Ke Kaʻina Hana Hana a me ka holomua ʻenehana o Sodium Cyanide

ʻO ka sodium cyanide (NaCN) he mea koʻikoʻi koʻikoʻi kumu kemika, i hoʻohana nui ʻia i nā māla e like me ka ʻili ʻana o ka mine gula, electroplating, a me ka synthesis o nā mea waena lāʻau. Kona Ka Hana Hana ua hala ma mua o hoʻokahi haneli mau makahiki o ka ʻenehana ʻenehana, a i kēia manawa, ua hoʻokumu ʻia kahi ʻōnaehana ʻoihana i hoʻomalu ʻia e ke ʻano synthesis. E hoʻokaʻawale pono kēia ʻatikala i nā kaʻina hana nui o ʻO ka sodium Cyanide a me kā lākou holomua ʻenehana, a kūkākūkā i nā kuhikuhi hoʻomohala e hiki mai ana.

I. Evolution of Sodium Cyanide Production Processes

1. Nā Kaʻina Hana Mua (Late 19th Century - Mid-20th Century)

I nā lā mua, ka hana ʻana o ka sodium cyanide hilinaʻi nui i ka unuhi ʻana mai nā kumuwaiwai kūlohelohe. No ka laʻana, ka "cyanidation process for gold extraction" invented in 1887 extracted cyanides ma ka hana ʻana i nā mea kanu cyanide (e like me nā ʻalemona ʻawaʻawa). Eia naʻe, ʻaʻole kūpono kēia ʻano hana, ke kumu kūʻai, a paʻakikī hoʻi e hoʻokō i nā pono o ka ʻoihana. I ka hoʻomaka ʻana o ke kenekulia 20, ua hoʻomohala ka loea Kelemania ʻo Friedrich Kahlbaum i ke ʻano hoʻoheheʻe cyanide, nāna i hoʻomākaukau. ʻO Sodium cyanide ma ka hana ʻana i ka calcium cyanide me ka sodium carbonate. Ma muli o ke kumukūʻai haʻahaʻa o nā mea maka a me ka maʻalahi o ke kaʻina hana, ua lilo kēia kaʻina i ka ʻenehana nui i nā lā mua.

2. Ka Piʻi ʻana o ke ʻano Synthesis (Mid-20th Century a hiki i kēia manawa)

Me ka hoʻomohala ʻana o ka ʻoihana petrochemical, ua hoʻololi mālie ke ʻano synthesis i nā kaʻina hana kuʻuna. I kēia manawa, ʻoi aku ma mua o 90% o ka sodium cyanide ma ka honua holoʻokoʻa i hana ʻia me ka hoʻohana ʻana i nā kaʻina hana synthesis ʻekolu:

• Kaʻina Andrussow

Me ka hoʻohana ʻana i ka methane, ammonia, a me ka oxygen ma ke ʻano he mea maka, e hana ʻia kahi hopena oxidation ma lalo o ka hana a ka platinum-rhodium alloy catalyst:

Hoʻopili ʻia ke kinoea hydrogen cyanide (HCN) i hana ʻia e ka sodium hydroxide e loaʻa ai kahi hopena sodium cyanide. Loaʻa i kēia kaʻina nā mea maikaʻi o nā kumu waiwai haʻahaʻa haʻahaʻa a me ka wikiwiki o ka hopena, akā ʻo ke kiʻekiʻe kiʻekiʻe (1000 - 1200 ° C) a me ka hoʻohana ʻana i nā mea hoʻoheheʻe metala makamae ka hopena i nā kumukūʻai kiʻekiʻe.

• ʻO ke ʻano Pyrolysis Aila Māmā

Ke hoʻohana nei i ka aila māmā (e like me ka naphtha) e like me ka mea maka, hana ʻia ʻo HCN ma o ka pyrolysis ma kahi wela kiʻekiʻe (1400 - 1500 ° C), a ua like ka mālama ʻana ma hope me ke kaʻina hana Andrussow. He kūpono kēia kaʻina hana no ka hana nui akā he kiʻekiʻe loa ka hoʻohana ʻana i ka ikehu a hoʻopuka i ka nui o ke kalapona ʻeleʻele e like me ka huahana.

• Methanol Ammonia Oxidation Method

Me ka hoʻohana ʻana i ka methanol, ammonia, a me ka ea ma ke ʻano he mea maka, hana ʻia ka HCN ma lalo o ka hana a kahi catalyst (e like me V₂O₅-MoO₃):

ʻO kēia kaʻina hana he haʻahaʻa haʻahaʻa haʻahaʻa a me nā kūlana hoʻonā haʻahaʻa (400 - 500°C), a ua lilo ia i mea koho maikaʻi loa no nā mana hana hou.

