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55-729: The Nakdong River flows from the Taebaek Mountains to the South Sea or Korea Strait , which separates Korea from Japan. The river originates from the junction of the Cheolamcheon and Hwangjicheon streams in Dongjeom-dong, Taebaek , Gangwon Province . From there to its mouth it winds for about 506 kilometres (314 mi). The width of the river ranges from only a few metres in its upper reaches to several hundred metres towards its estuary . Major tributaries include

110-554: A bis(2-hydroxyphenyl) derivative, and a 4-cyclohexylphenols. Alcohols and hydroperoxides alkylate phenols in the presence of solid acid catalysts (e.g. certain zeolite ). Cresols and cumyl phenols can be produced in that way. Aqueous solutions of phenol are weakly acidic and turn blue litmus slightly to red. Phenol is neutralized by sodium hydroxide forming sodium phenate or phenolate, but being weaker than carbonic acid , it cannot be neutralized by sodium bicarbonate or sodium carbonate to liberate carbon dioxide . When

165-463: A chemical could be used to destroy the micro-organisms that cause infection. Meanwhile, in Carlisle , England, officials were experimenting with sewage treatment using carbolic acid to reduce the smell of sewage cesspools . Having heard of these developments, and having previously experimented with other chemicals for antiseptic purposes without much success, Lister decided to try carbolic acid as

220-422: A derivative of benzene, in 1841. In 1836, Auguste Laurent coined the name "phène" for benzene; this is the root of the word "phenol" and " phenyl ". In 1843, French chemist Charles Gerhardt coined the name "phénol". The antiseptic properties of phenol were used by Sir Joseph Lister in his pioneering technique of antiseptic surgery. Lister decided that the wounds had to be thoroughly cleaned. He then covered

275-622: A favored dwelling-place for as long as people have inhabited the Korean peninsula . Numerous Neolithic remains have been found in the valley. Around the 1st century, the valley is believed to have been inhabited by the Byeonhan confederacy tribes. During the Three Kingdoms period , the Gaya confederacy controlled the valley until they were overrun by Silla in 562. These states exploited

330-441: A key precursor to polycarbonates and epoxide resins. Condensation of phenol, alkylphenols , or diphenols with formaldehyde gives phenolic resins , a famous example of which is Bakelite . Partial hydrogenation of phenol gives cyclohexanone , a precursor to nylon . Nonionic detergents are produced by alkylation of phenol to give the alkylphenols , e.g., nonylphenol , which are then subjected to ethoxylation . Phenol

385-426: A major commercial waterway, the river continues to feed those dwelling near it, both directly through fishing and indirectly through irrigation. Substantial amounts of snails and catfish are taken from the waters and used in local cuisine. Near Andong , a series of massive hydroelectric dams have been constructed, creating a small chain of artificial lakes of which Andong Lake is the largest. These lakes also support

440-425: A mixture of 2-nitrophenol and 4-nitrophenol while with concentrated nitric acid, additional nitro groups are introduced, e.g. to give 2,4,6-trinitrophenol . Friedel Crafts alkylations of phenol and its derivatives often proceed without catalysts. Alkylating agents include alkyl halides, alkenes, and ketones. Thus, adamantyl-1-bromide , dicyclopentadiene ), and cyclohexanones give respectively 4-adamantylphenol,

495-493: A mixture of phenol and benzoyl chloride are shaken in presence of dilute sodium hydroxide solution, phenyl benzoate is formed. This is an example of the Schotten–Baumann reaction : Phenol is reduced to benzene when it is distilled with zinc dust or when its vapour is passed over granules of zinc at 400 °C: When phenol is treated with diazomethane in the presence of boron trifluoride ( BF 3 ), anisole

550-542: A mountain range that stretches across North Korea and South Korea . They form the main ridge of the Korean peninsula . The Taebaek mountains are located along the eastern edge of the peninsula and run along the eastern coast of the Korean Peninsula. The Hwangnyong Mountain in North Korea (1268 meters) forms the northern end of the range. Busan lies at the southern end of this mountain range, thus making

605-746: A substantial recreational industry. Bass fishing is especially popular, since the lakes have been artificially stocked with bass . In the early 2010s, the Nakdonggang River was to be part of President Lee Myung-bak 's canal project, the Grand Korean Waterway . The project would link the Nakdong with the Han River to the north, creating a shipping canal spanning length of the country, from Seoul to Busan. Encountering considerable controversy nationwide as well as from residents along

