes. The knowledge of the behavior of those shells in presence of the liquid during the realization of the composite materials is important. Gravimetric method with discontinuous control of the mass of sample after immersion at the ambient temperature was used. Palm kernel shell aggregate of two origins and two considerable sizes respectively in mm: Sizes ≥ 16 and 12.5 ≤ Sizes < 16 were used. The rate of water absorption was found to be [6.18% and 11.74%] respectively for Tombel PKS and Bafang PKS and moisture diffusivity of [5.19 × 10-8 and 7.90 × 10-9 m2/s] was also determined according to their irregular shapes by fitted soaking data in Becker’s model.

Industrial Elaboration by Extrusion of PVC Tubes Loaded with Micronized Dura Palm Kernel Shell Powder

We present in this work how to use the dura palm kernel shell powders as loads for the elaboration by extrusion of PVC tubes. The transformation of dura palm kernel shells into micronized shell powder as well as its characterization was the subject of recent work. We carried out, the formulations by using the industrial scales of precision, the mixtures of the instrants with an industrial machine of mark HENSHLLE N˚2 MAIN 570762, the routine tests by ATG/DSC then by IRTF, the extrusion of the tubes with an extruder twin-screw with 9 rooms of transformation finally the tests of conformity by the observations and the analyses. We obtained for the formulations the dosage of 0%, 4.01%, 12.54%, 23.03%, 32.01%, 38.01%, 51.02% representing the percentage of hull powder in the mixture, the machine mixing gave perfectly homogeneous powders, the routine tests showed that the hull powder keeps all its properties until the end of the shaping whatever the percentage of hulls contained in the PVC, the extrusion gave tubes for each formulation and the conformity tests gave perfectly round tubes of diameter 90 × 82 mm, a coloration going from white grey at 0% to dark black at 51.02% showing the influence of the carbon black and the color of the shell powder according to its proportion. The infrared of the tubes obtained shows for each formulation a variation of the CH2 and CH bonds and a decrease of the −OH bonds. The thermogravimetric analyses and the differential calorimetric analyses of the tubes of each formulation, show each time that the quantity of shell powders in the mixture influences the PVC tubes obtained. Thus, we obtain a variation of the phase temperatures according to the dosage, giving from 108.72˚C to 76.56˚C for the glass transition temperature and from 494.71˚C to 414.56˚C for the melting temperature, at the DSC and a progressive decrease of the mass following the heat absorption with each time 4 phases instead of 5 for the unloaded PVC tubes at the ATG according to the dosage.

Insight on the Ultrastructure, Physicochemical, Thermal Characteristics and Applications of Palm Kernel Shells

The ultrastructure and physicochemical and thermal properties of Palm Kernel Shells (PKS) in comparison with Coconut Kernel Shells (CKS) were investigated herein. Powder samples were prepared and characterized using Surface Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Chemical and elemental constituents, as well as thermal performance were assessed by Van Soest Method, TEM/EDXA and SEM/EDS techniques. Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) were also performed for thermal characterization. SEM/EDS and TEM/EDXA revealed that most of the PKS and CKS materials are composed of particles with irregular morphology;these are mainly amorphous phases of carbon/oxygen with small amounts of K, Ca and Mg. The DSC data permitted to derive the materials’ thermal transition phases and the relevant characteristic temperatures and physical properties. Thermal Transition phases of PKS observed herein are consistent with the chemical composition obtained and are similar to those of CKS. Nonetheless, TGA/DTG showed that the combustion characteristics of PKS are higher than those of CKS. Taken together, our results reveal that PKS have nanopores and can be efficiently used for 3D printing and membrane filtration applications. Moreover, the chemical constituents found in PKS samples are in agreement with those reported in the literature for material structural applications and thus, present potential use of PKS in these applications.

Effects of Palm Kernel Shell on the Microstructure and Mechanical Properties of Recycled Polyethylene/Palm Kernel Shell Particulate Composites

The effect of palm kernel shell on the microstructure and mechanical properties of recycled polyethylene (RLDPE) reinforced with palm kernel shell particulate composite was evaluated to assess the possibility of using it as a new material for engineering applications. The composites were produced by compounding and compressive moulding technique by varying the Palm kernel shell particle from 5-25vol% with particles size of 150, 300 and 400 μm. The microstructure (SEM/EDS) and the mechanical properties of the composites were investigated. The hardness of the composite increases with increase in palm kernel shell content and the tensile strength of the composite increased to optimum of 5vol%. Scanning electron Microscopy (SEM) of the composites surfaces indicates fairly interfacial interaction between the palm kernel shell particles and the RLDPE matrix. The composites produced with 150 μm particle size have the best properties of the entire grade. Hence this grade can be use for interior applications such as car seat, dash board, and car interior for decorative purposes or other interior parts of automobile where high strength is not considered a critical requirement.

