Effect of Oxidizers on Sulphide Removal from Hair Dissolving Liming Wastewater in Tannery

Liming and unhairing is the conventional operation in the tannery where raw animal skins are treated with sodium sulphide and calcium hydroxide to remove keratin proteins e.g., hair and wool epidermis and to dissolve nonstructural proteins. The hair dissolving liming process discharges wastewater containing soluble sulphide. In acidification, the sulphide in wastewater generates toxic hydrogen sulphide, which has a negative impact on the environment. In this present study, the efficiency of hydrogen peroxide (H2O2) and sodium chlorite (NaClO2) oxidizers are compared to remove sulphide from the hair dissolving liming wastewater. The soluble sulphide in the raw liming wastewater was 3666 mg/L. At optimized dose and pH for H2O2 and NaClO2 soluble sulphide in the solution were 109.2 and 54.6 mg/L, respectively. The sulphide removal efficiency for H2O2and NaClO2 were 97.0% and 98.5%, respectively at an optimum pH (pH 7). Before and after treatment the physicochemical parameters of the liming wastewater were analysed by observing different water quality parameters viz: pH, TDS, EC and salinity. At optimized condition TDS and salinity removal efficiency was 47.2%, 52.3% and 8.1%, 11.2% for H2O2 and NaClO2, respectively. This simple and easy method would be effective for treating hair dissolving liming wastewater in reducing soluble sulphide discharge from the tanneries. Journal of Engineering Science 12(3), 2021, 67-72

Case Report: Local Treatment of a Leishmania tropica Infection in a Syrian Child with a Novel Filmogenic Preparation of Pharmaceutical Sodium Chlorite (LeiProtect®)

Cutaneous leishmaniasis (CL) frequently entails chronic skin lesions that heal only slowly. Until now, the available therapeutic options are very limited. Here, we present a case of a 5½-year-old Syrian refugee with two progressive lower-leg skin ulcers caused by Leishmania tropica. The patient received topical treatment with LeiProtect®, a newly developed, hydroxypropylcellulose-based, filmogenic gel containing nontoxic concentrations of pharmaceutical sodium chlorite. The skin lesions completely healed within 8 weeks and did not relapse during 1 year of follow-up, underlining the efficacy of this novel local therapy of CL.

Sequential Sterilization of Banana (Musa Spp.) Sucker Tip Reducing Microbial Contamination With Highest Establishment Percentage

Sterilization procedure was standardized for grand naine cultivar of banana using various sterilants in combinations and alone. The observations were recorded regularly with respect to presence of fungal, bacteria as well as percentages of culture establishment. Results indicated that a treatment combination No. 3 [Lactic acid (0.15 %) + Tween-20 (0.1 %) + 0.8 % Commercial bleach (30 Min.) followed by Sodium chlorite (0.3 %) (20 min)] gave the highest percentage of aseptic culture establishment in vitro condition. The present study also showed that, single step aseptic inoculation was unable to control endophytic contaminants while sequential treatments were good enough to reduce microbial load as well as increase culture survival. Bangladesh J. Bot. 50(4): 1151-1158, 2021 (December)

Intracluster Sulphur Dioxide Oxidation by Sodium Chlorite Anions: A Mass Spectrometric Study

The reactivity of [NaL·ClO2]− cluster anions (L = ClOx−; x = 0–3) with sulphur dioxide has been investigated in the gas phase by ion–molecule reaction experiments (IMR) performed in an in-house modified Ion Trap mass spectrometer (IT-MS). The kinetic analysis revealed that SO2 is efficiently oxidised by oxygen-atom (OAT), oxygen-ion (OIT) and double oxygen transfer (DOT) reactions. The main difference from the previously investigated free reactive ClO2− is the occurrence of intracluster OIT and DOT processes, which are mediated by the different ligands of the chlorite anion. This gas-phase study highlights the importance of studying the intrinsic properties of simple reacting species, with the aim of elucidating the elementary steps of complex processes occurring in solution, such as the oxidation of sulphur dioxide.

