No abstract

Biodiesel production from vegetable oil produces glycerol as by-product with the amount of about 10 wt% of its product. This excessive amount of glycerol needs to be converted into the higher valuable product. One of the prospective glycerol's derivatives is triacetin, a good bio-additive as antiknocking agent. In this work the synthesis of triacetin from glycerol and acetic acid using sulfuric acid catalyst has been performed in batch reactor and reactive distillation continuous process. Triacetin was synthesized using batch reactor to give 96.30% of glycerol conversion. Reactive distillation can be used as a place of reaction and purification products in one place. Reactive distillation can separate water and acetic acid to the reaction of distillate product around 75% of the main product of bottom results. The production using continuous reactive distillation resulted in glycerol conversion of 98.51%.

Hydrogel based on kappa carrageenan extracted from Kappaphycus alvarezii was synthesized by film immersion in glutaraldehyde solution (GA 4% w/w) as crosslinker for 2 min and then followed by thermal curing at 110 ^oC for 25 min. The obtained crosslinked films were washed using ethanol to remove the unreacted crosslinker and finally dried to constant weight. The aim of this research was to investigate the effect of carrageenan recovery method on the prepared hydrogel properties. The method of carrageenan extraction strongly determined the swelling properties of crosslinked carrageenan. Hydrogel obtained from alkali treated carrageenan showed higher swelling ability compared to hydrogel from nonalkali treated carrageenan. Hydrogel from alkali treated carrageenan showed the ability of sensitive to pH media. Swelling degree of alkali treated carrageenan based hydrogels increased by increasing pH solution from about 5 g/g for neutral pH to 20 g/g for pH~13.

Analysis of thermal decomposition and pyrolisis reaction kinetics of Spirulina platensis residue (SPR) was performed using Thermogravimetric Analyzer. Thermal decomposition was conducted with the heating rate of 10, 20, 30, 40 and 50oC/min from 30 to 1000oC. Thermogravimetric (TG), Differential Thermal Gravimetric (DTG), and Differential Thermal Analysis (DTA) curves were then obtained. Each of the curves was divided into 3 stages. In Stage I, water vapor was released in endothermic condition. Pyrolysis occurred in exothermic condition in Stage II, which was divided into two zones according to the weight loss rate, namely zone 1 and zone 2. It was found that gasification occurred in Stage III in endothermic condition. The heat requirement and heat release on thermal decomposition of SPR are described by DTA curve, where 3 peaks were obtained for heating rate 10, 20 and 30°C/min and 2 peaks for 40 and 50°C/min, all peaks present in Zone 2. As for the DTG curve, 2 peaks were obtained in Zone 1 for similar heating rates variation. On the other hand, thermal decomposition of proteins and carbohydrates is indicated by the presence of peaks on the DTG curve, where lignin decomposition do not occur due to the low lipid content of SPR (0.01wt%). The experiment results and calculations using one-step global model successfully showed that the activation energy (Ea) for the heating rate of 10, 20, 30, 40 and 50oC/min for zone 1 were 35.455, 41.102, 45.702, 47.892 and 47.562 KJ/mol, respectively, and for zone 2 were 0.0001428, 0.0001240, 0.0000179, 0.0000100 and 0.0000096 KJ/mol, respectively.Keywords: Spirulina platensis residue (SPR), Pyrolysis, Thermal decomposition, Peak, Activation energy.Article History: Received June 15th 2017; Received in revised form August 12th 2017; Accepted August 20th 2017; Available onlineHow to Cite This Article: Jamilatun, S., Budhijanto, Rochmadi, and Budiman, A. (2017) Thermal Decomposition and Kinetic Studies of Pyrolysis of Spirulina platensis Residue, International Journal of Renewable Energy Development 6(3), 193-201.https://doi.org/10.14710/ijred.6.3.193-201