Design of Steam Turbine for Electric Power Production Using Heat Energy from Palm Kernel Shell

The steam turbine is a prime mover that converts kinetic energy in steam into rotational mechanical energy through the impact or reaction of the steam against the blades. The aim of this study is to design a steam turbine for a small scale steam power plant with target of producing electricity. The turbine is driven by the heat energy from palm kernel shells as a renewable energy source obtained at a lower or no cost. The study was concentrated on design of turbine elements and its validation using computer packages. Specifically, the microturbine design was limited to design, modeling, simulation and analysis of the rotor, blades and nozzle under the palm kernel shell as fuel for the micro power plant. In blade design, stress failures, efficiency and blade angle parameters were considered. In casing volume design, the overall heat transfer and mean temperature, and different concepts were applied. The thermal distribution on stator and rotor was considered in order to determine its level of tolerance. The design software packages used for design validation were Solidworks and Comsol Multiphysics for analysis. Simulation results showed that the designed steam turbine can adequately tolerate change in stress/load, torsion/compression, temperature and speeds.

Experimental Investigation of Lime Treated Palm Kernel Shell and Sugarcane Bagasse Ash as Partial Replacement of Coarse Aggregate and Cement Respectively in Concrete

This experimental research is focused on the effect of concrete made by incorporating lime treated Palm Kernel Shell (PKS) & Sugarcane Bagasse Ash (SCBA) as partial replacements of coarse aggregates and Ordinary Portland Cement (OPC) respectively. An experimental analysis for concrete grade 30 with a mix design ratio of 1:1.97:3.71 of cement:fine aggregates:coarse aggregates with a constant water to cement ratio of 0.5, was used. Physical tests such as workability on fresh concrete and water absorption on hardened concrete of each batch were carried out. Mechanical tests like compressive strength and split tensile strength were carried out on hardened concrete cubes (100 mm × 100 mm × 100 mm) and cylinders (100 mm × 200 mm) at 7 and 28 days. The experimental results obtained in this study indicate the possibility of using up 15% of lime treated PKS and 10% of SCBA for production of structural concrete.

Adsorption Isotherm and Kinetic Study of Methane on Palm Kernel Shell-Derived Activated Carbon

Activated carbon(AC)was synthesized from palm kernel shell(PKS)using different activating agents,i.e.,steam,carbon dioxide(CO 2),and CO 2-steam,in order to analyze the impact of acti-vating agents on the pore opening of AC.In this study,AC produced from PKS was found to have great potential as an adsorbent for methane storage.The different molecular diffusivity and reac-tivity of the combination of CO 2 and steam succeeded in producing AC with the highest burn-offof 78.57%,a surface area of 869.82 m 2/g,a total pore volume of 0.47 cm 3/g,and leading to maximum methane gas adsorption capacity of 4.500 mol/kg.All types of ACs exhibited the best fit with the Freundlich isotherm model,with the correlation coefficient(R 2)ranging from 0.997 to 0.999,indicating the formation of multilayer adsorption.In addition,the adsorption kinetic data for all ACs followed the pseudo-first-order model showing that the rate of adsorption was dependent on both the adsorbent and the adsorbate and was governed primarily by physical ad-sorption between the pore surface and methane gas.The results of intraparticle diffusion model indicated that the adsorption of methane was affected by both pore diffusion and exterior layer diffusion due to the different adsorption rates.

Clean utilization of palm kernel shell:sustainable and naturally heteroatom-doped porous activated carbon for lithium-sulfur batteries

Lithium-sulfur batteries(LSBs)have received much concern as emerging high-power energy storage system.Nevertheless,the low conductivity of sulfur and poly sulfide shuttle results in low rate capability and rapid capacity decay,which seriously limit its commercial application.Here,facile,sustainable and cost-effective strategy for preparing heteroatom-doped porous activated carbon(PAC)derived from biomass palm kernel shell(PKS)was developed for high-performance LSB applications.The presence of N,P and S heteroatoms with modification of the surface polarity brings about large amounts of active sites and improved adsorption property compared to those of common carbon materials.The PAC sample possesses desirable specific surface area(SSA)(2760 m2·g-1)as well as pore volume(1.6 cm3·g-1).Besides,the good electrical conductivity of PAC endows the material with excellent rate performance.The PAC-S electrode with a 60%of sulfur loading has a desirable first discharge capacity(1045 mAh·g1,200 mA·g-1)with superb discharge capacity(869.8 mAh·g-1,100 th cycle)and cyclability(312.6 mAh·g-1,800 mA·g-1,1000 th cycle),which can be mainly ascribed to its unique porous properties and the good conductivity of PAC.

