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Critical Cleaning of Advanced Lubricants from Surfaces
Published in Leslie R. Rudnick, Synthetics, Mineral Oils, and Bio-Based Lubricants, 2020
Ronald L. Shubkin, Barbara F. Kanegsberg, Ed Kanegsberg
The solvents are n-propyl bromide (nPB), 1,1,1-trichloroethane (1,1,1-TCA), trichloroethylene (Tric), perchloroethylene (Perc) and methylene chloride (MeCl2). The four lubricants are a mineral oil, a polyol ester, a mineral-oil-based grease, and a silicone oil. Solutions of each lubricant of 30% by weight were prepared in a solvent. Steel wool wedges were weighed and then soaked in the contaminated solvent, drained, and dried at 100°C for 30 minutes. The wedges were reweighed and the weight of the retained lubricant recorded. The impregnated wedges were then placed in short glass tubes and washed with 3 mL of the test solvent. The wedges were then drained, dried, and weighed as before. The grams of soil lost per milliliter of test solvent gives a measure of the solvating power. The final data was normalized to nPB = 1.0.
The environmental impact and health hazards of cleaning
Published in Rajkishore Nayak, Saminathan Ratnapandian, Care and Maintenance of Textile Products Including Apparel and Protective Clothing, 2018
Rajkishore Nayak, Saminathan Ratnapandian
Brominated solvents: These are n-propyl bromide-based solvents with a higher Kauri-butanol(KB) value than perc (a KB value is an international terminology used to measure the solvency power of a solvent based on hydrocarbon, which is specified in the ASTM standard: ASTM D1133). The higher KB value helps in the faster cleaning than perc. However, improper use can damage the buttons, sequins and beads. It is available in trade names such as Fabrisolv and DrySolv. In dry cleaning, the exposure to the solvent does not pose any health risk. Therefore, it is being approved by the EPA as a significant new alternative solvent compared to the traditional hazardous solvents. However, excessive exposure can lead to numbness of the nerves. Although the solvent is expensive, the cost is counterbalanced by its faster cleaning action, lower temperature and quick dry times. The overall dry cleaning cost per garment is found to be the same or lower compared to perc.
Chlorinated Solvents and Solvent Stabilizers
Published in Thomas K.G. Mohr, William H. DiGuiseppi, Janet K. Anderson, James W. Hatton, Jeremy Bishop, Barrie Selcoe, William B. Kappleman, Environmental Investigation and Remediation, 2020
Dow Chemical markets “MaxiStab,” a series of stabilizer concentrates used to replenish stabilizers in different grades of solvents. In low-emission degreasing systems, stabilizers are depleted faster than they are replenished by the addition of fresh solvent. The MaxiStab line of stabilizer concentrates are tailored to each of Dow's chlorinated solvent lines, underscoring the specialization of stabilizer packages for specific applications (Dow Chemical Company, 2006b). A stabilizer concentrate is currently sold for newer lines of degreaser solvents, such as n-propyl bromide; the contents may include 1,2-butylene oxide, dimethoxymethane, and 2-methyl-2-propanol, as well as other compounds (Petroferm, Inc., 2005).
In-situ approach for the synthesis of bromide-bridged mercury(II) N-heterocyclic carbene complexes
Published in Journal of Coordination Chemistry, 2020
Muhammad Atif, Haq Nawaz Bhatti, Muhammad Adnan Iqbal, Yasir Jamil
A solution of 1-propyl benzimidazole (1.6 g, 10 mmol) and n-propyl bromide (1) (1.23 g, 10 mmol) in dioxane (50 mL) was stirred for 24 h under reflux, and a pale yellow oily product was obtained by decantation of the solvent (Scheme 1). The oily product was washed with fresh dioxane (3 × 5 mL) and diethyl ether (2 × 5 mL) and stored in vacuum desiccators [31]. Yield: 73.1%. M.P.: 246 °C, 1H NMR (500 MHz, DMSO-d6): δ 0.90 (t, 6H, 2 × CH3, J = 7.5 Hz), 1.95 (sext, 4H, 2 × CH2), 4.55 (t, 4H, 2 × N-CH2-R, J = 7.5 Hz), 7.66 (sext, 2H, Ar-H), 8.16 (sext, 2H, Ar-H), 10.21 (s, 1H, NCHN). 13C NMR (125.7 MHz, DMSO-d6): δ 10.6 (CH3), 22.0 (CH2), 48.1 (N-CH2-R), 113.7, 126.4, 131.0 (Ar-C), 142.1 (NCN). FT-IR (KBr disc) in cm−1: 3138, 3036 (C-Harom), 2969, 2933, 2862 (C-Haliph), 1045, ∼1210 cm−1 (Carom-Nbenzimi). Anal. Calcd for C13H19N2Br: C, 55.1; H, 6.7; N, 9.8%. Found: C, 55.9; H, 8.8; N, 7.4%.
Evaluation of solvents for asphalt extraction
Published in Road Materials and Pavement Design, 2021
Peter Mikhailenko, Glenn Webber, Hassan Baaj
Due to the health and safety and environmental concerns with Trichloroethylene, an alternative solvent known as n-Propyl Bromide (nPB/C3H7Br) was introduced to asphalt extraction and recovery in the 1990s, also having been used as a degreasing and cleaning solvent (Stroup-Gardiner & Nelson, 2000). At the time of its introduction in the late 1990s, nPB had not been designated a carcinogen. It was found, however, to cause irritation to the lungs. There had also been some skin and eye irritation associated with its use, hence and it was recommended for use in a well-ventilated area to avoid headaches, dizziness and nausea by the user (Collins-Garcia et al., 2000), so therefore it was a less than ideal replacement for chlorinated solvents from the start.
Rheological, permanent deformation and fatigue analysis for calibration of the recovery process of bitumens in the rotary evaporator
Published in Road Materials and Pavement Design, 2023
Pedro Orlando Borges de Almeida Júnior, Silvio Lisboa Schuster, Cléber Faccin, Pablo Menezes Vestena, Pedro Schmidt Ilha, Gustavo Menegusso Pires, Edson Irineu Müller, Deividi da Silva Pereira, Luciano Pivoto Specht
Diefenderfer (2014) compared the three base bitumen spectroscopies with those of the same bitumens mixed with n-propyl bromide (nPB) and recovered using a rotary evaporator and by the Abson method. Both methods significantly changed specific measured bitumens properties based on a comparison of recovered bitumens blanks and unrecovered base bitumens. However, the author also did not identify the residual solvent presence by the FTIR test, indicating that the solvent may be present at such low concentrations that the bitumens peaks overtake them on the infrared scan.