CARBOXYMETHYL CELLULOSE SYNTHESIS FROM TREATED OIL PALM EMPTY FRUIT BUNCH USING IONIC LIQUID AND HYDROGEN PEROXIDE

The synthesis of carboxymethyl cellulose (CMC) generally uses isolated crude cellulose with alkaline or acid pretreatment followed by bleaching with sodium chlorite. In this study, the simple [BMIM][Cl] ionic liquid was used as a solvent in the pretreatment process before conduct the bleaching process with hydrogen peroxide (H2O2) to isolate cellulose from empty fruit bunch (EFB) for further synthesis of CMC. The isolated crude EFB cellulose obtained was converted to CMC by adding 30 wt.% NaOH and various concentrations of sodium monochloroacetic acid (SMCA) at 55 °C for 3 h. The effects of SMCA concentration on the degree of substitution (DS) and CMC yield were investigated. The physicochemical properties of the CMC products were characterized using proton nuclear magnetic resonance, scanning electron microscope-energy dispersive spectrometry, X-ray diffraction, and thermogravimetric analysis. Based on the results, CMC was demonstrated to be synthesized using ionic liquid pretreatment with H2O2 bleaching. Carboxymethyl cellulose synthesized in this study showed a high DS of 0.82. The CMC synthesized from EFB cellulose through ionic liquid pretreatment presented good chemical and physical properties as that reported in other studies.

PROTEOMIC STUDIES IN THE SYMBIOTIC ASSOCIATIONS BETWEEN ARBUSCULAR MYCORRHIZAL FUNGI Funneliformis mosseae WITH MELON (Cucumis melo L.) UNDER SALT CONDITIONS

Arbuscular mycorrhizal fungi (AMF) that can cause mutualism with higher plants. Some studies showed that the symbiosis of AMF will increase nutrients absorption, the capacity of anti-stress (e.g. drought, salt and disease) by melon (Cucumis melo L.). This study evaluated the roles of proteins on salt-tolerance mechanism after melon was symbiotic with AMF (Funneliformis mosseae). The melons were cultivated in the hydroponic solution containing 0 M, 0.042 M or 0.084 M NaCl for inoculated AMF and non-AMF inoculated seedlings. Root apice of AMF seedling after treating with different NaCl concentrations that were chosen for the estimation of proteins. The results showed that 12 proteins were significantly different after treating with different sodium chlorite (NaCl) concentrations, with proteins that four upregulated and eight downregulated. The tolerance of NaCl stress by root of melon that was inoculated by AMF were attributable to cellular activities involved in carbohydrate metabolism, energy metabolism, production of organic acid, relief of salt injury, which may be critical for promotion of nutrients absorption, anti-stress. This study can offer an important clue to advanced genomic exploration for the inoculation of AMF on different plants.

Effect of Absorbents on NOx Removal through Polyvinylidene Fluoride (PVDF) Hollow Fiber Membrane Modules

NOx (NO and NO2) are air toxins that endanger life and represent a hazard to the environment, such as photochemical smog, global warming, acid rain, ozone depletion, and the occurrence of respiratory infections. Some technological strategies to diminish NOx emissions to meet regulations depend on two techniques: the dry process and the wet process. This study applies polyvinylidene fluoride (PVDF) hollow fiber membrane modules as a medium to remove NOx from solutions containing several absorbents such as hydrogen peroxide and nitric acid (H2O2-HNO3) solutions, sodium chlorite and sodium hydroxide (NaClO2-NaOH) solutions, and sodium chlorate and sodium hydroxide (NaClO3-NaOH) solutions. The experimental results showed that the oxidant’s strength influences NOx removal efficiency, where the absorbent solutions containing hydrogen peroxide had the highest removal efficiency as hydrogen peroxide is the most potent oxidant, followed by sodium chlorite and sodium chlorate. The three pairs of absorbents also gave a high NOx removal efficiency (above 90%), which means that all the absorbents used in the study are very potential to be used to diminish NOx via the wet process. NOx removal efficiency at the same feed gas flow rate increased as the number of fiber and absorbent concentrations is increased. However, NOx removal efficiency is reduced as the feed gas flow rate is increased at the same membrane module and absorbent concentration.