CSIR-Central Leather Research Institute
Dr.K.J Sreeram
Sr. Principal Scientist
Academic Qualifications
Contact Details
Dr.K.J Sreeram
Sr. Principal Scientist
CLRI-Centre for Analysis, Testing, Evaluation& Reporting Services(CLRI-CATERS)
CSIR-Central Leather Research Institute
Adyar, Chennai – 600 020
e-mail: kjsreeram@clri.res.in,

About us

Current area of interest is the application of material science and nanotechnology to bring about sustainable value addition to leather. The group’s focus for research is towards finding answers to the following questions:

  • How effectively can we utilize widely available natural resources such as plant polyphenols found in nature as well as in wastes (such as lignin from black liquor of paper industry) for synthesis of engineered nanomaterials?
  • Can engineered nanomaterials have improved diffusion of chemicals into the skin matrix and thus be able to bind better at a shorter duration of time than conventional chemicals?
  • Can these engineered nanomaterials be multifunctional, so as to impart customer desired features on leather and leather products?
  • Can we understand the surface of leather better, so as to develop one-pot products that can provide customer desired features in a single go?
Academic/Professional Details
Degrees Earned
  Bachelor of Technology (Leather) – 1994
  Master of Technology (Leather) – 1996
  Doctorate (Leather) – 2000 – All from AC College of Technology, Anna University
Training Obtained
  Postdoctoral training at University of Oklahoma in nanobiotechnology (engineered phage as drug carriers) 2008 -2009
Recent News
  Delivered an invited talk at International Conference on S&T and applications of Rare Earths, 23-25 April 2015, Trivandrum
Current Positions
Principal Scientist @ Chemical Laboratory
Scientist in Charge – Centralized Sophisticated Instruments Laboratory
Nodal officer – S&T Revolution in Leather with a Green Touch (STRAIT) – XII Plan Suprainstitutional Project
Laboratory Nodal Officer – Strategic Utilization of Rare Earths (SURE) – XII Plan Project led by NIIST, Trivandrum
Honorary Assistant Professor – Department of Leather Technology, Anna University
Associate Professor – Academy of Scientific and Innovative Research (AcSIR)
Editorial Board Member – TIFAC Vision 2035 for Manufacturing Sector
Research Interests
Patents filed and granted
Sl.No Patent.No. Appln. No Date of Filing Patent Details



A novel silica based organic colorant for leather and a process for the preparation thereof; S Ramalingam, KJ Sreeram, JR Rao, BU Nair




An improved tanning process; M Sathish, KJ Sreeram, B Madhan, JR Rao, BU Nair



1786/DEL/2014   A waterless tanning process for making leather; S Silambarasan, GC Jayakumar, P Thanikaivelan, KJ Sreeram, JR Rao, BU Nair



A novel melamine-chrome complex for leather processing and a process for the preparation thereof; KJ Sreeram, S Sangeetha, GC Jayakumar, JR Rao, BU Nair

5.   86/DEL/2014  

An inorganic blue colorant and a process for the preparation thereof; KJ Sreeram, S Radhika, BU Nair




An improved post tanning process for leather; GC Jayakumar, KJ Sreeram, R Usha, A Dhathathreyan, JR Rao, BU Nair



3193/DEL/2012 12/10/2012 A condensate of amino resin with polysaccharide and/or polyphenol and a process for the prepaparation thereof; KJ Sreeram; S Sangeetha; JR Rao, BU Nair


0648/DEL/2007 23/03/2007 A process for the preparation of novel synthetic tanning agent; P Nataraj, S Subramani, R Aravindhan, KJ Sreeram, JR Rao, BU Nair, T Ramasami


1276/DEL/2005 31/03/2005

A process for making wet-pink leather; M Chandrabose, NN Fathima, KJ Sreeram, JR Rao, BU Nair and T Ramasami

(US Patent No. 7252687 dated 7/8/2007)


3333/DEL/2005 09/12/2005

Nanosized sulphide compounds of cerium and a process for the preparation thereof; KJ Sreeram, HY Srivastava, BU Nair, T Ramasami, UV Varadaraju

(US Patent No. 7247291 dated 24/07/2007)


1262/DEL/2005 31/03/2005

A process for the preparation of inorganic colorants from mixed rare earth compounds; KJ Sreeram, BU Nair, T Ramasami

(US Patent No. 7279036 dated 9/10/2007)


1093/DEL/2002 30/10/2002

A process for simultaneous recovery of chromium and iron from chromite ore processing residue; KJ Sreeram, T Ramasami

