• Energy Research

Microwave pyrolysis is a potential for producing alternative fuel from biomass, such as palm kernel shell (PKS). However, the resulting microwave pyrolytic oil (bio-oil) was highly acidic and has low calorific value and therefore must undergo additional process to improve the physicochemical properties. In this study, attempt was made to improve the pH and calorific value of bio-oil produced from PKS via esterification process. The effect of esterification with ethanol in the presence of sulphuric acid as a catalyst on selected biodiesel qualities was also investigated. The esterification process has successfully improved the pH value from 3.37 to 5.09–5.12 and the calorific value was increased from 27.19 to 34.78–41.52 MJ/kg. Conclusively, the EO has comparatively better properties in terms of its smell, pH, calorific value, and absence of environmentally undesirable compounds. However, future works should include ASTM 6751 specifications tests for biodiesel to evaluate the bio-oil’s suitability for commercial use.

Calcium based catalysts have been studied as promising heterogeneous catalysts for production of methyl esters via transesterification; however a few were explored on catalyst synthesis with high surface area, less particle size, and Ca leaching analysis. In this work, an active Razor shell CaO with crystalline size of 87.2 nm, SBET of 92.63 m2/g, pore diameters of 37.311 nm, and pore volume of 0.613 cc/g was synthesized by a green technique “calcination-hydro aeration-dehydration.” Spectrographic techniques TGA/DTA, FTIR, SEM, XRD, BET&BJH, and PSA were employed for characterization and surface morphology of CaO. Two-step transesterification of Jatropha curcas oil was performed to evaluate CaO catalytic activity. A five-factor-five-level, two-block, half factorial, central composite design based response surface method was employed for experimental analysis and optimization of Jatropha methyl ester (JME) yield. The regression model adequacy ascertained thru coefficient of determination (R2: 95.81%). A JME yield of 98.80% was noted at C (3.10 wt.%), M (54.24 mol./mol.%), T (127.87 min), H (51.31°C), and R (612 rpm). The amount of Ca leached to JME during 1st and 4th reuse cycles was 1.43 ppm ± 0.11 and 4.25 ppm ± 0.21, respectively. Higher leaching of Ca, 6.67 ppm ± 1.09, was found from the 5th reuse cycle due to higher dispersion of Ca2+; consequently JME yield reduces to 76.40%. The JME fuel properties were studied according to biodiesel standards EN 14214 and comply to use as green biodiesel.

The catalytic potential of calcium oxide synthesized from mud clam shell as a heterogeneous catalyst for biodiesel production was studied. The mud clam shell calcium oxide was characterized using particle size analyzer, Fourier transform infrared spectroscopy, scanning electron microscopy, and BET gas sorption analyzer. The catalyst performance of mud clam shell calcium oxide was studied in the transesterification of castor oil as biodiesel. Catalyst characterization and transesterification study results of synthesized catalyst proved the efficiency of the natural derived catalyst for biodiesel production. A highest biodiesel yield of 96.7% was obtained at optimal parameters such as 1 : 14 oil-to-methanol molar ratio, 3% w/w catalyst concentration, 60°C reaction temperature, and 2-hour reaction time. Catalyst reusability test shows that the synthesized calcium oxide from mud clam shell is reusable up to 5 times.

Heat exchangers are important equipment for the process of placing heat. The most widely used type of heat exchanger is shell and tube. This type is widely used because of its simple and easy design. Design of shell and tube heat exchangers is done by the side or shell variations to get the desired performance. Therefore, research is conducted to study the effect of tube thickness on heat transfer, pressure drop, and stress that occurs in the shell and tube heat exchanger so that the optimal tube thickness is obtained. In this research, the activities carried out are the design of heat exchangers for the production of oxygen with a capacity of 30 tons/day. The standard used in this study is the 9th edition heat exchanger design guidance document compiled by the Tubular Exchanger Manufacturer Association (TEMA). Analysis of the tube thickness effect on heat transfer, pressure drop, and stress was carried out using the SimScale platform. The effect of variations in tube thickness on heat transfer is that the thicker the tube, the lower the heat transfer effectiveness. The highest value of the heat exchanger effectiveness is 0.969 at the tube thickness variation of 0.5 mm. The lowest value of the heat exchanger effectiveness is 0.931 at the tube thickness variation of 1.5 mm. The effect of variations in tube thickness on pressure drop is that the thicker the tube, the higher the pressure drop. The highest value of pressure drop is in the variation in tube thickness of 1.5 mm, 321 Pa. The lowest value of drop pressure is in the variation of 0.5 mm tube thickness, which is 203 Pa. The thickness of the tube also increases the maximum stress on the components of the shell, head, tubesheet, baffle, and saddle, but the value is fluctuating

