Council of Scientific & Industrial Research

Maheshkumar Ramniklal Gandhi

Pushpito Kumar Ghosh

Himanshu Labhshanker Joshi

Vadakke Puthoor Mohandas

Hasina Hajibhai Deraiya

Jatin Rameshchandra Chunawala

Pratyush Maiti

Sohan Lal Daga

Rajinder Nath Vohra

Kaushik Jethalal Langalia

Koushik Halder

Rohit Harshadray Dave

Rohit Harshadrai Dave

Hari Chand Bajaj

Rahul Jasvantrai Sanghavi

Haresh Mahipatlal Mody

Satish Hariray Mehta

Abdulhamid Usmanbhai Hamidani

Kishorkumar Manmohandas Majeethia

Ramjibhai Devjibhai Rathod

Rajesh Shantilal Somani

Sumesh Chandra Upadhyay

Dibyendu Mondal

Gadde Ramachandraiah

Upendra Padmakant Saraiya

Subbarayappa Adimurthy

Mrunalben Vinodray Sheth

Mallampati Subbareddy

Rajendra Patil

Girdhar Joshi

Ashokkumar Bhagvanjibhai Kasundra

Purashottambhai Ravajibhai Jadav

Hasina Hajibhai Deriya

Sohanlal Daga

Abdulhamid Usmanbhai Hamdani

Himanshu Labshanker Joshi

Harshad Brahmbhatt

Manoj Kunjabihari Agrawal

Paresh Ukabhai Patoliya

The present invention relates to stable and white iron fortification and iron+iodine double fortification agents, their preparation and use in fortification of salt. These agents help overcome the normal difficulties encountered in iron and iodine fortification such as low iodine stability on storage, development of colour and odour, and use of unwanted additives to impart stability. In one of the invented products, both iron and iodine coexist in stable manner in the same matrix which allow for a more uniform distribution of iodine. The process of preparation is demonstrated to be scalable and utilizes commonly available raw materials which would enable the products to be synthesized in affordable manner.

Double fortified salt composition containing iron and iodine and process for the preparation thereof

Development of a novel process for preparation of synthetic hydrotalcite using three industrial wastes such as aluminum chloride waste-generated in any of reaction where anhydrous aluminum chloride is used as Leawis acid catalyst such as Freidel Craft reaction, bittern containing magnesium compounds generated in solar salt work using brines such as sea brine and subsoil brines containing magnesium, and ammonium carbonate solution generated in organic pigment industries such as producing copper pthalo cyanin green. The process involves preparation of aluminum precursor and removing metallic impurities present in Aluminum hydroxide prepared from aluminum chloride containing waste, preparation of magnesium precursor, mixing the precursors, hydrothermally treating the mixture and adding surface modifying agents followed by filtration and drying.

Process for preparation of synthetic hydrotalcite from industrial waste

The present invention provides an integrated process for the recovery of sulphate of potash (SOP) and ammonium sulphate fertilizers from kainite mixed salt dispensing with magnesium hydroxide production. The process comprises, among other steps, producing calcium chloride from calcium carbonate through addition of hydrochloric acid; the calcium chloride being used for desulphatation of schoenite end liquor (SEL) obtained as liquid stream during decomposition of kainite mixed salt with water to obtain solid schoenite; using the resultant gypsum and carbon dioxide together with ammonia for the production of ammonium sulphate liquor and solid calcium carbonate, the latter being recycled in the process; producing carnallite from desulphated SEL; decomposing the carnallite to recover carnallite decomposed product (CDP) which is further refined under ambient conditions to obtain pure potassium chloride (KCl) utilized in the preparation of SOP from the schoenite. Except for ammonium sulphate recovery in solid state, where required, all operations are carried out at ambient temperature.

Integrated process of production of potassium sulphate and ammonium sulfate from kainite mixed salt

A method of producing soda ash and ammonium sulphate by recycling by-products of Merseberg and Solvay processes includes treating brine with soda ash distiller waste for desulphatation of the brine to obtain gypsum, recovering pure salt from the desulphated brine and utilizing it in manufacture of soda ash in a Solvay process, washing the gypsum and reacting it with liquor ammonia and carbon dioxide to obtain CaCOand ammonium sulphate, separating the CaCOfrom the ammonium sulphate solution and recovering solid ammonium sulphate, washing the CaCOfollowed by calcination to generate COand lime, recycling the COin the Solvay process to obtain soda ash, recycling the lime with ammonium chloride generated in the Solvay process to recover ammonia and obtain distiller waste containing CaClas a by-product, recycling the by-product distiller waste for the desulphatation of the brine, and recycling the ammonia recovered.

Method of recycling of by-products for the production of soda ash and ammonium sulphate

A highly pure 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil) has been prepared in high yield from 4-hydroxybenzonitrile using eco-friendly brominating reagent comprising of 2:1 mole ratio of bromide to bromate salts in aqueous acidic medium without any catalyst under ambient conditions with no work up procedure. The product 3,5-dibromo-4-hydroxybenzonitrile was obtained in 91-99% yield with melting point 189-191&#xb0; C. and more than 99% purity by gas chromatographic analysis without any purification.