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660-422: A wide range of Lewis bases such as pyridine , diethyl ether , and diethyl sulfide . The enthalpies of adduct formation and the −OH IR frequency shifts accompanying adduct formation have been compiled. Phenol is classified as a hard acid . Phenol exhibits keto-enol tautomerism with its unstable keto tautomer cyclohexadienone, but the effect is nearly negligible. The equilibrium constant for enolisation

715-416: A wound antiseptic. He had his first chance on August 12, 1865, when he received a patient: an eleven-year-old boy with a tibia bone fracture which pierced the skin of his lower leg. Ordinarily, amputation would be the only solution. However, Lister decided to try carbolic acid. After setting the bone and supporting the leg with splints, he soaked clean cotton towels in undiluted carbolic acid and applied them to

770-451: A year) from petroleum -derived feedstocks. It is an important industrial commodity as a precursor to many materials and useful compounds. It is primarily used to synthesize plastics and related materials. Phenol and its chemical derivatives are essential for production of polycarbonates , epoxies , explosives , Bakelite , nylon , detergents , herbicides such as phenoxy herbicides , and numerous pharmaceutical drugs . Phenol

825-424: Is a weak acid (pH 6.6). In aqueous solution in the pH range ca. 8 - 12 it is in equilibrium with the phenolate anion C 6 H 5 O (also called phenoxide or carbolate ): Phenol is more acidic than aliphatic alcohols. Its enhanced acidity is attributed to resonance stabilization of phenolate anion. In this way, the negative charge on oxygen is delocalized on to the ortho and para carbon atoms through

880-403: Is absorbed through the skin relatively quickly, systemic poisoning can occur in addition to the local caustic burns. Resorptive poisoning by a large quantity of phenol can occur even with only a small area of skin, rapidly leading to paralysis of the central nervous system and a severe drop in body temperature. The LD 50 for oral toxicity is less than 500 mg/kg for dogs, rabbits, or mice;

935-402: Is also a versatile precursor to a large collection of drugs, most notably aspirin but also many herbicides and pharmaceutical drugs . Phenol is a component in liquid–liquid phenol–chloroform extraction technique used in molecular biology for obtaining nucleic acids from tissues or cell culture samples. Depending on the pH of the solution either DNA or RNA can be extracted. Phenol

990-436: Is an aromatic organic compound with the molecular formula C 6 H 5 OH . It is a white crystalline solid that is volatile . The molecule consists of a phenyl group ( −C 6 H 5 ) bonded to a hydroxy group ( −OH ). Mildly acidic , it requires careful handling because it can cause chemical burns . Phenol was first extracted from coal tar , but today is produced on a large scale (about 7 million tonnes

1045-537: Is an organic compound appreciably soluble in water, with about 84.2 g dissolving in 1000 ml (0.895 M ). Homogeneous mixtures of phenol and water at phenol to water mass ratios of ~2.6 and higher are possible. The sodium salt of phenol, sodium phenoxide , is far more water-soluble. It is a combustible solid (NFPA rating = 2). When heated, phenol produces flammable vapors that are explosive at concentrations of 3 to 10% in air. Carbon dioxide or dry chemical extinguishers should be used to fight phenol fires. Phenol

1100-539: Is approximately 10 , which means only one in every ten trillion molecules is in the keto form at any moment. The small amount of stabilisation gained by exchanging a C=C bond for a C=O bond is more than offset by the large destabilisation resulting from the loss of aromaticity. Phenol therefore exists essentially entirely in the enol form. 4, 4' Substituted cyclohexadienone can undergo a dienone–phenol rearrangement in acid conditions and form stable 3,4‐disubstituted phenol. For substituted phenols, several factors can favor

1155-608: Is highly reactive toward electrophilic aromatic substitution . The enhanced nucleophilicity is attributed to donation pi electron density from O into the ring. Many groups can be attached to the ring, via halogenation , acylation , sulfonation , and related processes. Phenol is so strongly activated that bromination and chlorination lead readily to polysubstitution. The reaction affords 2- and 4-substituted derivatives. The regiochemistry of halogenation changes in strongly acidic solutions where PhOH 2 ] predominates. Phenol reacts with dilute nitric acid at room temperature to give

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1210-448: Is obtained as the main product and nitrogen gas as a byproduct. Phenol and its derivatives react with iron(III) chloride to give intensely colored solutions containing phenoxide complexes. Because of phenol's commercial importance, many methods have been developed for its production, but the cumene process is the dominant technology. Accounting for 95% of production (2003) is the cumene process , also called Hock process . It involves

