Abstract: Provided are a sulfuric acid adding facility and an operation method therefor which enable an increase in the maximum capacity and the operation rate of a sulfuric acid supply pump provided in the sulfuric acid adding facility. In a sulfuric acid adding facility, sulfuric acid is added to an autoclave used in a leaching step of a high pressure acid leaching method for a nickel oxide ore. The sulfuric acid adding facility is provided with the same number (n+1) (n is an integer, at least 1) of each of the following: a plurality of sulfuric acid adding pipes for adding sulfuric acid into the autoclave; and a plurality of sulfuric acid supply pumps for supplying sulfuric acid to the sulfuric acid adding pipes. Each of the first through n+1th sulfuric acid supply pumps includes at least three diaphragms and discharge ports of the same number as that of the diaphragms.

Abstract: Provided are a sulfuric acid adding facility and an operation method therefor which enable an increase in the maximum capacity and the operation rate of a sulfuric acid supply pump provided in the sulfuric acid adding facility. In a sulfuric acid adding facility, sulfuric acid is added to an autoclave used in a leaching step of a high pressure acid leaching (HPAL) method for a nickel oxide ore. The sulfuric acid adding facility is provided with the same number (n+1) (n is an integer, at least 1) of each of the following: a plurality of sulfuric acid adding pipes for adding sulfuric acid into the autoclave; and a plurality of sulfuric acid supply pumps for supplying sulfuric acid to the sulfuric acid adding pipes. Each of the first through n+1th sulfuric acid supply pumps includes at least three diaphragms and discharge ports of the same number as that of the diaphragms.

Abstract: A slurry-transporting facility equipped with a plurality of pump-equipment circuits, whereby a stop of slurry supply to a transport destination at the time of switchover between the pump-equipment circuits for use is prevented to make an efficient operation possible. The slurry-transporting facility includes: pipe arrangements which branch out from a feed tank into the plurality of circuits; a transport pump provided in each of the pipe arrangement; a first valve provided upstream from the transport pump; a second valve provided downstream from the transport pump; and a uniting pipe arrangement formed by joining of the pipe arrangements at a predetermined position and connected to a LT heater. The uniting pipe arrangement is provided with a third valve configured to control the transportation of ore slurry to the LT heater and a pressure gauge configured to measure a pressure in the uniting pipe arrangement.

Abstract: A slurry-transporting facility equipped with a plurality of pump-equipment circuits, whereby a stop of slurry supply to a transport destination at the time of switchover between the pump-equipment circuits for use is prevented to make an efficient operation possible. The slurry-transporting facility includes: pipe arrangements which branch out from a feed tank into the plurality of circuits; a transport pump provided in each of the pipe arrangement; a first valve provided upstream from the transport pump; a second valve provided downstream from the transport pump; and a uniting pipe arrangement formed by joining of the pipe arrangements at a predetermined position and connected to a LT heater. The uniting pipe arrangement is provided with a third valve configured to control the transportation of ore slurry to the LT heater and a pressure gauge configured to measure a pressure in the uniting pipe arrangement.

Abstract: A nitrile having formula (2): RC≡N  (2) wherein R represents a substituted or unsubstituted alkyl, alkenyl, aralkyl or aryl group having 3 to 20 carbon atoms, is produced by a process, which comprises heating an aldoxime having formula (1): RCH═NOH  (1) wherein R is as defined above, at 80 to 250° C. in the presence of a catalyst (A) of an alkali metal or alkaline earth metal salt of a saturated or unsaturated mono- or dicarboxylic acid having 2 to 20 carbon atoms while removing product water from the reaction system by distillation.

Abstract: High-purity isochroman compounds can be obtained in high yields according to a simple and economical process for preparing isochroman compounds, comprising the step of adding an aquesous solution of formaldehyde having a concentration of 40 to 70 wt. % to a complex of an arylalkanol represented by the following general formula (II) with a Friedel-Crafts catalyst to cyclize the arylalkanol: ##STR1## wherein R.sub.1 and R.sub.2 each stands for a hydrogen atom, a lower alkyl group or a lower alkoxyl group, or alternatively R.sub.1 and R.sub.2 are respectively bonded to adjacent carbon atoms with mutual bonding of R.sub.1 and R.sub.2 together with the carbon atoms respectively bonded to R.sub.1 and R.sub.2 to form a benzene ring, a naphthalene ring, or a C.sub.5 or C.sub.6 cycloalkane or cycloalkene which may have 1 to 6 lower alkyl groups; and R.sub.3 stands for a hydrogen atom or a lower alkyl group.

Abstract: The present invention provides a process for producing a nitrile represented by the general formula (1):RC.ident.N (1)wherein R is alkyl, alkenyl, aralkyl or aryl, each may have a substituent, characterized by heating an aldoxime represented by the general formula (2):RCH.dbd.NOH (2)wherein R is as defined above, in the presence of one or more catalysts selected from hydroxides of alkali metals, alcoholates of alkali metals, hydroxides of alkaline earth metals and alcoholates of alkaline earth metals, and distilling off water formed in the course of the reaction from the reaction system. The process according to the present invention can produce a nitrile which is useful as a perfume or as a starting material for the organic synthesis of perfumes, medicines and so on in high yields and advantageously from the viewpoint of production economy.

Abstract: The present invention provides a process for producing a nitrile represented by the general formula (1):RC.ident.N (1)wherein R is alkyl, alkenyl, aralkyl or aryl, each may have a substituent, characterized by heating an aldoxime represented by the general formula (2):RCH=NOH (2)wherein R is as defined above, in the presence of one or more catalysts selected from hydroxides of alkali metals, alcoholates of alkali metals, hydroxides of alkaline earth metals and alcoholates of alkaline earth metals, and distilling off water formed in the course of the reaction from the reaction system. The process according to the present invention can produce a nitrile which is useful as a perfume or as a starting material for the organic synthesis of perfumes, medicines and so on in high yields and advantageously from the viewpoint of production economy.