उत्प्रेरण  हिन्दी देवनागरी में पढ़ें।

utpreran (angrezi: Catalysis) se tatpary hai ki "jab kisi rasayanik abhikriya ki gati kisi padarth ki upasthiti matr se badh jati hai to ise 'utpreran' kahate hain." jabaki abhikriya ki gati badhane vale padarth ko 'utprerak' (catalyst) kahate hain. audyogik roop se mahattvapoorn rasayanon ke nirman men utprerakon ki bahut badi bhoomika hai, kyonki inake prayog se abhikriya ki gati badh jati hai, jisase anek prakar se arthik labh hota hai aur utpadan bhi adhik tezi se ho pata hai. utpreran ki mukhy visheshataen nimnalikhit hain:

  1. kriya ke ant men utprerak aparivartit bach rahata hai. usake bhautik sngathan men chahe jo parivartan ho jaen, parntu usake rasayanik sngathan men koee antar nahin hota.
  1. utprerak padarth ki keval thodi matra hi paryapt hoti hai. utprerak ki yah visheshata is tathy par nirbhar hai ki vah kriya ke ant men aparivartit rahata hai. parntu kuchh aisi kriyaon men, jinamen utprerak ek madhyamik asthayi yaugik banata hai, utprerak ki adhik matra ki avashyakata hoti hai.
  1. utprerak utkramaniy pratikriyaon men pratyaksh aur viparit donon or ki kriyaon ko barabar utprerit karata hai at: utprerak ki upasthiti se pratikriya ki samy sthiti men koee parivartan nahin hota, keval samyasthapan ke samay men hi antar ho jata hai.
  1. utprerak nee kriya ko prarnbh kar sakata hai. yadyapi ostavald ne sarvapratham yah mat pragat kiya tha ki utprerak nee kriya prarnbh nahin kar sakata, to bhi adhunik vaigyanikon ka yah mat hai ki utprarek nee kriya ko bhi prarnbh kar sakata hai.
  1. pratyek rasayanik kriya men kuchh vishisht utprerak hi kary kar sakate hain. abhi tak vaigyanikon ke lie yah snbhav nahin ho saka hai ki ve sabhi rasayanik kriyaon ke lie kisi ek hi utprerak ko kam men laen. yah avashyak nahin ki kisi ek kriya ka utprerak kisi doosari kriya ko bhi utprerit kare.

utpreran ke prakar

sabhi utprerit kriyaon ko do bhagon men vibhajit kiya ja sakata hai-

  1. samavayavi utprerit kriyaen (samavayavi utpreran)
  2. vishamavayavi utprerit kriyaen (vishamavayavi utpreran)

samavayavi utpreran

is prakar ki kriyaon men utprerak, pratikarmak tatha pratiphal sabhi ek hi avastha men upasthit hote hain. jaise- salfyoorik aml banane ki veshm vidhi men salphar daiaauksaid, bhap tatha aauksijan ke snyog se salfyoorik aml banata hai tatha naitrik aauksaid dvara yah kriya utprerit hoti hai. is kriya men pratikarmak, utprerak tatha pratiphal isi gaisiy avastha men rahate hain.

vishamavayavi utpreran

is prakar ki kriyaon men utprerak, pratikarmak tatha pratiphal vibhinn avasthaon men upasthit rahate hain. jaise- amoniya banane ki habar-vidhi men naitrojan tatha haidrojan ki snyog kriya ko ferik aauksaid utprerit karata hai. sookshm nikil ki upasthiti men vanaspatik telon ka haidrojanikaran is prakar ki kriyaon ka ek any udaharan hai.

  • kuchh padarth apani upasthiti se rasayanik kriya ke veg par prabhav nahin dalate, parntu kuchh doosare utprerakon ki kriya ko prabhavit karate hain. inamen se un padartho ki, jo utprerakon ki kriyashilata ko badha dete hain, utprerak vardhak tatha un padartho ko, jo utprerakon ki kriyashilata kam kar dete hain, utprerak virodhi ya utprerak vish kahate hain.

atm utprerak:- kuchh pratikriyaen aisi bhi gyat hain jinamen pratikraya se hi utpann koee padarth pratikriya ke lie utprerak ka kary karata hai. udaharanarth, ethil aisitet ke jalavichchhedan men jo aisitik aml prapt hota hai, vahi estar ke jal vichchhedan ki kriya ko utprerit karata hai.