1265-452: Is possible, but it has not been commercialized: Nitrous oxide is a potentially "green" oxidant that is a more potent oxidant than O 2 . Routes for the generation of nitrous oxide however remain uncompetitive. An electrosynthesis employing alternating current gives phenol from benzene. The oxidation of toluene , as developed by Dow Chemical , involves copper-catalyzed reaction of molten sodium benzoate with air: The reaction

1320-466: Is proposed to proceed via formation of benzyoylsalicylate. Autoxidation of cyclohexylbenzene give the hydroperoxide . Decomposition of this hydroperoxide affords cyclohexanone and phenol. Early methods relied on extraction of phenol from coal derivatives or the hydrolysis of benzene derivatives. The original commercial route was developed by Bayer and Monsanto in the early 1900s, based on discoveries by Wurtz and Kekule. The method involves

1375-462: Is so inexpensive that it also attracts many small-scale uses. It is a component of industrial paint strippers used in the aviation industry for the removal of epoxy, polyurethane and other chemically resistant coatings. Due to safety concerns, phenol is banned from use in cosmetic products in the European Union and Canada . Phenol was widely used as an antiseptic , and it is used in

1430-488: Is used medically to treat sore throat. It is the active ingredient in some oral analgesics such as Chloraseptic spray, TCP and Carmex . Phenol was discovered in 1834 by Friedlieb Ferdinand Runge , who extracted it (in impure form) from coal tar . Runge called phenol "Karbolsäure" (coal-oil-acid, carbolic acid). Coal tar remained the primary source until the development of the petrochemical industry . French chemist Auguste Laurent extracted phenol in its pure form, as

1485-730: The Han River and the Nakdong River , both originate in the Taebaek Mountains. Many of the slopes are extensively covered in forests. Economically, the Taebaek mountains are important for the mining of iron , coal , tungsten , fluorite , and limestone . Manggyeongsa Temple in Hyeol-dong Taebaek , Gangwon-do Province at an altitude of 1,460 meters on Mount Taebaeksan , is a temple built to enshrine

1540-526: The Yeong , Geumho , and Nam rivers. Together with its tributaries , the Nakdonggang drains most of North Gyeongsang and South Gyeongsang provinces, along with small portions of North Jeolla , South Jeolla , and Gangwon provinces. The total watershed is 23,384 square kilometres (9,029 sq mi). The Nakdong has played an important role throughout Korean history . The river basin has been

1595-425: The p K a of the enol of acetone in water is 10.9, making it only slightly less acidic than phenol (p K a 10.0). Thus, the greater number of resonance structures available to phenoxide compared to acetone enolate seems to contribute little to its stabilization. However, the situation changes when solvation effects are excluded. In carbon tetrachloride and in alkane solvents, phenol hydrogen bonds with

1650-652: The Busan New Port), the ongoing construction of a major bridge (the Miyeonji Bridge) and most recently the threatened construction of the Korean Grand Canal project. The Nakdonggang and its tributaries serve as a major source of drinking water for the inhabitants of the river basin and others nearby. However, water pollution from domestic and agricultural wastewater remains a serious concern. In 1991, there were two incidents where phenol

1705-737: The Junamjeosuji Reservoir near Changwon and Upo Wetland in Changnyeong County . These wetlands, while significantly degraded and overdeveloped, provide habitat to a significant number of rare and threatened species, most especially birds (such as the Baikal teal and White-naped crane ), fish and plants. Despite being home to the bustling Port of Busan , the Nakdonggang estuary is internationally important for waterbirds, despite recent ecologically-destructive developments including reclamation for housing and industry (e.g.

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1760-572: The Lancet, he had treated a total of eleven patients using his new antiseptic method. Of those, only one had died, and that was through a complication that was nothing to do with Lister's wound-dressing technique. Now, for the first time, patients with compound fractures were likely to leave the hospital with all their limbs intact Before antiseptic operations were introduced at the hospital, there were sixteen deaths in thirty-five surgical cases. Almost one in every two patients died. After antiseptic surgery

1815-532: The Nakdonggang, the waterway project was scrapped by the end of Lee's presidency. The Nakdong River Cultural Center holds bicycle festivals that everyone can enjoy the healthy leisure culture of local residents. It is composed of flat courses about 20 km in the vicinity of Eulsukdo and Nakdonggang River Cultural Center. 35°03′06″N 128°55′21″E  /  35.05167°N 128.92250°E  / 35.05167; 128.92250 Taebaek Mountains The Taebaek Mountains ( Korean :  태백산맥 ) are

