- Invited talk at Indo-Japan Joint Workshop on Frontiers in Analytical & Applied Pyrolysis for Energy & Environment (FAAPEE-2024) during 26-27 February 2024 at IIT Madras
- Invited talk at 3rd International Symposium on Carbon & Functional Materials for Energy & Environment during 21-24 February 2024 at Vietnam
- Invited talk at International Chemical Engineering Conference on Energy, Environment and Sustainability during 15-17 February 2024 at IIT Roorkee
- Invited talk at Valorization 2024-International Conference on Science & Technology Integration for Circular Economy during 18-19 January 2024 at organised by DST-PURSE Team at BITS Pilani Hyderabad Campus
- Keynote Lecture at 3rd National-level workshop, “Bioprocessing Strategies for Biofuels: Production, Modelling, Simulation and Optimization” during 26-30 December 2023 at the Centre for Bioenergy, School of Chemical and Biotechnology, SASTRA University, Thanjavur
- Delivered lecture for Refresher Course in Bio Science (virtual mode) organized by the UGC-Human Resource Development Centre, BHU for College and University teachers held during December 06 - 19, 2023.
- Invited talk at National Workshop on “Biochar and Bio-resources” during 14 and 15 December 2023 at CSIR-IMMT, Bhubaneswar
- Invited talk at International Conference on Emerging Trends and Innovations in Biotechnology 2023 during 30 November to 3 December 2023 at MACFAST, Tiruvalla
- Invited talk at NHBT-2023 during 26-29 November 2023 at CSIR-NIIST, Trivandrum
- Invited talk at 2nd International Conference on Advances and Innovations in Biotechnology for Sustainable Bioresources and Bioeconomy (AI-BSBB 2023) during 22-25 November 2023 at AKS College, Satna
- Invited talk at the 6th International Conference on Alternative Fuels, Energy & Environment: Future and Challenges (ICAFEE 2023) during 6-8 October 2023 at Kayseri, Türkiye
- Invited talk at 3rd International Conference on Sustainable Solid Waste Treatment and Management (SWTM-2023) during July 28-31, 2023 in Yangling, China
- Plenary talk at the 4th International Conference for Bioresource Technology for Bioenergy, Bioproducts & Environmental Sustainability during 14-17 May 2023 at Lake Garda, Italy
- Invited talk at Waste biorefinery towards a sustainable circular bioeconomy, Life EBP Training school 2023 on 27th April 2023
- Invited talk at International Conference on Sustainable Waste Management and Resource Recovery (SWMR-2023) during 14-16 April 2023 at Northwest A&F University, China
- Invited talk at Indo-French Workshop on Clean and Sustainable Energy Technologies (INFINITE) during 21-24 February 2023 at CSIR - NPL, New Delhi
- Invited talk at International Conference on Innovations to Transform Drylands, 21-23 February 2023, at ICRISAT, Hyderabad, Telangana
- Invited talk at IEA BIOENERGY Task 34 – Direct Thermochemical Liquefaction Workshop, HP Green R&D Centre (HPGRDC), Bengaluru during 30th and 31st January 2023
- Invited talk at High-end workshop on biomass and waste-based-CCHP applications during 19-23 December 2022 at NIT, Rourkela
- Invited lecture at VII International Conference on Sustainable Energy & Environmental Challenges during 16-18 December 2022 at IIT BHU, Varanasi
- Invited lecture at International Conference on Biotechnology, Sustainable Bioresources and Bioeconomy (BSBB 2022) during 7-11 December 2022 at IIT, Guwahati
- Plenary Speaker at “BCSIR Congress-2022” during 01-03 December 2022 at BCSIR, Dhaka.
