Chun-Ping Lin

Modeling solid thermal explosion containment on reactor HNIW and HMX.

2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaaza-isowurtzitane (HNIW), also known as CL-20 and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), are highly energetic materials which have been popular in national defense industries for years. This study established the models of thermal decomposition and thermal explosion hazard for HNIW and HMX. Differential scanning calorimetry (DSC) data were used for parameters determination of the thermokinetic models, and then these models were employed for simulation of thermal explosion in a 437L barrel reactor and a 24 kg cubic box package. Experimental results indicating the best storage conditions to avoid any violent runaway reaction of HNIW and HMX were also discovered. This study also developed an efficient procedure regarding creation of thermokinetics and assessment of thermal hazards of HNIW and HMX that could be applied to ensure safe storage conditions.

Kinetic and safety parameters analysis for 1,1,-di-(tert-butylperoxy)-3,3,5-trimethylcyclohexane in isothermal and non-isothermal conditions.

Over the past 30 years, the field of thermal analysis of organic peroxides has become an important issue in chemical engineering departments, safety departments, and in companies working with polymerization, petrifaction process, and so on. The contributions of thermal analysis to the evaluation and prediction of the runaway reactions have been important for decreasing or preventing a hazard, such as fire or explosion accident. This study was carried out using differential scanning calorimetry (DSC) to evaluate the kinetic and safety parameters in isothermal and non-isothermal conditions, for instance, temperature of no return (T(NR)), self accelerating decomposition temperature (SADT), time to maximum rate (TMR), activation energy (E(a)), frequency factor (A), reaction order (n), and reaction heat (ΔH), in terms of the hazardous material of 1,1,-di-(tert-butylperoxy)-3,3,5-trimethylcyclohexane (TMCH) 88 mass%. On the basis of this study, we demonstrated that TMCH 88 mass% must be well controlled in the manufacturing process due to the unstable structure of O-O, which releases a great quantity of heat, higher than 1300 J/g under decomposition. Results of this study could contribute to the relevant plants adopting TMCH 88mass% in a process, in order to prevent a fire or explosion accident from happening.

Isothermal versus non-isothermal calorimetric technique to evaluate thermokinetic parameters and thermal hazard of tert-butyl peroxy-2-ethyl hexanoate

Liquid organic peroxides have been broadly employed in the process industries such as tert-butyl peroxy-2-ethyl hexanoate (TBPO). This study investigated the thermokinetic parameters of TBPO, a typical liquid organic peroxide, by isothermal kinetic algorithms and non-isothermal kinetic algorithms with thermal activity monitor III, and differential scanning calorimetry, respectively. An attempt has been made to determine the thermokinetic parameters by simulation software, such as exothermic onset temperature (T0), maximum temperature (Tmax), decomposition (∆Hd), activation energy (Ea), self-accelerating decomposition temperature, and isothermal time to maximum rate (TMRiso). A liquid thermal explosion model was established for a reactor containing liquid organic peroxide of interest. From experimental results, liquid organic peroxides’ optimal conditions for avoiding a violent runaway reaction of storage and transportation were created.

Storage lifetime management and thermal hazard assessment of thermally reactive material

This is a novel idea: replacing highly dangerous and complex testing of solid thermally reactive materials through smart technology. We investigated the prediction of the storage lifetime and the thermal impact of thermally reactive material by different thermal analysis models: differential scanning calorimetry (DSC) for non-isothermal tests versus DSC isothermal tests. Two kinds of kinetic models were compared for evaluating appropriate kinetic parameters of thermal decomposition, and then the thermal hazard parameters were estimated by cartridge package simulation, which could result in reliable thermal hazard properties of a thermal reactive material’s thermal decomposition. We also determined the unsafe characteristics of a thermally reactive material stored in a depot under lifetime, so as to prevent runaway reactions that induce incidents by heat attack during storage. We were interested in an effective and smart analysis technology to reduce energy consumption of the dangerous testing. There are also calls for a smart testing technology which is the achieved object here for reducing energy consumption and avoiding runaway reaction disaster of thermally reactive materials.

RDX Kinetic Model Evaluation by Nth Order Kinetic Algorithms and Model Simulations

A kinetic model based on the thermal decomposition of 1,3,5-trinitro-1,3,5-triazmane (RDX) was constructed via differential scanning calorimetry (DSC), well-known kinetic equations, curve-fitting analysis, and simulations of thermal analysis. Our objective was to analyze thermokinetic parameters derived from heating rates used in DSC and compare simulations of thermal decomposition under various kinetic models. Experimental results were strongly dependent on the validity of the kinetic model, which was based on an appropriate mathematical model and a proper method for the evaluation of kinetics. Through six types of kinetic algorithms, a reasonable value of the Ea of the thermal decomposition of RDX was obtained. Finally, this study established a novel green technology for the thermal analysis of reactions and obtained information on the characteristics of thermal decomposition and reaction hazards of RDX.

