Using Modified Multi-Walled Carbon Nanotubes with Ultrasonic Homogenizer for BTEX Removal from Aqueous Solutions

Background: BTEX refers to a volatile compound with single aromatic ring in petroleum including benzene, toluene, ethyl benzene, and xylenes. Due to its flammability, toxicity and carcinogenicity properties, BTEX has many adverse effects on human health. This study aimed to evaluate the efficiency of multi-walled carbon nanotube (MWCNT) modified with an ultrasonic homogenizer (UH) to remove BTEX from aqueous solutions. Methods: MWCNT was modified in different concentrations, times and intensities. Then, the best condition was selected. After modification based on the design of experiments (DOE), 16 experiments were arranged at 4 levels with 4 factors. Samples required for simulation were built according to the standard methods and then analyzed by gas chromatography mass. Results: The results revealed that the optimum conditions for modified carbon nanotubes were obtained at concentration of 30% sodium hypochlorite, time of 5 seconds, and intensity of 50 dB. The optimum conditions for initial BTEX concentration, MWCNT dose, contact time, and pH were 100 mg/L, 2000 mg/L, 20 min and 7 respectively. Conclusions: The results indicated that carbon nanotubes modified with homogenizer are a simple and effective technique to remove BTEX from the environment

Using Modified Multi-Walled Carbon Nanotubes with Ultrasonic Homogenizer for BTEX Removal from Aqueous Solutions

Background: BTEX refers to a volatile compound with single aromatic ring in petroleum including benzene, toluene, ethyl benzene, and xylenes. Due to its flammability, toxicity and carcinogenicity properties, BTEX has many adverse effects on human health. This study aimed to evaluate the efficiency of multi-walled carbon nanotube (MWCNT) modified with an ultrasonic homogenizer (UH) to remove BTEX from aqueous solutions. Methods: MWCNT was modified in different concentrations, times and intensities. Then, the best condition was selected. After modification based on the design of experiments (DOE), 16 experiments were arranged at 4 levels with 4 factors. Samples required for simulation were built according to the standard methods and then analyzed by gas chromatography mass. Results: The results revealed that the optimum conditions for modified carbon nanotubes were obtained at concentration of 30% sodium hypochlorite, time of 5 seconds, and intensity of 50 dB. The optimum conditions for initial BTEX concentration, MWCNT dose, contact time, and pH were 100 mg/L, 2000 mg/L, 20 min and 7 respectively. Conclusions: The results indicated that carbon nanotubes modified with homogenizer are a simple and effective technique to remove BTEX from the environment

Alternative Disinfection Methods Use to Control of Microbial Quality and Shelf-life of Raw Eaten Vegetables (Case Study)

Background: Fresh-cut vegetables are particularly susceptible to microbial growth and, therefore, the use of an effective sanitizer on this product is great importance. Method: The common vegetable  types obtained from a local wholesale market in Isfahan and washed with different common disinfectants such as edible salt, sodium hypochlorite, electrolyzed water (EW), complex disinfectant, calcium hypochlorite, and dishwashing liquid. Disinfection time and concentration select according to the Official Protocol in Iran. A total of 126 samples including Mint, Savory, parsley, Garden cress, Common Purslane, Chives, Basil, Radish, and mixed vegetables were analyzed for total bacteria, total coliform bacteria, and E. coli. Result: Results demonstrated that calcium hypochlorite has the best efficiency for total coliforms in separate vegetable of parsley, Garden cress, Common Purslane, Chives, Radish, with100% efficacy. For total coliforms BGB (Brilliant Green Broth) test, complex disinfectant and calcium hypochlorite have 100% removal for all of the vegetables. E.coli test result showed in four vegetables not E.coli but for another vegetable except Dishwashing Liquid efficiency was 100%. Among all disinfectants, EW has a high efficiency for mixed vegetables. For Basil disinfected with edible salt and mint washing with complex disinfectant, Eimeria parasite and in savory disinfected with calcium hypochlorite Hook worm parasitic was found. Shelf-life was between 1 to 5 days. Conclusion: Our research suggested that EW has a good effect for total coliforms, fecal coliforms, E.Coli, and helmet eggs removal, also save the vegetable shelf life

Alternative Disinfection Methods Use to Control of Microbial Quality and Shelf-life of Raw Eaten Vegetables (Case Study)

Background: Fresh-cut vegetables are particularly susceptible to microbial growth and, therefore, the use of an effective sanitizer on this product is great importance. Method: The common vegetable  types obtained from a local wholesale market in Isfahan and washed with different common disinfectants such as edible salt, sodium hypochlorite, electrolyzed water (EW), complex disinfectant, calcium hypochlorite, and dishwashing liquid. Disinfection time and concentration select according to the Official Protocol in Iran. A total of 126 samples including Mint, Savory, parsley, Garden cress, Common Purslane, Chives, Basil, Radish, and mixed vegetables were analyzed for total bacteria, total coliform bacteria, and E. coli. Result: Results demonstrated that calcium hypochlorite has the best efficiency for total coliforms in separate vegetable of parsley, Garden cress, Common Purslane, Chives, Radish, with100% efficacy. For total coliforms BGB (Brilliant Green Broth) test, complex disinfectant and calcium hypochlorite have 100% removal for all of the vegetables. E.coli test result showed in four vegetables not E.coli but for another vegetable except Dishwashing Liquid efficiency was 100%. Among all disinfectants, EW has a high efficiency for mixed vegetables. For Basil disinfected with edible salt and mint washing with complex disinfectant, Eimeria parasite and in savory disinfected with calcium hypochlorite Hook worm parasitic was found. Shelf-life was between 1 to 5 days. Conclusion: Our research suggested that EW has a good effect for total coliforms, fecal coliforms, E.Coli, and helmet eggs removal, also save the vegetable shelf life