Methyl methacrylate (MMA) ne mai muhimmanci Organic sinadaran albarkatun kasa da kuma polymer monomer, yafi amfani a samar da Organic gilashin, gyare-gyaren robobi, acrylics, coatings da Pharmaceutical polymer kayan, da dai sauransu Yana da wani high-karshen abu ga Aerospace, lantarki lantarki. bayanai, fiber optic, robotics da sauran fannoni.

A matsayin monomer na kayan abu, ana amfani da MMA galibi a cikin samar da polymethyl methacrylate (wanda aka fi sani da plexiglass, PMMA), kuma ana iya haɗa shi tare da wasu mahaɗan vinyl don samun samfuran da ke da kaddarorin daban-daban, kamar don kera polyvinyl chloride (PVC). ) Additives ACR, MBS da kuma matsayin na biyu monomer a cikin samar da acrylics.

A halin yanzu, akwai uku nau'i na balagagge matakai don samar da MMA a gida da kuma kasashen waje: methacrylamide hydrolysis esterification hanya (acetone cyanohydrin Hanyar da methacrylonitrile Hanyar), isobutylene hadawan abu da iskar shaka hanya (Mitsubishi tsari da Asahi Kasei tsari) da kuma ethylene carbonyl kira hanya (. Hanyar BASF da hanyar Lucite Alpha).

1. Methacrylamide hydrolysis esterification hanya
Wannan hanya ita ce hanyar samar da MMA na gargajiya, gami da hanyar acetone cyanohydrin da hanyar methacrylonitrile, duka bayan methacrylamide matsakaici hydrolysis, esterification kira na MMA.

(1) Hanyar cyanohydrin acetone (hanyar ACH)

Hanyar ACH, wacce Amurka Lucite ta fara haɓaka, ita ce farkon hanyar samar da masana'antu ta MMA, kuma ita ce babban tsarin samar da MMA a duniya a halin yanzu.Wannan hanyar tana amfani da acetone, hydrocyanic acid, sulfuric acid da methanol azaman albarkatun ƙasa, kuma matakan amsa sun haɗa da: amsawar cyanohydrinization, amsawar amidation da halayen esterification na hydrolysis.

Tsarin ACH ya balaga da fasaha, amma yana da babban lahani masu zuwa:

○ Yin amfani da acid hydrocyanic mai guba mai guba, wanda ke buƙatar tsauraran matakan kariya yayin ajiya, sufuri da amfani;

○ Ta hanyar samar da adadin acid mai yawa (maganin ruwa tare da sulfuric acid da ammonium bisulfate a matsayin manyan abubuwan da ke dauke da ƙananan kwayoyin halitta), adadin wanda shine sau 2.5 ~ 3.5 na MMA, kuma yana da tsanani. tushen gurbatar muhalli;

o Sakamakon amfani da sulfuric acid, ana buƙatar kayan aikin kariya, kuma aikin na'urar yana da tsada.

(2) Hanyar Methacrylonitrile (Hanyar MAN)

Asahi Kasei ya samar da tsarin methacrylonitrile (MAN) bisa hanyar ACH, watau isobutylene ko tert-butanol ya zama oxidized ta ammonia don samun MAN, wanda ke amsawa tare da sulfuric acid don samar da methacrylamide, wanda ya amsa tare da sulfuric acid da methanol don samar da shi. MMA.Hanyar MAN ta hada da ammonia oxidation reaction, amidation reaction da hydrolysis esterification dauki, kuma zai iya amfani da mafi yawan kayan aiki na ACH shuka.Halin hydrolysis yana amfani da sulfuric acid da yawa, kuma yawan amfanin matsakaicin methacrylamide ya kusan 100%.Koyaya, hanyar tana da samfuran hydrocyanic acid mai guba mai guba, hydrocyanic acid da sulfuric acid suna da lalacewa sosai, abubuwan da ake buƙata na kayan aiki suna da girma sosai, yayin da haɗarin muhalli suna da yawa.

