Soda caustic(NaOH) bụ otu n'ime ihe ndị kacha mkpa e ji emepụta nri kemịkalụ, nke a na-emepụta kwa afọ nke 106t. A na-eji NaOH eme ihe na kemịkalụ organic, na mmepụta aluminom, na ụlọ ọrụ akwụkwọ, na ụlọ ọrụ nhazi nri, na mmepụta ihe nhicha, wdg. Caustic soda bụ ngwaahịa so na mmepụta chlorine, nke 97% na-eme site na electrolysis nke sodium chloride.
Soda caustic nwere mmetụta dị ike n'ọtụtụ ihe ndị e ji ígwè rụọ, ọkachasị n'oge okpomọkụ na oke okpomọkụ. A maara ya kemgbe ogologo oge na nickel na-eguzogide nchara dị mma na soda caustic na oke okpomọkụ na oke okpomọkụ niile, dịka Foto 1 si gosi. Na mgbakwunye, ewezuga na oke okpomọkụ na oke okpomọkụ, nickel anaghị enwe ike ịgbawa nrụgide-corrosion nke caustic kpatara. Ya mere, a na-eji usoro nickel ọkọlọtọ alloy 200 (EN 2.4066/UNS N02200) na alloy 201 (EN 2.4068/UNS N02201) eme ihe n'oge ndị a nke mmepụta soda caustic, nke chọrọ oke iguzogide nchara kachasị elu. E jikwa mpempe nickel mee ka cathodes dị na sel electrolysis ejiri mee ihe na usoro membrane. E jikwa nickel mee nkeji ndị dị n'okpuru maka itinye mmanya ahụ n'ọrụ. Ha na-arụ ọrụ dịka ụkpụrụ mwepụ ọtụtụ ọkwa si dị, ọkachasị na ndị na-ekupụ ihe nkiri na-ada ada. N'ime nkeji ndị a, a na-eji nickel eme ihe n'ụdị tubes ma ọ bụ mpempe akwụkwọ tube maka ihe mgbanwe okpomọkụ tupu evaporation, dị ka mpempe akwụkwọ ma ọ bụ efere mkpuchi maka nkeji tupu evaporation, na na paịpụ maka ibuga ihe ngwọta soda caustic. Dabere na ọnụego mmiri, kristal soda caustic (mgwọta zuru oke) nwere ike ibute mbuze na tubes mgbanwe okpomọkụ, nke na-eme ka ọ dị mkpa ịgbanwe ha mgbe oge ọrụ nke afọ 2-5 gasịrị. A na-eji usoro evaporator ọdịda-film emepụta soda caustic nke nwere nnukwu ihe, nke na-anaghị agbaze mmiri. N'usoro ihe nkiri ọdịda nke Bertrams mepụtara, a na-eji nnu agbaze na okpomọkụ nke ihe dị ka 400 °C dị ka ihe na-ekpo ọkụ. N'ebe a, a ga-eji ọkpọkọ e ji obere carbon nickel alloy 201 (EN 2.4068/UNS N02201) mee ihe n'ihi na n'oge okpomọkụ karịrị ihe dị ka 315 °C (600 °F), ọdịnaya carbon dị elu nke nickel ọkwa alloy 200 (EN 2.4066/UNS N02200) nwere ike ibute mmiri ozuzo graphite na ókèala ọka.
Nickel bụ ihe a na-ahọrọ maka ihe owuwu maka ihe na-ekupụ mmiri soda caustic ebe a naghị eji ígwè austenitic eme ihe. N'ọnọdụ adịghị ọcha dịka chlorates ma ọ bụ sọlfọ - ma ọ bụ mgbe achọrọ ike dị elu - a na-eji ihe ndị nwere chromium dị ka alloy 600 L (EN 2.4817/UNS N06600) eme ihe n'ọnọdụ ụfọdụ. Ihe ọzọ na-adọrọ mmasị maka gburugburu caustic bụ nnukwu chromium nwere alloy 33 (EN 1.4591/UNS R20033). Ọ bụrụ na a ga-eji ihe ndị a, a ga-ahụ na ọnọdụ ọrụ agaghị ebute mgbawa nrụgide-corrosion.
Alloy 33 (EN 1.4591/UNS R20033) na-egosipụta ezigbo nguzogide nchara na 25 na 50% NaOH ruo ebe esi mmiri na 70% NaOH na 170 °C. Alloy a gosikwara arụmọrụ dị mma na nnwale ubi n'ime osisi e tinyere na soda caustic site na usoro diaphragm.39 Foto 21 na-egosi ụfọdụ nsonaazụ gbasara njupụta nke mmanya caustic diaphragm a, nke e merụrụ na chlorides na chlorates. Ruo njupụta nke 45% NaOH, ihe alloy 33 (EN 1.4591/UNS R20033) na nickel alloy 201 (EN 2.4068/UNS N2201) na-egosi nguzogide pụrụ iche yiri ya. Site na mmụba okpomọkụ na njupụta alloy 33 na-aghọ ihe na-eguzogide karịa nickel. Ya mere, n'ihi nnukwu ọdịnaya chromium ya 33 yiri ka ọ bara uru ijikwa ngwọta caustic na chlorides na hypochlorite site na usoro diaphragm ma ọ bụ mercury cell.
Oge ozi: Disemba-21-2022