(US Patent No. 7220394 dated 22/05/2007)


906/DEL/2000 06/10/2000

A process for the preparation of a novel synthetic tanning agent; M Kanthimathi, P Thanikaivelan, KJ Sreeram, JR Rao, R Sundaram, BU Nair, T Ramasami



446/DEL/1999 19/03/1999

A process for the preparation of a novel chromium-iron complex for use in leather industry; JR Rao, KJ Sreeram, P Thanikaivelan, BU Nair, T Ramasami



3077/DEL/1998 20/10/1998

A process for the preparation of novel organometallic polymeric matrix useful as tanning agent; KJ Sreeram, M Kanthimathi, JR Rao, R Sundaram, BU Nair, T Ramasami

Books/Chapters Authored


Chapter 4 Industrially relevant nanoparticles – hematite. In Advanced Nanomaterials: Synthesis, Properties and Applications, CRC Press



Encyclopedia of Metalloproteins – Chromium and Leather; Springer.
ISBN: 978-1-4614-1532-9



Advances in Industrial Wastewater Treatment (Goel PK ed) - Some Strategies Towards Mitigation of Pollution From Tanneries: A Review; Technoscience Publications, Jaipur, India: ISBN: 978-8-1857-7161-8



Vision for Leather Industry 2035 – Chapter for Manufacturing Sector, TIFAC, DST  New Delhi

Sponsored/Consultancy Projects
1. M/s. Tata Steel, Jamshedpur
2. M/s. Sri Rakka Chemicals, Chennai
3. M/s. Balmer Lawrie & Co. Ltd., Kolkata
4. M/s. Hindustan Lever Limited, Panruti
5. M/s. KKSK Leathers, Erode
6. M/s. Kanakadurga Chromates, Nellore
Salient Features of Sponsored/Consultancy Projects
a. Can there be a replacement for Fe(II) sulfate for reducing Cr(VI) in chromite fines?

Issue addressed: Chromite fines and during this process generates Cr(VI) in the ore, limits for which was 0.03 ppm. They were employing an Fe(II) sulfate washing, which led to large quantities of sulfate in the chromite ore leading to unacceptable color. After a careful analysis of the redox potentials, Dr Sreeram’s group identified a natural source – Myrobalan, spraying of which resulted in complete reduction of Cr(VI), within a contact time of 5 sec. Added advantage of the process was that it also prevented any further formation of Cr(VI)

b. Making high exhaust basic chromium(III) sulfate

The group at Chemical laboratory, CLRI has a good understanding of how uptake of chromium in tanning process can be tuned through preparation of the tanning salt. Dr Sreeram’s contribution to this project was the optimization of Cr(VI) to reducing agent ratio and the role of temperature to ensure that dimeric Cr(III) was formed as against the cyclic tetramer.

c. Can we enhance chromium uptake through tanning aid?

One of the requirements of the leather processing activity is to ensure that penetration of chromium preceeds its fixation. Towards this several exhaust aids are employed. However, they either have formaldehyde as a crosslinker or result in improper binding of chromium. Dr Sreeram and colleagues developed a polymeric synthetic tanning agent that when offered prior to chrome tanning ensure complete uptake of chromium and also provided for fuller leather. The aid also enabled avoidance of pickling, a process prior to tanning which resulted in high salinity in wastewater. TANAID is a very successful product.

d. Moving from batch to continuous chrome recovery?

Nucleation and particulation chemistry tells us that slower the nucleation process larger the aggregate and for this reason the precipitation of chromium(III) to chromium(III) hydroxide as a part of recovery/reuse of chromium in tannery wastewaters employed MgO. However, MgO turns to MgSO4 causing hardness to water. When large quantities of oil is present, the formation of magnesium soaps hampers the precipitation, a case observed at M/s. Hindustan Lever Ltd., where they were processing sheep skin. Through appropriate study of the zeta potentials associated with the precipitation process, Dr Sreeram was able to design a reactor which not only provided for lesser sludge volume when using sodium carbonate but also turned the reaction from one of batch type (limitation from poor solubility of MgO) to a continous reactor

e. What limits direct recycling of chromium?
  When a tanner tries to recycle the spent chrome tanning wastewater directly into the next batch, it results in surface fixation thus leading to the need for recovery as hydroxide and reuse. Through understanding of chromium chemistry, it was found that the spent liquor containing significant proportion of large sized tetracyclic tetrameric species was the cause for surface fixation. A process by which the pH of the spent liquor was reduced to less than 1 resulted in a liquor carrying dimeric species. A package complete with engineering design for reaction vessel for pH adjustment, feeding into drum etc. was provided to a tanner in Erode district of TN.
f. How do you tune a self-basifying chromium?