- Invited talk at National Conference on Environmental and Industrial Biotechnology (NCEIB-2022) during November 10-12, 2022, Kanpur, UP at Atal Bihari Vajpayee Research Centre, Dr. Ambedkar Institute of Technology for Handicapped
- Invited lecture at 1st International Conference on Sustainable Waste Management and Resource Recovery (SWMR-2022) during November 2-4, 2022 at Hunan Agricultural University, Changsha, China
- Invited talk at X Biennial International Forum on Industrial Bioprocessing – the International Conference of the International Bioprocessing Association during October 27-30, 2022 at National Kaohsiung University of Science and Technology, Taiwan
- Invited talk at meeting on Approaches for E-waste Management organised by DBT-BIRAC on 14th October 2022 at New Delhi
- Keynote talk at International Symposium on Sustainable Urban Environment (ISSUE-2022) oranised by UPES, Dehradun during 11-14 October 2022
- Invited talk at One-day conference on “Publication Ethics and Effective Scientific Writing for Enhancing Publication Success” organised by Association of Food Scientists and Technologists (India) at SRM University on 9th September 2022
- Invited talk at Taiwan-India 2022 Exchange Workshop and Symposium on Intensifying the Connection of Sustainable Technology during 4-6 September 2022 organised by IIT, Guwahati
- Invited speaker at the International Conference of Sustainability: Integrated and Scientific Approach (ICS-2022) during 4-6 August 2022 organised by University of Mumbai
- Invited talk at Two day International seminar on Current Trends and Futuristic Challenges in Chemical Sciences organised by Department of Chemistry, Osmania University on 29 and 30 July 2022
- Invited talk (Chief Guest of the valedictory function) at Swachhata Pakhwada by Rajiv Gandhi Institute of Petroleum Technology (RGIPT) on 15 July 2022
- Invited talk at Environment and Sustainability Department, CSIR-IMMT, Bhubaneswar on 7th July 2022
- Plenary talk at Biospectrum 2022- An International Conference on “Biotechnological Advances towards Sustainable Development” during 27-29 June 2022 organised by The School of Biosciences, Mar Athanasios College for Advanced Studies Tiruvalla (MACFAST), Kerala
- Keynote lecture at 3rd International Conference on Bioprocess for Sustainable Environment and Energy (ICBSEE-India-2022) during 20-24 June 2022 organised by NIT, Rourkela
- Invited lecture at DST PURSE II sponsored IQAC enabled 4th International Conference (Online) on Challenges in Chemical and Biochemical Engineering for Sustainable Development during 23-24 March 2022 organised by Department of Chemical Engineering, Annamalai University
- Invited talk at Faculty Development Program titled Role of Basic Sciences in Emerging Technologies (RBSET-2022) organised by GMR Institute of Technology and NIT Mizoram from 10-14 March 2022
- Invited lecture at IGCS Winter School on "Sustainable Waste Management for a Circular Economy", 21 Feb 2022 to 4 Mar 2022 organised by IGCS and IIT, Madras
- Invited lecture on Strategic design for effective utilisation of Waste Polymeric Materials on the occasion of National Science Day on 28 February 2022 at DRDO DEAL
- Invited lecture in Workshop on “Challenges & Opportunities towards Sustainable Energy & Environmental Technology in India" during February 21-25, 2022 at NIT Uttarakhand
- Faculty Development Programme (Online) on Biovalorisation: Trend and Prospects of Value Added Products, 3-7 January 2022 by NIT, Andhra Pradesh
- Invited lecture at the STTP on “Research for Sustainable Progress”, 16-22 December 2021 by LD College of Engineering, Ahmedabad
- Member, panel discussion on the topic “Idea of Circular Economy” at the Eco-Fest, IISF 2021 on 13th December 2021
- International Symposium on Feedstock Recycling of Polymeric Materials (e-ISFR), 29-30 November 2021
- Invited lecture at Interaction meet with stakeholders on standardisation of solid biofuels briquettes/ pellets, 11-12 November 2021 at CSIR-CIMFR
- A One Day International Webinar on Recycling - Solid waste management by Department of Chemical Engineering, Andhra University College of Engineering, 16th Sept 2021
- National Workshop on Solid Waste Management, 30-31 July, 2021
- 2nd International Conference on Sustainable Solid Waste Treatment and Management (2nd SWTM), 16-18 July 2021
- "Step-Up" Mentoring Program conducted by Osmania University Alumni Association (OUAA) and Osmania University Chemistry Foundation (OUCF), 3 July 2021
- Talk on Strategies for Sustainable Utilisation of Lignocellulosic Biomass for food, fuels, and chemicals at AICTE Sponsored Short Term Course on Advancements in Sustainable Waste Management (ASWM – 2021) organised by School of Infrastructure, IIT, Bhubaneswar, 26 June 2021
- Invited talk at The 5th Asia Pacific Biochar Conference 2021, 10-13 May 2021