2. isobutylene hadawan abu da iskar shaka hanya
Isobutylene oxidation ya kasance hanyar fasaha da aka fi so ga manyan kamfanoni a duniya saboda yawan ingancinsa da kare muhalli, amma matakin fasaha yana da girma, kuma Japan ce kawai ta taba samun fasahar a duniya kuma ta toshe fasahar zuwa China.Hanyar ta ƙunshi nau'ikan tsarin Mitsubishi guda biyu da tsarin Asahi Kasei.

(1) Tsarin Mitsubishi (hanyar isobutylene uku)

Mitsubishi Rayon na Japan ya ƙirƙira sabon tsari don samar da MMA daga isobutylene ko tert-butanol a matsayin albarkatun ƙasa, zaɓin oxidation mataki biyu ta iska don samun methacrylic acid (MAA), sa'an nan kuma an fitar da shi da methanol.Bayan haɓaka masana'antu na Mitsubishi Rayon, Kamfanin Japan Asahi Kasei, Japan Kyoto Monomer Company, Korea Lucky Company, da dai sauransu sun sami masana'antu daya bayan daya.Kamfanin na cikin gida na Shanghai Huayi Group Company ya zuba jari mai yawa na ɗan adam da albarkatun kuɗi, kuma bayan shekaru 15 na ci gaba da ƙoƙari na ƙarnuka biyu, ya sami nasarar ɓullo da kansa ta hanyar samar da iskar shaka mai tsafta na isobutylene fasahar MMA, kuma a cikin Disamba 2017 , ya kammala kuma ya fara aiki da wani kamfanin masana'antu na MMA mai nauyin ton 50,000 a kamfanin hadin gwiwarsa na Dongming Huayi Yuhuang da ke Heze na lardin Shandong, ya karya ikon mallakar fasaha na kasar Japan, ya zama kamfani daya tilo da ke da wannan fasaha a kasar Sin.fasaha, kuma ya sa kasar Sin ta zama kasa ta biyu da ke da fasahar masana'antu don samar da MAA da MMA ta hanyar iskar oxygen na isobutylene.

(2) Tsarin Asahi Kasei (tsari mai mataki biyu isobutylene)

Kamfanin Asahi Kasei na Japan ya dade yana jajircewa wajen samar da hanyar tantancewa kai tsaye don samar da MMA, wanda aka samu nasarar kerawa kuma aka fara aiki a shekarar 1999 tare da masana'antar masana'antu mai nauyin ton 60,000 a Kawasaki na kasar Japan, daga baya kuma ya fadada zuwa ton 100,000.Hanyar fasaha ta ƙunshi amsawar mataki biyu, watau iskar shaka na isobutylene ko tert-butanol a cikin yanayin iskar gas a ƙarƙashin aikin Mo-Bi composite oxide catalyst don samar da methacrolein (MAL), sannan kuma oxidative esterification na MAL a cikin ruwa lokaci a karkashin aikin Pd-Pb mai kara kuzari don samar da MMA kai tsaye, inda esterification oxidative na MAL shine babban mataki a wannan hanya don samar da MMA.Hanyar tsari na Asahi Kasei yana da sauƙi, tare da matakai biyu kawai na amsawa da ruwa kawai a matsayin samfurin samfurin, wanda yake da kore da kuma yanayin muhalli, amma zane da shirye-shiryen mai kara kuzari yana da matukar bukata.An ba da rahoton cewa an inganta aikin asahi Kasei oxidative esterification catalyst daga ƙarni na farko na Pd-Pb zuwa sabon ƙarni na Au-Ni catalyst.

