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Clay Mineral Catalysis of Isomerization, Dimerization, Oligomerization, and Polymerization Reactions
Published in Benny K.G. Theng, Clay Mineral Catalysis of Organic Reactions, 2018
The synthesis of high-density fuels through the selective dimerization of α-pinene, camphene, limonene, and crude turpentine over various solid acid catalysts, including K10 montmorillonite, has been reported by Meylemans et al. (2012). The dimerization and trimerization of aromatic hydrocarbons (e.g., naphthalene), hydroxylated aromatics (e.g., 2-naphthol), and methyl-substituted aromatics (e.g., 2-methylnaphthalene) in the presence of Fe3+-montmorillonite may be ascribed to oxidative coupling, which involves the reduction of exchangeable Fe3+ to Fe2+ (Watson and Sephton 2015). This process and related clay-catalyzed Fenton-like oxidation reactions will be described in Chapter 7. Wiederrecht et al. (2001) have also noted that pyrene can form face-to-face dimers in the interpillar space of alumina-pillared montmorillonite (cf. Figure 3.2), allowing 5%–6% w/w of the monomer to be loaded whereas other aromatic hydrocarbons such as benzene, naphthalene, and perylene show only limited incorporation.
Naturally Occurring Polymers—Plants
Published in Charles E. Carraher, Carraher's Polymer Chemistry, 2017
Early progress toward the use of NR in Europe is attributed to Charles Macintosh and Thomas Hancock. NR was dissolved in relatively expensive solvents such as turpentine and camphene. The earliest applications were made by pouring these solutions containing NR onto objects to be “rubberized.” Later, other less expensive solvents were discovered, including the use of coal-tar naphtha. Macintosh poured naphtha solutions containing the NR onto layers of cloth producing “waterproof” material, which was the origin of the Macintosh raincoat, misspelled by the English as “Mackintoshes.” The layering of the NR not only produced a material that was waterproof, but also got around the problem that NR was sticky, becoming more sticky on hot days. NR also had an unpleasant odor that was somewhat captured and prevented from smelling up the place by placement between pieces of cloth. Hancock, an associate of Macintosh, worked to develop other useful rubbers from NR. One of his first was rubber thread derived from cutting strips of NR and applied to cloths and footwear. He had lots of scraps and found that by heating the scraps he could reform sheets of the NR from which he could cut more strips. He also developed a crude mixing machine that allowed him to mix other materials, additives, into the rubber.
Terpenes and Terpenoids
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
Camphor can be produced from α-pinene, which is abundant in the oils of coniferous trees and can be distilled from turpentine produced as a side product of chemical pulping. With acetic acid as the solvent and with catalysis by a strong acid, α-pinene readily rearranges into camphene, which in turn undergoes Wagner–Meerwein rearrangement into the isobornyl cation, which is captured by acetate to give isobornyl acetate. Hydrolysis into isoborneol followed by oxidation gives racemic camphor. By contrast, camphor occurs naturally as d-camphor, the (r)-enantiomer.
Eco-friendly management strategies of insect pests: long-term performance of rosemary essential oil encapsulated into chitosan and gum Arabic
Published in International Journal of Environmental Health Research, 2023
Abir Soltani, Sarra Ncibi, Tasnim Djebbi, Amina Laabidi, Hela Mahmoudi, Jouda Mediouni-Ben Jemâa
Studies conducted in Tunisia have revealed that 1,8-cineole is the predominant compound found in the essential oil of R. officinalis. Other compounds such as camphor, α-pinene, Borneol, camphene, transcaryophyllene, and α-thujone have also been reported (Farhat et al. 2017; Selmi et al. 2017; Abada et al. 2019). The essential oil, along with its major constituents, shows potential as an environmentally friendly alternative to synthetic pesticides and herbicides (Al-Maqtari et al. 2021). Furthermore, studies by Bachrouch et al. (2014) and Dugrand et al. (2013) have demonstrated that the high toxicity effects of the essential oil can be attributed to its abundance of major compounds. Similarly, previous research has highlighted that 1,8-cineole is the major component of R. officinalis (Dammak et al. 2019).
Postharvest blanching and drying of industrial hemp (Cannabis sativa L.) with infrared and hot air heating for enhanced processing efficiency and microbial inactivation
Published in Drying Technology, 2023
Chang Chen, Ke Wang, Ivan Wongso, Zhaokun Ning, Ragab Khir, Daniel Putnam, Irwin R. Donis-González, Zhongli Pan
Ultrapure water for HPLC analysis was prepared using a Milli-Q® Integral 10 system (Millipore Sigma, Saint Louis, USA); LC-grade chemicals for HPLC analysis, including formic acid, acetonitrile, methanol, ethanol, iso-propanol and n-hexane were purchased from Sigma Aldrich (St. Louis, MO. USA). Standard LC-grade CBD (C045) and CBDA (C046) were purchased from Sigma Aldrich for HPLC method development and calibration curve preparation. Standard terpene compounds that contain: α-Pinene, Camphene, β-Pinene, β-Myrcene, δ-Limonene, β-Ocimene, Ocimene, γ-Terpinene, Linalool, β-Caryophyllene, α-Humulene, Cis-Nerolidol, Trans-Nerolidol, Caryophyllene Oxide and Guaiol (Sigma Aldrich) were owned by Harrens Lab Inc. (Hayward, California, USA) for GC analysis and. Phosphate, acetate, Sodium hydroxide, 3-methyl-2-benzothiazolinone hydrazone, and hydrogen hydroxide of analytical grade were purchased from Sigma Aldrich.
Turpentine oil: a novel and natural bridging liquid for agglomeration of coal fines of high ash coals
Published in International Journal of Coal Preparation and Utilization, 2022
Saswati Chakladar, Riya Banerjee, Ashok Mohanty, Sanchita Chakravarty, Prasanjeet Kumar Patar
To complement the rapid rate of discovery of suitable bridging oils, we selected to delve into an in-depth study of coal agglomeration using turpentine oil, which is isolated from natural resources. Turpentine oil is derived from the oleoresin collected from certain pine trees. Distillation of this natural material produces turpentine oil and the solid rosin. It is generally composed of α-pinene, β-pinene, limonene and camphene as the key chemical constituents (Figure 1). An interesting fact has been stated by Wang et al. regarding improvement in agglomeration efficiency based on structural parity of oil and carbonaceous matter in coal (Wang et al. 2012). The carbocyclic structure of the chemical components in turpentine oil made us even more inquisitive toward testing its efficiency for oil agglomeration of high-grade coals that primarily consist of π-delocalized aromatic structures.