- Guest lecture for Swachhta Pakhwada organised by ICMR-NIN on 15th April 2021
- ePYRO2021 during 12-13 April 2021
- Talk on Integrated approaches for the valorization of lignocellulosic biomass at BSHFEE 2021, Jodhpur organised by IIT, Jodhpur on 9th April 2021
- Webinar on Business Opportunities for Plastic Waste Utilization in Uttarakhand by AVIRAL on 16th March 2021
- India Russia Webinar on Waste to Wealth, 10-11 March 2021
- e-Workshop on "Frontiers in Sustainable Chemical Processes (FSCP-2021), Department of Chemical Engineering, NIT-Hamirpur, 1-5 February 2021
- 57th Annual Convention of Chemists, 2020 & International Conference on Recent trends in Chemical Sciences during 27-28 December 2020
- Naya Bharat e-series under Unnat Bharat Abhiyan scheme on 13th December 2020
- PyroAsia 2020 during 11-13 December 2020
- Online Workshop cum FDP programme on Technologies for Waste to Energy & Resources by NIT, Rourkela on 9th December 2020
- Online Short Term Course under TEQIP on “Modern Practices in Hydrocarbon Engineering", NIT Jalandhar, 6-10 November 2020
- Valedictory address at Kakatiya Government College, 5th November 2020
- 1st National Congress IAAS India, 1st November 2020
- Guest of honour address and lecture in Online Short Term Course on Valorization of lignocellulosic biomass towards sustainable fuels, chemicals and materials organized by Center for Energy and Environment Dr B R Ambedkar National Institute of Technology, Jalandhar, Punjab during 18th - 22nd September 2020
- TEQIP III sponsored webinar on 3 July 2020 organised by Dr B R Ambedkar National Institute of Technology, Jalandhar, Punjab, India
- ACES-2020, National Conference on Advances in Chemical Engineering and Science (ACES) scheduled to be held during 28-29 February 2020 at IISER Bhopal.
- TEQIP-III sponsored short-term course “Emerging Technologies for next generation bio-fuels bio-products” (ETNGBB-2020) on 24th Feb 2020 at NIT, Jalandhar
- 2nd edition- Global Summit on Waste Management & Waste energy (GSWM & WtE) held on 30-31 Jan 2020 in New Delhi
- International Conference on "Plant Biofactories: Strategies and Challenges" at RRAC Mumbai during 20th - 21st December 2019
- Pyro Asia 2019 First International Symposium on Analytical and Applied Pyrolysis in the Asian Region during Dec 11-13, 2019 at IIT Madras
- International Conference on New Horizons in Biotechnology 2019 at CSIR-NIIST, Trivandrum during 20th - 24th November 2019
- 10th International Symposium on Feedstock Recycling of Polymeric Materials (10th ISFR 2019) in Budapest Hungary during 26th - 29th May, 2019
- International Conference on Sustainable Solid Waste Treatment & Management (SWTM-2019) in Yangling China during 6th - 9th May, 2019
- Indo- German workshop on waste to wealth at CSIR-AMPRI, Bhopal during 23rd -27th Feb 2019
- Third International Conference on Sustainable Energy and Environmental Challenges (3rd SEEC) from 18th – 21st Dec 2018
- CSIT-ITRI seminar at New Delhi on 1st Nov 2018
- “World Biofuel Day-2018” at Vigyan Bhavan, New Delhi on 10th August 2018
- SuChem 2018 International Conference on Sustainable Chemistry for health and materials at CSIR-IICT, Hyderabad on 5th to 8th August 2018
- BRSI workshop-cum-Course on ‘Techno-economic and Life-Cycle Assessment as Tools for Sustainability Analysis during July 11-13, 2018 at CSIR-National Institute for Interdisciplinary Institute for Science and Technology (CSIR-NIIST), Trivandrum
- State level workshop on “ODF sustainability and SLRM” in Dehradun from 17th -18th April 2018
- Invited talk delivered at One day symposium on “Sustainable Chemical Process Technologies: Past, Present and Future” at Department of Chemical Engineering, Manipal University, Jaipur on 31st March 2018.
- National Conference on Bhumi Suphoshan at IICT Hyderabad, 23March 2018
- Invited talk at “Technological options for Rural India – Plastic waste management” MDWS consultative workshop organised by Ministry of Drinking water and Sanitation (MDWS), Govt. of India at New Delhi on 23 February 2018.
- Selected as a Judge for the 12th Maharashtra state Inter university research convention – Avishkar 2017 in the discipline Engineering and Technology during 15-17 January , 2018 at Mahatma Phule Krishi Vidyapeeth, Rahuri.
- Invited lecture at Conference on advances in catalysis for energy and environment (CACEE-2018) during 10-12 January , 2018 at Tata Institute of Fundamental Research (TIFR), Mumbai
- Invited lecture at International conference on Environmental Biotechnology – A promise to a clean energy and green future (EBIO-2017) during 23-25 November 2017 at Andhra University, Visakhapatnam.
- Invited lecture at International conference “Emerging trends in Biotechnology for Waste Conversion (ETBWC-2017) during October 8-10, 2017.