II. ʻO ka holomua ʻenehana a me nā kuhikuhi hou

1. Hoʻomohala ʻana i nā kaʻina hana ʻōmaʻomaʻo

Loaʻa i nā kaʻina hana kuʻuna nā pilikia o ka hoʻohana ʻana i ka ikehu kiʻekiʻe a me ka pollution kiʻekiʻe. I nā makahiki i hala iho nei, ua ʻimi nā mea noiʻi i nā ʻenehana ʻōmaʻomaʻo penei:

• Keʻano Biosynthesis

Ke hoʻohana nei i nā microorganisms (e like me Pseudomonas) e hoʻopaʻa i ka hydrolysis o nā pūhui nitrile e hana ai. Cyanides, akā, aia nō ia ma ke kahua hoʻokolohua.

• Electrochemical Synthesis

ʻO ka hana hou ʻana i ka sodium cyanide ma o ka hoʻoheheʻe ʻana i ka wai ʻino i loko o ka cyanide no ka hoʻokō ʻana i nā kumuwaiwai, akā pono e hoʻomaikaʻi hou ʻia ka pono a me ke kumukūʻai.

2. Nā ʻenehana hoʻomalu a me ka palekana

ʻO ka hana ʻana o ka sodium cyanide e pili ana i nā mea ʻawaʻawa, a he mea nui ka mālama palekana. Hoʻohana maʻamau nā hale hana hou i kahi Distributed Control System (DCS) e hoʻokō pono i ka nānā ʻana i ke kaʻina holoʻokoʻa, a hoʻolauna i ka ʻenehana loiloi spectral pūnaewele e nānā i ka ʻike HCN i ka manawa maoli, e hōʻemi ana i ka hopena o ka leakage.

3. Ke Ana Ho'okele Waiwai Po'ai

E hoʻomaikaʻi i ka hoʻohana ʻana i nā kumuwaiwai ma o nā ʻenehana hana hui. No ka laʻana, hiki ke hoʻohana ʻia ke kalapona kalapona i hana ʻia ma ke kaʻina hana Andrussow no ka hana ʻana i ka urea, a me ke kalapona ʻeleʻele i hana ʻia ma ka ʻO ke ʻano Pyrolysis Aila Māmā hiki ke hoʻohana ʻia ma ke ʻano he lāʻau hoʻoikaika kino, e hana ana i kahi kaulahao ʻoihana paʻa o "nā kumuwaiwai - nā huahana - nā ʻōpala - nā kumuwaiwai hou".

III. Nā Luʻi a me nā ʻano o ka wā e hiki mai ana

1. Ka ho'ololi 'ana i ke kumu kū'ai waiwai

ʻO ke kaʻina hana Andrussow a me ke ʻano methanol e hilinaʻi nei i ke kinoea maoli (methane) a me ka lanahu (ma ke ʻano he mea maka no ka methanol). Hoʻopili pololei ka fluctuations i nā kumukūʻai ikehu honua i nā kumukūʻai hana. He kumuhana noiʻi wela ka hoʻomohala ʻana i nā ala makaʻala ʻole (e like me ka biomass a me ka methanol).

2. Ke piʻi nei i ke kaumaha o ke kaiapuni

Me ka hoʻopaʻa paʻa ʻana o nā lula hoʻomalu kaiapuni honua, pono ka hana ʻana o ka sodium cyanide e hōʻemi hou i ka hoʻokuʻu ʻana o nā nitrogen oxides (NOx) a me ka wai ʻōpala cyanide. Ua hoʻokele ʻia ka ʻenehana hoʻokaʻawale membrane, catalytic oxidation denitrification, a me nā kaʻina hana ʻē aʻe i kekahi mau hale hana.

3. Hoʻonui i nā noi kiʻekiʻe

ʻO ke koi no ka sodium cyanide maʻemaʻe kiʻekiʻe (ka maʻemaʻe ≥ 99.9%) i ka synthesis o nā cathode material precursors no nā pā lithium-ion ke ulu wikiwiki nei, e hāpai ana i ka hoʻomaikaʻi ʻana i ke kaʻina hana i ka hoʻomaʻemaʻe a me ka maʻemaʻe kiʻekiʻe.

Panina

ʻO ka hoʻomohala ʻana i nā kaʻina hana hana sodium cyanide ua ulu mau a puni nā pahuhopu nui ʻekolu o ka "palekana, kūpono, a me ka ʻōmaʻomaʻo". I ka wā e hiki mai ana, me ka holomua o ka ikehu hou a me nā ʻenehana palekana kaiapuni, a me ka hoʻohui hohonu ʻana o ka hana kikohoʻe, e hoʻomau ka ʻoihana sodium cyanide i ke kuhikuhi o ka hoʻohana ʻana i ka ikehu haʻahaʻa, liʻiliʻi ka pollution, a me ka waiwai hoʻohui kiʻekiʻe.