Extraction of Vanadium(V) from Mixed Chloride/Thiocyanate Solutions with Two Commercial Solvating Extractants

Studies on the extraction and separation of vanadium(V) from mixed hydrochloric acid/ammonium thiocyanate solution with CYANEX 921 and CYANEX 925 in kerosene were carried out. The effects of various factors affecting the extraction process as well as temperature were investigated. Addition of thiocyanate to the chloride solution was found to enhance markedly the extraction of vanadium. HCl solution efficiently stripped V(V). The number of stages required for extraction and stripping of vanadium ions was determined from the McCabe–Thiele diagram. Based on the obtained results, the separation of V(V) from spent catalyst leach indicates the efficiency of the proposed process.     

灰吹留铅—硫氰酸钾滴定联合原子吸收测定铅精矿银量

本方法适合于铅精矿银含量在1000~2000g/t。此方法采用灰吹留铅1~2g左右,用硫氰酸钾滴定银量w1与灰渣配料二次试金,灰吹留铅0.5g左右,硝酸溶解定容,原子吸收测定渣中银量w2,两者之和即为最终测定值。实验中用与试样等量银粉和纯铅混合滴定,验证回收率及留铅干扰程度。     

提高化学示踪剂检测准确度实验研究

针对胜坨油田地层水组分复杂、加药类型多,影响化学示踪剂检测准确度的问题,开展了硝酸盐、硫氰酸盐、尿素3种示踪剂的检测准确度分析。结合示踪剂检测方法,对比了蒸馏水、注入污水、采出液配制示踪剂溶液的检测差异,提出了制作标准曲线的方法;开展了氮气泡沫驱起泡剂、注水用缓蚀剂、杀菌剂、二元复合驱用表面活性剂对示踪剂检测结果的影响研究。结果表明,尿素示踪剂的检测受各类药剂的影响较小,且成本较低,确定为适合胜坨油田的示踪剂。现场应用验证了示踪剂检测方法的适应性。     

An efficient and regioselective thiocyanation of aromatic and heteroaromatic compounds using cross-linked poly (4-vinylpyridine)-supported thiocyanate as a versatile reagent and potassium peroxydisulfate as a strong oxidizing agent

A green and regioselective thiocyanation of aromatic and heteroaromatic compounds has been achieved via a simple protocol using cross-linked poly (4-vinylpyridine)-supported thiocyanate ion, [P₄-VP]SCN, as a versatile polymeric reagent and potassium persulfate as a strong oxidizing agent, under heterogeneous conditions.

Various indoles, phenol and aniline derivatives, and pyrroles were transformed into their corresponding aryl thiocyanates in high to excellent yields. This procedure offers advantages such as short reaction time, simple reaction work-up, and the polymeric reagents can be regenerated and reused for several times without significant loss of their activity.     

钨矿石中硫氰酸盐比色法测定钨

钨的比色法适用于ω(WO₃)小于2%样品的测定,试样以过氧化钠熔融,水浸取,铁、锰等成氢氧化物沉淀而与钨分离。控制最佳的酸度、温度、时间,采用氯化亚锡—三氯化钛双还原剂,钨与硫氰酸盐形成稳定的黄色络合物,通过对国家一级标准物质进行分析验证,测试的准确度及精密度均达到地质样品规范要求。     

Cyclic ammonium salts of dithiocarbamic acid: stable alternative reagents for the synthesis of S-alkyl carbodithioates from organyl thiocyanates in water

Carbodithioate esters are important functional organosulfur compounds widely used in diverse fields such as pharmaceuticals, agrochemicals and material sciences. Common preparative methods include reaction of alkyl halides, carbon disulfide and bases under both metal-free and metal-catalyzed conditions. However, organyl thiocyanates have not been previously explored, possibly because of their conversion to organyl disulfides under basic conditions. Here, we report an efficient and practical method for the preparation of libraries of carbodithioate esters from organyl thiocyanates by reacting with cyclic amine-based dithiocarbamic acid salts in water. The protocol is found to be applicable in general to various thiocyanates such as benzyl/aroyl methyl/cinnamyl and so on. Other notable features include no by-products such as disulfides, metal- and alkali-free, aqueous conditions, and finally easy and near-quantitative formation of cyclic amine-based dithiocarbamic acid salt as a stable alternative reagent.     

Ultrasound-promoted one-pot four-component synthesis of novel biologically active 3-aryl-2,4-dithioxo-1,3,5-triazepane-6,7-dione and their toxicity investigation

We have described a novel four-component reaction (4MCR) between oxalyl chloride 1, anilines 2a–h, and two molecules of ammonium thiocyanate 3 in acetone under ultrasound irradiation to give 3-aryl-2,4-dithioxo-1,3,5-triazepane-6,7-diones. A synthetically useful ultrasound effect was observed and title products were obtained in high yields after 15–35?min sonication. Our procedure compared to the conventional heating method has the benefit of higher reaction yields and shorter reaction times. The IR spectra showed the presence of N–H, C═O and C═S groups in these compounds and ¹H, ¹³C NMR and Mass spectral results verified their structures. Cellular investigations showed that these compounds are toxic toward cancer cells.     

无溶剂条件下微波辅助合成硫氰酸酯类化合物

芳基硫氰酸酯是重要的有机合成中间体,得到越来越广泛的应用。文章研究了无溶剂条件下微波辅助合成的方法,用此方法合成了一系列的芳基硫氰酸酯。反应在几分钟内就能完成,并且收率大多在80%以上。该方法操作简单,反应时间短,产率高,环境友好,符合绿色化学的发展要求。