Spirulina platensis microalgae is one of the feedstocks used in the production of the third generation of biofuel. The extraction of its lipid for biodiesel leaves behind a residue, which can be treated by pyrolysis to create certain other value-added products. This paper discusses the effects of Spirulina platensis residue (SPR) with respect to grain size (0.105, 0.149 and 0.177 mm), temperature (300 to 600°C) and amount of catalyst (0, 10, 20 and 40 wt.%) on the characteristics of products (bio-oil, water phase, char and gas) obtained from pyrolysis in a fixedbed reactor. The results of the study show that the higher the pyrolysis temperature, the higher the conversion. For the bio-oil product, the optimum temperature is 500°C, which produces a peak yield of 35.99 wt.%. The larger the grain size, the lower the bio-oil yield, gas water and gas, for all of the tested temperatures (300-600°C). The amount of catalyst and the pyrolysis temperature greatly influence the quality of bio-oil products, grouping them into the fractions of LPG (C ≤ 4), gasoline (C5-C11), biodiesel (C12-C18) and heavy naphtha (C ≥ 19). The tendency for LPG-Gasoline formation at optimum conditions, considering the use of a 10 wt.% catalyst at a temperature of 400-500°C, was reported.

Abstract. Due to its specific micropore structure, carbon molecular sieve (CMS) can provide more selective properties than conventional activated carbon in adsorbing molecule from a gaseous mixture. In this research, preparation of CMS for CO2/CH4 separation has been developed by pyrolysis of specially synthesized polymeric resins as the precursor. This research was particularly focused on the development of precursor for the control of carbon microporosity to enhance the sieving properties. Precursor was synthesized through polymerization reaction of phenol with formaldehyde and p-tertbutyl phenol using acid catalyst in a batch reactor. Pyrolysis of the polymeric precursors was carried out in a retort at 450-850 °C in flowing N2 inert gas at flow rate of 100 mL/h for 1.5 hours. The resulting micropore size and surface area of the carbon were characterized using N2-sorption analysis, whereas the carbon surface morphologies were observed using SEM. The carbons were further characterized for their uptake capacity and kinetic selectivity toward CO2 and CH4 gases. The results show that the porous carbon has suitable characteristic as sieving material for CO2/CH4 separation. In this work, CMS with kinetic selectivity (DCO2/DCH4) as high as 8, was produced.

Glycerol as byproduct of biodiesel production is a very promising low-cost feedstock for producing a wide variety of special and fine chemicals. This great amount of glycerol needs to be converted into higher valuable products. One of glycerol's derivatives potential is triacetin, a good bio-additive as anti-knocking agent. In previous work triacetin synthesis from glycerol and acetic acid using sulfuric acid catalyst has been conducted in batch and continuous process. In this work, triacetin was synthesized using reactive distillation. The continuous process has 98.50% of glycerol conversion with 8.98% of triacetin selectivity.

One of the most important aspects in the catalytic cracking of bio-oil is understanding the kinetics of the process.The aim of this paper was to study the kinetics of bio-oil cracking with a silica-alumina catalyst using a continuous fixed-bed reactor. The reaction was studied over the temperature range of 450 to 600 °C with a catalyst bed length of 1 to 4 cm. Three models, Models 1, 2, and 3, were proposed to represent the catalytic cracking kinetics of bio-oil. Model 1 was based on the cracking of bio-oil into the products, while Models 2 and 3 were based on the threeand four-lump models, respectively. The results showed that the rate constants of the catalytic cracking of bio-oil increased with an increasing temperature. The reaction rate constants of the catalytic cracking of biooil using Model 1 ranged from 0.221 to 0.416 cm 3 /g cat·min with an activation energy of 22.3 kJ/mol. It was found that the reaction rate constants from Model 2 can be employed to describe the cracking phenomenon of bio-oil, liquid hydrocarbons, and gas and coke, whereas Model 3 can illustrate the kinetics of bio-oil, kerosene, gasoline, and gas and coke cracking.