1870-635: The amount in the distillate. Cryptanaerobacter phenolicus is a bacterium species that produces benzoate from phenol via 4-hydroxybenzoate . Rhodococcus phenolicus is a bacterium species able to degrade phenol as sole carbon source. Phenol and its vapors are corrosive to the eyes, the skin, and the respiratory tract. Its corrosive effect on skin and mucous membranes is due to a protein-degenerating effect. Repeated or prolonged skin contact with phenol may cause dermatitis , or even second and third-degree burns. Inhalation of phenol vapor may cause lung edema . The substance may cause harmful effects on

1925-437: The central nervous system and heart, resulting in dysrhythmia , seizures , and coma . The kidneys may be affected as well. Long-term or repeated exposure of the substance may have harmful effects on the liver and kidneys . There is no evidence that phenol causes cancer in humans. Besides its hydrophobic effects, another mechanism for the toxicity of phenol may be the formation of phenoxyl radicals . Since phenol

1980-623: The central nervous system causes sudden collapse and loss of consciousness in both humans and animals; a state of cramping precedes these symptoms because of the motor activity controlled by the central nervous system. Injections of phenol were used as a means of individual execution by Nazi Germany during the Second World War . It was originally used by the Nazis in 1939 as part of the mass-murder of disabled people under Aktion T4 . The Germans learned that extermination of smaller groups

2035-568: The chloride byproduct. Phenol is also a recoverable byproduct of coal pyrolysis. In the Lummus process , the oxidation of toluene to benzoic acid is conducted separately. Phenyldiazonium salts hydrolyze to phenol. The method is of no commercial interest since the precursor is expensive. Salicylic acid decarboxylates to phenol. The major uses of phenol, consuming two thirds of its production, involve its conversion to precursors for plastics. Condensation with acetone gives bisphenol-A ,

2090-462: The cumene process. A route analogous to the cumene process begins with cyclohexylbenzene . It is oxidized to a hydroperoxide , akin to the production of cumene hydroperoxide . Via the Hock rearrangement, cyclohexylbenzene hydroperoxide cleaves to give phenol and cyclohexanone . Cyclohexanone is an important precursor to some nylons . The direct oxidation of benzene ( C 6 H 6 ) to phenol

2145-412: The keto tautomer: (a) additional hydroxy groups (see resorcinol ) (b) annulation as in the formation of naphthols , and (c) deprotonation to give the phenolate. Phenoxides are enolates stabilised by aromaticity . Under normal circumstances, phenoxide is more reactive at the oxygen position, but the oxygen position is a "hard" nucleophile whereas the alpha-carbon positions tend to be "soft". Phenol

2200-433: The minimum lethal human dose was cited as 140 mg/kg. The Agency for Toxic Substances and Disease Registry (ATSDR), U.S. Department of Health and Human Services states the fatal dose for ingestion of phenol is from 1 to 32 g. Chemical burns from skin exposures can be decontaminated by washing with polyethylene glycol , isopropyl alcohol , or perhaps even copious amounts of water. Removal of contaminated clothing

2255-436: The mountain range a total length of over 500 kilometers, averaging about 1000 meters in height. Prominent peaks of the range include Mount Seoraksan (1,708 m), Mount Kumgangsan (1,638 m), Mount Taebaeksan (1,566.7 m) and Mount Odaesan (1,563 m). To the east, the mountain range falls steeply into the sea, but to the west, there are more gentle slopes. Many spurs stretch southwest. The most important rivers of South Korea,

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2310-469: The partial oxidation of cumene (isopropylbenzene) via the Hock rearrangement : Compared to most other processes, the cumene process uses mild conditions and inexpensive raw materials. For the process to be economical, both phenol and the acetone by-product must be in demand. In 2010, worldwide demand for acetone was approximately 6.7 million tonnes, 83 percent of which was satisfied with acetone produced by

2365-404: The pi system. An alternative explanation involves the sigma framework, postulating that the dominant effect is the induction from the more electronegative sp hybridised carbons ; the comparatively more powerful inductive withdrawal of electron density that is provided by the sp system compared to an sp system allows for great stabilization of the oxyanion. In support of the second explanation,

2420-439: The presence of phenol and 4-methylphenol during musth . It is also one of the chemical compounds found in castoreum . This compound is ingested from the plants the beaver eats. Phenol is a measurable component in the aroma and taste of the distinctive Islay scotch whisky , generally ~30 ppm , but it can be over 160ppm in the malted barley used to produce whisky . This amount is different from and presumably higher than