In leather processing, after the penetration of chromium is achieved, the chrome tanning salts are bridged through a process called basification. This is an additional step. Taking cue from the precipitation chemistry studied earlier a self basifying chromium carrying Cr(III) and MgO was developed and provided.

Ten Most Significant Refereed Journal Papers


Title of paper Journal Vol/Year Pg. Nos Citations
1. Nidhin, M.; Indumathy, R.; Sreeram, K. J.; Nair, B. U Synthesis of iron oxide nanoparticles of narrow size distribution on polysaccharide templates Bulletin of Materials Science 31, 2008 93-96 62
2. Sreeram, K. J.; Srinivasan, R.; Devi, J. M.; Nair, B. U.; Ramasami, T. Cerium molybdenum oxides for environmentally benign pigments Dyes and Pigments 75, 2007 687-692 38
3. Sreeram, K. J.; Shrivastava, H. Y.; Nair, B. U Studies on the nature of interaction of iron(III) with alginates Biochimica et Biophysica Acta-Gen. Subjects 1670, 2004 121-125 38
4. Sreeram, K. J.; Nidhin, M.; Nair, B. U. Microwave assisted template synthesis of silver nanoparticles Bulletin of Materials Science 31, 2008 937-942 35
5. Sreeram, K. J.; Aby, C. P.; Nair, B. U.; Ramasami, T. Colored cool colorants based on rare earth metal ions Solar Energy Materials and Solar Cells 92, 2008 1462-1467 30
6. Sindhu, K.; Indra, R.; Rajaram, A. Sreeram, K. J.; Rajaram, R. Investigations on the Interaction of Gold-Curcumin Nanoparticles with Human Peripheral Blood Lymphocytes Journal of Biomedical Nanotechnology 7, 2011 56-56 29
7. Sreeram, K. J.; Indumathy, R.; Rajaram, A.; Nair, B. U.; Ramasami, T. Template synthesis of highly crystalline and monodisperse iron oxide pigments of nanosize Materials Research Bulletin 41, 2006 1875-1881 26
8. Nidhin, M; Nazeer, SS; Jayasree, RS; Kiran, MS; Nair, BU; Sreeram, KJ Flower shaped assembly of cobalt ferrite nanoparticles: application as T-2 contrast agent in MRI RSC Advances 3, 2013 6906-6912 9
9. Sangeetha, S; Usha, R; Sreeram, KJ; Nair, BU Enhancing collagen stability through nanostructures containing chromium(III) oxide Colloids and surfaces. B, Biointerfaces 100, 2012 36-41 6
10. Sangeetha, S.; Basha, R.; Sreeram, K.J.; Sangalimuthu, S. N.; Nair, B. U. Functional pigments from chromium(III) oxide nanoparticles Dyes and Pigments 94, 2012 548-552 6
Research in Coverpages
Research in a Nutshell

Sustainable chemistry is the central theme of research of Dr KJ Sreeram. His research during the last ten years have been predominantly dominated towards using nanoscience to develop solutions to existing problems in coloring and tanning industries.

  Nanoscience inputs for colorants and added advantages thereon
  Synthesis of iron oxide nanoparticles in the nano range has been very exciting and challenging area of research. Sensitivity of the preparative strategy complicates both reproducibility and scale up of the process. Dr Sreeram has done brilliant work in advancing the field of hematite nanoparticles, especially in the design and template based synthesis of highly monodisperse α-Fe2O3 nanoparticles, a class of superparamagnetic particles with a wide range of applications. To tune the size and shape of the nanoparticles, he designed self-assembled films of chitosan-alginate, chitosan-pectin and starch on to which Fe2+ centres could interact in a spatially separated manner. This was followed by a careful calcination of the film to provide for nanoparticles below 30 nm and having a polydispersity

