The manipulation of phosphorus penttoxide

Abstract

July 15, 1Od2 ' CHEMISTRY AND INDUSTRY 000'werc nbIc to i1istingiiisIi four typcs of peptization or colloidnl dissolut~ion : (1) ndsorption pcptizntion (carbon and picric nciil) ; (2) dissolution pcptizntion (mctnl hyclrosidcs nnd ncitls) ; (3) pcptizntion through smelling (gelnt,in in wntcr) ; (4) spontnncous colloidnl tlissoliition (dycs nnil sonps in wit,cr, ccllulosc ncet.ntc in chloroform). Adsorptioniiiicl dissoliitioii-pcptizntioii arc chnrnctcrized hy n n optinirim for inccliiini nmounts of solid phase, which is not obsorvetl ns ii riilc in tlic rcmnining two metliods of dissolution, whore tho ciirve iisiinlly rises stenclily. Tlic pcptizrition of strinnic ncitl by liydrocliloric iiciil, zinc liytlrositlc by soiliiim Iiydrositle, nntl bismuth liyilrosidc by lactose or sucrose fiirnishcd results in nccorclance with thc solid-phase rule, but csceptions nppcrirctl in blic systems zinc hyyilroxidc-liytlrocliloric ncitl and zinc liydrositlc-ncetic ncid, in wlJcli cnscs tlic solubility is indcpcntlcnt of the iirnoiint of tlic solid phrisc. It, is ~~r011ril~Ic t l i n t piircly clicniicnl reaction is mriitily conccrnctl in tlic csccptioii:il cnscs, diilst tlic solid-plinsc rirle epplios to tlic systciiis in\~ol\~ing the opcrntion cliiclly of colloitl-clicmicn1 proccsscs.The rclat ions I)ctwcc!n colloicl:il soliil)ilit~y riiitl inolcciilnr solul~ility linvc bccn clisc~~sscd I J~ .Jcrniolenko,lz who lins cst.alilislict1 t,hc vnliditey of tho solid-pliiisc rille in tho dissolution of copper c:irl)onntc hy rimnioiiiii in t,lic prcscncc of niniiionirini cliloriclc.I hc s~velling of gels lins rilso bccn found to cscniplify thc solid-plinse rulc. Ostivnltl nntl Ktililcr*z ol).wrvetl that tlic relntivc sivclling of gelritin in m t e r frills ns tho rirtio of t,lic solid plinse to the liquid is increnscd. Thc spont:incous tlissoliition of gelritin in writer rilso iiicrcnscs ris tlic ;mount; of gclntin is increnscd. 'l'ho obscrvat,ion that3 tlic inflricnco of t h solid plinsc oil I)pth tlicse proccsscs is niiirkcilly less a t lower tcmpcriiturcs has consitlcrrrblc significnncc. hcoriling to Lloytl,'J the influciicc of tlic volume of liqiiitl on t h s\vclling of conimcrci:il gcliitiii is tlirc to tlm cliniigcs i n tlic rclative coi~ccnt~rntion of clectrolytcs ;tiid ilcgrndntion products of gclritin ~~rcscnt~ as in~piiritics. 'l'lic vnriation of the rlcgrce of s\vclling in sodiiiui hydroside solutions with the voliinic of tho solution is nttrildxd to hydrolytic decoinposition of tlic gcliitin. Wlicn piire gcltitin swclls ti12 CHEXISTHY AND LVDUSTRY Jitly 15, 1032