Gold, with its high electrical conductivity and resistance to corrosion, is a critical metal used in solar panels, fuel cells, mobile phones, computers, circuit boards, medical devices, and more. Copper, too, is a critical metal used in electrical wiring, power cables, wind turbine and solar panel components, as well as for defense, consumer electronics, and other industry applications.
Given the high value of these metals, there is significant incentive to recover these valuable metals from waste streams domestically. However, current methods for extracting these metals from waste streams are toxic (employing acid or cyanide-based leaches for gold extraction, for example) and expensive, requiring significant amounts of energy for high temperature smelting processing.
Solution
In 2013, Daniel Sun, a research assistant at Lawrence Berkeley National Laboratory’s (Berkeley Lab’s) Molecular Foundry, worked on developing new material technologies at the Molecular Foundry. These technologies were based on “metal-organic frameworks” which combined metal ions with organic linkers in highly porous, super-high-surface-area nanostructures. He was struck by how well the technology worked to separate heavy metals from a variety of different waste and wastewater streams, without the use of toxic chemicals. In 2020, after completing his Ph.D., Daniel recognized the technology’s commercial potential and obtained a licensing option from Berkeley Lab. He then founded Sunchem to bring the technology to market.
Daniel moonlighted at Sunchem from 2020 to 2022, while working part-time for a battery start up. He obtained lab space, continued to develop the technology and received multiple non-dilutive grants to help fund the company.
In 2022, he was accepted into Cyclotron Road, a Department of Energy Lab-Embedded Entrepreneurship Program (LEEP) node, for a two-year fellowship, gaining access to more Berkeley Lab resources and entrepreneurship training offered by Cyclotron Road partner Activate. He teamed up with Dr. Dana Hernandez, who is now the co-founder & CTO of Sunchem and the team grew to six full-time employees.
Said Daniel, “We had demonstrated the higher performance of our materials in batch conditions. Cyclotron Road gave us the resources to assess the performance in a dynamic continuous operation similar to the conditions in industry, allowing us to deploy the new technology into a fully-integrated metal recovery process. This de-risked the technology sufficiently to make it investable and attractive to industry.”
Today, the company’s precision separation technologies have been demonstrated in multiple industrial situations across the critical metal value chain. For instance, Sunchem has produced 99.999% pure gold from a U.S. device manufacturer’s waste scrap, which meets the metrics for the gold to be reintegrated back into device manufacturing. They’ve purified 99% pure gold and 99% pure copper from waste printed circuit boards (PCBs) provided by a local Bay Area recycler and now have metric ton scale commitment for pilots. In the mining sector, their Nano Leach formulation can liberate copper into water, while leaving behind contaminants such as toxic arsenic, in the solid form. This not only significantly helps reduce energy consumption for a given mining operation, but opens up new copper assets that could not be traditionally mined before.
Said Daniel, “Down the road, the technology can be tuned to capture other elements, such as gallium or rare earth metals. We currently have a project with a large solar cell recycling company in the U.S. focusing on separating silver with some really exciting results.”
Impact
With these continued technological advances, the company is now attracting the attention of industry. In the fall of 2024, mining giant Rio Tinto, announced it would provide support to Sunchem and five other startups through the Founders Factory Mining Accelerator. The accelerator has helped Sunchem identify use cases for its technology and unlock potential future commercial opportunities with Rio Tinto.
As a Forbes article noted, “These startups will receive seed capital, access to Rio Tinto for commercial opportunities and a four-month program of masterclasses and operational support. Rio Tinto provides advanced R&D facilities that help startups accelerate their development by sharing insights from previous projects. Rio can also act as a first customer, enabling startups to scale their solutions rapidly if proven viable.”
Said Daniel, “The Founders Factory program allows us to work with Rio Tinto’s feedstocks, understand their industrial situations, and help them increase the production of their critical metals while increasing energy-efficiency within their operations.”
Sunchem also continues to be recognized for its potential. In April, 2025, the National Renewable Energy Laboratory’s Industry Growth Forum named Sunchem “Best Overall Venture.”
Having raised $1,260,000 to date, with the majority from non-dilutive funding agencies, which include the National Science Foundation, Department of Energy, and California Energy Commission, the company is now fundraising $2.5M for their seed round to build and operate their pilot facility. To date, Sunchem has filled over half the round, including a $500,000 prototype award from the state of California.