Prediction of thermal hazard of liquid organic peroxides by non-isothermal and isothermal kinetic model of DSC tests

Liquid organic peroxides (LOPs) have been widely used as initiators of polymerization, hardening, or cross-linking agents. We evaluated a beneficial kinetic model to acquire accurate thermokinetic parameters to help preventing runaway reactions, fires or explosions in the process environment. Differential scanning calorimetry was used to assess the kinetic parameters, such as kinetic model, reaction order, heat of reaction (ΔHd), activation energy (Ea), frequency factor (lnk0), etc. The non-isothermal and isothermal kinetic models were compared to determine the validity of the kinetic model, and then applied to the thermal hazard assessment of commercial package contaminated with LOPs. Simulations of a 0.5-L Dewar vessel and 25-kg commercial package were performed. We focused on the thermal stability of different liquid system properties for LOPs. From the results, the optimal conditions were determined for avoiding violent heat effects that can cause a runaway reaction in storage, transportation, and manufacturing.

Safety management on fire emergency response by VESDA applications at semiconductor plants

To take an advantageous stance in the recent competition of semiconductor industries, companies have made efforts to invest terms of technological advancements. From 1993 to 2006, enormous fire accidents occurred in three national science parks in Taiwan. This research focused on whether the very early smoke detection apparatus (VESDA), could adequately assist the emergency response center (ERC) members to take actions when alarm occurs. Besides, the research also analyzed every VESDA alarm that happened from 2004 to 2006 for the purpose of increasing ERC personnels experience and coordinating ERC with departments of safety management, environmental protection, facility engineering, and equipment sections together to investigate better solutions to related problems.

Degradation of Polylactic Acid by Irradiation

Polylactic acid (PLA) waste has various treatment methods, such as natural decomposition, composting, incineration, and hydrolysis. Degradation of PLA waste by gamma ray and pulsed light irradiation is an efficient, safe and innovative method that also protects the environment. The focus of this study was on the development of an alternative, green technology for solving the PLA waste disposal problem of PLA, rather than using incineration or the landfill method. We used a novel approach to identify the thermal decomposition and heat properties of crystalline poly lactic acid, non-crystalline polylactic acid, and blend polylactic acid. The approach involved the degradation of the materials with gamma ray and pulsed light irradiation followed by thermogravimetric analysis (TGA). We also developed a novel approach to the heat effect, including heat reactivity properties by TGA tests and thermal mass loss simulation for proper application, processing, and waste treatment conditions. The data from this study can be used to improve the design of operation and waste treatment protocols for PLA, which will benefit the environment.

Thermal Stability Determination, Anti-Biodegradation, and Thermal Degradation of Nitrocellulose with Various Nitrogen Content by DSC and FT-IR

This study fully exploited the advantages of the similarities between chitosan and nitrocellulose (NC), their non-toxicity, superior germproof effects, and the characteristic of restraining fungal growth, to prevent NC’s biodegradation. In a comparison between NC’s Ea, the differences among them were dealt with or not with germproof chitosan by differential scanning calorimetry (DSC). We also observed specific functional groups with Fourier transform infrared (FT-IR) spectrometer to characterize the functional group transformation of NC under various thermal conditions.

Compositional Differences of the Winter Culinary-Medicinal Mushroom, Flammulina velutipes (Agaricomycetes), under Three Types of Light Conditions

The focus of this study was to investigate the effect of light on the cultivation and the amounts of bio-active components in Flammulina velutipes. The mushrooms were cultivated under fluorescent tube (T8) grow lights, lightemitting diodes (LEDs), and cold-cathode fluorescent lamps. The biological efficiency of the T8 lights was the highest, at 92%. The crude fat content, crude fiber content, polysaccharide content, and ergosterol content were highest under the LEDs, at 2.9 g/100 g, 7.9 g/100 g, 3.9 g/100 g, and 1.4 mg/g, respectively. Moreover, vitamin D2 (1.9 μg/g) was generated only under light from LEDs. Principal component analysis showed that F. velutipes cultivated under the 3 different lighting conditions showed different profiles for proximate composition, nutritional compounds, and principal fatty acids.