Process for the eco-friendly preparation of 3, 5-dibromo-4-hydroxybenzonitrile

Kainite mixed salt is treated with water to obtain solid schoenite and a schoenite end liquor. The latter is desulphated using recycled CaCland thereafter evaporated to obtain camallite crystals, from which KCl is recovered, and a liquor rich in MgCl. Gypsum produced during desulphatation is reacted with aqueous ammonia and COto produce ammonium sulphate and calcium carbonate. The calcium carbonate is calcined to obtained CaO and CO. The CaO is slaked and reacted with the MgCl-rich liquor generated above to produce slurry of Mg(OH)in aqueous CaCl. To this surface modifying agent is added while hot and, after cooling, the slurry yields surface modified Mg(OH). The filtrate rich in CaClis recycled for desulphatation process above. The solid surface modified Mg(OH)may he calcined to produced MgO. The schoenite and KCl are reacted to produce solid sulphate of potash.

Process for simultaneous production of potassium sulphate, ammonium sulfate, magnesium hydroxide and/or magnesium oxide from kainite mixed salt and ammonia

The present invention provides an improved process for the preparation of MgO of high purity &#x3e;99% from salt bitterns via intermediate formation of Mg(OH)obtained from the reaction of MgCland lime, albeit indirectly, i.e., MgClis first reacted with NHin aqueous medium and the slurry is then filtered with ease. The resultant NHCl-containing filtrate is then treated with any lime, to regenerate NHwhile the lime itself gets transformed into CaClthat is used for desulphatation of bittern so as to recover carnallite and thereafter MgClof desired quality required in the present invention. The crude Mg(OH)is dried and calcined directly to produce pure MgO, taking advantage of the fact that adhering impurities in the Mg(OH)either volatilize away or get transformed into the desired product, i.e., MgO.

Process for the preparation of magnesia (MGO)

The process provides for the preparation of MgO from the reaction of magnesium salt and alkali/lime. The crude Mg(OH)is directly calcined and then treated with water to disintegrate the mass spontaneously to yield a slurry and dissolve away the soluble salts. This slurry is much easier to filter and wash than the original Mg(OH)slurry, which helps to speed up the purification operation and also conserve fresh water. Another important advantage of the present method is that even pasty or dough like reaction products that are processed using dough mixers and similar equipment can be worked up with ease. There is no compromise in the quality of MgO achieved in this manner.

[object Object]

The present invention is directed to a novel integrated process for the recovery of sulphate of potash (SOP) from sulphate rich bittern. The process requires bittern and lime as raw materials. Kainite type mixed salt is obtained by fractional crystallization of the bittern, and is converted to schoenite which is subsequently reacted with muriate of potash (MOP) for its conversion to SOP. End liquor from kainite to schoenite conversion (SEL) is desulphated and supplemented with MgClusing end bittern generated in the process of making carnallite. Decomposed carnallite liquor produced is reacted with hydrated lime for preparing CaClsolution and high purity Mg(OH)2 having low boron content. It is shown that the liquid streams containing potash are recycled in the process, and the recovery of potash in the form of SOP is quantitative.

Process for recovery of sulphate of potash

The present invention relates to recovery of industrial grade potassium chloride and low sodium edible salt from bittern as part of an integrated process. The process comprises, mixing low sulphate concentrated feed bittern (a by-product of salt industry) of density 31.5 to 32.5&#xb0; Be (sp.gr. 1.277&#x2013;1.289) with high density end bittern of density 36.5 to 37.5&#xb0; Be' (sp.gr. 1.336&#x2013;1.35), thereby producing low sodium carnallite, from which industrial grade potassium chloride is produced. The resultant bittern is evaporated in forced evaporation system, thereby producing crude carnallite, from which low sodium salt that would be beneficial to persons suffering from hypertension is produced. When sulphate-rich bittern is used, such bittern is desulphated with CaClthat is generated from carnallite decomposed liquor through reaction with lime, and wherein low BO-containing Mg(OH)is a by-product. The entire content of potassium in feed bittern is recovered in the process of the invention.

Simultaneous recovery of potassium chloride and KCL enriched edible salt

A new process for recovery of Low Sodium Salt from bittern has been described in the present invention, the said process comprising desulphatation of bittern (by-product of salt industry), evaporation of bittern in solar pans and processing of solid mixture with water to produce a mixture of sodium and potassium chlorides and optionally preparing 'free flowing' and iodized, by known techniques.

Process for recovery of low sodium salt from bittern

The present invention relates to a non-hazardous brominating reagent from an aqueous alkaline bromine byproduct solution obtained from bromine recovery plant and containing 25 to 35% bromine dissolved in aqueous lime or sodium hydroxide containing alkali bromide and alkali bromate mixture having bromide to bromate stoichiometric ratio in the range of 5:1 to 5.1:1 or 2:1 to 2.1:1 and a pH ranging between 8-12 and also relates to a method for borminating aromatic compounds by using the above brominating agent.

Preparation of non-hazardous brominating reagents

Growing community of inventors

Bhavnagar, India

Maheshkumar Ramniklal Gandhi