HGT3441-1976化学试剂焦硫酸钾(原HGT3-921-76).pdf 3页

'中华人民共和国石油化学工业部部标准化学试剂HG3-921-76焦硫酸钾本试剂为白色块状结晶，溶于水。分子式:K2SZ07分子量:254.3(按1975年国际原子量)一、技术条件1.K2Sz0:含量不少于:分析纯1，，，，·价·····‘·“·，····““······，，·····价，·······”·，····“⋯98.0;化学纯·································································⋯⋯97.0%.2.杂质最高含量(指标以%计):名称}分析纯}一化一孚-瓦(1)澄清度试验合格合格(2)水不溶物0.010.015(3)抓化物(CD0.0010.003(4)磷酸盐(PO,)0.0010.0015(5)钙及镁(以Ca计)0.0050.01(6)铁(Fe)0.0010.003(7)砷(As)0.00030.0005(8)重金属(以Pb计)0.00050.002二、检验规则按GB619-77之规定进行取样及验收.三、试验方法测定中所需标准溶液、杂质标准液、制剂及制品按GB601-77,GB602-77,GB603-77之规定制备1.K2S必7含量测定:称取4克样品，称准至。.0002克。溶于50毫升水中，加2滴。.1%甲基红指示液，用1N氢氧化钠标准溶液滴定至溶液呈黄色.K多刃7含量%(x)按下式计算:x=竺"cx0.127;X100t工式中:V-氢氧化钠标准溶液之用量，毫升;中华人民共和国石油化学工业部发布1977年10月1日施上海市化工局提出上海试荆二厂草 HG3-921-76(-一一氢氧化钠标准溶液之当量浓度，N;G一样品重量，克;0.1272一每毫克当量K2S207之克数。2.杂质测定:样品须称准至。.01克。(1)澄清度试验:称取10克样品，加10。毫升水，加热溶解，其浊度不得大于澄清度标准:分析纯····································································⋯⋯2号;化学纯····································································⋯⋯4号。(2)水不溶物:称取20克样品，溶于200毫升水中，在水浴上保温1小时，用恒重的4号玻璃滤祸过滤.以热水洗涤滤渣至洗液无钾离子反应，于105-1100C烘至恒重。滤渣重量不得大于:分析纯··············。··················································⋯⋯2.。毫克;化学纯····································‘···················。·········⋯⋯3.。毫克。(3)氯化物:称取1克样品，溶于25毫升水中，加2毫升5N硝酸及1毫升0.1N硝酸银，摇匀，放置10分钟。所呈浊度不得大于标准。标准是取下列数量的CI,分析纯·······························································⋯⋯。.01毫克;化学纯··························································⋯⋯。.03毫克。与样品同时同样处理。(4)磷酸盐:称取2克样品，溶于10毫升水中，加5毫升氨水.在水浴上蒸干，残渣溶于10毫升水中，加2滴饱和2.4一二硝基酚指示液，用4N硫酸中和至黄色消失，稀释至20毫升，再加4毫升4N硫酸及磷试剂甲、乙各1毫升，摇匀，于60"C水浴中保温10分钟。所呈蓝色不得深于标准。标准是取下列数量的P04分析纯··········································。····················⋯⋯。02毫克;化学纯··············································。················⋯⋯。.03毫克。稀释至20毫升，与同体积样品溶液同时同样处理。(5)钙及镁:称取5克样品，溶于25毫升水中，用1000氨水中和，加2毫升2%新制备的硫化钠溶液.1毫升乙二胺四乙酸镁溶液，加10毫升氨一氯化钱缓冲溶液甲(pHlo)，加2滴0.5%铬黑T指示液，用。.02M乙二胺四乙酸二钠标准溶液滴定至溶液呈蓝色，0.02M乙二胺四乙酸二钠标准溶液用量不得多于:分析纯····················。····。·····································⋯⋯。.30毫升;化学纯····················。·········································⋯⋯。.60毫升。(6)铁:称取1克样品，溶于10毫升水中，用10Yo氨水中和，冷却，稀释至20毫升，加2毫升1000磺基水杨酸溶液，摇匀，加5毫升1000氨水，摇匀。所呈黄色不得深于标准。标准是取下列数量的Fe:分析纯·························⋯⋯‘······“·················⋯⋯0.01毫克;化学纯············································，·················⋯⋯。03毫克。稀释至20毫升，与同体积样品溶液同时同样处理。(7)砷:称取1克样品，按GB610-77之规定测定。澳化汞试纸所呈棕黄色不得深于标准标准是取下列数量的As;分析纯··········································。····················⋯⋯。.003毫克;化学纯··························································。··⋯⋯。.005毫克。与样品同时同样处理(S)重金属:称取4克样品，溶于25毫升水中，用1000氨水中和，稀释至40毫升，取30毫升，稀释 HG3-921-76至40毫升，加1毫升1N乙酸及10毫升新制备的饱和硫化氢水，摇匀，放置10分钟。所呈暗色不得深丁标准标准是取剩余的10毫升样品溶液及下列数量的Pb;分析纯····，····················。·····‘·······························⋯⋯。01毫克;化学纯···............................................................·一。04毫克。稀释至40毫升，与同体积样品溶液同时同样处理。四、包装及标志1.包装:按HG3-119---64之规定。内包装形式:G-2,Gz-2,G-3,Gz---3;外包装形式:工一1;包装单位:第4类2.标志:按HG3-119-64之规定。'