utpreran ke siddhant:- yadyapi utpreran ko samajhane samajhane ke lie bahut pahale se adhyayan hote chale a rahe hain, tathapi is vishay men abhi antim nishkarsh nahin nikala hai. vaigyanik isapar ekamat hain ki sabhi utprerak ek hi siddhant ke anusar kriya nahin karate . utpreran ki vyavastha ke lie do siddhant kam men lae jate hain:-

  1. madhyavarti yaugik siddhant
  2. adhishoshan siddhant.

madhyavarti yaugik siddhant

yah utpreran ki vyakhya ke lie ek rasayanik siddhant hai. isake anusar utprerak pahale pratikarmakon men se ek ke sath kriya karake ek madhyavarti asthayi yaugik banata hai; phir vah madhyavarti asthayi yaugik doosare pratikarmakon se kriya karake pratiphal deta hai tatha utprerak pun: apani poorvavastha men a jata hai. isake anusar pratikarmakon 'k' tatha 'kh' ki snyojan kriya utprerak 'g' ki upasthiti men nimnalikhit prakar se prakat ki jati hai:

k + g = k g (asthayi madhyavarti yaugik);

k g + kh = k kh + g;

k + g = k g.

kriya ke ant tak yahi kram chalata rahata hai.

madhyavarti yaugik siddhant ke dvara kuchh kriyaon ke utpreran ki vyakhya saral hai. parntu adhikansh vishamavayavi kriyaon tatha utprerak vardhakon athava vishon ki kriyaon ko samajhana kathin ya asnbhav sa hai.

adhishoshan siddhant

yah utpreran ki vyakhya ke lie bhautik siddhant hai. is siddhant ke anusar pratikarmak utprerak ke tal par ghanibhoot ho jate hain. is prakar utprerak tal par pratikarmakon ki sandrata badh jane se matra-anupati-niyam ke anusar kriya ka veg badh jata hai.

ab uparyukt donon siddhanton ko milakar ek naya siddhant pratipadit kiya gaya hai. isake anusar utprerak padarth ke tal par kuchh sakriy kendr hote hain. in kendron men anuon ya paramanuon ko adhishoshit karane ki kshamata hoti hai. at: dhatu ke tal par pratikarmakon ke ghani bhoot hone se sadrnta to badhati hi hai, jisake karan kriyaveg men vriddhi hoti hai, sath hi in sakriy kendron par pratikarmak inake sath asthayi yaugik bhi bana lete hain, jo madhyavarti yaugik siddhant ke anusar utpreran ka kary karate hain.

enzaimon dvara utpreran-enjaim jatil karbanik padarth hote hain jo paudhon ya praniyon se prapt kie jate hain. ye adhikansh pratikriyaon men atyutm utprerak siddh hue hain. ped paudhon men hone vali lagabhag sabhi kriyaon men enjaim utprerak ka kary karate hain. isake atirikt hamare sharir men honevali kriyaon, visheshata bhojan ke pachan men bhi enjaim utpreerak ka kam karate hain.

upayog

audyogik tatha rasayanik kriyakshetr men utprerak bahut hi upayogi siddh hue hain. naitrojan ka sthirikaran utprerit kriyao ka ek sadharan udaharan hai. ped paudhon ke lie sthayi naitrojan ki upalabdhi naitret ya amoniya ke roop men hoti hai. naitrojan ke ye donon hi roop utprerako ki sahayata se nirmit hote rahate hain.[1]

dvitiy mahayuddh ke samay lagabhag samast vishv men motar adi vahanon ko chalane men jo eendhan kam men laya jata tha vah sab utprerakon ki sahayata se hi taiyar kiya jata tha. utpreran dvara petroliyam se bahut se aise padarth banae jate the jo eendhan ke roop men kam men lae jate the. isake atirikt utprerit kriyaon ka any mahatv bhi hai, udaharanat: byootadaeen tatha staeerin se snshlisht rabar banane, gndhakaml ke nirman, tatha sookshm khndit nikal ki upasthiti men vanaspatik telon ke haidrojanikaran dvara vanaspati ghi ke nirman men, ityadi.[2]



panne ki pragati avastha
adhar
prarambhik
madhyamik
poornata
shodh

tika tippani aur sndarbh

  1. hindi vishvakosh, khand 2 |prakashak: nagari pracharini sabha, varanasi |snkalan: bharat diskavari pustakalay |prishth snkhya: 85 |
  2. sn.grn.-glastan : tekst buk aauv phizikal kemistri; aidavantej in kaitailisis; meharotra; ar.si. : bhautik rasayan ki roop rekha.

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