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Determination and correlation of liquid-liquid equilibrium of water + furfuryl alcohol + extractant
Published in Binoy K. Saikia, Advances in Applied Chemistry and Industrial Catalysis, 2022
Houchun Yan, Qingqing Yin, Yuanyuan Han, Mai Han, Qingsong Li
Furfuryl alcohol is a significant raw material for the production of furan resin. The purity of its industrial products is greater than 98%, and the water content is less than 0.3%. Due to the low requirement for water content, a large amount of wastewater needs to be removed in the production of furfuryl alcohol (Meng et al. 2016; Sharma et al. 2013; Vargas-Hernández et al. 2014). In addition, in the production process of 2-methylfuran and other products, wastewater will also be produced, which contains about 10% furfuryl alcohol. Based on the annual output of 5000 tons of 2-methylfuran, the furfuryl alcohol contained in the produced furfuryl alcohol wastewater was calculated to be about 420 t/a (Zhao et al. 2020). According to GC-MS analysis of furfuryl alcohol wastewater, there are more than 40 kinds of organic substances (furfuryl alcohol, acetic acid, furfural and other alcohols, aldehydes, ketones, esters and organic acids). Furfuryl alcohol wastewater is difficult to treat, with low biodegradability and great damage to the environment and ecology. It is a highly difficult organic wastewater. At present, there are few studies on the treatment of furfuryl alcohol wastewater (Xiong et al. 2020). Generally, the wastewater containing furfuryl alcohol will be biochemically treated with other heavy phase organics together in industry. The cost of this treatment method is high, requiring about 2000-3000 RMB per ton (Zhao et al. 2020). Therefore, the reasonable treatment of these wastewater is very important.
Basic Materials Engineering
Published in David A. Hansen, Robert B. Puyear, Materials Selection for Hydrocarbon and Chemical Plants, 2017
David A. Hansen, Robert B. Puyear
Normal fine-grain graphite is porous. To make it impervious, it is usually impregnated with organic resins such as phenolic or furan prior to the final heat treatment. A phenolic resin is used for resistance to most acids, salt solutions and organic compounds. A furan resin is used for materials to be used in alkaline and oxidizing services.
Polymers
Published in Bryan Ellis, Ray Smith, Polymers, 2008
Processing & Manufacturing Routes: Synth. [2,9,11] by polymerisation of furfuryl alcohol under acid catalysis (PH 3-5) at 80- 100° with the reaction rate moderated by external cooling. If a liq. resin is desired [10], the mixture is neutralised. Otherwise, the resin is cured in situ using acids such as p-toluenesulfonic acid to give dark solids. Processed by transfer and compression press moulding; extrusion is possible but is not reasonable for many requirements [8]. Furfuryl alcohol-formaldehyde copolymer may be synth. by reaction of 1 mole furfuryl alcohol with 0.5 -0.75 mole aq. formaldehyde in the presence of oxalic acid catalyst. Alternatively, paraformaldehyde may be employed and an organic medium used [7]. Latent cure agents used for heat cure, sulfonic acids used for cure at lower temp. A furan resin two-component system can be mixed with a range of fillers to produce chemically- resistant compositions. Furan resins with latent heat curing catalyst are used as chemically-resistant coatings for chemical process equipment. A Furan resin two-component system can be used for refractory mixes by a cold-mixing process. In the foundry, for the hot box process, quartz sand is batch mixed with urea- modified furan resin (1.4-2%) and latent curing agent e.g. ammonium nitrate (0.3-0.5%). The mix is shaped and precured at 200 -2608 for up to 2 min in core boxes. Use of modified furan resins (0.9 -1.2%) with curing agents (0.2-0.4%, usually sulfonic acids) enables a warm-box process for binding sand at 140-200°. Furan resins with special curing agents may be employed in a vacuum warm box process where the corebox is heated at 70 - 1008. For a no-bake process, sand and phenolic resole or furan resin (0.7 -1.3%) and an acidic curing agent (0.2-0.6%) are cured at ambient temps. for 20 mins to several hours. Binding of foundry sand is also done using furan resins (0.8 -2%) with peroxide hardeners (0.3 -0.9%) in the Hardox process. Applications: Chemically-resistant putties using furan resins have exceptional solvent and alkali resistance. They are used as bonding and grouting materials for industrial floors and walls. Industrail concrete and screed-topped floors are protected by laminated coatings e.g. furan resin and fibrous filler. Chemical processing equipment may be coated with filled furan resin systems to enhance chemical resistance. Shaped refractory products can be made using furan resins by a cold-mixing technique. Furan resins (homopolymers of 2-furanmethanol) may be carbonised to produce glassy carbon parts; active carbon materials e.g. molecular sieve, catalysts; and graphitised films. Furfuryl alcohol resins used mainly in the foundry industry as sand binders for casting moulds and cores. Applications due to good corrosion resistance in mortar, cement, waste disposal systems and sewers. As rapid repair materials in oilfield applications; in adhesives and binders in wood technology. Also used to make impregnating solns. to improve the imperviousness of materials. Glass-reinforced grades used in piping. Furfuryl alcohol-formaldehyde copolymer used in adhesives and as a binder
Optimization of dry compressive strength of groundnut shell ash particles (GSAp) and ant hill bonded foundry sand using ann and genetic algorithm
Published in Cogent Engineering, 2019
Chidozie Chukwuemeka Nwobi-Okoye, Patrick Chukwuka Okonji, Stanley Okiy
Usually, various additives are added to sand to make it suitable for use as foundry sand. Some of these additives such as synthetic resins, like Furan resin and phenol-formaldehyde resins are hazardous and are not environmentally friendly. Moreover, these binder systems are too sophisticated and expensive for foundries in developing countries that have abundant natural raw materials but without needed advanced technologies for proper use of the resources. In this regard, Okonji, Nwobi-Okoye, and Atanmo (2018) developed a cheap and eco-friendly binding material using groundnut shell ash (GSAp) and ant hill soil for green and dry sand casting application in Nigerian foundries. Dry sand casting involves baking the mould in an oven at a certain temperature for a given time period in order to strengthen the mould before casting. Dry sand casting is much more expensive than green sand casting and it is usually used for casting intricate shapes and complex parts used in machines and equipment. Obtaining the high compressive strength required for dry sand casting comes at a cost because as the strength increases the cost of the mould increases. This is a typical case of conflicting objectives because the engineer often desires high strength at a minimum cost. Hence, in order to optimize the mould required for dry sand casting, a multi-objective optimization is required.