Fine Chemical Engineering

Efficiently Controlled Callosobruchus maculatus (F.) (Fam. Bruchidae) by Ultraviolet Ray or Microwave Energy in Conjugation with Pirimiphos-Methyl

Tue, 23 Apr 2024 00:00:00 +0800

This study aimed to explore novel approaches for effectively managing Callosobruchus maculatus while ensuring minimal impact on human health and the environment. The investigation involved exposing the insects to ultraviolet rays (254 nm) for 24 hours, which did not directly cause mortality in adult C. maculatus but led to a significant reduction in their progeny by 10%. The reduction in progeny further increased when insects were pre-exposed to a sublethal dose of actellic at LC₂₅, resulting in a reduction of 39%. Additionally, ultraviolet rays exhibited a significant ovicidal effect, with hatchability reduced to 26% compared to 73% in the control group. Microwave exposure at a low energy level for 4-6 minutes demonstrated a significant acute lethal effect, reduced progeny, and ovicidal action. Combining microwaves with actellic at LC₂₅ slightly enhanced the lethal effect. In conclusion, this study unveils promising strategies for the effective management of Callosobruchus maculatus, highlighting the potential of ultraviolet rays and microwave energy, either alone or in combination with actellic, while emphasizing the importance of minimizing adverse impacts on both human health and the environment.

Pyrolytic Conversion of Waste High-Density Polyethylene to Wax: Temperature Optimization and Characterization of Wax

Achyut Kumar Panda, Pabitra Mohan Mahapatra — Thu, 25 Apr 2024 00:00:00 +0800

The formation of wax from waste high-density polyethylene by thermal decomposition through pyrolysis is examined in this work. To get wax from waste high-density polyethylene, the thermal cracking reaction is run in a semi-batch pyrolysis reactor at 550 °C, 600 °C, and 650 °C. The yield percentage, melting point, specific gravity, and penetration degree of wax varied depending on the temperature. At 600 °C, waste high-density polyethylene yielded the highest wax output (87.25%) with a 0.7768 specific gravity, a 59 °C melting point, and an 81.8 mm penetration degree. The fourier transform infrared spectroscopy (FTIR) analysis concluded the presence of aliphatic hydrocarbon compounds (alkane, alkene, alcohol, and cycloalkane), which is also confirmed by gas chromatography-mass spectrometry (GC-MS) analysis. The innovation in this study lies in the systematic exploration and optimization of temperature conditions for wax production from waste high-density polyethylene (HDPE) bottles.

Sustainable Natural Dyes for Textile Use from Food Industry By-Products: A Review

Noureddine Baaka, Manel Ben Ticha, Wafa Haddar, Nizar Meksi, Hatem Dhaouadi — Tue, 23 Apr 2024 00:00:00 +0800

The valorization of food industry by-products has become very trendy in recent years, several researchers valorized these wastes as sustainable natural colorants for various applications. In this review, the valorization of these by-products in literature as natural dyes in textile application is investigated. Indeed, the history of natural dyes is presented, followed by a study of the advantages and disadvantages of these dyes. Finally, the most significant food industry by-products used as sources of natural dyes for textile applications are listed, along with detailed explanations of their dyeing applications on textile fibers. A special interest is given to natural dyes extracted from food industries wastes of winemaking, olive oil, tomato processing, red pepper by-products and dates paste processing. The majority of studies have demonstrated the strength and superior dyeability of textiles dyed with these waste materials. There have also been assertions that certain fragments have light- and antibacterial-blocking properties.

Disinfection of Water by Chlorine, Peracetic Acid, Ultraviolet and Solar Radiations: A Review

Tue, 16 Apr 2024 00:00:00 +0800

Disinfection is an essential step during water treatment to ensure the microbiological safety of water for human consumption, and over time, it has been improved and better understood. In this context, this review provides a compilation of information, new insights, and perspectives on the main microorganisms present in supply water, their basic structures, and mechanisms of disinfection via chlorine, peracetic acid (PAA), ultraviolet (UV) radiation and solar disinfection (SODIS). Chlorine is the most common chemical disinfectant, however, there is the formation of toxic by-products, which has stimulated the use of non-chlorinated disinfection methods, such as PAA, UV and SODIS. The main advantages of PAA reported in the literature are its high disinfecting power, the non-formation of toxic/carcinogenic by-products, its ability to generate radicals, such as CH₃C(O)O^●, HO^● and HOO^● with or without the use of electromagnetic radiation or thermal energy. The generation of radicals is one of the most used mechanisms to explain the oxidation process during disinfection, which, also prompted studies to use radiation for catalyzing the formation of these radicals. Consequently, physical disinfection processes, such as UV irradiation and SODIS have received significant attention because, in addition to having the ability to damage the RNA (Ribonucleic Acid) and DNA (Deoxyribonucleic Acid) of microorganisms causing their inactivation, these processes also promote the formation of radicals through reactive species that are ubiquitous in natural water. Therefore, the review will be important for studies focused on the process of water disinfection by advanced oxidized processes, especially those that use PAA combined with UV or SODIS.