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Cleaning Validation for the Pharmaceutical, Biopharmaceutical, Cosmetic, Nutraceutical, Medical Device and Diagnostic Industries
Published in James Agalloco, Phil DeSantis, Anthony Grilli, Anthony Pavell, Handbook of Validation in Pharmaceutical Processes, 2021
Commodity chemicals such as sodium hydroxide (NaOH) can be used for cleaning as well. Like their solvent counterparts, there may be hazard issues and effluent issues associated with these materials. Their typically high alkalinity or low acidity, however, often makes them effective at hydro-lysis, oxidation and reduction of soils, which makes them helpful in inactivation processes. However, these chemicals lack the detergency of a formulated cleaning agent, and they may be inadequate to rinse degraded residues free from systems, taking larger volumes of water than would a formulated cleaning agent.
Common Sense Emergency Response
Published in Robert A. Burke, Common Sense Emergency Response, 2020
Sodium hydroxide (lye) is found as white pellets or flakes that are odorless. It is a reagent used in the manufacture of methamphetamine. Sodium hydroxide is extremely corrosive. When in contact with metals such as sodium or fire, it can produce explosive hydrogen gas.
Development of Sustainable Biobased Polymer and Bio-Nanocomposite Materials Using Nanocellulose Obtained from Agricultural Biomass
Published in Linda Godfrey, Johann F Görgens, Henry Roman, Opportunities for Biomass and Organic Waste Valorisation, 2020
A Mtibe, S Muniyasamy, TE Motaung
The main aim of treating cellulosic fibres with alkali is to solubilise hemicellulose, lignin and extractives (Rosa et al., 2010). Sodium hydroxide (NaOH) and potassium hydroxide (KOH) are commonly used alkalis. The treatment with alkali at higher temperatures of about 75ºC to 80ºC is used for solubilisation process (Motaung & Mtibe, 2015). A treatment with strong alkali could affect the crystallinity of the cellulose and degradation could occur (Ridzuan et al., 2015). Following alkaline treatment, the material undergoes several repetitions of washes with water until a neutral pH level is achieved. This treatment swells the fibres and leaves some traces of alkali. These remaining traces of alkali make the fibres more accessible to other chemical treatments and mechanical processes.
A quantitative analysis method to determine the amount of cellulose fibre in waste sludge
Published in Environmental Technology, 2021
Kurumi Hashimoto, Narumi Kubota, Toru Marushima, Masaki Ohno, Satoshi Nakai, Hiroshi Motoshige, Wataru Nishijima
For alkaline hydrolysis, potassium hydroxide or sodium hydroxide solution was used. Both alkaline concentrations were adjusted from 1 to 16 mM by diluting 48% potassium hydroxide (Kanto Chemical) or 48% sodium hydroxide solution (Kanto Chemical) with MilliQ water, respectively, and 20 mL of alkaline solution were added to 20 mL of samples in 50 mL polypropylene centrifuge tubes. The mixture was reacted for 1 h at room temperature or 60°C in a water bath.
Evaluation and optimization of preparation for semi-coke briquette with alkali-heat treated wheat straw binder
Published in International Journal of Coal Preparation and Utilization, 2022
Maobo Yuan, Chang’An Wang, Lin Zhao, Zhengrong Zhu, Pengqian Wang, Chaowei Wang, Defu Che
Binding agents play an essential role in briquetting process, which could be divided into organic agents, inorganic agents, and compound agents (Zhang, Sun, and Xu 2018). Inorganic agents usually have good thermal stability and low price, and the calcium oxide possesses good sulfur retention. While the durability of briquette with inorganic binder could hardly meet the storage requirement. On the contrary, organic agents perform well in mechanical properties and heat value but struggle in thermal stability and water resistance (Paul et al. 2002; Thoms, Snape, and Taylor 1999). Although the tar and its residue supply strong cohesion for coal particles, a large amount of polycyclic aromatic hydrocarbons (PAHs) could generate in the carbonization process of tar (Montiano et al. 2015). Compared with polymer binder, biomass binder has the characteristics of abundant reserve and low price (Muazu and Stegemann 2017). Thus, much research has been conducted on densification of biomass into bio-coal briquettes or bio-briquettes. Yaman et al. (Yaman et al. 2001) produced the briquettes from the blends of lignite and biomass within the forming pressure range of 50–250 MPa. The compressive strengths of bio-coal briquettes were improved when the addition ratio of pine cone, sawdust, and paper mill waste was above 20%. While the forming pressure was relatively high, this brought large electricity consumption and heavy mechanical wear to the briquetting process. There were great differences in the chemical characteristics and structure between biomass and coal, and the direct addition of biomass to coal decreased the thermoplastic properties of molded coal (Florentino-Madiedo et al. 2018a). Wu et al. (Wu et al. 2018) used the biomass pretreated by hydrothermal method at 230°C to produce high-strength briquette, the macromolecular organic compounds, polar functional groups, glass transition behavior, and larger surface area of hydrolyzed biomass made great contributions. Lu et al. (Lu, Cheng, and Li 2015) and Zhang et al. (Zhang et al. 2001) used the corn stalk and rice straw treated with sodium hydroxide as molded coal agents, respectively. Partial components in decomposed biomass such as sugars, pectin and lignin had strong binding and stretch properties (Castellano et al. 2015; Li et al. 2012), and the ignition and burnout temperatures of briquette could be reduced by increasing the biomass in the proportion. While the price of sodium hydroxide is relatively high, several studies employed calcium hydroxide for the alternative to reduce the cost. Kong et al. (Kong et al. 2013) found out that the blended agent comprised by alkaline lignin and calcium hydroxide could strengthen the cohesion and improve the water-resistant effect of sawdust char pellets. Zhang et al. (Zhang et al. 2001) found that the solid part of rice straw treated with 6.7% of lime had a good binding effect, while the binding ability of the liquor part was weak. The investigation on alkali-heat treatment of biomass mainly discussed the alkali concentration, heating temperature, and processing time. The optimum-treated biomass binder ratio and forming pressure in briquette preparation are still to be thrashed out.