index of less than 0.15. Dr Sreeram was the first investigator to demonstrate the synthesis of hematite nanoparticle using sacrificial polysaccharide templates – in more than three ways, viz., calcination of dried polysaccharide – iron complex, calcination of polysaccharide films carrying Fe2+ centres and low temperature reflux synthesis from Fe-starch complexes (2 papers in these area have put together received 100 citations). He has demonstrated that these procedures can be extended to synthesis of CoO and cobalt ferrite nanoparticles as well. He has shown that these iron oxide nanoparticles can be used crosslink collagen leading to several biomedical applications. Cobalt ferrite nanoparticles synthesized by this method also had an unusual MRI contrast (9 citations within one year of publication). He built on this early work in the construction of functionally useful nanomaterials that were optimized for high luminescence through a natural product – catechin based tuning of size, shape and polymorph character. One of the significance of Dr Sreeram’s work has been that all the synthesized nanoparticles are tested for their toxicity to various cells. For instance, his work on how gold nanoparticles, synthesized through a green route using curcumin as a reducing agent, would interact with human peripheral blood lymphocytes has been much discussed by the research community.
  Finding replacement to toxic transition metal ion based pigments in rare earths
  Dr Sreeram today is a leader in the exciting new area of material chemistry, viz. the development of rare earth based pigments. He has done landmark work that has advanced the applications of rare earth oxides as pigments for coloring plastics, ceramic and leather. Through careful tuning of the bandgap energies by appropriate doping into the lanthanide lattice (light RE), colors in the range of blue, yellow and brown-red have been obtained. The mass tone, hiding power, tint strength and applications as colorant for leather, plastics and exteriors have been optimized through a new route of synthesis, viz., sol-gel-microwave irradiation as against the conventional solid state synthesis. His publications in this area have been well received (over 200 citations). Understanding that such products can only be cost effective when raw material costs are brought down, Dr Sreeram developed a process for the preparation of these pigments from mixed rare earth chlorides – a byproduct of the thorium extraction process. M/s. Indian Rare Earths Limited investigated the upscalability of this process at their Kollam unit. M/s. IREL suggested that the process was viable and marketable.
  Exploiting size and shape tuning for deeper applications such as turning leather into sensors and developing cool pigments
  The thrust of Dr Sreeram’s research has been the deepening of the applications of existing knowledge through modifications in synthesis strategies, size tuning etc. His work on turning phenomena of chromism into an attractive option for obtaining smart leathers, such as the use of doped chromium(III) isocyanate as surface coating on leather to get solvato or thermo-chromism based effects, coating leather with RE complexes to obtain UV sensing ability and use of PdO-ZnO nanocomposites as surface coatings to turn leather from brown to black on exposure to hydrogen, such as when hydrogen leaks from a gas driven vehicle has attracted the attention of leather community.

He proposed that the addition of a rare earth metal ion and/or reducing the crystal size of resultant pigment to less than 10 nm could result in near infra red reflectivity from the coated surface. Range of pigments whose, solar irradiance R* values were 10-30 units more than commercial pigments were developed and tested by his group. The advantage of such pigments is to provide for thermally comfortable surfaces, where prior to this work, the color is limited to white and pastel shades. Through thermal imaging his group demonstrated that the surface temperature of leather and concrete surfaces coated with the newly developed pigments were at least 3 – 5 deg. C lesser than conventional, even without a white base coat. That a light absorbing color like black could be turned into a light reflecting pigment was demonstrated through synthesis of CoO nanoparticles on polysaccharide templates, an aspect that the Chemical Engineering J covered on its Cover page.
  Developing sustainable chemistry for leather sector – complete with upscaling and demonstration
  Dr Sreeram continues his passion for green chemistry based alternatives for chromium. Starting from his contributions to greening of chromium based industries such as methods for handling chromium ore processing residues to developing high exhaust chrome tanning methods, contributions that led to his receiving the CSIR Young Scientist Award in 2004, Dr Sreeram has gone on to develop a range of formaldehyde free synthetic tanning agents for the leather sector, a few of which have been commercialized. One of the recent innovations in this area has been the development of a chromium – melamine complex synthetic tanning agent devoid of formaldehyde as a crosslinker, specifically suited for raw material from Indian origin. He has also developed methods for converting chromium bearing solid wastes from leather sector as well as black liquor from paper and pulp industry for preparation of leather auxiliaries (over 70 citations). This aspect of his has been considered as a positive development by the leather sector, who in their vision for 2030 have suggested that leather chemicals should be developed from within the industry itself.
Significant Awards
CSIR Young Scientist Award – Engineering Sciences 2004
Member Royal Society of Chemistry – 2012


Mrs. V. Tamilmani
Senior Research Fellow- Inspire(DST) (Registered: 2011)
Area of research: Luminescent Rare Earth Nanoparticles 

Senior Research Fellow - DBT (Registered: 2013)
Area of research: Functionalized Nanostructures for Collagen Stabilization

Ms. N. Bhargavi
Junior Research Fellow, SURE Project (Registered:2015)
Area of research: Viscogens and Fusogens in Lipid structure Modulations 

Project Assistant (Registered:2015)
Area of research: Polyphenol Functionalized Nanoparticles for sustainable leather processing