- Keynote speaker at National conference on waste to energy, carbon capture and storage (NCWECCS 2017) at NIT Rourkela, Rourkela during 3-5 Aug 2017.
- Plenary talk and chairing the session at International Conference on “Renewable Energy and Sustainable Environment (RESE-2017)”, July 20-22, 2017 at Dr Mahalingam College of Engineering and Technology, Pollachi, Tamilnadu, India.
- Invited talk at BIOPROCESSING INDIA 2016 on Sustainable Bioprocessing Products for Food, Nutrition, Health and Environment at Centre of Innovative & Applied Bioprocessing (CIAB), Mohali during 15-17 December 2016.
- Invited talk at 1st International Conference on Bioresource Technology for Bioenergy, Bioproducts & Environmental Sustainability during 23rd October to 26th October 2016 at Sitges, Barcelona, Spain.
- Invited talk at as a Resource Person at KIC-TEQIP Short-Term Course on "NOVEL CATALYSTS FOR INDUSTRIAL USE" in the Department of Chemical Engineering, Indian Institute of Technology, Guwahati during 24-26 Aug 2016.
- Invited talk at 17th National Work on Challenges in Catalysis Science and Technology (CCST 2016) at CSIR-Indian Institute of Chemical Technology (IICT), Hyderabad, India during 23-25 June 2016.
- Invited talk as a Resource Person at KIC-TEQIP short term course on Energy Management and Energy Efficiency at Indian Institute of Technology, Guwahati during 23-27 May 2016.
- Invited talk at UNCRD session on Role of science and technology in waste management at 3rd 3R International Scientific Conference on Material Cycles and Waste Management at Hanoi, Vietnam during 8-12 March 2016.
- Invited talk at BBS-1 2016 The First Biomass to Biovalue Summit held at Centre of Innovative Advanced Bioprocessing at Mohali, Punjab, India during 11-12 February 2016.
- Invited talk at Workshop/ Short Course on Renewable Energy and Sustainable Development at CERD, IIT BHU, Varanasi during 18-22 January 2016.
- Invited talk at "15th Solid Waste Management Experts in Asia and Pacific Islands" at Mielparque Hotel, Tokyo, Japan sponsored by Ministry of Environment, Japan during 21-25 December 2015.
- Invited talk at PACIFICHEM 2015-The 2015 International Chemical Congress of Pacific Basin Societies, Honolulu, Hawaii, USA during 15-20 December 2015
- Invited talk at "Short Time Course on Current Opportunities and New Directions in Chemical Sciences and Technology" at Dr B R Ambedkar National Institute of Technology, Jalandhar, Punjab, India on 7th December 2015.
- Invited talk at "Practical hands for process of Biofuel production and catalysis, characterization and engine applications" at Sardar Swaran Singh National Institute of Bio-energy, Kapurthala, Punjab on 4th December 2015.
- Invited talk at International Conference on Advances in Bioprocess Technology (Biospectrum 2015) in Tiruvalla, India during during 26-28 November 2015.
- Invited talk at International Conference on New Horizons in Biotechnology (NHBT 2015) in Trivandrum, India during 22-25 November 2015.
- Invited talk at One day workshop on "Advances in Algal Biotechnology" in IIT Bombay, Mumbai, India during 21 November 2015.
- Invited talk at 8th International Symposium on Feedstock Recycling of Polymeric Materials (8th ISFR) at Leoben, Austria during 9-11 September 2015.
- Keynote speaker at International Workshop on Energy and Resources Development (IWERD-2015) at IIT-BHU, Varanasi, India during 16-17 May 2015.
- Invited talk at first International Conference on 'Recent Advances in Bio-energy Research' (ICRABR-2015) at Sardar Swaran Singh National Institute of Renewable Energy, Kapurthala, India during 25-28 February 2015.
- Invited talk at Emerging Trends and Challenges in Chemical Research (ETCCR-2015) at Mahatma Gandhi University, Nalgonda, India at 14 February 2015.
- Invited talk at 2nd International Conference on Bioenergy, Environment & Sustainable Technologies (BEST 2015) at Arunai Engineering College, Tiruvannamalai, India during 28-31 January 2015.
- Invited talk at Sardar Swaran Singh National Institute of Renewable Energy (SSS-NIRE), Kapurthala, India on 19 January 2015.
- Invited talk at 5th Asia-Oceania Conference on Green and Sustainable Chemistry (AOC-5 GSC) at India Habitat Centre, New Delhi, India during 15-17 January 2015.
