Investigation of the decomposition reaction and dust explosion characteristics of crystalline benzoyl peroxides

Thermal stability and oxidation characteristics of α-pinene, β-pinene and α-pinene/β-pinene mixture

Turpentine is a renewable resource, has good combustion performance, and is considered to be a fuel or promising additive to diesel fuel. This is very important for the investigation of thermal stability and energy oxidation characteristics, because evaluation of energy or fuel quality assurance and use safety are necessary. The main components of turpentine are α-pinene and β-pinene, which have unsaturated double bonds and high chemical activity. By investigating their thermal stability and oxidation reaction characteristics, we know the chemical thermal properties and thermal explosion hazard of turpentine. In this present study, the thermal stability and oxidation characteristics of α-pinene, β-pinene and α-pinene/β-pinene mixture were investigated using a high sensitivity accelerating rate calorimeter (ARC) and C80 calorimeter. The important parameters of oxidation reaction and thermal stability were obtained from the temperature, pressure and exothermic behavior in chemical reaction. The results show that α-pinene and β-pinene are thermally stable without chemical reaction under a nitrogen atmosphere even when the temperature reaches 473 K. The initial exothermic temperature of the two pinenes and their mixture is 333–338 K, and the heat release (−ΔH) of their oxidation is 2745–2973 J g⁻¹. The oxidation activation energy (E_a) of α-pinene, β-pinene and α-pinene/β-pinene mixture is 116.25 kJ mol⁻¹, 121.85 kJ mol⁻¹, and 115.95 kJ mol⁻¹, respectively. There are three steps in the oxidation of pinenes: the first is the induction period of the oxidation reaction; the second is the main oxidation stage, and the pressure is reduced; the third is thermal decomposition to produce gas.

Turpentine is a renewable resource, has good combustion performance, and is considered to be a fuel or promising additive to diesel fuel.

Thermal hazards of benzoyl peroxide and its derived process products through theoretical thermodynamics assessment and different calorimetric technologies

Benzoyl peroxide (BPO) is one of the primary OPs used as an initiator, curing agent, or medicine. Some of the plastic processes use BPO without air for maintaining the efficiency of the entire reaction. However, there have been numerous accidents involving BPO in petrochemical plants, especially those related to fire and explosion, that are due to its unstable thermal properties and peroxy bond (OO). BPO can be identified as a typical substance with autocatalytic reaction characteristics. Therefore, the related processes and their products are critical to prevent these kinds of chemical contingencies. This research was based on two types of instruments (nonisothermal and isothermal calorimetry), and theoretical methods to further determine the thermal hazard level. From the experimental results for BPO and BPO mixed with its by-products, the heat of decomposition was much higher (from 800 to 1235 J/g), the time to maximum rate under isothermal conditions was much shorter (from 99.1 to 17.4 h at 75.0 °C), and the apparent activation energy was much lower (from 118 to 91 kJ/mol) after BPO was mixed with its by-products. Therefore, the hazard level of BPO mixed with its by-products from the reaction process was much higher than that of pure BPO.

Skin delivery aspects of benzoyl peroxide-loaded solid lipid nanoparticles for acne treatment

Background: Benzoyl peroxide (BPO) has been a mainstay of topical acne treatment for years. However, is frequently accompanied by cutaneous irritation and erythema. To reduce these side effects many novel drug delivery systems have been developed in the past, of which solid lipid nanoparticles (SLN) demonstrate clear dominance. Hence, we developed a facile method to prepare stable SLN of BPO and evaluated their anti-bacterial activity. Results: BPO-SLN optimized using 23 full factorial design provided high occlusion factor, low permeation rate, increased drug deposition, reduced skin irritation and strong anti-bacterial activity in contrast with marketed product. Conclusion: Desired goals were achieved by factorial design approach in shortest possible time with minimum number of experiments. The developed BPO-SLN system provided controlled drug release, thereby reducing the well-known side effects.

Increase in the ozone decay time in acidic ozone water and its effects on sterilization of biological warfare agents

The sterilization properties of ozone in acidic water are investigated in this study. Acidification of water increases the ozone decay time by several times compared to the decay time in neutral water, thereby enhancing the sterilization strength of ozone in acidic water. A simple analytical model involving the viable microbial counts after contact with acidic ozone water was derived, and a sterilization experiment was conducted on bacterial cells using the acidic ozone water. The acidic ozone water was found to kill very effectively endospores of Bacillus atrophaeus ATCC 9372, thereby demonstrating the potential for disinfection of a large surface area in a very short time and for reinstating the contaminated environment as free from toxic biological agents.