Formation mechanism and application potential of carbon dots synthesized from palm kernel shell via microwave assisted method

The present study systematically investigated the influence of synthesis conditions(duration,reaction medium,and doping concentration)and formation mechanism of carbon dots(CDs)derived from low-cost and abundant biomass palm kernel shell(PKS).Surprisingly,the dopant(urea)did not enhance the photoluminescence of CDs as expected,which could be attributed to the low reactivity between the dopant and PKS macromolecules.Variation of synthesis duration from 30 to 120 s clearly indicated the formation mechanism of CDs,involving the stages of dehydration,carbonization,and nucleation.The CDs with the highest photoluminescent intensity and quantum yield was obtained at synthesis duration of 90 s,aligned well with the perfect spherical shape of CDs and the synergistic effects of both surface and carbogenic core conditions.Understanding the formation mechanism could be used to optimize the synthesis of CDs,and hence linked to quantum yield and fluorescent intensity.In terms of application potential,the CDs illuminated well as fluorescent ink and in bacteria cells imaging.The potential of CDs as sensing material has also been proven with the quenching of fluorescence in the presence of metal ions.The linear range for detection of Cu2+ions was 0.1–0.5 mM with a detection limit as low as 0.05 mM.This signifies the potential of CDs fabricated from PKS as a low-cost and easily available material for Cu2+ions detection in aqueous solution.The CDs possessed reasonable photo stability as indicated by its consistent fluorescence level even after exposure to UV radiation for a prolonged period of 180 minutes.Overall,a simple,straightforward,and fast method is developed to synthesis strong blue emissive CDs from green PKS that are potentially suitable for Cu2+ions sensing in real application.

Life cycle analysis of palm kernel shell gasification for supplying heat to an asphalt mixing plant

The Government of the Republic of Indonesia states that the thermal energy for hot-mixed asphalt production shall be supplied by the direct combustion of fossil fuels in the form of diesel oil,natural gas,or fuel gas from coal gasification which may generate GHG emission.Biomasses are able to substitute the fossil fuels through gasification technology.Gasification converts the biomass using limited air into gaseous fuel containing mainly CO and H_(2) that are subsequently combusted to produce heat,carbon dioxide,and water.It is obvious that the CO_(2) is then absorbed by the plants for photosynthesis,main-taining a balanced closed cycle.This study examines the level of global warming potential of this system for supplying heat based on the openLCA v1.9 software.The analysis used a gate-to-gate approach to evaluate scenarios of shell gasification to produce 1 metric tonne of hot-mixed asphalt.The scope covers raw material supply and transportation,palm kernel shell gasification,and products.The evaluation concludes that gasification could potentially reduce CO_(2) emissions.Environmental impact analysis and interpretation of the results using the openLCA database of Traci 2.1 recommend that greater CO_(2) emis-sion reduction is possible using palm kernel shell gasification,not only for supplying heat but also for electricity generation to operate all electrical equipments.

Physicochemical and Thermal Characterization of Dura Palm Kernel Powder as a Load for Polymers: Case of Polyvinyl Chloride

This work presents the physical and thermal characterization of the dura palm kernel powder of Cameroon for their use as fillers for polymers composites. The powders of palm kernel were obtained using a percussion grinder mill with an industrial microniser which allowed obtaining a powder less than 50 μm with an apparent density between 0,505 ≤ ρ ≤ 0,680 g/cm3 at 1.56 of relative humidity. The infrared of the powder of palm kernel shows the presence of phenols groups with a large band around 3341 cm-1, -C-H at 2917.02 cm-1 and -C-O at 1040 cm-1 as the main peaks. The polyvinyl chloride of infrared obtained shows the presence of -C-Cl, -CH2 and CH as the mains peaks. The infrared of 12.5% of palm kernel powder with polyvinyl chloride shows an increase of the CH2 and CH bonds and a decrease of the -OH bonds. Thermogravimetric analysis and differential scanning calorimetric analysis of powders, polyvinyl chloride and mixture showed that the mixing powders are intermediate between the polyvinyl chloride and palm kernel powder. The powder decreased the phase temperatures of the mixture from 98.58℃ to 95℃ for the glass transition temperature and from 515℃ to 459℃ for the crystallization temperature. The thermogravimetric curves of palm kernel powder and polyvinyl chloride have showed that these materials lose their different masses in three different phases, and the one of composite (mixture of polyvinyl chloride with 12.5% of palm kernel powder) in two different phases.