Bayan da aka inganta fasahar Asahi Kasei daga shekarar 2003 zuwa 2008, cibiyoyin bincike na cikin gida sun fara samun bunkasuwar bincike a wannan fanni, inda aka mayar da hankali kan bangarori da dama kamar jami'ar Hebei Normal University, da Cibiyar Injiniya ta Process, Kwalejin Kimiyya ta kasar Sin, Jami'ar Tianjin da Jami'ar Harbin Engineering. Bayan shekarar 2015, an fara gudanar da bincike a cikin gida kan abubuwan da suka hada da Au-Ni, wanda wakilin Cibiyar Injiniya ta Dalian, Cibiyar Nazarin Kimiyya ta kasar Sin, ta samu babban ci gaba a fannin kimiyyar kere-kere na Pd-Pb da dai sauransu. kananan matukin jirgi binciken, kammala ingantawa na Nano-zinariya kara kuzari shiri tsari, dauki yanayin nunawa da kuma a tsaye hažaka dogon sake zagayowar aiki kimantawa gwajin, kuma yanzu rayayye hadin gwiwa tare da Enterprises don bunkasa masana'antu fasahar.

3. Ethylene carbonyl kira hanya
Fasahar ethylene carbonyl kirar hanyar masana'antu ta haɗa da tsarin BASF da tsarin ethylene-propionic acid methyl ester.

(1) Hanyar ethylene-propionic acid (tsarin BASF)

Tsarin ya ƙunshi matakai huɗu: ethylene an hydroformylated don samun propionaldehyde, propionaldehyde yana tashe tare da formaldehyde don samar da MAL, MAL iskar oxidized ne a cikin na'ura mai kayyade gado na tubular don samar da MAA, kuma MAA ya rabu kuma an tsarkake shi don samar da MMA ta hanyar esterification tare da methanol.Halin shine maɓalli mataki.Tsarin yana buƙatar matakai huɗu, wanda yake da ɗanɗano kaɗan kuma yana buƙatar kayan aiki masu yawa da tsadar saka hannun jari, yayin da fa'ida ita ce ƙarancin farashin albarkatun ƙasa.

Hakanan an sami ci gaban cikin gida a cikin haɓaka fasahar ethylene-propylene-formaldehyde na MMA.2017, Shanghai Huayi Group Company, tare da haɗin gwiwar Nanjing NOAO New Materials Company da Tianjin University, kammala wani matukin jirgi na 1,000 ton na propylene-formaldehyde condensation tare da formaldehyde zuwa methacrolein da kuma ci gaban wani tsari kunshin na 90,000-ton masana'antu shuka.Bugu da kari, Cibiyar Injiniya Tsari ta Kwalejin Kimiyya ta kasar Sin, tare da hadin gwiwar kungiyar Henan Energy da Chemical Group, sun kammala aikin gwajin gwajin masana'antu mai nauyin ton 1,000, tare da samun nasarar samun kwanciyar hankali a shekarar 2018.

(2) Tsarin Ethylene-methyl propionate (Tsarin Lucite Alpha)

Yanayin aiki na Lucite Alpha yana da sauƙi, yawan amfanin ƙasa yana da girma, zuba jari na shuka da farashin albarkatun ƙasa ba su da ƙasa, kuma ma'auni na ɗayan ɗaya yana da sauƙin yin babban, a halin yanzu Lucite kawai yana da iko na musamman na wannan fasaha a duniya kuma ba haka ba ne. canjawa wuri zuwa waje duniya.

An rarraba tsarin Alpha zuwa matakai biyu:

Mataki na farko shine amsawar ethylene tare da CO da methanol don samar da methyl propionate

ta yin amfani da palladium-based homogeneous carbonylation mai kara kuzari, wanda yana da halaye na babban aiki, high selectivity (99.9%) da kuma dogon sabis rayuwa, da kuma dauki da za'ayi a karkashin m yanayi, wanda shi ne kasa lalata da na'urar da kuma rage ginin babban birnin kasar zuba jari. ;

Mataki na biyu shine amsawar methyl propionate tare da formaldehyde don samar da MMA

Ana amfani da mai kara kuzari mai yawa, wanda ke da babban zaɓi na MMA.A cikin 'yan shekarun nan, kamfanoni na cikin gida sun ba da babbar sha'awa a cikin ci gaban fasaha na methyl propionate da formaldehyde condensation zuwa MMA, kuma sun sami babban ci gaba a cikin haɓakawa da haɓakar tsarin amsawar gadaje, amma rayuwar mai kara kuzari ba ta kai ga buƙatun masana'antu ba. aikace-aikace.