2475-709: The production of carbolic soap . Concentrated phenol liquids are used for permanent treatment of ingrown toe and finger nails, a procedure known as a chemical matrixectomy . The procedure was first described by Otto Boll in 1945. Since that time phenol has become the chemical of choice for chemical matrixectomies performed by podiatrists. Concentrated liquid phenol can be used topically as a local anesthetic for otology procedures, such as myringotomy and tympanotomy tube placement, as an alternative to general anesthesia or other local anesthetics. It also has hemostatic and antiseptic qualities that make it ideal for this use. Phenol spray, usually at 1.4% phenol as an active ingredient,

2530-419: The reaction of strong base with benzenesulfonic acid , proceeding by the reaction of hydroxide with sodium benzenesulfonate to give sodium phenoxide. Acidification of the latter gives phenol. The net conversion is: Chlorobenzene can be hydrolyzed to phenol using base ( Dow process ) or steam ( Raschig–Hooker process ): These methods suffer from the cost of the chlorobenzene and the need to dispose of

2585-573: The river's potential for navigation and commerce, operating a thriving trade in armor and weapons with neighboring countries, including Yamato period Japan. Through the Silla, Goryeo , and Joseon periods, the river continued to serve as a major transportation corridor in the Gyeongsang region. It was especially used for transporting inland fresh seafood, such as mackerel , which were salted and dried to prevent them from spoiling. The city of Andong

2640-931: The statue of the Bodhisattva of wisdom . It was built by Jajang , a Silla Dynasty monk. The "Dragon Spring" at the entrance of the temple is known as the highest spring in Korea. The 2018 Winter Olympics took place in Pyeongchang , Gangwon-do , located in the mountains. Taebaek is also a name of a poomsae that is performed by the 3rd Dan black belts in Tae Kwon Do. Taebaek is mostly practised in Southern South Korea. 38°13′N 128°11′E  /  38.217°N 128.183°E  / 38.217; 128.183 Phenol Phenol (also known as carbolic acid , phenolic acid , or benzenol )

2695-442: The wound, covered with a layer of tin foil, leaving them for four days. When he checked the wound, Lister was pleasantly surprised to find no signs of infection, just redness near the edges of the wound from mild burning by the carbolic acid. Reapplying fresh bandages with diluted carbolic acid, the boy was able to walk home after about six weeks of treatment. By 16 March 1867, when the first results of Lister's work were published in

2750-435: The wounds with a piece of rag or lint covered in phenol. The skin irritation caused by continual exposure to phenol eventually led to the introduction of aseptic (germ-free) techniques in surgery. Lister's work was inspired by the works and experiments of his contemporary Louis Pasteur in sterilizing various biological media. He theorized that if germs could be killed or prevented, no infection would occur. Lister reasoned that

2805-468: Was blown up on August 3, 1950, in an effort to prevent North Korean forces from advancing on Daegu . A large number of South Korean refugees were killed in the explosion. Although some North Korean forces did cross the Nakdong River in places, for the most part the river marked their furthest advance. The Nakdong River valley includes numerous floodplain wetlands, the most well-known of which are

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2860-535: Was introduced in the summer of 1865, there were only six deaths in forty cases. The mortality rate had dropped from almost 50 per cent to around 15 per cent. It was a remarkable achievement Phenol was the main ingredient of the "carbolic smoke ball," an ineffective device marketed in London in the 19th century as protection against influenza and other ailments, and the subject of the famous law case Carlill v Carbolic Smoke Ball Company . The toxic effect of phenol on

2915-480: Was leaked into the river from Doosan Electronics. There were two leaks, the first thirty tons on March 14, 1991 and the second 1.3 tons on April 22. The phenol ended up at a water processing facility used for drinking water in Daegu and began to smell after converting to chlorophenol when the water was sanitized with chlorine . Although all but the southernmost reaches of the Nakdonggang River have ceased to serve as

2970-565: Was more economical by injection of each victim with phenol. Phenol injections were given to thousands of people. Maximilian Kolbe was also murdered with a phenol injection after surviving two weeks of dehydration and starvation in Auschwitz when he volunteered to die in place of a stranger . Approximately one gram is sufficient to cause death. Phenol is a normal metabolic product, excreted in quantities up to 40 mg/L in human urine. The temporal gland secretion of male elephants showed

3025-629: Was the farthest inland the fish could be brought before going bad, so many people flocked there during the Joseon dynasty to eat fish. As a barrier to movement, the Nakdong River gained sudden prominence during the Korean War . The southern length of the river formed the western portion of the Pusan Perimeter , which the UN forces fought to maintain during the autumn of 1950. The bridge at Waegwan

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