棕榈壳热解失重特性及动力学研究

采用热重-红外联用（TG-FTIR）、裂解-气相色谱/质谱联用（Py-GC/MS）技术和小型固定床装置,考察了棕榈壳的热解失重过程和产物特性,并进一步评价了热解半焦的气化反应性。结果表明：棕榈壳热解失重过程大致分为干燥（25-236℃,3.42%）、主失重（236-400℃,52.31%）和炭化（400-850℃,14.90%）3个阶段,1.5级或2级反应可以较好描述棕榈壳热解反应的主失重过程;升温速率10-30 K/min下,反应表观活化能为67.63-76.47 k J/mol;热解过程主要气体产物的释放量顺序分别为CO2、H2O、CH4和CO;600-850℃下,棕榈壳主要热解产物为液相产物,其质量产率36.8%-50.9%,能量产率41.3%-58.9%,主要组分包括苯酚、乙酸、十八烷酸、十六烷酸、4-烯丙基-2,6-二甲氧基苯酚等物质,其中苯酚GC含量较高（12.56%-15.49%）,这可能主要与原料木质素的含量较高有关;固相产物的质量和能量产率分别为20.6%-26.7%和27.4%-35.0%,其CO2气化反应性相对低于稻秆、木粉等常见生物质。

棕榈壳焦CO_2气化过程中反应性及结构特性研究

850℃下,利用管式炉制备了不同转化率的棕榈壳CO2气化焦,通过热重分析仪研究了气化焦的CO2气化反应性,采用比表面积分析、拉曼光谱、X射线荧光光谱和扫描电镜-能谱等分析手段,考察了气化焦孔隙结构、碳组成、矿物元素含量与分布随转化率的变化。结果表明,在CO2气化过程中,随着转化率的提高,棕榈壳气化焦固定碳的含量逐渐降低,有序化碳的相对含量为0.30～0.33,对气化过程起到一定的抑制作用;灰分含量逐渐增加,但气化反应指数Rs呈现先降低后升高的过程。转化率小于23%时,Rs与气化焦比表面积的变化趋势一致;23%〈转化率〈31%时,Rs基本不变;31%〈转化率〈68%时,比表面积随转化率线性增加,Rs取决于孔隙比表面积、矿物元素催化2个因素的协同作用,当转化率〉56%时,该催化作用变得明显,同时碳的有序化程度开始降低;转化率〉68%时,Rs主要受矿物元素的催化作用控制。

不同粒径棕榈壳的热失重过程及产物特性分析

采用小型固定床与热重分析仪、气相色谱-质谱仪和比表面积分析仪等,考察不同粒径下棕榈壳的热失重过程与产物特性。结果表明：随着粒径的增大（0.950.0 mm）,棕榈壳热解主失重阶段的失重量明显降低,第1个失重速率峰的温度前移29℃,同时峰值增加22.18%/min。600850℃下,棕榈壳热解气体的产率随粒径的增大而增加,但粉状组（≤0.9 mm）的低位热值最高。改变粒径对热解焦油（主要为苯酚和乙酸）的种类影响较小。半焦产率随粒径的增大而增加,但其CO2气化反应性明显下降。

棕榈粕对粉壳蛋鸡生产性能及蛋品质量的影响

试验选用215日龄罗曼粉蛋鸡540只,研究添加不同水平棕榈粕对产蛋性能和蛋品质量的影响。试验共设3个处理,每个处理5个重复,每个重复36只鸡,随机饲喂添加两个水平棕榈粕(3.75%和5%)的日粮和未添加棕榈粕的商品蛋鸡饲料。试验结果经统计分析表明:各处理组在日采食量、产蛋率、平均蛋重、料蛋比、蛋壳强度和哈夫单位等方面差异不明显,说明蛋鸡日粮中添加棕榈粕3.75%和5%,对蛋鸡生产性能和蛋品质量未产生显著影响。

褐煤与棕榈壳微波共热解特性实验研究

在微波加热方式下,采用自行设计的两段式石英反应器考察热解温度和吸波剂的添加对褐煤与棕榈壳共热解特性的影响,利用气相色谱-质谱联用仪和气相色谱仪分别对焦油和热解气体进行分析.结果表明:在褐煤与棕榈壳共热解过程中二者存在明显的协同作用,挥发分产率有明显增加.利用活性炭做吸波剂时,焦油产物有一定的轻质化,且轻气体产物中产生较高含量的CO和H_2.在600℃下,活性炭做吸波剂时,CO和H_2在轻气体中的总产率达到91.98%(体积分数).