Water temporary poison

Moreover, the kinetics are further complicated by the high level of water in the reactor inlet, deriving from its high concentration in both fresh and recycled ethanol, that acts as a temporary poison for the catalyst and strongly reduces the reaction rate [6]. 

In the case of gaseous catalyst poisons, a distinction can be made between permanent poisons causing an irreversible loss of catalytic activity and temporary poisons which lower the activity only while present in the synthesis gas. This distinction is fully discussed in the book by Nielsen. Permanent poisons such as sulfur accumulate upon the catalyst surface and may be detected by chemical and spectroscopic analysis, while temporary poisons do not interact nearly as strongly with the catalyst. It is very difficult to detect temporary poisons by means of post-analytical methods. The principal temporary poisons are oxygen, carbon oxides, and water. Since the catalyst also contains percent amounts of oxygen... 

The renal toxins of A. smithiana are identified as allenic norleucine and chlorocrotylglycine [102]. Poisoning with A. smithiana which were mistaken for the edible Tricholoma magnivelare (edible pine mushroom or matsutake) was reported in three Asian patients in the Pacific Northwest and two patients in Taiwan [103,104]. Nausea, vomiting, water diarrhea and abdominal discomfort without liver injury developed 4-11 hours post ingestion. Renal failure occurred 2 to 4 days later and temporary required hemodialysis. After several weeks, renal function recovered to the basehne level [104]. 

Properties Colorless cryst. very sol. in water sol. in ethanol insol. in diethyl ether m.w. 84.12 dens. 1.91 m.p. 167 C b.p. dec. pH pract. neutral Toxicology LD50 (IV, mouse) 95 mg/kg poison by IV route very low oral toxicity ing. unlikely, but large doses may cause mouth and esophageal irritation, stomach pain, cramps, vomiting, and collapse may cause minor, reversible effects on lungs high cones, of dust can cause upper respiratory tract irritation sol ns. may cause skin and eye irritation dust can cause mild, temporary eye pain TSCA listed... 

Properties Orthorhombic need., odorless, intense bitter taste sol. 1 g/1900 ml water, 0.8 ml alcohol, 80 ml benzene, 1.2 ml chloroform, 20 ml glycerol, 1900 ml of 10% ammonia water almost insol. in petroleum ether m.w. 324.43 m.p. 175 C (dec.) Toxicology LDLo (oral, rat) 800 mg/kg, (subcut., rat) 200 mg/kg, (IP, rat) 115 mg/kg, (IV, rabbit) 70 mg/kg poison by subcut., IV, IP, intramuscular routes mod. toxic by ing. human poison skin and mucous membrane irritant ing. of pure substance adversely affects eyes can cause temporary loss of vision human systemic effects by ing. (tinnitus, nausea, vomiting) experimental teratogen, reproductive effects human teratogenic effects mutagenic data TSCA listed... 

Not surprisingly, lead levels like these made many people sick and resulted in multiple adult deaths. Of the 404 cases of water-related lead poisoning documented by Bacup s health officer, 21 suffered from wristdrop 197 from headaches a few from spastic paralysis 206 from abdominal colic 148 from anemia several from insomnia and 339 exhibited the blue gum line. In 71 cases there was no patellar tendon reflex —that is, no knee-jerk in response to stimulation. Vision problems were not uncommon, including three cases of temporary blindness that lasted from a few minutes to a few days. Vertigo was also not uncommon while a sense of heat and burning in the soles of the feet was rare but not unheard of. In nearly every case the perspiration was lessened. In 148 cases, obstinate constipation was present and the faeces were hard and dry, and showed deficiency of bile. A forerunner of saturnine nephritis, albuminuria occurred in many individuals. Shooting pains in the hands, arms, back, and legs were very common, and usually mistaken for muscular rheumatism. ... 

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