Les catalyseurs hétérogènes sont souvent utilisés dans leur ensemble pour produire du biodiesel à partir d'huiles brutes végétales non comestibles telles que l'huile de Jatropha curcas (JCO). Dans cette étude, un catalyseur de CaO hétérogène actif a été synthétisé à partir d'un coquillage de biodiversité tropicale Anadara granosa (A.granosa). L'efficacité catalytique de A.granosa CaO a été étudiée dans la transestérification de JCO sous forme de biodiesel. Le catalyseur A.granosa CaO a été synthétisé en utilisant le protocole « Calcination – hydratation – déshydratation ». La caractérisation spectrale du catalyseur a été étudiée en utilisant des techniques spectrographiques FT-IR, SEM, BET et BJH. La conception expérimentale a été exécutée avec quatre paramètres de réaction qui comprennent la concentration du catalyseur (CC), le taux de méthanol (MR), le temps de transestérification (TT) et la température de réaction (RT). Les réactions de transestérification de JCO ainsi que l'impact des paramètres de réaction sur le rendement en biodiesel de Jatropha (JBY) ont été analysés. La suffisance des résultats expérimentaux était conforme grâce à des tests de validation séquentiels, en conséquence, une moyenne de 96,2% JMY a été notée dans des conditions paramétriques optimales, CC de 3wt. %, TT de 120 min, MR de 5 mol. et RT de 60ºC à une vitesse d'agitation constante de 300 tr/min. Une JMY moyenne de 87,6 % a été obtenue à partir du catalyseur A.granosa CaO lors de leurs études de recyclage et de réutilisation jusqu'au troisième cycle de réutilisation. Los catalizadores heterogéneos se utilizan a menudo en general para producir biodiésel a partir de aceites crudos vegetales no comestibles, como el aceite de Jatropha curcas (JCO). En este estudio, se sintetizó un catalizador de CaO heterogéneo activo a partir de conchas marinas de biodiversidad tropical Anadara granosa (A.granosa). Se investigó la eficiencia catalítica de A.granosa CaO en la transesterificación de JCO como biodiesel. El catalizador de CaO de A.granosa se sintetizó utilizando el protocolo 'Calcinación – hidratación – deshidratación'. La caracterización espectral del catalizador se investigó empleando técnicas espectrográficas FT-IR, SEM, BET y BJH. El diseño experimental se ejecutó con cuatro parámetros de reacción que incluyen concentración de catalizador (CC), relación de metanol (MR), tiempo de transesterificación (TT) y temperatura de reacción (RT). Se analizaron las reacciones de transesterificación de JCO, así como el impacto de los parámetros de reacción en el rendimiento de biodiésel de Jatropha (JBY). La suficiencia de los resultados experimentales se conformó a través de pruebas de validación secuencial, como resultado, se observó un promedio de 96.2% de JMY en condiciones paramétricas óptimas, CC de 3wt. %, TT de 120 min, MR de 5 mol. y RT de 60ºC a una velocidad de agitación constante de 300rpm. Se obtuvo un JMY medio del 87,6% del catalizador de Cao de A.granosa durante sus estudios de reciclaje y reutilización hasta el tercer ciclo de reutilización. Heterogeneous catalysts are often used at large to produce biodiesel from non-edible vegetable crude oils such as Jatropha curcas oil (JCO). In this study, an active heterogeneous CaO catalyst was synthesized from a tropical biodiversity seashells Anadara granosa (A.granosa). The catalytic efficiency of A.granosa CaO was investigated in transesterification of JCO as biodiesel. The A.granosa CaO catalyst was synthesized using 'Calcination – hydration – dehydration' protocol. The spectral characterization of the catalyst were investigated by employing FT-IR, SEM, BET and BJH spectrographic techniques. The experimental design was executed with four reaction parameters that include catalyst concentration (CC), methanol ratio (MR), transesterification time (TT) and reaction temperature (RT). The JCO transesterification reactions as well as impact of reaction parameters on the Jatropha biodiesel yield (JBY) were analyzed. The sufficiency of the experimental results conformed through sequential validation tests, as a result, an average of 96.2% JMY was noted at optimal parametric conditions, CC of 3wt. %, TT of 120 min, MR of 5 mol. and RT of 60ºC at a constant agitation speed of 300rpm. An average JMY of 87.6% was resulted from the A.granosa CaO catalyst during their recycling and reuse studies up to third reuse cycle. غالبًا ما تستخدم المحفزات غير المتجانسة بشكل عام لإنتاج الديزل الحيوي من الزيوت الخام النباتية غير الصالحة للأكل مثل زيت جاتروفا كركاس (JCO). في هذه الدراسة، تم تصنيع محفز CaO غير متجانس نشط من أصداف البحر الاستوائية للتنوع البيولوجي Anadara granosa (A.granosa). تم التحقيق في الكفاءة التحفيزية لـ A.granosa CaO في تحويل JCO كديزل حيوي. تم تصنيع محفز A.granosa CaO باستخدام بروتوكول "التكليس – الترطيب – التجفيف". تم التحقيق في التوصيف الطيفي للمحفز من خلال استخدام تقنيات FT - IR و SEM و BET و BJH الطيفية. تم تنفيذ التصميم التجريبي بأربعة معلمات تفاعل تشمل تركيز المحفز (CC) ونسبة الميثانول (MR) وزمن التحويل (TT) ودرجة حرارة التفاعل (RT). تم تحليل تفاعلات التحويل JCO بالإضافة إلى تأثير معلمات التفاعل على محصول الديزل الحيوي Jatropha (JBY). تمت مطابقة كفاية النتائج التجريبية من خلال اختبارات التحقق المتسلسلة، ونتيجة لذلك، لوحظ متوسط 96.2 ٪ JMY في الظروف البارامترية المثلى، CC من 3wt. ٪، TT من 120 دقيقة، MR من 5 مول. و RT من 60 درجة مئوية عند سرعة تحريك ثابتة تبلغ 300 دورة في الدقيقة. نتج متوسط JMY بنسبة 87.6 ٪ من محفز A.granosa CaO أثناء دراسات إعادة التدوير وإعادة الاستخدام حتى دورة إعادة الاستخدام الثالثة.