- Invited talk at Continuing Education Program on Emerging trends in Biofuel at Defence Institute of Bioenergy Research (DIBER), DRDO, Haldwani Uttarakhand during 10-14 November 2014.
- Invited talk at International Conference on Emerging Trends in Biotechnology (ICETB-2014) at Jawaharlal Nehru University, New Delhi during 6-9 November 2014.
- Guest of Honor address at Kakatiya Government College, Warangal, India during 1-5 November 2014
- Invited talk at Indo-Swedish workshop on bio-based economy in Stockholm, Sweden during 20-21 August 2014
- Invited talk at 16th National Workshop on Catalysis for Sustainable Development at CSIR-NEERI, Nagpur during 4-5 February 2014
- Invited talk at Technical Seminar on Plastics Recycling & Waste Management Technical Seminar on “Plastics Recycling & Waste Management” organised by Dept. of Chemicals & Petrochemicals, Ministry of Chemicals & Fertilizers, Govt. of India at Ajmer, Rajasthan on 20 January 2014
- Invited as key speaker at Indo-Finnish Workshop in Green Chemistry in the Theme of Green catalytic approaches for production of biofuels and chemical during 13-14 December 2013
- Invited talk on Thermochemical platform for sustainable production of lignocellulosic biofuels at International Conference on Advances in Biotechnology and Bioinformatics (ICABB 2013), Dr. D. Y. Patil Vidyapeeth (Deemed University), Pune, India during 25-27 November 2013
- Invited talk at 3rd National Conference on Recent Advances in Bio-Energy Research at SSS-NIRE, Kapurthala during 22-24 November 2013
- Invited talk on Catalysis for 2nd and 3rd Generation Biofuels at 5th India-Korea Joint Workshop on Bioenergy at CSIR-NIIST, Trivandrum during 9-10 September 2013
- Invited talk on Plastics Waste Management and Recycling Industry at the Conference on Potential of Plastic Processing Industry in Northern India at Hotel Mount View, Chandigarh on 25 June, 2013
- Invited talk at the workshop on The Development of Sustainable Catalytic Reaction System using carbon dioxide and Water at Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore (December 2012)
- Invited talk at National Conference on Recent Advances in Bio-Energy Research at SSS-NIRE, Kapurthala during 7-8 December 2012
- Invited talk on Energy efficient thermo-chemical processes for biorefinery: Role of catalysis at 2nd International Indo-German Symposium on Green chemistry and catalysis for sustainable development at University Institute of Chemical Technology, Mumbai during 29-31 October 2012
- Invited talk on Effective and Environment Friendly Conversion Methods for Waste Plastics at Plastic Waste Management – Recycling Technologies organized by Ministry of Chemicals and Fertilizers, Govt. of India (March 2012)
- Invited talk on Environment friendly conversion methods of waste plastics at Workshop on Plastics Waste Management – Recycling Technologies at Hotel THE CLARIDGES, New Delhi, India on 21 March 2012
- Invited talk at CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum during International Conference on New Horizons on Biotechnology (November 2011)
- Invited talk at CSIR-Central Institute of Medicinal Aromatic Plants, Lucknow, India during 80th Society of Biological Chemists, India (November 2011)
- Invited lecture on Opportunities for thermochemical valorization of lignocellulosic biomass and discussed the possible collaborations in the field of biomass conversions at VTT, Finland on 10 October 2011
- Plenary talk on Catalysts for the conversion of waste plastics: challenges for the development of industrial processes at 6th International Symposium on Feedstock Recycling of Polymeric Materials held at Toledo, Spain and chaired the technical session during the conference during 4-6 October 2011
- Invited talk on Green Chemistry and Catalysis for Lignocellulosic Biofuels at National Seminar on Green Chemistry and Catalysis held at University Institute of Chemical Technology, Mumbai during 3-4 March, 2011
- Invited talk on Sustainable Biofuels and Chemicals from Lignocellulosic Biomass at PACIFICHEM 2010, held during 15-20 December 2010 in Hawaii, USA
- Invited lecture on Biofuels for sustainable development of Under developed regions delivered at National Conference on Rene/wable Energy for Development of Under developed areas with particular reference to North-East India at Tezpur University, Tezpur, Assam, 23-25 March, 2010
- Invited lecture at Sichuan University, 2009
- Invited lecture at Korea Institute of Energy Research (KIER), April 2006
- Invited lecture and Chairing the session in PACIFICHEM, December 2005
- Invited Lecture at University of Leeds, November 2005
- Invited talk in Seminar organized by Industrial Technology Research Institute (ITRI/CESH), November 2004